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We review the recent development of Conservation Agriculture (CA) for rice-based smallholder farms in the Eastern Gangetic Plain (EGP) and the underpinning research on agronomy, weed control, soil properties and greenhouse gas emissions being tested to accelerate its adoption in Bangladesh. The studies are based mostly on minimum soil disturbance planting in strip planting (SP) mode, using the Versatile Multi-crop Planter (VMP), powered by a two-wheel tractor (2WT). One-pass SP with the VMP decreased fuel costs for crop establishment by up to 85% and labour requirements by up to 50%. We developed strip-based non-puddled rice (Oryza sativa) transplanting (NPT) in minimally-disturbed soil and found that rice grain yield increased (by up to 12%) in longer-term practice of CA. On farms, 75% of NPT crops increased gross margin. For non-rice crops, relative yield increases ranged from 28% for lentil (Lens culinaris) to 6% for wheat (Triticum aestivum) on farms that adopted CA planting. Equivalent profit increases were from 47% for lentil to 560% for mustard (Brassica juncea). Moreover, VMP and CA adopting farms saved 34% of labour costs and lowered total cost by up to 10% for production of lentil, mustard, maize (Zea mays) and wheat. Effective weed control was obtained from the use of a range of pre-emergent and post-emergence herbicides and retention of increased crop residue. In summary, a substantial body of research has demonstrated the benefits of CA and mechanized planting for cost savings, yield increases in many cases, increased profit in most cases and substantial labour saving. Improvement in soil quality has been demonstrated in long-term experiments together with reduced greenhouse gas emissions.
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agriculture
Review
Conservation Agriculture for Rice-Based Intensive
Cropping by Smallholders in the Eastern
Gangetic Plain
Richard W. Bell 1,* , Md. Enamul Haque 1, M. Jahiruddin 2, Md. Moshiur Rahman 3,
Mahfuza Begum 3, M. A. Monayem Miah 4, Md. Ariful Islam 5, Md. Anwar Hossen 6,
Nazmus Salahin 7, Taslima Zahan 8, Mohammad Mobarak Hossain 9, Md. Khairul Alam 10 and
Mir Nurul Hasan Mahmud 11
1School of Veterinary and Life Sciences, Murdoch University, South St, Murdoch WA 6150, Australia;
e.haque@murdoch.edu.au
2Department of Soil Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh;
m_jahiruddin@yahoo.com
3Department of Agronomy, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh;
rahmanag63@gmail.com (M.M.R.); mzap_27@yahoo.co.uk (M.B.)
4Agricultural Economics Division, Bangladesh Agricultural Research Institute, Gazipur 1701, Bangladesh;
monayem09@yahoo.com
5Pulses Research Centre, Bangladesh Agricultural Research Institute, Ishurdi, Pabna 6620, Bangladesh;
arifbau06@gmail.com
6FMPHT Division, Bangladesh Rice Research Institute, Gazipur 1701, Bangladesh; ahossenbrri@gmail.com
7Soil Science Division, Bangladesh Agricultural Research Institute, Gazipur 1701, Bangladesh;
nsalahin@yahoo.com
8On-farm Research Division, Bangladesh Agricultural Research Institute, Gazipur 1701, Bangladesh;
taslimazahan_tzp@yahoo.com
9
Rice Breeding Platform (Breeding for Favorable Environment), International Rice Research Institute, Metro
Manila 1301, The Philippines; shakilmoba@gmail.com
10 Soil Science Division, Bangladesh Agricultural Research Institute, Gazipur 1701, Bangladesh;
khairul.krishi@gmail.com
11 Irrigation and Water Division, Bangladesh Rice Research Institute, Gazipur 1701, Bangladesh;
hasan11bau@yahoo.com
*Correspondence: r.bell@murdoch.edu.au; Tel.: +614-0513-1429
Received: 31 October 2018; Accepted: 19 December 2018; Published: 22 December 2018


Abstract:
We review the recent development of Conservation Agriculture (CA) for rice-based
smallholder farms in the Eastern Gangetic Plain (EGP) and the underpinning research on agronomy,
weed control, soil properties and greenhouse gas emissions being tested to accelerate its adoption in
Bangladesh. The studies are based mostly on minimum soil disturbance planting in strip planting (SP)
mode, using the Versatile Multi-crop Planter (VMP), powered by a two-wheel tractor (2WT). One-pass
SP with the VMP decreased fuel costs for crop establishment by up to 85% and labour requirements
by up to 50%. We developed strip-based non-puddled rice (Oryza sativa) transplanting (NPT) in
minimally-disturbed soil and found that rice grain yield increased (by up to 12%) in longer-term
practice of CA. On farms, 75% of NPT crops increased gross margin. For non-rice crops, relative
yield increases ranged from 28% for lentil (Lens culinaris) to 6% for wheat (Triticum aestivum) on
farms that adopted CA planting. Equivalent profit increases were from 47% for lentil to 560% for
mustard (Brassica juncea). Moreover, VMP and CA adopting farms saved 34% of labour costs and
lowered total cost by up to 10% for production of lentil, mustard, maize (Zea mays) and wheat.
Effective weed control was obtained from the use of a range of pre-emergent and post-emergence
herbicides and retention of increased crop residue. In summary, a substantial body of research has
demonstrated the benefits of CA and mechanized planting for cost savings, yield increases in many
Agriculture 2019,9, 5; doi:10.3390/agriculture9010005 www.mdpi.com/journal/agriculture
Agriculture 2019,9, 5 2 of 17
cases, increased profit in most cases and substantial labour saving. Improvement in soil quality has
been demonstrated in long-term experiments together with reduced greenhouse gas emissions.
Keywords:
crop establishment; crop residue retention; fuel use; minimal soil disturbance; planter;
non-puddled rice transplanting; strip planting
1. Introduction
Agriculture in Bangladesh is facing the ongoing challenge of increasing food security for its
growing population (currently 164 million people [
1
] and expected to reach 205 million by 2050 [
2
]) and
improving overall land use sustainability, while decreasing costs of crop production to increase farm
profitability. In a recent review paper on the practice of Conservation Agriculture (CA) (i.e., minimum
mechanical soil disturbance, organic soil cover and crop species diversification) by smallholders [
3
], the
authors concluded that it was an approach that could improve soil health, decrease costs of production
and increase crop profitability. The present paper outlines the development of a form of CA suited
to rice-based cropping in small farms of the Eastern Gangetic Plain (EGP) with particular reference
to Bangladesh.
The nation-wide spread of mechanized tillage with two-wheel tractors (2WT), and development
over the past decade of a range of minimum soil disturbance planters for 2WT, provide a platform
for implementing CA principles that will decrease costs of crop production (less fuel consumption
and decreased labour requirements) and improve the fertility of soils in Bangladesh. Evaluation of
the Versatile Multi-crop Planter (VMP) [
4
6
] showed promising results for the establishment and
yield of a range of crops in rainfed cropping systems. This novel, lightweight, low-cost planter is
now being manufactured in Bangladesh. This paper reviews the systematic work completed on the
implications of CA adoption in rice-based systems and on acceleration of adoption of planters for
crop establishment on farms. The development of CA in Bangladesh, incorporating the new planters,
through on-going research and development demonstrated that crop yields were at least maintained
using CA approaches. Effective strategies were developed and evaluated for the engagement of service
providers, extension, machinery manufacturers and farmers in the implementation of a form of CA
suited to the cropping areas of Bangladesh.
2. Research Approach and Study Areas
The research discussed here, conducted during 2008–2018, was focused on target areas to provide
a range of soils and cropping systems for the evaluation of CA in Rajshahi, Mymensingh, Rajbari and
Thakurgoan districts in Bangladesh (Figure 1). The research reviewed was mostly conducted by a
Conservation Agriculture project supported by the Australian Centre for International Agricultural
Research (2012–2017). In each of the study areas, cropping systems experiments were established
to evaluate the most suitable minimum soil disturbance options and the key limitations to CA
and its profitability when applied to rice-based cropping. Experiments were conducted mostly on
farms involving farmers’ groups and machinery contractors (called local service providers (LSP)),
where monsoon (Kharif-2 season) rainfed rice (aman rice), cool-dry season high yield irrigated rice
(boro rice) and other non-rice crops in the dry (Rabi) season, e.g., oilseed, pulse or wheat (Triticum
aestivum), and pre-monsoon season (Kharif 1) crops, such as aus rice, mung bean (Vigna radiata) or jute
(Corchorus capsularis L.), were established, depending on their local suitability. These experiments were
supplemented by research and development focused on improvements in minimum soil disturbance
machinery, starting with the VMP design, field experiments designed for the diagnosis of agronomic
constraints in CA related to weeds and nutrition and studies on improvements in soil fertility associated
with minimum soil disturbance, increased retention of crop residues and more diverse crop rotations
including pulses and oilseeds.
Agriculture 2019,9, 5 3 of 17
Agriculture 2018, 8, x FOR PEER REVIEW 3 of 17
Figure 1. Map of Bangladesh showing the study districts (Thakurgaon, Rajshahi, Mymensingh and
Rajbari) marked with different colours.
SCALE
Figure 1.
Map of Bangladesh showing the study districts (Thakurgaon, Rajshahi, Mymensingh and
Rajbari) marked with different colours.
Agriculture 2019,9, 5 4 of 17
To accelerate the development and adoption of CA in Bangladesh, a network of farmers, LSPs,
extension officers, Non-government Organizations (NGOs), banks and machinery manufacturers
was established. The purpose of this network was to identify constraints to adoption of CA in the
machinery and related services value chains, and advocate for research and development on relevant
minimum tillage machinery, crop agronomy packages (especially weed control) and soil management
technologies for specific cropping systems. This farmer network, known as the Conservation
Agriculture Service Providers Association (CASPA), serves as a stakeholder group for dissemination
of findings to farmers.
2.1. Climate of The Studied Areas in EGP
The average annual rainfall in Mymensingh district is more than 2500 mm, which wis higher
than Thakurgaon district (2218 mm), followed by Rajbari district (2005 mm) and the lowest is in
Rajshahi district (1581 mm). In all locations where the present studies were done, about 80% of total
rainfall occurs during June to September. The average maximum temperatures are 36, 36, 33 and
32
C in Rajshahi, Thakurgaon, Rajbari and Mymensingh, respectively, in April. The lowest average
temperatures are 11–12 C in January (Figure 2).
Agriculture 2018, 8, x FOR PEER REVIEW 4 of 17
To accelerate the development and adoption of CA in Bangladesh, a network of farmers, LSPs,
extension officers, Non-government Organizations (NGOs), banks and machinery manufacturers
was established. The purpose of this network was to identify constraints to adoption of CA in the
machinery and related services value chains, and advocate for research and development on relevant
minimum tillage machinery, crop agronomy packages (especially weed control) and soil
management technologies for specific cropping systems. This farmer network, known as the
Conservation Agriculture Service Providers Association (CASPA), serves as a stakeholder group for
dissemination of findings to farmers.
2.1. Climate of The Studied Areas in EGP
The average annual rainfall in Mymensingh district is more than 2500 mm, which wis higher
than Thakurgaon district (2218 mm), followed by Rajbari district (2005 mm) and the lowest is in
Rajshahi district (1581 mm). In all locations where the present studies were done, about 80% of total
rainfall occurs during June to September. The average maximum temperatures are 36, 36, 33 and 32
°C in Rajshahi, Thakurgaon, Rajbari and Mymensingh, respectively, in April. The lowest average
temperatures are 11–12 °C in January (Figure 2).
Figure 2. Monthly average rainfall (mm), average maximum and minimum temperature (°C) in study
locations (called Upazillas). Data (1980–2012) were collected from nearest weather stations of the
Metrological Department of Bangladesh and from [7]. Lines with filled triangles and squares
represent the average minimum and maximum monthly temperatures, respectively, and bars
represent the monthly average total rainfall.
2.2. Cropping Pattern
The study areas in Bangladesh are characterized by diverse crop rotations. Major cropping
patterns of the study locations in Thakurgaon are aman rice–potato (Solanum tuberosum)–maize, aman
rice–potato–boro rice, aman rice–wheat–fallow and aman rice–boro rice. The cropping patterns in the
study area of Rajshahi are aman rice–lentil–aus rice, aman rice–mustard–boro rice, aman rice–wheat–
mung bean and aman rice–wheat–fallow. In the study location of Mymensingh, the cropping patterns
are aman rice–wheat–mung bean and aman rice–fallow–boro rice. In Rajbari, major cropping patterns
Figure 2.
Monthly average rainfall (mm), average maximum and minimum temperature (
C) in study
locations (called Upazillas). Data (1980–2012) were collected from nearest weather stations of the
Metrological Department of Bangladesh and from [
7
]. Lines with filled triangles and squares represent
the average minimum and maximum monthly temperatures, respectively, and bars represent the
monthly average total rainfall.
2.2. Cropping Pattern
The study areas in Bangladesh are characterized by diverse crop rotations. Major cropping
patterns of the study locations in Thakurgaon are aman rice–potato (Solanum tuberosum)–maize, aman
rice–potato–boro rice, aman rice–wheat–fallow and aman rice–boro rice. The cropping patterns
in the study area of Rajshahi are aman rice–lentil–aus rice, aman rice–mustard–boro rice, aman
rice–wheat–mung bean and aman rice–wheat–fallow. In the study location of Mymensingh, the
Agriculture 2019,9, 5 5 of 17
cropping patterns are aman rice–wheat–mung bean and aman rice–fallow–boro rice. In Rajbari, major
cropping patterns are aman rice–onion (Allium cepa)–jute, aman rice–wheat–jute and aman rice–garlic
(Allium sativum)–jute. Planting and harvesting dates of the crops in the study areas are given in
Figure 3.
Figure 3.
Major crops in the studied areas showing planting dates and harvest dates for the major
crops referred to in the present study.
2.3. Rice Cultivation in Conservation Agriculture
Soil puddling for transplanting rice seedlings is not a CA practice. For the adoption of CA in
rice-based cropping systems, a method of rice establishment involving minimum soil disturbance
is needed. We developed non-puddled transplanting (NPT) for establishment of rice seedlings in
minimally-disturbed soil [
8
]. The NPT method involves strip tillage in dry soil using the VMP, followed
by saturation of the soil for 18–24 h to soften the soil in the strip. Seedlings are then transplanted into
the non-puddled strip. Non-puddled transplanting can be applied into standing crop residues, and
usually involves application of a non-selective herbicide such as glyphosate to control weeds before
strip preparation. Grain yield increased by up to 12% with the longer-term practice of NPT rice together
with SP of other crops in the rotation, while no yield loss was reported relative to the conventional
puddled transplanting (CP) of rice. However, land preparation cost was reduced significantly by NPT
rice establishment.
In the on-farm comparisons of NPT in minimally-disturbed soil, few farmers obtained lower
yields than in the rotary-tilled CP fields. In the monsoon season, 53 out of 66 farmers who practiced
NPT reported higher net returns than in full tilled CP while 49 out of 66 farmers reported higher rice
grain yield (Figure 4). In boro season of 2013, 2014 and 2015, the net return was higher in 78 of 84 cases
in NPT rice while 62 of 84 had the same or higher grain yield than CP (Figure 4).
Agriculture 2019,9, 5 6 of 17
Agriculture 2018, 8, x FOR PEER REVIEW 6 of 17
Figure 4. Individual farmer’s wet season (aman) (A) and irrigated rice (called boro) (C) grain yield (t
ha1), and net return of aman (B) and boro rice (D) comparison between paired crops established by
non-puddled transplanting of rice seedlings (NPT) (blue line with round bullets) relative to
conventionally-puddled transplanting of rice seedling (CP) (orange coloured bars) during 2013, 2014
and 2015. The values for paired crops are arranged in order of the NPT net return for each year. Net
return values are based on the average market price for rice in the three years. Rice crops were
generally sown on different fields in each year.
Figure 4.
Individual farmer’s wet season (aman) (
A
) and irrigated rice (called boro) (
C
) grain yield
(t ha
1
), and net return of aman (
B
) and boro rice (
D
) comparison between paired crops established
by non-puddled transplanting of rice seedlings (NPT) (blue line with round bullets) relative to
conventionally-puddled transplanting of rice seedling (CP) (orange coloured bars) during 2013, 2014
and 2015. The values for paired crops are arranged in order of the NPT net return for each year. Net
return values are based on the average market price for rice in the three years. Rice crops were generally
sown on different fields in each year.
Agriculture 2019,9, 5 7 of 17
2.4. Designing Minimum Tillage Planters for Improved Operation and Effectiveness
There are few planters available for CA planting of crops in the EGP using the 2WT, and none were
considered to have sufficient flexibility or versatility to develop a profitable LSP business operation for
crop establishment in the diversified cropping systems of the EGP [
9
]. The VMP was designed and
developed as a seeder for smallholder farms and operation by a 12–16 horsepower 2WT making it
suitable for the EGP [
4
]. It can deliver seed and fertilizer into the soil behind the tyres and the rates of
application can be adjusted. Seeding depth and row spacing can also be adjusted while planting by
strip planting (e.g., SP), zero tillage, single pass shallow tillage, shallow beds and conventional tillage
(CT). The shaft and brackets of the VMP were designed (Figure 5) for flexibility for multi-crop planting
with basal fertilizer banding in line, and capacity for rapid adjustment of seed and fertilizer rate, seed
depth and row spacing on crop-by-crop and field-by-field bases.
Agriculture 2018, 8, x FOR PEER REVIEW 7 of 17
2.4. Designing Minimum Tillage Planters for Improved Operation and Effectiveness
There are few planters available for CA planting of crops in the EGP using the 2WT, and none
were considered to have sufficient flexibility or versatility to develop a profitable LSP business
operation for crop establishment in the diversified cropping systems of the EGP [9]. The VMP was
designed and developed as a seeder for smallholder farms and operation by a 12–16 horsepower 2WT
making it suitable for the EGP [4]. It can deliver seed and fertilizer into the soil behind the tyres and
the rates of application can be adjusted. Seeding depth and row spacing can also be adjusted while
planting by strip planting (e.g., SP), zero tillage, single pass shallow tillage, shallow beds and
conventional tillage (CT). The shaft and brackets of the VMP were designed (Figure 5) for flexibility
for multi-crop planting with basal fertilizer banding in line, and capacity for rapid adjustment of seed
and fertilizer rate, seed depth and row spacing on crop-by-crop and field-by-field bases.
Figure 5. VMP, attached to a 2WT: in transportation mode (left); and field operation mode (right).
A related planter that only has strip planting capability is the Versatile Strip Seed Drill (VSSD)
[9], also developed in Bangladesh. The VMP [4] and VSSD [9] have now been tested extensively in
Bangladesh. Both have the capacity for use as a 2WT-based CA planter in cropping systems used by
smallholder farmers more widely in Asia, Africa and other regions.
The field capacity of VMP was 0.07 ha h
1
for SP which was 34% higher than for CT due to the
reduced number of operations [4,5]. Land preparation cost by VMP was decreased by up to 75% for
SP compared to CT. The VMP was capable of sowing many crops from small jute seed (2 g
1000
seeds)
up to maize (160 g
1000
seed) (Table 1). The latest VMP (Model 13, Figure 5) weighs 152 kg excluding
the driver’s seat and rear wheel for road transportation and ex-factory price is US$1000.
Table 1. Seed rate, row spacing and seeding methods for strip planting of crops using the VMP.
Name of The Crops Seed Rate (kg ha
1
) Adjustable Row
Spacing (cm)
Distance between Seeds
(cm)
Direct seeded rice 16–18 20 20
Wheat 110–120 20 Continuous
Maize (hybrid) 83,330 plant ha
1
58–60 20
Mung bean 28–30 30 3–4
Lentil 30–34 20 Continuous
Sesame (Sesamum Indicum L.) 4–5 20 Continuous
Mustard 3.5–4.5 20 Continuous
Chickpea (Cicer arietinum L.) 40–45 30 3–4
Jute 3–4 20 Continuous
Fuel consumption while strip planting by VMP decreased from 33.1 to 5.83 L ha
1
) (Table 2). The
maximum cost (US$41.47 ha
1
) of land preparation and seeding was incurred in the case of CT system
and the lowest (US$10.27 ha
1
) for strip planting.
Figure 5. VMP, attached to a 2WT: in transportation mode (left); and field operation mode (right).
A related planter that only has strip planting capability is the Versatile Strip Seed Drill (VSSD) [
9
],
also developed in Bangladesh. The VMP [
4
] and VSSD [
9
] have now been tested extensively in
Bangladesh. Both have the capacity for use as a 2WT-based CA planter in cropping systems used by
smallholder farmers more widely in Asia, Africa and other regions.
The field capacity of VMP was 0.07 ha h
1
for SP which was 34% higher than for CT due to the
reduced number of operations [
4
,
5
]. Land preparation cost by VMP was decreased by up to 75% for
SP compared to CT. The VMP was capable of sowing many crops from small jute seed (2 g
1000
seeds)
up to maize (160 g
1000
seed) (Table 1). The latest VMP (Model 13, Figure 5) weighs 152 kg excluding
the driver’s seat and rear wheel for road transportation and ex-factory price is US$1000.
Table 1. Seed rate, row spacing and seeding methods for strip planting of crops using the VMP.
Name of The Crops Seed Rate (kg ha1)Adjustable Row Spacing
(cm)
Distance between Seeds
(cm)
Direct seeded rice 16–18 20 20
Wheat 110–120 20 Continuous
Maize (hybrid) 83,330 plant ha158–60 20
Mung bean 28–30 30 3–4
Lentil 30–34 20 Continuous
Sesame (Sesamum Indicum L.) 4–5 20 Continuous
Mustard 3.5–4.5 20 Continuous
Chickpea (Cicer arietinum L.) 40–45 30 3–4
Jute 3–4 20 Continuous
Fuel consumption while strip planting by VMP decreased from 33.1 to 5.83 L ha
1
) (Table 2). The
maximum cost (US$41.47 ha
1
) of land preparation and seeding was incurred in the case of CT system
and the lowest (US$10.27 ha1) for strip planting.
Agriculture 2019,9, 5 8 of 17
Table 2.
Effect of crop establishment mode by the VMP on fuel consumption, field capacity, labour
requirement and cost of land preparation and seeding for lentil, chickpea, mung bean and black gram
(Vigna mungo) in clay soil on the High Barind Tract, Rajshahi, Bangladesh, 2010–11. Summarized
from [5].
Tillage Type Field Capacity
(ha hr1)
Fuel Consumption
(l ha1)
Labour
Requirement,
(person-hr ha1)
Cost of Land
Preparation,
Fertilizing and
Seeding a(US$ ha1)
Conventional (4 tillage passes) (CT) 0.03 c 33.1 a 48.1 a 41.5 a
Shallow depth full tillage (single pass)
0.07 a 20.6 c (38) 15.4 c (68) 19.8 d (52)
Strip planting (single pass) 0.07 a 5.83 e (82) 15.3 c (68) 10.3 d (75)
Zero tillage (single pass) 0.06 ab 16.6 d (50) 17.3 c (64) 18.1 c (23)
Values in parentheses indicate the percent saving over CT. Values in a column, followed by a common letter are not
significantly different at p< 0.01 by Duncan’s Multiple Range Test.
a
Considering variable costs for labour (land
preparation @Taka 30 and seeding @Taka 20 ha1) and diesel fuel (@Taka 45 L1); 1 US$ = 68 Taka in 2010–11).
2.5. Weed Management—Including the Role of Residue
Herbicidal weed control is now a common practice for conventional full tillage-based
agriculture [
10
]. Experiments were conducted to assess the effectiveness of herbicide and/or crop
residue use to control weeds under CA in a range of crops. The benefit–cost ratio (BCR) with SP and
NPT followed by the application of pre-emergence and post emergence herbicides was much greater
than for CT and CP and hand weeding [
11
,
12
]. Retention of 50% residue increased the grain yield by
4% and BCR by 9%. The weed seed bank study revealed that, after the two-year field experiment, the
practice of CP for rice and CT for non-rice crops enriched the seedbank weed numbers by 13% while
SP and NPT reduced seedbank numbers by 17%. Residue retention diminished the weed seedbank
numbers by 11%. Even though residue retention levels did not exceed 50%, the increased residue
helped to suppress weeds and is a useful component of the weed control strategy of CA practice [
13
].
After 3–5 years of continuous CA practice, the weed seedbank was reduced by 30–35% compared to
the current conventional practice [
13
]. Hence, in the medium to long term, there is likely to be less
difficulty suppressing weeds in the CA fields.
From a number of experiments with both rice and wheat as well as mustard, the best weed control
was obtained from sequentially applied pre-emergence and post-emergence herbicides. Herbicides
applied in NPT aman rice had no residual effects on the succeeding crops of wheat, lentil or sunflower
(Helianthus annuus) [
11
]. Similarly, no toxicity was detected in mung bean grown after various
herbicides were used to treat weeds in wheat [
14
]. Phytotoxic effects of some herbicides were recorded
in rice and wheat, depending on cultivar and rate of herbicide application. While almost all rice and
wheat cultivars tested were tolerant to herbicides at the label rate, there were some exceptions. The
implications of these findings are that screening of cultivars, especially new cultivar releases, needs to
be institutionalized within national breeding programmes, since the use of herbicides for weed control
(for conventional and CA practice) is quickly becoming the norm rather than an exception in farmers’
fields in the EGP [10].
Field experiment showed that application of herbicides has significantly reduced weed infestation
in wheat and rice fields under SP and provided up to 227% and 28% higher grain yield of SP-based
wheat and NPT-based rice, respectively, compared to non-weeded plot [11,12].
For aman rice established by NPT, the best weed control was obtained from sequentially applied
pyrazosulfuron-ethyl, orthosulfamuron and butachlor + propanil [
14
]. It provided similar or better
grain and straw yield as weed-free control and gave the highest net benefit among all treatments during
successive years. Selection of herbicides with different modes of action is an essential tool to minimize
the risk of herbicide resistance developing in weeds. From several papers [
11
16
], it can be concluded
that rotational use at the recommended dose of the effective herbicides in a rice–wheat–mung bean
pattern could be effective to control weeds in the CA system as the herbicides applied to rice and
wheat had no residual effect on the succeeding crops. Moreover, almost all rice and wheat varieties
were tolerant to herbicides at the recommended rate on the product label.
Agriculture 2019,9, 5 9 of 17
2.6. Benefit of CA for Soil Fertility
After 2.5 years in both legume- and cereal-dominated rotations, the soil organic carbon (SOC)
concentration and SOC content at 0 to 7.5 cm soil depth were greater in SP + NPT than CT + CP [
17
].
By contrast, the SOC concentration and content at 7.5 to 15 cm remained unchanged between CT + CP
and SP + NPT. Soil organic C losses through the emission of CO
2
were greater in CT + CP than SP +
NPT. High residue retention increased SOC concentration, SOC content, and CO
2
emission from soil.
In the cereal-dominated rotation, SP + NPT sequestered 0.20–0.44 Mg C ha
1
annually, while CT + CP
caused 0.41–0.66 Mg C ha
1
loss at 0–15 cm soil depth. In contrast to the legume-dominated rotation,
neither CT + CP nor SP + NPT sequestered SOC but SP + NPT reduced the loss by
0.40 Mg C ha1
annually compared to CT + CP. Based on the C balance, it is estimated that annual organic matter inputs
of
4 Mg C ha1
under SP + NPT and 6 Mg C ha
1
under CT + CP condition in the legume-dominated
system, and 1 Mg C ha
1
under SP + NPT and 8 Mg C ha
1
under CT + CP condition in the
cereal-dominated system, would be required to maintain SOC at the antecedent level. Application
of SP + NPT and retention of higher levels of crop residue (HR) have the potential for increasing C
sequestration and N accumulation, while reducing N losses. Such improvements in soil properties and
thereby in crop growth and yields, were obtained after 2–3 years of CA practice in rice-based systems
of Bangladesh.
After five years practicing CA (using crop establishment by SP for non-rice + NPT for rice), the
increase in SOC was 65–68% at the long-term experiments at Durgapur and Godagari of Rajshahi
district [
18
]. The increase in SOC was equivalent to an additional 3.8–4.2 t of C ha
1
in the soils after
five years under CA (SP for non-rice + NPT for rice with increased residue retention) (see Table 3for
the results at the Godagari, Rajshahi site). Soil N storage also increased with the CA practices, which
also decreased soil bulk density and increased soil porosity [19].
Table 3.
Selected physical and chemical characteristics of the 0–10 cm soil layer of the studied area at
Godagari, Rajshahi after five years of Conservation Agriculture practices (SP + NPT, increased residue
retention, and crop rotation). From [18,19].
Treatments
Characteristics
Bulk density
(g cm3)
Porosity
(%) pH (H2O) Total N
(g kg1)
Total
organic C (t
ha1)
Microbial
Biomass C
(mg kg1)
CT + CP with LR 1.53 a 40.5 d 6.10 0.49 c 6.43 d 93 b
CT + CP with HR 1.46 b 43.1 b 6.40 0.58 b 7.83 c 136 a
SP + NPT with LR 1.50 ab 41.9 c 6.40 0.59 b 9.00 b 84 b
SP + NPT with HR
1.40 c 45.1 a 6.70 0.76 a 10.22 a 142 a
Note: CT, Conventional full tillage for non-rice crops; CP, Conventional puddled soil for rice crops; SP, Strip planted
for non-rice crops; NPT, Non-puddled transplanting of seedlings for rice crops; LR, Low residue (farmers’ practice)
level; HR, Increased residue level; Ns, Non-significant. Values in a column, followed by a common letter are not
significantly different at p< 0.05 by the least significant difference Test.
The research at Rajbari on a light textured soil concluded that the minimum soil disturbance
practices ((SP + NPT) and zero tillage (ZT + NPT)) increased SOC, total N (TN) and extractable sulphur
(S) and zinc (Zn) contents in the uppermost 0–5 cm soil layer [
20
]. The 0–5 cm soil depth was enriched
with SOC and TN content by 24% and 23%, 23% and 18%, and 11% and 9% under ZT + NPT, SP + NPT
and CT + CP practices, respectively, in contrast with the initial values. By contrast, the accumulation of
extractable phosphorus (P), S and Zn followed the sequence ZT + NPT > SP + NPT > CT + CP practice.
The increased residue retention significantly increased SOC, TN, extractable P, potassium (K), S, Zn
and boron (B) contents. Crop establishment and crop residue retention had significant influence on the
soil penetration resistance and soil water content (SWC), but not soil bulk density. The SP + NPT and
HR conserved more SWC and decreased penetration resistance values compared to CT + CP practices
with LR. The SP + NPT practices increased grain yield of rice and lentil and yield of jute fibre, but
Agriculture 2019,9, 5 10 of 17
not the grain yield of wheat [
21
]. Higher crop residue retention increased the yield of jute fibre, rice
and wheat.
Based on average gross margin and BCR, SP + NTP together with increased (50% vs. 20% cereal
crop residue retention) was more profitable for aman rice, jute and wheat production than other crop
establishment and residue retention combinations [
20
]. The study suggests that SP + NPT coupled
with increased crop residue retention is a suitable crop establishment and residue management system
for rice–jute-based cropping to maintain soil fertility, farm profitability and productivity of crops.
Up to Crop 7 in a rice–wheat–mung bean rotation, there was no indication that SP + NPT or
increased crop residue retention altered the N fertilizer requirements for maximum yield of rice or
wheat [
22
]. Research results showed that both NH
4
-N and NO
3
-N levels in standing water were
20–30% higher after CP rice establishment compared to NPT rice systems. This result indicates that
more N loss might occur for the case of CP compared to NPT.
Soil carbon sequestration was higher in SP + NPT together with increased crop residue retention
than those of other treatment combinations. The carbon sequestration was positive and ranged from
35.2 to 288 kg C t
1
of rice production. The NPT of rice can potentially avoid 29% of the CO
2
-eq
emissions occurring with CP of soil under the current low level of crop residue retention [
23
]. For the
aman rice crop, NPT of rice with current crop residue retention decreased life cycle greenhouse gas
emission by 22% relative the CP with the low current crop residue retention [
18
]. While increased
crop residue retention with NPT of rice was not as effective in saving greenhouse gas emissions (it
increased CH
4
emissions) as the current low crop residue retention, it produced greater rice yield and
contributed to greater SOC, decreased bulk density and increased porosity of soil.
2.7. Conservation Agriculture as a Rice-Based System
The feasibility of CA as a rice-based system should be assessed after several years, since CA is a
cropping system change that needs time to fully express the changes in soils and weeds that occur.
In the Bangladeshi studies, the feasibility and benefits of CA are best illustrated by six long-term
experiments, some of which have reached 21 consecutive crops [
24
]. All of them include at least one
aman rice crop per year. Other crops include wheat, mustard, lentil, chickpea, jute, mung bean and
boro rice. The sites are located in different agro-ecosystem zones, with varied climate, soil type, land
type (elevation) and hydrology (Figures 1and 2). Overall, there are consistent findings that NPT rice
in these experiments yielded the same as in CP soil or more. This means that, by using NPT, CA can be
practiced as a system all-year round in the rice-based cropping patterns of Bangladesh and probably
more widely in the EGP.
Transplanting rice seedlings into non-puddled soils with minimum soil disturbance is an
opportunity to expand the adoption of the CA in rice-based cropping systems [
8
]. Manual transplanting
of rice seedlings for both puddled and non-puddled conditions is time consuming, labour intensive and
costly. To introduce mechanized rice seedling transplanting into non-puddled soils, two approaches
were studied, both using transplanters already used for puddled soils. In the first approach, strips
were prepared by VMP in dry or moist (i.e., not-saturated) soil. Then, the field was flooded for 18–24 h
based on soil condition so that the soil in the strips became soften, followed by transplanting of rice
seedlings into the strips by a walk-behind type of rice transplanter [
25
]. Secondly, an experimental
rice transplanter was developed [
25
] for transplanting of rice seedlings into wet non-puddled soils in
a single pass operation, incorporating a narrow strip (3–4 cm width) making mechanism. Detailed
performance results and the construction design of the rice transplanter, modified for making tilled
strips in non-puddled soil, is described in [
26
]. From evaluations of the rice transplanter on a research
farm and on farmers’ fields, mechanised NPT saved 50–70% time and 46–60% fuel for transplanting
of rice seedlings relative to the CP. However, the use of non-puddled rice transplanter reduced fuel
consumption for mechanical transplanting by 10–18%. Overall, in NPT, the non-puddled transplanter
covered more area per day than when operated in CP. Collectively, rice seedling transplanting in NPT
mode gave significantly higher rice grain yield than CP [25,26].
Agriculture 2019,9, 5 11 of 17
In summary, the CA practice increased crop production, largely due to the increased yield of
non-rice crops, and profit, by decreasing cost of crop production (reduced labour, machinery hire and
fuel). While most of the long-term experiments were conducted on farmers’ fields, there are still few
farmer-managed fields where continuous CA practice has occurred for significant lengths of time.
Targeting the early adopters of CA to assess the benefits accrued by farmers in the medium to long
term is therefore a priority for future research.
2.8. Water Balance
Water savings are the key benefit for CA, particularly in rainfed cropping in semi-arid and arid
environments. Water savings are achieved by minimum soil disturbance that slows the loss of soil
water by evaporation. In addition, soil cover by standing or prostrate crop residue slows the rate
of soil water evaporation. The cooler temperatures under retained residue also contribute to slower
evaporation loss of soil water. To date, only limited research has been done on the water savings under
CA in the EGP, and most of this has been under irrigated crops where less irrigation water has been
reported to be adequate for wheat and rice.
The long-term experiments with CA for monsoon rice–wheat–mung bean and monsoon
rice–lentil–boro rice crop rotations on silty clay loam soils at Rajshahi, Bangladesh were used to
estimate irrigated water use [
27
]. Over three years, SP + NPT saved 11–33% of water compared to CT
+ CP. Water productivity of wheat was higher in SP compared to CT in three years. In 2015, water
productivity of wheat was 2.06 and 1.25 g grain kg
1
water for SP and CT, respectively. Similarly, water
productivity of wheat in 2016 and 2017 was the highest (2.32 and 1.95 g grain kg
1
water, respectively)
in SP [27].
2.9. Local Service Providers
Local service providers are widely spread in rural Bangladesh providing a diverse range of
mechanization services (ploughing, transportation, pumping, threshing, and shelling). The LSP are
expected to have a key role in making CA accessible to farmers, in driving the development of the
technology including improvements in the VMP and other planters.
During 2012–2017, up to 50 VMPs that were operating commercially by LSP were monitored
closely to collect business performance data. On average, each VMP covered 6.5 ha during 2012–2013
and increased to 18.9 ha in 2016–2017. During this period, the number of farmers served by each LSP
increased from 31 to 75 [
28
]. In 2017, 18 LSP were selected from Rajshahi, Thakurgaon, Mymensingh
and Rajbari districts for a study of their business model. The study revealed that LSPs effectively
utilized the VMP and 2WT for 4–6 months. They received US$1745 per year as net income. The average
payback period for the VMP purchase was 0.98 years. The annual break-even use of the VMP was
7.8 ha [28].
To select new LSP for VMP sales, Hoque Corporation (HC) targeted clients in project working
hubs who were existing service providers that already owned a 2WT since the tractor is essential to
operate the VMP. These LSPs had the financial means to buy a VMP; they were well known in their
community for selling tillage services; they were business-minded, risk takers who were open to try
new technologies compared to traditional farmers; they had mechanical skill and required minimal
training on VMP operation and maintenance; they already were a trusted source of advice to farmers
in their locality; and they had established linkages with other key stakeholders, namely, extension
agencies, CASPA and local administration of their community. A feature of the current promotion
strategy for the VMP is to engage groups of 25–40 neighbourhood farmers who agree to purchase
planting services of the new LSP. The assurance of planting business is a strong incentive for the new
LSP to commit to a bank loan for VMP purchase.
Agriculture 2019,9, 5 12 of 17
2.10. Commercialization Models Tested
Having established that CA in Bangladesh is feasible and a profitable venture for smallholder
farmers, and that the LSP business is profitable for planting by VMP, the next step was to develop
a commercialisation approach to make VMPs available in the market at an affordable price. The
commercialisation approach being pursued involves the creation of both supply and demand for
CA services including the VMP for planting. Over emphasis on either demand creation or on
supply is unlikely to trigger a breakthrough in commercialisation of the VMP or related planters.
Several manufacturers were reluctant to invest without evidence of demand. On the other hand,
where manufacturers supplied only to bulk orders from project funds there was little feedback from
users on how to improve design and performance of planters and often poor-quality planters were
supplied. Low quality planters hampered initial efforts to develop farmer confidence in planters
and create demand. To create demand, the Conservation Agriculture Project trained over 300 LSPs,
technicians from the National Agricultural Research and Extension System, NGOs, the private sector
and local mechanics in the manufacturing factory or repair workshops. Over 6600 farmers hired/used
VMP/VSSD to sow lentil, mustard, mung bean, sesame, jute, wheat, maize, rice, chickpea, etc. on more
than 1500 ha. This illustrates the level of demand already created in the six study areas (Figure 1).
Of the five manufacturers provided with designs for the VMP, only Hoque Corporation has
taken the initiative to develop the market for VMPs by setting up distribution and sales networks and
developing a supply chain to manufacture or import component parts, maintain quality control of
component parts and the VMP, seek orders and deliver on time, continuously upgrade designs for user
satisfaction and provide after sales service. An important component of the commercialisation model
developed with Hoque Corporation is the training of LSPs. New LSPs are provided with repeated
training sessions in the operation of the VMP and related services such as crop production, agronomy
and weed during the first 1–2 years after purchasing the VMP. Experienced operators are engaged to
provide training and to mentor the new LSPs.
2.11. Improved Adoption of CA Led by A Service Provider Network
Elsewhere in the world where CA has been widely adopted by farmers, it was supported
by partnerships between farmer groups and other key stakeholders: manufacturers of machinery,
extension officers, researchers, and agricultural input suppliers (e.g. herbicide suppliers) [
29
]. In the
EGP and Bangladesh in particular, LSPs are an additional stakeholder that need to be involved in
the partnership, since LSPs are widespread and already provide ploughing, pumping and threshing
services on a custom-hire basis to most smallholder farms. To create partnerships between LSPs and
farmers, we identified 224 farmers’ groups working in nine districts (with a membership of 9800 farm
families) and established the Conservation Agriculture Service Providers Association (CASPA). In
collaboration with the CASPA and Department of Agricultural Extension (DAE), the Conservation
Agriculture project: established 3414 farmers’ participatory demonstrations (farmers contributed most
of the inputs, and the Conservation Agriculture project provided only the critical inputs) on minimum
tillage, residue retention, crop rotation, weed management, NPT rice establishment, etc.; trained
9800 farm families on CA and integrated weed management practices and safe use of herbicides;
and organized 116 field days, focus group discussion sessions and promotional meetings that reached
10,894 farmers most of whom practising CA or one of its principles: crop residue retention, crop rotation
(e.g., lentil adoption in Rajshahi and mustard between two rice crops at Mymensingh), SP systems for
non-rice crops and NPT for rice establishment.
From initial on-farm studies, we estimated that farmers who adopted VMP and CA technologies
have gained up to 38%, 8% and 6% more grain yield of lentil, mung bean and wheat, respectively,
over conventional practice [
30
]. The CA adopters obtained higher net return of US$366, US$93 and
US$195 ha
1
for lentil, mung bean, and wheat, respectively, over conventional methods. It was
estimated the profit from NPT rice compared to CP systems was US$105–127 ha1[31].
Agriculture 2019,9, 5 13 of 17
Farmers that used CA in a three-crop rotation within a year could achieve 29%, 54%, and 14%
greater net profit (additional income of US$372 year
1
for a 1 ha farm) with monsoon rice, wheat, and
mung bean crops, respectively, compared to farmers practicing CT + CP [
32
]. Based on the above yield
increases and cost savings, we estimated that the annual potential gain from 2.5% adoption of CA
and mechanized planting in Bangladesh (this is about the current level of CA adoption across Asia) is
US$20 million (base year 2013–2014) from the additional 23,500 t of aman rice, 43,000 t of boro rice,
2000 t of wheat and 5000 t of maize grain yield plus the value of cost savings to farmers. Additional
value would be created by LSPs, manufacturers and others in the value chain (mechanics, dealers, and
traders). Based on the potential yield increases and costs savings to farmers, adoption of CA and the
VMP planting services by only 2.5% of all farmers in Bangladesh would directly generate an additional
US$21–38 million per year [30].
In 2017, a study was undertaken to assess adoption levels and impacts on farm businesses [
28
].
In Durgapur Upazilla of Rajshahi district, where a concentration of effort on VMP promotion and
extension of CA has occurred in the last fie years, the adoption of CA in 2016–2017 rabi season was 4.5%
of the total crop area. In three blocks, the CA planting reached 10–16% of all rabi season crops. Hence,
there is evidence of early adoption by farmers where there have been programmes to build farmer
awareness, confidence in the technology and the availability of the planters and LSP to offer planting
services to farmers on a custom hiring basis [
30
]. Average benefits from the farm mechanization and
CA adoption have been estimated from a study of 135 farmers as follows: 34% labor saving, 31% less
seed required, 6% fertilizers saving, 32% pesticide cost saving leading to up to 10% lower production
cost for lentil, mustard, maize and wheat [
30
]. There was a yield increase of 28% for lentil, 19% for
mustard and 6% for wheat by farmers who adopted CA planting using the VMP, and profit increases
by 47% for lentil, 55% for maize, 46% for mustard and 76% for wheat due to adoption of CA planting
using VMP [28].
To create demand for the VMP, HC arranged widespread demonstrations of VMP operation
and on-farm demonstration of crop performances by LSP for establishing wheat, onion, garlic, lentil,
chickpea, mung bean, jute, etc. in study areas. For initial demand creation from new LSPs, the
Conservation Agriculture project provided 50% and 25% price support for VMP in 2015 and 2016,
respectively, but none in 2017. The Conservation Agriculture project activities created confidence by
farmers, LSPs, and involved stakeholders (e.g., DAE, Barind Multipurpose Development Authority,
National Bank Ltd., etc.) in VMP adoption and commercialization. Working with multi-stakeholders
appears to be critically important for commercialization of this new planting machinery. The LSPs
and farmers were cautious to invest money for new farm implements based on previous experiences
after purchasing implements. Involvement of universities (e.g., Bangladesh Agricultural University
and Murdoch University), extension agencies (e.g., DAE) and coordination through Conservation
Agriculture project has built the trust among the LSPs and farmers to buy and adopt the VMP.
Based on feedback from farmers’ on their requirements, ongoing modification of the VMP since
2015 has significantly reduced the market price and weight of the planter and improved weight
balancing, while maintaining assurance of high-quality production. Seed meters now supplied with
the VMP regulate the seed rate without field calibration. In addition, significant improvement was
made on the shank of furrow openers to increase the strength, while the seed-boot and fertilizer-orifice
of the furrow opener were modified to minimize seed and fertilizer contact. This improvement has
strengthened confidence of LSPs and farmers in the use and performance of the VMP.
2.12. A Roadmap for CA in the EGP
The research and development to date describes a feasible CA practice for rice-based cropping
systems in Bangladesh. However, to advance the development and adoption of CA in the EGP, we
make the following recommendations:
Governments adopt a CA policy for implementation by their agricultural extension, research
and university sectors. Through respective Departments of Agricultural Extension, Governments
Agriculture 2019,9, 5 14 of 17
should develop mass promotional activities including publicity and awareness building on CA.
Laws, regulations and policies need to be reviewed to identify and amend those that hamper the
profitable adoption of CA by farmers.
Governments engage with the private sector and farmers’ organisations to establish Centres
for Conservation Agriculture Research and Development to represent, coordinate and guide
the CA programmes of research, development and extension (R, D & E) agencies, agricultural
universities and research funding agencies. Governments and other fund providers and investors
should allocate funding and work with the Centres to conduct R, D & E on CA, to adapt it to the
conditions and requirements of EGP agriculture.
Governments and the private sector work with and strengthen CA farmers’ associations to
promote adoption and local adaptation of CA. Governments may need to remove bottlenecks for
profitable engagement by the private sector in promoting CA.
Protagonists for CA work with finance institutions to establish accessible, interest-free or low
interest finance for CA-related machinery manufacturers, LSPs, and users and to apply incentives
to LSP and farmers to take up CA practices.
For research, extension and education in the EGP on CA, we recommend the priorities are to:
Set up and maintain long term CA experiments on key soils and agro-ecological regions to assess
system productivity, improvement in soil properties over time, and identify emerging trends that
affect weed, pest and disease control. In addition, there should be support for farmer-managed
fields where continuous CA practice has occurred for three years or more. Targeting the early
adopters of CA to assess the benefits accrued by farmers after 3–5 years is therefore a priority for
future research.
Continue to improve non-puddled rice establishment, including defining the domain of rice
production in the EGP where it is best suited.
Continue to improve ZT/SP seed drills for direct seeding of rice and reliable establishment of
other crops and weed control in different field types, hydrological regimes and seasons with the
aim of defining the domains where forms of CA technology are reliable for farmers to adopt.
Where adoption occurs over a significant proportion of the landscape, undertake landscape-scale
water balance studies to define the real effects of CA practice on groundwater levels and
recharge rates.
National programmes of on-farm adaptive experiments to develop improved local and regional
variations on best practice for CA. In particular there is a need for recommendations on row
spacing, seed rate, seedling depth, etc for CA planting of the major crops involving SP or ZT and
suitable levels of crop residue retention.
Determine fertiliser management requirements for crops under CA management.
Develop and promote to farmers integrated weed management approaches to reduce reliance on
herbicides for weed control and minimise the development of herbicide resistance in weed species.
Routine screening of cultivars of major crops for vigour and yield in CA planting (SP and retained
crop residues). In addition, for the major crops grown under CA, identify key traits required
for CA planting and develop screening programmes to select better-adapted cultivars. Routine
screening of new cultivars of major crops (rice, wheat, maize, jute, mung bean, lentil, mustard,
and sunflower) needs to be instituted to identify cultivar variations in phytotoxicity and residual
effects by herbicides. Since herbicides are rapidly becoming the weed control practice of choice
by farmers, this recommendation is not specific to CA, but applies to conventional tillage as
well. There may well be differences in phytotoxicity though between CA with minimum soil
disturbance and residue retention and conventional tillage.
Develop second generation planters that are tested by LSPs to identify faults and limitations for
crop establishment performance under more diverse soil and climatic conditions. Pilot studies
Agriculture 2019,9, 5 15 of 17
should also begin on four-wheel tractor niches for CA in the EGP. This will involve initial studies
on best bet planters for 20–30 and 40–60 horsepower tractors.
3. Summary and Conclusions
Research and development in Bangladesh have developed effective CA practices for smallholder
farms in the EGP using minimum soil disturbing implements mounted on 2WTs. The key outcomes
are new knowledge developed on: (i) effective strip planting using the VMP [
4
6
]; (ii) planting
machinery development and performance testing in the small fields using 2WTs [
4
,
9
]; (iii) agronomy
for mechanised seeding with minimum soil disturbance and residue retention [
5
,
6
]; (iv) weed
dynamics and weed management under CA [
11
16
,
33
]; (v) crop rotation effects on soils and
weeds [
33
,
34
]; (vi) mechanised transplanting of NPT rice [
24
,
25
]; (vii) soil improvement under
CA [
17
22
]; (viii) decreased greenhouse gas emissions under CA [
23
]; (ix) increased profit from
CA-based SP + NPT rice in farmers’ fields [
8
]; (x) water balance [
27
], which showed that wheat under
CA (SP and increased residue retained) required 11–33% less irrigation water than the convention
practices; and (xi) commercialisation models for sales of planters to LSP [
31
]. Based on the evidence
presented, there should now be sufficient confidence for more widespread demonstrations across
different agro-ecosystems in the EIP and for programmes to engage the private sector and farmers in
adoption and out-scaling of CA for smallholder rice-based crop production in the EGP.
Author Contributions:
R.W.B. helped with design of field evaluation trials, data analysis, and led the manuscript
writing. M.E.H. led the design and fabrication of planters, and contributed to research, data collection and
manuscript preparation. M.J. supervised soil research and one of the long-term experiments reviewed. M.M.R.
supervised research on weed control. M.B. supervised weed seed bank research. M.A.M.M. designed, led and
wrote up the surveys of on-farm profitability of CA and the LSP business models. M.A.I. set up two long-term
experiments on CA as part of his PhD studies. M.A.H. conducted PhD research on mechanized transplanting
of non-puddled rice. N.S. conducted PhD research and set up a long-term experiment on CA. T.Z. conducted
PhD research on weed control for CA. M.M.H. conducted PhD research on weed control and CA effects on weed
seedbanks. M.K.A. conducted PhD studies on greenhouse gas emissions and life cycle analysis of the CA practices.
M.N.H.M. conducted PhD studies on water balance under CA.
Funding:
This research was funded by the Australian Centre for International Agricultural Research (ACIAR:
Project LWR/2012/080).
Acknowledgments:
The authors gratefully acknowledge all professors, researchers, and students who were
involved in this project. The authors also acknowledge the LSPs who provided VMP and VSSD contract planting
services and helped with data collection from farmers’ fields.
Conflicts of Interest: The authors declare no conflict of interest.
References
1.
Bangladesh Population (LIVE). Available online: www.worldometers.info/world-population/bangladesh-
population/ (accessed on 20 October 2018).
2.
Bangladesh Bureau of Statistics. Statistical Yearbook of Bangladesh—2013; Bangladesh Bureau of Statistics,
Ministry of Planning, Government of the People’s Republic of Bangladesh: Dhaka, Bangladesh, 2011.
3.
Johansen, C.J.; Haque, M.E.; Bell, R.W.; Thierfelder, C.; Esdaile, R.J. Conservation agriculture for small holder
rainfed farming: Opportunities and constraints of new mechanized seeding systems. Field Crop. Res.
2012
,
132, 18–32. [CrossRef]
4.
Haque, M.E.; Bell, R.W.; Islam, A.K.M.S.; Sayre, K.D.; Hossain, M.M. An innovative Versatile Multi-crop
Planter for crop establishment using two-wheel tractors. Agric. Mech. Asia Afr. Lat. Am. 2017,48, 33–37.
5.
Bell, R.W.; Haque, M.E.; Johansen, C.; Vance, W.; Kabir, M.E.; Musa, M.A.; Mia, M.N.N.; Neogi, M.G.;
Islam, M.A. Mechanised minimum tillage establishment and yield of diverse crops in paddy fields using
a two-wheel tractor-mounted planter suitable for smallholder cropping. Exp. Agric.
2017
,54, 755–773.
[CrossRef]
6.
Vance, W.H.; Bell, R.W.; Johansen, C.J.; Haque, M.E.; Musa, M.A.; Shahidullah, A.K.M.; Mia, N.N. Optimum
time of sowing for rainfed winter chickpea with one-pass mechanised row-sowing: An example for
small-holder farms in north-west Bangladesh. Crop Pasture Sci. 2014,65, 602–613. [CrossRef]
Agriculture 2019,9, 5 16 of 17
7.
Bangladesh Bureau of Statistics. Statistical Pocketbook of Bangladesh—2013; Bangladesh Bureau of Statistics,
Ministry of Planning, Government of the People’s Republic of Bangladesh: Dhaka, Bangladesh, 2013.
8.
Haque, M.E.; Bell, R.W.; Islam, M.A.; Rahman, M.A. Minimum tillage unpuddled transplanting: An
alternative crop establishment strategy for rice in conservation agriculture cropping systems. Field Crop. Res.
2016,185, 31–39. [CrossRef]
9.
Haque, M.E.; Bell, R.W.; Kassam, A.; Mia, M.N.N. Versatile Strip Seed Drill: A 2-wheel tractor-based
option for smallholders to implement Conservation Agriculture in Asia and Africa. Environments
2016
,3, 1.
[CrossRef]
10.
Haque, M.E.; Bell, R.W. Is conservation agriculture increasing herbicide uses? A Bangladesh case. In
Proceedings of the 7th World Congress of Conservation Agriculture, Rosario, Argentina, 1–4 August 2017;
Bartz, M., Llanillo, R.F., Ralisch, R., Eds.; Murdoch University: Perth, Australia, 2017; p. 204.
11.
Zahan, T.; Rahman, M.M.; Begum, M.; Bell, R.W.; Khan, A.S.M.M.R. Broadleaved weed management in
wheat with post-emergence herbicides under strip tillage system. In Proceedings of the 2nd Conference
on Conservation Agriculture for Smallholders (CASH-II), Mymensingh, Bangladesh, 14–16 February 2017;
Haque, M.E., Bell, R.W., Vance, W.H., Eds.; Murdoch University: Perth, Australia, 2017; pp. 123–125.
12.
Zahan, T.; Rahman, M.M.; Hashem, A. Growth and yield response of transplanted aman rice varieties to
herbicides in strip tilled unpuddled soil. In Proceedings of the 2nd Conference on Conservation Agriculture
for Smallholders (CASH-II), Mymensingh, Bangladesh, 14–16 February 2017; Haque, M.E., Bell, R.W.,
Vance, W.H., Eds.; Murdoch University: Perth, Australia, 2017; pp. 48–49.
13.
Hossain, M.M.; Begum, M.; Rahman, M.M.; Hashem, A.; Bell, R.W.; Haque, M.E. Weed seed bank dynamics
in long term trials of conservation agriculture. In Proceedings of the 2nd Conference on Conservation
Agriculture for Smallholders (CASH-II), Mymensingh, Bangladesh, 14–16 February 2017; Haque, M.E.,
Bell, R.W., Wendy, W.H., Eds.; Murdoch University: Perth, Australia, 2017; pp. 41–43.
14.
Rahman, M.M.; Zahan, T. Tolerance of rice varieties to higher rates of two post-emergence herbicides under
strip tilled non-puddled transplanted establishment. In Proceedings of the 2nd Conference on Conservation
Agriculture for Smallholders (CASH-II), Mymensingh, Bangladesh, 14–16 February 2017; Haque, M.E.,
Bell, R.W., Vance, W.H., Eds.; Murdoch University: Perth, Australia, 2017; pp. 44–45.
15.
Zahan, T.; Rahman, M.M.; Begum, M. Residual effect of herbicides applied in unpuddled transplanted aman
rice on the succeeding crops assessed by bioassay technique. Bangladesh Agron. J.
2016
,19, 95–103. [CrossRef]
16.
Zahan, T.; Hashem, A.; Rahman, M.M.; Bell, R.W.; Begum, M. Efficacy of herbicides in non-puddled
transplanted rice under conservation agriculture systems and their effect on establishment of the succeeding
crops. Acta Sci. Malays. 2018,2, 17–25. [CrossRef]
17.
Islam, M.A. Conservation Agriculture: Its Effects on Crop and Soil in Rice-Based Cropping Systems in
Bangladesh. Ph.D. Thesis, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia,
2017; p. 365.
18.
Alam, M.K.; Bell, R.W.; Haque, M.E.; Kader, M.A. Minimum soil disturbance and increased residue retention
increase soil carbon in rice-based cropping systems on the Eastern Gangetic Plain. Soil Tillage Res.
2018
,183,
28–41. [CrossRef]
19. Alam, M.K. Bangladesh Agricultural Research Institute: Gazipur, Bangladesh, 2018. Unpublished work.
20.
Salahin, N.; Jahiruddin, M.; Islam, M.R.; Bell, R.W.; Haque, M.E.; Alam, M.K. Changes in soil organic matter,
plant nutrients and system productivity under conservation agricultural practices in the rice-jute cropping
system. In Proceedings of the 2nd Conference on Conservation Agriculture for Smallholders (CASH-II),
Mymensingh, Bangladesh, 14–16 February 2017; Haque, M.E., Bell, R.W., Wendy, W.H., Eds.; Murdoch
University: Perth, Australia, 2017; pp. 117–119.
21.
Salahin, N. Influence of Minimum Tillage and Crop Residue Retention on Soil Organic Matter, Nutrient
Content and Crop Productivity in the Rice-Jute System. Ph.D. Thesis, Department of Soil Science, Bangladesh
Agricultural University, Mymensingh, Bangladesh, 2017; p. 246.
22.
Jahiruddin, M.; Hossain, R.; Paul, T.; Islam, M.R.; Kader, M.A.; Haque, M.E.; Bell, R.W. Strip tillage
with residue retention increases soil organic carbon, nitrogen requirement and system productivity of
a rice-wheat-mungbean cropping system. In Proceedings of the 2nd Conference on Conservation Agriculture
for Smallholders (CASH-II), Mymensingh, Bangladesh, 14–16 February 2017; Haque, M.E., Bell, R.W.,
Wendy, W.H., Eds.; Murdoch University: Perth, Australia, 2017; pp. 12–13.
Agriculture 2019,9, 5 17 of 17
23.
Alam, M.K.; Biswas, W.K.; Bell, R.W. Greenhouse gas implications of novel and conventional rice production
technologies in the Eastern-Gangetic plains. J. Clean. Prod. 2016,112, 3977–3987. [CrossRef]
24.
Haque, M.E.; Bell, R.W.; Islam, M.A.; Alam, M.K.; Mahmud, M.N.H.; Jahiruddin, M. Long-term impact of
smallholders’ Conservation Agriculture in rainfed and irrigated systems. In Proceedings of the 2nd African
Congress of Conservation Agriculture, Johannesburg, South Africa, 9–12 October 2018; African Tillage
Network: Nairobi, Kenya, 2018; pp. 197–200.
25.
Hossen, M.A.; Hossain, M.M.; Haque, M.E.; Bell, R.W. Transplanting into non-puddled soils with a
small-scale mechanical transplanter reduced fuel, labour and irrigation water requirements for rice (Oryza
sativa L.) establishment and increased yield. Field Crops Research. Field Crop. Res.
2018
,225, 141–151.
[CrossRef]
26.
Hossen, M.A. Development of Rice Transplanter for Unpuddled Condition. Ph.D. Thesis, Department of
Farm Power and Engineering, Bangladesh Agricultural University, Mymensingh, Bangladesh, 2017; p. 312.
27.
Mahmud, M.N.H.; Bell, R.W.; Vance, W. Strip planting increases yield and water productivity of wheat
(Triticum aestivum) in Northwest Bangladesh. In Proceedings of the International Conference on Agri Biotech
and Environmental Engineering, San Antonio, TX, USA, 11–12 September 2017; p. 32.
28.
Miah, M.A.M.; Rashid, M.A.; Haque, M.E.; Bell, R.W. Adoption Impacts of Conservation Agriculture Technologies
at Farm Level in Bangladesh; Agricultural Economics Division, Bangladesh Agricultural Research Institute
and Murdoch University: Murdoch, Australia, 2017; p. 47.
29.
Pieri, C.; Evers, G.; Landers, J.; O’Connell, P.; Terry, E. No-Till Farming for Sustainable Rural Development;
Agriculture and Rural Development Working Paper; FAO: Rome, Italy, 2002.
30.
Haque, M.E.; Bell, R.W.; Jahiruddin, M.; Hossain, M.M.; Rahman, M.M.; Begum, M.; Hossen, M.A.;
Salahin, N.; Zahan, T.; Hossain, M.M.; et al. Manual for Smallholders’ Conservation Agriculture in Rice-based
Systems; Murdoch University: Perth, Australia, 2018; p. 108.
31.
Haque, M.E.; Bell, R.W.; Menon, R.K.; Hoque, M.M.; Hossain, M.M.; Rahman, M.A.; Hossain, M.I.;
Chowdhury, A.H.; Mortuza, M.A.H. Commercialization approach for Versatile Multi-Crop Planter: Lessons
learnt. In Proceedings of the 2nd Conference on Conservation Agriculture for Smallholders (CASH-II),
Mymensingh, Bangladesh, 14–16 February 2017; Haque, M.E., Bell, R.W., Vance, W.H., Eds.; Murdoch
University: Perth, Australia, 2017; pp. 65–68.
32.
Haque, M.E.; Bell, R.W.; Vance, W.; Mia, N.N. Designing Intensive Crop Sequences for Conservation
Agriculture Using Mechanized Planters on Two-Wheel Tractors. In Proceedings of the 4th International
Symposium for Farming Systems Design, Lanzhou, China, 19–22 August 2013; Chen, F., Gao, W., Eds.;
Gansu Science and Technology Press: Lanzhou, China, 2013; pp. 251–252.
33.
Hossain, M.M.; Begum, M.; Hashem, A.; Rahman, M.M.; Bell, R.W.; Haque, M.E. Yield response of mustard
as influenced by weed management practice under conservation agriculture system. Bangladesh J. Weed Sci.
2014,4, 87–92.
34.
Hossain, M.M.; Begum, M.; Hashem, A.; Rahman, M.M.; Bell, R.W.; Haque, M.E. Yield response of
transplanted aman rice to weed management practice under conservation agriculture system. In Proceedings
of the 25th Conference of Asian-Pacific Weed Science Society, Hyderabad, India, 13–16 October 2015; Indian
Society of Weed Science: Jabalpur, India, 2015; Volume 3, p. 594.
©
2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) license (http://creativecommons.org/licenses/by/4.0/).
... By slowing the breakdown of plant residues, this practice can reduce the release of mineralized inorganic forms of plant nutrients in the soil [1,2]. In Bangladesh's rice-based intensive cropping systems, planting for upland crops following strip tillage and non-puddled transplanting for rice crop establishment have recently been introduced [3,4]. Considering production, economic return, and soil health, the novel crop-establishing approaches performed almost as well as or better than the conventional practices [4,5]. ...
... In Bangladesh's rice-based intensive cropping systems, planting for upland crops following strip tillage and non-puddled transplanting for rice crop establishment have recently been introduced [3,4]. Considering production, economic return, and soil health, the novel crop-establishing approaches performed almost as well as or better than the conventional practices [4,5]. If additional management practices can be established in line with CA practices, the performance of CA practices can be increased [5]. ...
... None of the growth parameters, yield-contributing characters, and yields of irrigated rice and monsoon rice in the current study were varied due to different tillage systems. The results of this study were in agreement with the previous study by Bell et al. [4], who found modification of tillage systems, i.e., strip tillage for upland crops and non-puddled transplanting systems for rice (ST/NP) perform equal to or better than conventional systems. Islam [9], Haque et al. [3], and Salahin [37] also found similar yield results with ST/NP compared to CT practice (deep tillage for upland crops and puddling for rice crops). ...
Article
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In intensive crop production systems, sustainable agricultural development strives to find the balance between productivity and environmental impact. To reduce the N fertilizer-associated environmental risks of intensive cropping, sound agronomic and environmentally acceptable management practices are urgently needed. To attain high yields, improve soil health, and ensure economic return and N usage efficiency in conservation-based intensive agriculture, N management must be optimized, which has not yet been studied systematically in the mustard-boro rice-aman rice cropping pattern. During 2016/17, 2017/18, and 2018/19 cropping seasons in Bangladesh, cropping system experiments were conducted to investigate the interactive effects of tillage practices and nitrogen fertilizer rates on soil characteristics, crop productivity, and profitability under conservation agriculture (CA) systems. The trial featured two tillage systems: (i) conventional tillage (CT) and (ii) strip-tillage (ST). It also used three doses of N fertilizer: N1: 75% of the recommended N fertilizer dose (RND); N2: 100% of the RND; and N3: 125% of the RND. Each crop’s experiment was set up in a split-plot design with three replications, with the main plot assigned tillage practices and the sub-plot assigned nitrogen fertilizer rates. For rice, neither the tillage systems nor the interactions between the tillage systems and N levels affected any of the growth parameters, yield, and yield components, but the N levels did. Across the tillage systems, the rice grain and straw yield were similar for the N levels of 100% RND and 125% RND, which were significantly higher than the N level of 75% RND. In mustard, the highest seed yield was recorded from the tillage system ST, with an N level of 125% RND, which was at par with the tillage system ST with 100% RND and CT with 125% RND. The highest system rice equivalent yield (SREY, 14.9 to 15.8 t ha−1 ) was recorded from the tillage system ST, with an N level of 125% RND, which was at par with the same tillage system with an N level of 100% RND. The soil penetration and bulk density (BD) were higher for the CT than the ST, but soil organic matter (OM), total nitrogen (TN), phosphorus (P), potassium (K), and boron (B) content were higher for the tillage system ST than the CT. Across N levels, the tillage system CT had a 2–4% higher production cost than the ST. Total production cost increased as N levels increased across all tillage systems. The tillage system ST with an N level of 125% RND had the highest system gross return and net profit, which was at par with the same tillage system with 100% RND. This study suggested that farmers should apply slightly higher N for the mustard-boro-aman rice systems for the first couple of years when commencing CA; however, after a few years of consistent CA practice, the N rate may be reduced.
... Adoption of Conservation Agriculture (CA) practices by farmers in the intensive rice-based triple-cropping systems on the EGP is increasing (Bell et al., 2019;Haque et al., 2016;Taneja et al., 2014) and the CA practices not only increase crop yield but also mitigate the effects of rice-based cropping systems on greenhouse gas emission (Alam et al., 2016). In addition, minimal soil disturbance and increased residue retention practiced for 5 years increased soil organic carbon (SOC) (0-10 cm soil depth) by 68% in intensive triple-cropping, rice-based cropping systems on the Grey Terrace soil of the EGP (Alam et al., 2018). ...
... In our study, after 8 years, total S, organic S, available S, water soluble S, total S stock, total SOC stock and total N stock were about 2%, 5%, 8%, 9%, 5%, 8% and 13% higher on SP than with CT, respectively, showing a positive long term effect from minimum soil disturbance in the High Barind Tract soils of Bangladesh. Strip planting is crop establishment practice being adopted in Bangladesh involving minimum soil disturbance (Bell et al., 2019) by which increased SOC is sequestered in soil (Islam et al., 2022;Alam et al., 2018). Since C:S ratio of SOM is fairly stable, increased SOC sequestration will sequester additional S in soil. ...
... In our study, we found higher content of S pools in soil in SP than CT which may alleviate the S deficiency in crops (data not shown). On the other hand, increased crop yield under SP practice (Bell et al., 2019) may increase demand for S fertilizer required for the crop production. ...
Article
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Long term depletion of sulfur (S) in soils is common in many cropping systems globally, and especially in intensive, rice-based rotations in Asia. We hypothesized that Conservation Agriculture (CA) practices (minimal soil disturbance and crop residue retention) will increase S in soils primarily through changes in soil organic carbon (SOC). A long term experiment was sampled after 24 crops of continuous practice of (A) contrasting soil disturbance (strip planting = SP and conventional tillage = CT) and (B) two levels of crop residue retention (low residue = LR and high residue = HR). Sulfur fractions and dynamics in soil at five depths (0-5, 5-15, 15-30, 30-45 and 45-60 cm) along with bulk density (BD), pH, SOC, total nitrogen (TN) and extractable nutrients were determined. Levels of total S (584-668 mg kg − 1), organic S (50.0-153 mg kg − 1), available S (7.9-21.6 mg kg − 1) and water soluble S (6.0-17.0 mg kg − 1) were the highest in SP with HR (P < 0.05), while inorganic S (505-533 mg kg − 1) and adsorbed S (2.3-4.4 mg kg − 1) were significantly higher (P < 0.05) in HR plots irrespective of tillage systems at 0-30 cm soil depth. All the S fractions were positively and strongly correlated with SOC and except for inorganic and adsorbed S, all other S fractions were positively correlated with TN, extractable P, Zn, B and Fe. All S fractions were negatively correlated with BD. Inorganic S was the dominant S fraction but highly significant and positive correlations of available S with organic S (r = 0.92) and water-soluble S (r = 0.92) suggests these two fractions were the main sources of plant available S. This study suggests that both minimal soil disturbance and increased crop residue retention, core components of CA, increased S pools in soils primarily due to increased SOC sequestration.
... Conservation agriculture (CA), which integrates minimum soil disturbance, crop residue retention and diversified crop rotation (Johansen et al., 2012), has been evaluated in rice-based systems in several eco-regions of the Indo-Gangetic Plain (IGP), which extends from Pakistan in the west across India and into Bangladesh in the east (Bhatt and Kukal, 2017;Jat et al., 2014), and it has been advocated in diverse agro-ecological zones for smallholders in South Asia (Jat et al., 2020;Joshi et al., 2021). Many positive benefits are claimed for CA such as increased crop yield (Choudhury et al., 2014;Saha and Ghosh, 2013) with reduced labour, fuel and irrigation water requirements (Hossen et al., 2018), which result in lower production costs and improved farm profit (Bell et al., 2019;Haque et al., 2016). Consequently, adoption of CA for growing all crops in rice-based systems of the IGP has been increased over the last decade (Hobbs et al., 2017). ...
... They should be farmer managed but extensively monitored to establish relationships across soil types, rainfall patterns, cropping systems, market opportunities, etc. Such evaluations are underway in a Conservation Agriculture Project for addressing various constraints to improve the adoption of CA in different rice-based cropping systems in EIGP (Bell et al., 2019). ...
Article
Sustaining productivity of the rice-based cropping systems in the Eastern Indo-Gangetic Plain (EIGP) requires practices to reverse declining soil fertility resulting from excessive tillage and crop residue removal, while decreasing production costs and increasing farm profits. We hypothesize that the adoption of conservation agriculture (CA), involving minimum tillage, crop residue retention and crop rotation, can address most of these challenges. Therefore, the effects of crop establishment methods – strip planting (SP), bed planting (BP) and conventional tillage (CT); and levels of crop residue retention – high residue (HR) and low residue (LR) on individual crop yield, system yield and profitability were evaluated in a split-plot design over three cropping seasons in two field experiments (Alipur and Digram sites) with contrasting crops and soil types in the EIGP. The SP and BP of non-rice crops were rotated with non-puddled rice establishment; CT of non-rice crops was rotated with puddled transplanted rice. In the legume-dominated system (rice-lentil-mung bean), lentil yields were similar in SP and CT, while lower in BP in crop season 1. A positive effect of high residue over low residue was apparent by crop season 2 and persisted in crop season 3. In crop season 3, the lentil yield increased by 18–23% in SP and BP compared to CT. In the cereal-dominated system (rice-wheat-mung bean), significant yield increases of wheat in SP and BP (7–10%) over CT, and of HR (1–3%) over LR, were detected by crop season 3 but not before. Rice yields under CA practices (non-puddled and HR) were comparable with CT (puddled and LR) in both systems. Improved yield of lentil and wheat with CA was correlated with higher soil water content. The net income of SP increased by 25–28% for dry season crops as compared to CT and was equal with CT for rice cropping systems. Conservation agriculture practices provide opportunities for enhancing crop yield and profitability in intensive rice-based systems of the EIGP of Bangladesh.
... Studies have also demonstrated that reductions of GHG emissions from CA compared to conventional tillage (CT) (Govaerts et al., 2009;Aryal et al., 2016;Alam et al., 2019a;Alam et al., 2019b). Haque et al. (2016); Bell et al. (2019), and Islam et al. (2013) reported that compared to conventional repetitive tillage, fuel consumption could be reduced 2-3 fold where farmers use strip tillage as a CA practice in northwestern Bangladesh. Haque et al. (2016); Bell et al. (2019), and Hossen et al. (2018) also suggested that unpuddled transplanted rice, in which fields are not wet tilled prior to crop establishment, can also decrease time and fuel consumption by 50-70%, while also boosting energy productivity (EP) by 8-12%, relative to CT. Gathala et al. (2016;2020) demonstrated that energy use was significantly lower and energy-use efficiency (EUE) higher for maize planted with strip tillage compared to CT in a range of rice-based cropping sequences across India, Nepal, and in northwestern Bangladesh. ...
... Haque et al. (2016); Bell et al. (2019), and Islam et al. (2013) reported that compared to conventional repetitive tillage, fuel consumption could be reduced 2-3 fold where farmers use strip tillage as a CA practice in northwestern Bangladesh. Haque et al. (2016); Bell et al. (2019), and Hossen et al. (2018) also suggested that unpuddled transplanted rice, in which fields are not wet tilled prior to crop establishment, can also decrease time and fuel consumption by 50-70%, while also boosting energy productivity (EP) by 8-12%, relative to CT. Gathala et al. (2016;2020) demonstrated that energy use was significantly lower and energy-use efficiency (EUE) higher for maize planted with strip tillage compared to CT in a range of rice-based cropping sequences across India, Nepal, and in northwestern Bangladesh. In addition, Alam et al. (2015) and Laik et al. (2014) reported that intensive tillage practices in central Bangladesh and northeastern India, respectively, used greater amounts of total energy compared to production under unpuddled rice transplanting in which fields were not wet tilled. ...
Article
Full-text available
While numerous studies have documented the benefits of conservation agriculture (CA) in South Asia, most focus on favorable environments where farmers have reliable access to energy supporting irrigation and inputs. The performance of CA in South Asia’s under-developed coastal environments is comparatively understudied. In these environments, farmers are increasingly interested in growing a second crop to meet food security and income generation objectives in rotation following the predominant monsoon season rice crop, though labor, energy costs, and investment constraints limit their ability to do so. We hypothesized that rotating rice ( Oryza sativa ) with maize ( Zea mays ) using conservation agriculture, or CA (i.e., strip-tilled maize followed by unpuddled transplanted rice), or seasonally alternating tillage (SAT, i.e., strip-tilled maize followed by fully-tilled, puddled rice with residues retained across rotations) would reduce costs and energy use, increase energy-use efficiency, and reduce yield-scaled CO 2 -eq emissions (YSE) and total global warming potential (GWP), compared to farmers’ own practices (FP) and conventional full-tillage (CT) under the same rotation in Bangladesh’s coastal region. Starting with winter maize followed by summer rice, we evaluated four tillage and crop establishment treatments in farmer-managed experiments in partially irrigated and rainfed environments over three years in 35 farmer’s fields across Bangladesh’s coastal districts. Treatments included FP, CT, complete CA, and SAT under a rice-maize rotation. Across years, the full suite of CA practices and SAT were significantly more energy-efficient and energy-productive than FP or CT. The order of YSE in rice was CA< CT or FP < SAT while in maize, it was CA or SAT < FP < CT. Across environments, CA and SAT resulted in 15-18% higher yield at the cropping systems level (maize and rice yields combined) and 26-40% less manual labor than CT or FP. CA and SAT also reduced by 1-12% and 33-35% total production costs respective to CT and FP. This was associated with 13-17% greater grain energy output in CA and SAT, and 2-18% lower YSE, compared to CT or FP. While our data suggest that both CA and SAT can result in a range of positive agronomic, economic, and environmental outcomes compared to FP or CT, post-trial surveys and discussions with farmers revealed a strong practical aversion to use of the full suite of CA practices and preference for adapted practices due to logistical constraints in negotiating the hire of laborers for unpuddled manual transplanting.
... While Conservation Agriculture (CA) has been recognized as an excellent method for boosting crop yields sustainably, weed management is often regarded as one of the most difficult aspects [1]. Due to the reduced tillage operation, the composition and dynamics of the weed seed bank in CA will vary as compared to conventional tillage. ...
... Fertilizer N management practices along with increased crop residue retention are getting more attention in Bangladesh in the recent years (Bell et al. 2019). For conservation agriculture, the key is residue retention (Xiao et al. 2021). ...
Article
Ammonia (NH3) fluxes and their soil-related factors were quantified in irrigated maize and potato fields by two split-plot experiments with and without crop residue (CR) together with four fertilizer N rates: N zero (control), farmers’ N (FP), recommended N (RD) and 25% above RD (1.25 RD). CR application together with RD increased NH3 fluxes in maize by 8% in comparison to RD without CR. The NH3 emission factor in maize ranged from 29% in the farmers’ practice (FP-without CR) to 34% in 1.25 RD coupled with CR. Yield-scaled NH3 fluxes increased with N fertilizer application rate. Nitrogen use efficiency (NUE) in maize was 53% higher in FP without CR than in other treatment combinations. In potato, CR coupled with FP reduced NH3 fluxes by 23%. Crop residue and N fertilization rate interaction were significant for NUE, where 1.25 RD without CR increased NUE by 19% when compared with FP-without CR. Stepwise multiple linear regressions showed that mineral N and pH explained 95% of the variances of NH3 fluxes. NH3 fluxes in maize are a significant N loss pathway which is driven mainly by fertilizer N rate, soil mineral N and pH.
... The repeated current practice of growing transplanted rice through puddling and maize with conventional tillage degrades soil structure, delays maize sowing and reduces its yield potential, increases energy and labour requirements, ultimately leading to high production costs. Conservation agriculture (CA)-based tillage and crop establishment options may hold the potential to overcome such problems (Gathala et al., 2013;Alam, 2018;Bell et al., 2019). The development of conservation tillage practices for dry land (drought-prone) crop production has been and will be a dynamic process. ...
Article
Full-text available
The experiment was conducted to study the effect of tillage, mulch and irrigation on soil moisture, yield and yield attributes of hybrid maize (var. BARI Hybrid Maize-6). Two tillage practices (minimum tillage and conventional tillage), two levels of mulches (no mulch and rice straw mulch @ 3 t ha-1) and three irrigation frequencies (one irrigation at 32 days after sowing (DAS), two irrigations at 32 and 55 DAS and three irrigations at 32, 55 and 85 DAS were used as treatment variables. Twelve treatment combinations were assigned in a split-split plot design with three replications. Minimum tillage and mulch conserved more moisture than conventional tillage with no mulch in both years. Minimum tillage and mulch (rice straw) as well as irrigation at 32, 55 and 85 DAS gave higher grain yield than conventional tillage with no mulch and any level of irrigation. Results revealed that application of straw mulch along with three irrigations and any kind of tillage practice might be a suitable combination for obtaining higher yield of maize in drought prone area.
... Variation in physiography, eco-system and environment among regions might be the reasons for using nutrients differently. Rajshahi is situated in the High Barind Tract region and has lower average annual rainfall (1581 mm) than the Mymensingh (2500 mm) and Thakurgoan (2218 mm) districts [50]. Crops grown in Rajshahi district need frequent irrigation water on the predominantly highland and medium highland fields. ...
Article
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Intensive cropping systems with diverse cropping patterns present a challenge for nutrient management on smallholder farms. Government-endorsed recommendations for crop fertilizer use are designed to assist farmers achieve profitable and balanced nutrient inputs, but it is unclear how closely farmers follow these recommendations. We identified farmers' current nutrient use gaps (overuse or underuse) relative to the Government-endorsed recommended nutrient doses in two cropping patterns in three representative Agro-ecological Zones of Bangladesh. A total of 330 farms were surveyed in 2019 from three farm size categories (referred to as large-, medium and small-scale) and their gaps in nutrient use were assessed relative to Government-endorsed Fertilizer Recommendation Guides (FRG) published in 2012 and in 2018: FRG-2012 and FRG-2018. The large-and medium-scale farms used 11-16%, 80-90% and 21-30%, respectively, overdoses of NPK in the cropping season under fully rice-based cropping pattern relative to FRG-2012 recommendations, while the overdose levels were much lower for small-scale farms. Small-scale farms used much less than recommended S, Mg, Zn, B and organic manure (OM) rates relative to FRG-2012. The FRG-2018, which increased N and K recommendations but decreased the P recommendation for rice crops relative to FRG-2012, shows that all farms can decrease the dose of P (by 50%) while small-scale farms need to increase the dose of N (7%), K (16%), S (20%) and to apply Zn in the fully rice-based cropping pattern. On the other hand, the farms could greatly reduce NPK (19%, 86% and 44%, respectively) use while increasing S (14%), Mg, Zn, B and OM use relative to FRG-2018 in the pattern with the high-value potato crop. To increase crop profitability, enhance food security and save Government treasury in the Eastern Gangetic Plain enabling approaches are needed to effectively communicate the benefits of balanced nutrient use practices to farmers.
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No-till mechanized-transplanted rice was evaluated for different combinations of pre- and post-emergence herbicides to determine feasible, economically viable weed management options to control complex weed flora in rice fields. All pre-emergence herbicides significantly reduced the population of grassy weeds; of these, pendimethalin resulted in the greatest reductions (83%) at 15 days after transplanting (DAT). Among five post-emergence herbicide treatments, the combination of bispyribac-sodium (10%SP) + pyrazosulfuron (10%WP) was found to be the most effective in controlling all weed flora at both 35 and 55 DAT. The sequential application of pendimethalin (pre-emergence) followed bispyribac-sodium + pyrazosulfuron (post-emergence) resulted in significantly higher rice grain yield (4.4 t-ha⁻¹) and relative gross-margin (417 USD-ha⁻¹) than all other treatments. A strong negative correlation was observed between rice grain yield and weed biomass, and a strong positive correlation between rice grain yield and weed control efficiency. Our findings demonstrate the potential to combine pre- and post-emergence herbicides in no-till mechanized-transplanted rice; these findings have applications globally in regions where rice is established by no-till or mechanized transplanting.
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Conservation Agriculture (CA) is still a relatively new approach for intensively cultivated (3 crops yr-1) rice-based cropping systems that produce high crop yield and amounts of residues annually. With the recent development of transplanting of rice into tilled strips on non-puddled soil, CA could become feasible for rice-based cropping patterns. However, the effect of increased retention of crop residues on crop response to nitrogen (N) fertilization rate in strip tilled systems with the transplanted rice and other crops grown in the annual rotation is yet to be determined. For nine years, we have examined the effects of soil disturbance levels-strip tillage (ST) and conventional tillage (CT), two residue retention levels-15% residue by height (low residue, LR) and 30% residue (high residue, HR) and five N rates (60%, 80%, 100%, 120%, and 140% of the recommended N fertilizer doses (RFD)) for a rice-wheat-mungbean cropping sequence. The 100% RFD was 75, 100 and 20 kg N ha-1 for rice, wheat, and mungbean, respectively. Rice yields were comparable between the two tillage systems for up to year-6, wheat for up to year-3 but mungbean yield markedly increased in ST from year-1; however, the land equivalent ratio increased from year-1, principally because of higher mungbean yield. Introduction of ST increased land equivalent ratio by 26% relative to CT, N use efficiency and partial factor productivity. Nitrogen fertilizer demand for maximum yield in ST was increased by about 10% for rice and 5% for mungbean but decreased by 5% for wheat. Although fertilizer N demand had increased in ST system due to higher yield than CT, the N requirement declined by50-90% when the same yield goal is considered for ST as for CT. The soil organic carbon stock (0-15 cm) after 8 years increased from 21.5 to 30.5 t ha-1 due to the effect of ST plus high crop residue retention. Annual gross margin increased by 57% in ST over CT practice and 26% in HR over LR retention. In conclusion, after 9 years practicing CA with increased residue retention under strip tillage, the crops had higher N use efficiency, grain yield, land equivalent ratio and annual gross margin in the rice-wheat-mungbean cropping system while the N fertilizer requirement increased minimally.
Article
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Transplanting of rice seedlings in non-puddled soil under conservation agriculture systems is a new promising technology for which effective and economic weed control strategies have to develop. Therefore, a study was conducted in wet season rice during 2013 and 2014 with some commonly used pre- and post-emergence rice herbicides (pyrazosulfuron-ethyl, butachlor, orthosulfamuron, acetochlor + bensulfuron methyl, butachlor + propanil and 2,4-D amine) in strip tilled non-puddled field condition at Mymensingh, Bangladesh to evaluate their weed control efficacy singly or in sequences, their cost-effectiveness and residual effect on the succeeding crops like wheat and lentil. Sole application of herbicide was less effective to control all types of weed species than sequentially applied herbicides. Sequential application of pre- and late post-emergence, early post- and late post-emergence or pre-, early and late post-emergence herbicides controlled weeds by 46-98% and 43-95%, respectively in terms of weed density and biomass. Sequential application of pyrazosulfuron-ethyl followed by orthosulfamuron and butachlor + propanil provided the most effective and economic weed control under this new rice establishment practice. Moreover, the study suggested a range of effective herbicides for strip-tilled non-puddled wet season rice, but possible rotation of those herbicides in a sequential application is needed. Additionally, residue of those herbicides did not show any adverse effect on the succeeding crops of rice like wheat and lentil. However, further research is needed with various new molecules of herbicide and their residual effect on the subsequent crop as well as soil environment.
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Introduction: Soil organic matter (SOM) is central to soil quality and nutrient cycling. In Bangladesh, depletion of soil fertility is a serious threat to sustainability of agricultural production due to high cropping intensity and agriculture practices based on conventional tillage and residue removal (Rijpma and Jahiruddin, 2004). In this situation, CA practices (minimum tillage, crop residue retention and diverse crop rotations) could be a good option for the improvement of soil quality and crop productivity in Bangladesh. However, CA practices are poorly developed for intensive rice-based cropping system and their effect on SOM, plant nutrients and system productivity have not yet been properly addressed. Hence, the present study was undertaken to monitor the changes in SOM and other plant nutrients with system productivity under CA practices in the rice-jute cropping system in the Low Ganges River Floodplain of Bangladesh.
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