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Irrigation and nitrogen effects on tuber yield and water use efficiency of heritage and modern potato cultivars

Authors:
  • Department of Agricultural Research Services, Malawi

Abstract and Figures

There is renewed interest in heritage potatoes in New Zealand, USA and Europe because of their natural flavour and the premiums farmers receive in niche markets. However, a dearth of information on irrigation and nitrogen limit their successful management. This research investigated irrigation and N effects on yield and water use efficiency of heritage and modern potatoes. The 2009/2010 experiment was a split-plot and the 2010/2011 was a Split-Split-Plot with water regimes as the main treatments, four cultivars as sub-treatments and two nitrogen (N) levels, as sub-sub-treatments. The N treatment in 2010/2011 was 20 and 180kgNha-1 of urea at top dressing. Both experiments were basal dressed with 500kgha-1 of 12N:5.2P:14K6:S+2Mg:Ca at planting. The 2009/2010 was top dressed with 100kgNha-1. Data collected was subjected to analysis of variance (ANOVA), using general Linear Model procedure (PROC GLM) in statistical analysis system (SAS). Modern potatoes (Moonlight, Agria) were more responsive to irrigation and N than heritage potatoes (Moe Moe, Tutaekuri). Moe Moe produced as much marketable yield as modern cultivars while Tuteukui had low yields. Application of more than 80kgNha-1 decreased yield in heritage potatoes whereas, it increased the yield of modern potatoes. Full irrigation and 80kgNha-1 improved Moe Moe yields whereas partial irrigation and less than 80kgNha-1 improved Tutaekuri yields. Water use efficiency was high in modern potatoes whereas economic water productivity was high in heritage potatoes. Heritage potatoes tolerated water deficit although they required more water due to late maturity. It was concluded that premium market prices are important to the success of heritage potatoes whereas modern potatoes might use irrigation water more efficiently. It is evident that heritage potatoes can be grown successfully, and that on occasions they use valuable resources efficiently; however a price premium is required to maintain viability.
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Elsevier Editorial System(tm) for Agricultural Water Management
Manuscript Draft
Manuscript Number: AGWAT7407
Title: Irrigation and nitrogen effects on tuber yield and water use efficiency of heritage and modern
potato cultivars
Article Type: SI: WATER IRRI
Keywords: Irrigation, nitrogen, heritage potato, rain-fed, water use efficiency, economic water
productivity, tuber yield
Corresponding Author: Dr. Isaac Rhinnexious Fandika, PhD
Corresponding Author's Institution: Malawi Government
First Author: ISAAC R FANDIKA, PhD
Order of Authors: ISAAC R FANDIKA, PhD; PETER D KEMP, PhD; JAMES P MILLNER, PhD; DAVIE
HORNE, PhD
Abstract: There is renewed interest in heritage potatoes in New Zealand, USA and Europe because of
their natural flavour and the premiums farmers receive in niche markets. However, a dearth of
information on irrigation and nitrogen limit their successful management. This research investigated
irrigation and N effects on yield and water use efficiency of heritage and modern potatoes. The
2009/2010 experiment was a RCBD split-plot and the 2010/2011 was a RIBD Split-Split-Plot with
water regimes as the main treatments, four cultivars as sub-treatments and two N levels, as sub-sub-
treatments. The N treatment in 2010/2011 was 20 and 180 kg N ha-1 of urea at top dressing. Both
experiments were basal dressed with 500 kgha-1 of 12N: 5.2P:14K6:S+2Mg:Ca at planting. The
2009/2010 was top dressed with 100 kgN ha-1. Data collected was subjected to ANOVA, using the
PROC GLM procedure in SAS. Modern potatoes (Moonlight, Agria) were more responsive to irrigation
and N than heritage potatoes (Moe Moe, Tutaekuri). Moe Moe produced as much marketable yield as
modern cultivars while Tuteukui had low yields. Application of more than 80 kg N ha-1 decreased yield
in heritage potatoes whereas, it increased the yield of modern potatoes. Full irrigation and 80 kg N ha-
1 improved Moe Moe yields whereas partial irrigation and less than 80 kg N ha-1 improved Tutaekuri
yields. Water use efficiency was high in modern potatoes whereas economic water productivity was
high in heritage potatoes. Heritage potatoes tolerated water deficit although they required more water
due to late maturity. It was concluded that premium market prices are important to the success of
heritage potatoes whereas modern potatoes might use irrigation water more efficiently. It is evident
that heritage potatoes can be grown successfully, and that on occasions they use valuable resources
efficiently; however a price premium is required to maintain viability.
Suggested Reviewers: Dave Kadyampakeni PhD, MSc, BSC
Scientist, IWMI, IWMI
dakadyampakeni@gmail.com
Profession in Irrigation water Management
Patson Naliva PHD, MSc, BSC/Diploma
Lecturer, Soil Science, LUANAR
patienalivata@yahoo.com
Profession in nutrient management
Shamie Zingore PhD
Scientists, Soil Science, IPNI
s.zingore@inpi.net
Profession in soil and water
Opposed Reviewers: Patson Nalivata PhD
Lecturer, Crop Science, University of Malawi
patienalivata@yahoo.com
Professional in soil and crop production/management.
DAVIe KADYAMPAKENi PhD
Scientist, IWMI, IWMI
dakadyampakeni@gmail.com
Professional
Patson Nalivata PhD
Lecturer, Soil Science, Bunda College of Agriculture
patienalivata@yahoo.com
Professional
Shamie Zingore Zingore PhD
Director, IPNI, IPNI
s.zingore@inpi.net
Soil and Water Scientist
Kasinthula Agricultural Research Station,
P.O Box 28, Chikwawa,
MALAWI
23th April, 2015
Dear Sir/Madam,
SUBMISSION OF MANUSCRIPT
I would like to submit a manuscript entitled “Irrigation and
nitrogen effects on tuber yield and water use efficiency of
heritage and modern potato cultivars” for publication with your
journal.
I am a male Malawian aged 47 and have studied up to PhD degree in
Agriculture obtained from Massey University, New Zealand in November,
2012; MSc in Water Management Advanced Irrigation obtained from
Cranfield University (UK) in 2004 and Bsc/Diploma/Certificate in
Agriculture from University of Malawi/Natural Resources College obtained
in 2002 and 1994, respectively. I have over 12 years experience in
Management and Administration working as Research Station Manager and
20 years experience in Research & Development working as Chief
Agricultural Research Scientist.
Yours faithfully.
Isaac Rhinnexious Fandika, PhD
Cover Letter
Modern potatoes were more responsive to irrigation and N than heritage potatoes.
80kgN ha-1 decrease yield in heritage potato whilst increasing modern potato yield.
Partial irrigation and 80 kg N ha-1 improved yields in heritage potatoes.
Physical WUE is high in modern potatoes but economically high in heritage potatoes.
Heritage potato tolerates water stress and require more water due to late maturity.
*Highlights (for review)
2
Title: Irrigation and nitrogen effects on tuber yield and water use efficiency of heritage and 1
modern potato cultivars 2
Isaac R. Fandika1, 2, Peter D. Kemp1, James P. Millner1, David Horne1 and Nick Roskruge1 3
1Institute of Natural Resources, Massey University, Private Bag 11222, Palmerston North 4410, 4
New Zealand. Email: fandikai@yahoo.co.uk 5
2Kasinthula Agricultural Research Station, Department of Agricultural Research Services, 6
Ministry of Agriculture & Food Security, P.O Box 28, Chikwawa, Malawi. 7
Email: fandikai@yahoo.co.uk; +265 999336212; +265882925512 8
9
Corresponding Author: Isaac R. Fandika1, fandikai@yahoo.co.uk; +265 999336212; 10
+265882925512 11
12
Abstract 13
There is renewed interest in heritage potatoes in New Zealand, USA and Europe because of 14
their natural flavour and the premiums farmers receive in niche markets. However, a dearth 15
of information on irrigation and nitrogen limit their successful management. This research 16
investigated irrigation and N effects on yield and water use efficiency of heritage and modern 17
potatoes. The 2009/2010 experiment was a RCBD split-plot and the 2010/2011 was a RIBD 18
Split-Split-Plot with water regimes as the main treatments, four cultivars as sub-treatments 19
and two N levels, as sub-sub-treatments. The N treatment in 2010/2011 was 20 and 180 kg N 20
ha-1 of urea at top dressing. Both experiments were basal dressed with 500 kgha-1 of 12N: 21
5.2P:14K6:S+2Mg:Ca at planting. The 2009/2010 was top dressed with 100 kgN ha-1. Data 22
collected was subjected to ANOVA, using the PROC GLM procedure in SAS. Modern 23
*Manuscript
Click here to download Manuscript: Fandika - 2015.docx Click here to view linked References
3
potatoes (Moonlight, Agria) were more responsive to irrigation and N than heritage potatoes 24
(Moe Moe, Tutaekuri). Moe Moe produced as much marketable yield as modern cultivars 25
while Tuteukui had low yields. Application of more than 80 kg N ha-1 decreased yield in 26
heritage potatoes whereas, it increased the yield of modern potatoes. Full irrigation and 80 27
kg N ha-1 improved Moe Moe yields whereas partial irrigation and less than 80 kg N ha-1 28
improved Tutaekuri yields. Water use efficiency was high in modern potatoes whereas 29
economic water productivity was high in heritage potatoes. Heritage potatoes tolerated water 30
deficit although they required more water due to late maturity. It was concluded that 31
premium market prices are important to the success of heritage potatoes whereas modern 32
potatoes might use irrigation water more efficiently. It is evident that heritage potatoes can 33
be grown successfully, and that on occasions they use valuable resources efficiently; however 34
a price premium is required to maintain viability. 35
36
Keywords: Irrigation, nitrogen, heritage potato, rain-fed, water use efficiency, economic 37
water productivity, tuber yield 38
Introduction 39
Heritage potatoes (Solanum tuberosum) refer to speciality potato cultivars or very old 40
Southern America native potato cultivars that Europeans originally transported or smuggled 41
to Europe and other parts of the world, traditionally produced without a patent (Voss et al., 42
1999). Generally, heritage potatoes are cultivated by small farmers and have a diversity of 43
yield potential, tuber size and multi-colour skin/flesh (yellow-flesh, purple skin, red flesh) 44
(Harris 2001; Voss et al., 1999). Consumer demand for such multi-coloured potatoes is high 45
in the USA, South America (Voss et al., 1999), New Zealand (Hayward, 2002; McFarlane, 46
2007) and Europe niche markets, due to their natural flavour (Walker, 1996), texture or 47
4
colour and health benefits (Singh et al., 2008; Lister 2001). They also have good nutritional 48
traits and ‘novel’ value. Premium prices are offered for heritage potatoes in New Zealand 49
(Hayward, 2002; McFarlane 2007) and USA (Voss et al., 1999) because of novelty value as 50
well as for their cultural value (Lambert, 2008; McFarlane, 2007). Consequently, there is an 51
interest in producing heritage potatoes to supply those niche markets. 52
California is the largest producer and market for speciality potatoes in USA (Voss et al., 53
1999). In New Zealand, the indigenous Polynesian population (Maori) traditionally produce 54
these potatoes, collectively known as Taewa (Roskruge, 1999). Heritage potatoes have other 55
increased advantages including biodiversity and most of them are self selected, hence have 56
potential to withstand biotic and abiotic stresses (Roskruge, 2010). However, speciality or 57
heritage potatoes growers in USA (Voss et al., 1999), Europe and New Zealand experience 58
low yields (Harris 2001; Harris et al., 1999). Heritage potatoes generally respond less to 59
inputs such as irrigation and N input compared with modern cultivars (Fandika et al., 2010; 60
Hayward, 2002). Most heritage cultivars are produced without appropriate water and soil 61
management as also observed in burley (Abeledo et al., 2011). Growers of heritage cultivars 62
need to be able to use water and N resources prudently by selecting suitable cultivars, in order 63
to maximise yields and returns. This research compares tuber yield, water and nitrogen use 64
efficiency of heritage and modern potato cultivars in response to irrigation and nitrogen 65
fertiliser management. 66
Materials and Methods 67
Location and experimental design 68
Two heritage potatoes, Moe Moe (S. tuberosum L.) and Tutaekuri (Solanum andigena Juz. & 69
Buk.) and two modern cultivars, Moonlight and Agria (S. tuberosum L.) were compared in the 70
field at the Pasture and Crop Research Unit, Massey University, Palmerston North from 10th 71
5
November, 2009 to May, 2010 and from 27th October, 2010 to April, 2011. The site is located 72
at a latitude of 40o 22. 54.02 S, longitude 175 o 36’ 22.80 E, and an altitude of 36 m above 73
sea-level. The soil type is Manawatu sandy loam, a recent alluvial soil. The soil samples were 74
analysed at Massey University’s Fertilizer and Lime Research Centre. The soil properties 75
were: pH 5.4, Olsen P 36 mg kg-1 and K 86.02 mg kg-1. The soil bulk density was 1.35 g cm-3 76
and the volumetric soil water content, at field capacity and wilting point, were 0.35 and 0.17 m3 77
m-3, respectively. There were 106 kg ha-1 of available N and 76.8 mg N kg-1 of soil 78
anaerobically mineralised N at the beginning of the 2009 - 2010 experiment. In 2010 - 2011, 79
total available N was <30 kg N ha-1. Figure 1 presents the maximum and minimum 80
temperature, evapotranspiration and rainfall (mm) for the site during the experiment. 81
82
The 2009-2010 experiment was a randomised complete block split-plot design, with rain-fed 83
and full irrigation (as the main treatments) with four potato cultivars as sub-treatments. This 84
crop received 12N:5.2P:14K:6S+2Mg+5Ca, using 500 kg Nitrophoska Blue TE at planting 85
on 10th November, 2009 and this was followed by 100 kg N ha-1 of urea, as a side dressing, 86
on 15thDecember, 2009. Potato tubers were manually sown at 75 cm spacing between rows 87
and 40 cm spacing within rows at a depth of 10 - 15 cm. Each plot was 6 m by 1.5 m and 88
each plot held 30 plants. Each plot had two guard rows planted with the Desiree variety. The 89
2010/2011 experiment was a Randomised Incomplete Block Split-Split-Plot Design with 90
rain-fed (Pe); (2) partial irrigation (PI) and (3) full irrigation (FI) (as the main treatments): 91
three potato cultivars (Agria, Moe Moe and Tutaekuri) as sub-treatments and two N levels 92
(N1=80; N2=240 kg N ha-1), as sub-sub-treatments. Both experiments were replicated four 93
times. All plots received the same amount of fertiliser as in 2009/2010 at planting but N1 and 94
N2 treatments were side dressed by 20 and 180 kg N ha-1 on 10th December, 2010. Spacing 95
within plants was 30 cm and other parameters were as 2009/2010 above. 96
6
Irrigation scheduling and soil moisture measurements 97
Irrigation was applied with a Trail T150-2 traveller irrigator. A soil water balance was used to 98
determine the soil moisture deficit (SMD) on a daily basis during the growth of the crops 99
(Premrov et al., 2010). The potential evapotranspiration in the soil water balance was 100
computed using the FAO 56 Penman-Monteith method (Allen et al., 1998; Kassam et al., 101
2001). The daily weather data, for running the soil water balance model, were collected 102
weekly from NIWA/AgResearch climate site, Palmerston North. The soil water balance was 103
used to schedule irrigation events and to calculate the quantity of drainage (Dp) over the 104
growing period. The full irrigation treatment was based on refilling 25 mm of the soil’s 105
moisture deficit (SMD) on the day that soil moisture deficit equated to or exceeded 30 mm. 106
This schedule was based on supplying approximately half the ‘readily available water’ held 107
by the soil at the site. Partial irrigation treatment did not receive irrigation at the first 108
irrigation of the full irrigation treatment and was then irrigated at every second full irrigation. 109
The actual water distribution within each plot was monitored (at every irrigation) by using a 110
number of catch cans. The catch cans were laid longitudinally at 0.5 m apart. At the end of 111
the irrigation period, water trapped in the cans was measured and recorded. The irrigation 112
depth for a particular plot was determined as an average of the water depth in the six catch 113
cans from each plot. 114
115
The actual crop evapotranspiration (ETc) was determined using equation 1 (Allen et al., 116
1998). Soil moisture change (∆S) was the difference between soil moisture content at the end 117
and the start of the field experiment as measured using a Time-Domain Reflectometer, 118
model 1502C, Tektronix Inc., Beaverton, OR, USA. In addition to measuring soil water 119
content at the start and conclusion of the trial, it was also monitored before irrigation and 24 120
7
hours after irrigation to a depth of 50 cm. As the site was flat and the crops were in the 121
ground for the summer/autumn period, surface runoff can be ignored. 122
123
ETc = P + I - Dp - Ro+ ∆S Equation 1 124
125
Tuber yield components, Nitrogen use efficiency and water use efficiency 126
After physiological maturity, the crop was harvested using a potato harvester. Total tuber 127
yield (kg); marketable tuber yield; number of tubers per plant; average tuber weight, 128
aboveground (leaves+stems) and total biomass (leaves+stems+tuber) were measured. The 129
harvest index (HI) was calculated as the ratio of total tuber yield to total biomass production 130
on dry weight basis, in five samples from each plot (Mackerron & Heilbronn, 1985). Tubers 131
were later graded into marketable and non-marketable grades (NM): a marketable tuber was 132
above 55g without any defects and a non-marketable tuber was <55g and those with defects. 133
Water use efficiency (WUE) was defined as fresh matter production per unit water applied as 134
rainfall, plus irrigation, plus change in soil moisture content (Howell, 2001). Nitrogen use 135
efficiency (NUE) was determined as the total tuber yield, per unit of N applied per treatment 136
(kg N kg-1) (Darwish et al., 2006; Zebarth et al., 2008). 137
Statistical Analysis 138
Tuber yield and components data was analysed with the General Linear Model (GLM) 139
procedure of the Statistical Analysis System (SAS, 2008). Differences amongst treatment 140
means were compared by the Least Significant Difference test (LSD), at 5% probability 141
(Meier, 2006). A simple correlation analysis was used to assess the relationship between the 142
daily crop water use and solar radiation, maximum temperatures and wind from November to 143
April. A simple correlation was also used to assess the relationship between number of tubers 144
per plant to the average tuber weight and HI. 145
8
Results 146
147
Crop water use and volumetric soil moisture content 148
Heritage potato cultivars matured 179 and 170 days after planting whereas modern potatoes 149
took 132 and 140 days to mature in 2009/2010 and 2010/2011, respectively. Heritage 150
potatoes potentially required 610 mm and 611 mm whilst modern potatoes required 550 and 151
491 mm in the respective years (Figure 1). Precipitation supplied 60 - 69% of the water 152
requirement. Consumptive water use (m3 ha-1) was highest in the FI and lowest in the Pe 153
treatment, whilst PI was intermediate. Heritage potatoes used more water compared to the 154
modern cultivars in both experiments. Since precipitation was not well distributed during the 155
growing seasons, irrigation reduced the soil moisture deficit in all cultivars. 156
157
Volumetric soil moisture content (%) in the Pe treatments ranged between 15 - 20%, whilst 158
irrigated treatments ranged between 20 - 35% (Figure 2). Full irrigation increased soil 159
moisture content, whereas N had no effect on soil moisture content in 2010 - 2011 (P>0.05). 160
The daily crop water use (in both years) was strongly influenced by solar radiation (P<0.0001) 161
and maximum temperatures (P<0.0001), but was not influenced by. The high temperature and 162
solar radiation experienced in January and February caused the maximum ETc. 163
164
9
Tuber yield and components 165
Irrigation significantly increased average tuber weight (P<0.001), total tuber yield (P<0.0001) 166
and marketable tuber yield in 2009 - 2010 (P<0.01; Table 1). The average number of tubers 167
per plant and HI were not influenced by irrigation. However, cultivar strongly influenced the 168
number of tubers per plant, average tuber weight (P<0.0001), total and marketable tuber yield 169
(P<0.0001) and HI (P<0.0001) in 2009 - 2010 (Table1). In 2010 - 2011, tuber yield and all 170
yield components above were influenced by cultivar (P<0.0001), irrigation (P<0.001) and N 171
(P<0.0001; Table 1). 172
173
Modern cultivars had the lowest number of tubers per plant, Tutaekuri the highest whilst Moe 174
Moe was intermediate. The greatest average tuber weight was found in Agria, the least in 175
Tutaekuri. Modern cultivars had higher HI, total and marketable tuber yield than heritage 176
potatoes, except in 2009/2010 when Moe Moe produced as much yield as modern cultivars. 177
Moe Moe and Agria had more tubers under rain-fed conditions in 2009/2010. Modern 178
cultivars did not differ in the number of tubers per plant and average tuber weight traits, 179
whilst heritage potatoes differed from each other (P<0.0001; Table 1). The behaviour of 180
translocating assimilates to the harvested product was clearly demonstrated by the high HI in 181
Agria. Tutaekuri had the lowest HI whilst Moe Moe was intermediate. The number of tubers 182
and the average tuber weight were negatively related to average tuber weight (Average tuber 183
weight (g) = - 1.6618 (Tubers plant-1) + 110.29, R2 = 66.3%) and HI (HI = - 0.0059 (Tubers 184
plant-1) + 0.8902, R2 = 60.5%) in 2009/2010. The increase in the number of tubers per plant 185
in heritage potatoes significantly decreased the average tuber weight and HI. 186
187
In 2009/2010, irrigation did not affect the number of tubers per plant in modern cultivars, or 188
the number of tubers, the mean tuber weight and total and marketable tuber yields in 189
10
Tutaekuri (P>0.05). Conversely, the number of tubers per plant in Moe Moe were reduced 190
and there was an increase in the mean tuber weight with irrigation (P<0.001). Subsequently, 191
the total and marketable tuber yields in Agria, Moonlight and Moe Moe did not differ but 192
they were all higher yielding than Tutaekuri, under both irrigation treatments in 2009/2010 193
(P<0.0001). Full irrigation reduced yields in Tutaekuri and PI enhanced yields more than FI 194
and rain-fed treatment in 2010/2011 (Figure 6). Partial irrigation increased tube yield by 195
increasing number of tubers and FI by enhancing mean tuber weight. Nitrogen did not 196
increase the average tuber yield (P<0.05). 197
198
Irrigation enhanced the average tuber weight, fresh total tuber yield and marketable tuber 199
yield, by 51%, 33% and 55% in 2009/2010, respectively. In 2010/2011, FI increased the 200
number of tubers per plant; mean tuber weight; total tuber yield; and marketable tuber yield 201
by 18%, 6%, 43% and 49%, whilst PI enhanced them by 24%, 6%, 26% and 13%, 202
respectively (Table 1). However, high N decreased tuber numbers; total tuber yield and 203
marketable tuber yield by 16%, 17% and 14%, respectively (P<0.0001). On the other hand, N 204
did not enhance average tuber weight (P>0.05). 205
206
There was irrigation and cultivar interaction on tuber yield in 2009/2010 resulting from 207
increased tuber yields in Agria, Moonlight and Moe Moe, but not in Tutaekuri with FI 208
(P<0.01; Figure 3). The effect of water stress was highly pronounced in Agria and Moonlight 209
compared with the heritage cultivars. In 2010 - 2011, significant interactions were observed 210
between cultivars and irrigation on the number of tubers per plant (P<0.0001, Figure 4a) and 211
total and marketable tuber yield (P<0.0001, Figure 6). Cultivar and N significantly interacted 212
on the number of tubers per plant (P<0.01, Figure 4b) and mean tuber weight (P<0.05, Figure 213
5), total and marketable tuber yield (P<0.0001). Significant interactions were also observed 214
11
between cultivar, irrigation and N on total and marketable tuber yield (P<0.01) (Figure 7). No 215
interactions were observed between irrigation and N (P>0.05), apart from HI (P<0.05). 216
217
The interaction involving the tuber numbers per plant was a consequence of decreased tuber 218
with FI and rain-fed, whilst it increased with PI in Tutaekuri. In other cultivars, the number of 219
tubers decreased from FI to rain-fed (Figure 4a). Nitrogen reduced tuber number per plant in 220
heritage cultivars but not in Agria (Figure 4b). The mean tuber weight in Agria increased 221
with N increase, whereas heritage potatoes decreased its mean tuber weight with N increase 222
(Figure 5). Similarly, total and marketable tuber yield in Agria increased with high N but 223
decreased in heritage cultivars (Figure 6). Without irrigation, the response to N was reduced 224
(Figure 7). Tutaekuri performed better under PI compared to FI and rain-fed, whilst the 225
remaining cultivars performed best under FI (Figure 6a). 226
227
Water use efficiency and nitrogen use efficiency 228
Water use efficiency mirrored tuber yield in both years, whereas economic water productivity 229
(EWP in NZ$/m3) reflected the product marketable value, in addition to tuber yield (Table 1 230
& 2). Water use efficiency was highest in Moonlight in 2009/2010 (Table 1) and in Agria in 231
2010/2011 and lowest in Tutaekuri, whereas Moe Moe was intermediate in both years 232
(P<0.0001). Water use efficiency was significantly influenced by water regimes (P<0.001) 233
and N (P<0.0001) in all cultivars, although differently. In 2009/2010, rain-fed treatments had 234
high WUE. Tutaekuri had significicantly lower WUE (P<0.05) than all other cultivars apart 235
from Agria whereas WUE in Moonlight did not differ from Moe Moe under rain-fed 236
conditions. Under irrigated conditions, WUE was higher in Moonlight (Table 1). 237
238
12
In 2010/2011, WUE was highest under PI and low N, whereas FI had the lowest WUE (Table 239
1). Rain-fed treatment was intermediate but not different from either PI or FI. Full irrigation 240
decreased WUE, whilst PI increased it in all cultivars (Figure 8). Water use efficiency 241
decreased with increasing N in Taewa and rain-fed Agria, whereas PI and FI did not affect 242
WUE at high N in Agria (P<0.01, Fig. 8). Economic water productivity was highest in Moe 243
Moe and lowest in Tutaekuri, with Agria intermediate (P<0.0001, Table 2). Partial irrigation 244
and low N increased EWP, whilst FI and high N decreased EWP (P<0.01, P<0.0001). The 245
interaction involving EWP resulted from the increase in EWP at high N and PI in Agria, 246
whereas Taewa had decreased EWP at high N. 247
248
Nitrogen use efficiency was highest in Agria, (P<0.0001), FI (P<0.0001) and low N 249
treatments (P<0.0001; Table 2; Figure 9). Tutaekuri, rain-fed and high N treatments had the 250
lowest NUE. Interaction effects were observed between water regime and cultivars 251
(P<0.0001); water regime and N (P<0.01); cultivars and N (P<0.0001); cultivar and water 252
regime and N on NUE in 2010/2011 (P<0.05). Full irrigation increased NUE in Agria and 253
Moe Moe, whereas PI increased NUE in Tutaekuri. High N decreased NUE by over 300% in 254
heritage cultivars, whereas rain-fed decreased it by 40% (Table 2). Partial irrigation had an 255
intermediate influence on NUE in Moe Moe and Agria (Figure 9). 256
257
Discussion 258
Crop water use and tuber yield 259
The study indicates that irrigation improves potato tuber yields (Erdem et al., 2006) and also 260
that there are potato genotypic differences in water use (Steyn et al., 1998; Trebejo et al., 261
1990; Wolfe et al., 1983). The heritage and modern potatoes differed in their maturity and 262
13
water requirement. The heritage potatoes used more water than modern cultivars when water 263
was available because they mature later. However, heritage potatoes were more adapted to 264
water deficit compared to modern potatoes. The rainfall did not supply enough water to both 265
heritage and modern potatoes to meet their water requirements. Consequently, rain-fed 266
conditions resulted in a greater reduction in tuber yield than partially irrigated potatoes. 267
Growers need to understand the growing stages and related daily water use of their heritage 268
potatoes in order to improve yield and WUE. 269
270
Tuber yield increased linearly with irrigation, depending on genotypes, with the highest 271
increase being found in modern potatoes. Conspicuously, the response to irrigation was high 272
in cultivars that are very sensitive or not tolerant to water stress, predominantly modern 273
cultivars. This is interestingly supported by the high reduction of modern potatoes yields 274
with a mild water stress, as compared to the heritage cultivars. This supports Trebejo, (1990) 275
findings that cultivars which perform well under adequate water may not do well under water 276
stress, unless the cultivar is stable to both a stressed and non-stressed environment, as 277
observed with Moe Moe in 2009 - 2010. 278
279
The yield response to irrigation and N of heritage potatoes was generally lower than the 280
modern potato cultivar. For instance, Moe Moe and Agria tuber yield responded to FI, whilst 281
Tutaekuri responded to PI. Both Tutaekuri and Moe Moe decreased tuber yield with high N, 282
whereas Agria increased tuber yield with high N. The high N reduced tubers per plant, tuber 283
weight and HI in heritage potatoes, whilst increasing them in the modern cultivar. This 284
indicates that, although N improves yields in irrigated potato more than in water-stressed 285
fields (Ferreira et al., 2007), the response to N depends on cultivars, as reported for Agria, 286
Fianna, Russet Burbank, Ilam Hardy and Kennebec cultivars in New Zealand (Craighead et 287
14
al., 2003). Consequently, heritage potatoes growers do not need to apply up to 210 - 250 kg 288
ha-1 of N applied to modern potato cultivars (Craighead et al., 2003). 289
290
Irrigation enhances potato yields through the modification of mean tuber weight and number 291
of tubers per plant differently, depending on the cultivar (Belanger, 2002; Walworth et al., 292
2002). In both years, FI moderately improved the number of tubers, HI and mean tuber 293
weight in Agria and Moe Moe, whilst decreasing them in Tutaekuri. However, the adjustment 294
in Moe Moe in 2009 - 2010 was accompanied by a modification of the number of tubers per 295
plant be fewer than under rain-fed. The increase in mean tuber weight confirms other findings 296
by Bélanger et al.(2002), Ferreira et..al. (2007) and Yuan et al. (2003), while the decrease in 297
number of tubers with irrigation in Moe Moe is contrary to Belanger et..al. (2002) and Yuan 298
et..al. (2003), who reported an increase of tuber numbers per plant with irrigation as also 299
observed in 2010 - 2011. 300
301
In 2009 2010, Moe Moe (a heritage cultivar) had competitively produced equally to modern 302
cultivars, due to an intermediate number of tubers and mean tuber weight. Moe Moe yield 303
was more than the average potato yield of 45.3 - 50.2 t ha-1 in New Zealand (FAO, 2009; 304
McKenzie, 1999). It was also above world potato average yields, which range from 10.8 to 305
41.2 t ha-1 (FAO, 2009a). This result is also within the average potato tuber yield range of 38 306
- 55.4 t ha-1, upon which most modern potatoes are accepted for release (Anderson et al., 307
2004; Genet et al., 1997; Genet et al., 2001). The performance of Moe Moe dispeled claims 308
which generalise that heritage potatoes are 50% poorer in their yields (Harris et al., 1999) and 309
it indicated the possibility of achieving high yields in heritage potatoes heritage potatoes with 310
correct water management. 311
312
15
Full irrigation and high N terrifically failed to improve the tuber yield in one heritage cultivar, 313
Tutaekuri, possibly due to differences in their sub-species and HI. Tutaekuri is sub-specie 314
andigena, whilst others are sub-specie tuberosum. Tutaekuri behaviour in response to 315
irrigation and N confirms that modern cultivars are bred for high N responsiveness while old 316
or wild cultivars have low N use because they were self-selected for adverse condition 317
(Zebarth et al., 2008; Siddique et al., 1990a). However, S. andigena, (Tutaekuri) yield 318
potential appears to be lower than the average of S. tuberosum (Moe Moe) yields. Kumar et 319
al. (2006) described S.andigena yields to be primitive and limited by large above-ground 320
biomass, large tuber numbers per plant and small tuber size. The tuber yield gap between the 321
two heritage potatoes is very wide and difficult to close through agronomic practices because 322
it is dependent on genotypic variation. Nevertheless, the study indicates the possibility of 323
achieving higher tuber yields in S.andigena (Tutaekuri), with partial irrigation and low N. 324
The tuber yields for both heritage potatoes varied with season and N levels. The main driver 325
of change in the average tuber yields between the seasons was the potato psyllid infestation in 326
2010 - 2011. Compared with 2009 - 2010, heritage potatoes production in 2010 - 2011 327
decreased, with an average tuber yield of 18.1 t ha-1 in Moe Moe and 10.9 t ha-1 in Tutaekuri. 328
This result shows that one of the main limitations to heritage potatoes is potato psyllid 329
infestation, apart from low yield potential, inappropriate N and water management. Pest 330
control is essential in heritage potatoes, despite their hardiness and tolerance to some biotic 331
and abiotic stresses, which have been developed through their self-selection (Roskruge et al., 332
2010). Therefore, heritage potato growers are advised to strategise pest and disease 333
management, in order to attain maximum yields and to avoid tuber yield decrease between 334
seasons. 335
336
16
Visual surveillance showed potato psyllid symptoms 110 - 150 days after planting (Table 2; 337
Fig. 10). The attack had less impact on Agria yield, since it had already developed tubers, 338
whilst heritage potatoes were still developing tubers when infested: hence, heritage potatoes 339
yields were probably decreased due to the pest’s disruption of the photosynthesis and tuber 340
dry matter accumulation process. This study is illustrative of the claim that the low tuber 341
yields commonly reported for heritage potatoes may be at least partly due to pests, low HI 342
and inefficient water management. However, these tuber yields are considerably above the 343
current mean total and marketable tuber yields attained by heritage potato growers, ranging 344
from 15 - 20 t ha-1 and 10 - 15 t ha-1, respectively (Roskruge, 2011 pers. comm.). Appropriate 345
irrigation and N application contributes to improvement in the tuber yield of heritage potatoes. 346
Full irrigation and PI combined with less than 80kg N ha-1, respectively, raised Moe Moe and 347
Tutaekuri tuber yields towards a potential yield of 40 t ha-1. 348
349
Water use efficiency and Nitrogen use efficiency 350
Amongst the world’s major food crops, potato has been reported to have a high WUE of 6.2 - 351
11.6 kg m-3, compared to cereal and legume grain crops (Bowen, 2003; FAO, 2008; 352
Thompson et al., 2003; Zhang et al., 2005). The WUE for modern potato and Moe Moe are 353
within this range. The WUE for potato has been reported above 11.6 kg m-3, as also observed 354
with some modern potato in this study (Kang et al., 2004; Trebejo et al., 1990). Erdem et al. 355
(2006) reported WUE for potatoes below 6.2 kg m-3, as observed in Tutaekuri. The reason for 356
low WUE in Tutaekuri could be its genetics on small tuber size or higher tuber number and 357
higher vegetative growth than tuber yield. The WUE for Tutaekuri would improve with the 358
enhancement of HI as reported in grain WUE (Siddique et al., 1990). Nevertheless, the WUE 359
for Tutaekuri is above WUE for the major crops of the world and therefore, may be a 360
valuable crop when water is limited. 361
17
362
Modern potatoes have high physical WUE, but they are not as economically productive under 363
the same volume of water as heritage potatoes. Similarly, the irrigation scheduling 364
technology, for improving WUE in Agria, is different for Tutaekuri. The results on EWP 365
confirm the findings of Nielsen et al. (2005) that WUE, based on a dollar return per unit of 366
water used, is sometimes high in those crops found with low evaporative demand, rather than 367
those crops with a high evaporative demand (Nielsen et al., 2005; Nielsen et al., 2006 ). 368
Likewise, market values or high values have determinature effect on water productivity. 369
Aldaya et al. (2008) reported that the use of water for low value crops is sometimes the main 370
problem, rather than water scarcity. Vegetables with high value were more economically 371
productive, per volume of water (15 Euro/m3 ≈ 27 NZ$/m3), than grain cereal with less value 372
(0.3 Euro/m3 in Spain (Aldaya et al., 2008). In this study, heritage potatoes demonstrated 373
higher cash per volume of water used than modern potatoes with their high yield per unit of 374
water. These results, together with those reported from other authors; suggest that the market 375
value of a product should be one of the driving forces in the allocation of water in agriculture. 376
Nitrogen use efficiency was found to be highest under unlimited irrigation and limited N, but 377
the consequence is that WUE is reduced. On the other hand, NUE was found to greatly differ 378
between modern potato and Taewa. This finding is similar to Zebarth et al. (2008) who found 379
that commercial potato cultivars have a higher or equal NUE, compared to Andean primitive 380
cultivars. However, this study does not agree with Zerbarth’s earlier study (Zebarth et al., 381
2004), which indicated that late maturity increases NUE: heritage potatoes, although late 382
maturing, had a low NUE compared to the short duration cultivar, Agria. 383
In another similar study, Errebhi et al. (1999) assessed NUE in tuber bearing solanum species 384
(wild Species and their hybrids) and commercial cultivars, at low and high N. It was found 385
that NUE was highest in wild species, with a minimal difference from Russet Burbank, but it 386
18
was greater than that found in other modern potato cultivars (Errebhi et al., 1999). Heritage 387
potatoes, especially Tutaekuri, has low NUE and WUE, due to their self-selection for survival 388
to adverse competition and environmental factors, whilst modern or commercial potato 389
cultivars are either bred for high NUE or WUE (Zebarth et al., 2008). However, the 390
comparison of heritage potatoes NUE with wild species (Errebhi et al., 1999) suggest that 391
NUE also varies between unimproved potato species (heritage or wild specises) with others 392
exhibiting high NUE whilst others low NUE. Partial irrigation and low N are significant 393
resource saving strategies for heritage potatoes, through the lowering of actual ET below full 394
water supply, whilst keeping tuber yield that approached the tuber yield of modern potatoes. 395
Therefore, the use of high WUE potato cultivars, moderate N and appropriate irrigation 396
scheduling, facilitates the maximisation of crop water productivity (Wallace, 2000; Morison et 397
al., 2007). 398
Conclusion 399
400
Modern potatoes are more responsive to irrigation and N application than heritage potatoes. 401
Some heritage potatoes can produce as much marketable yield as modern cultivars while 402
other heritage potatoes have lower yields than modern heritage. The heritage potatoes use 403
more water (when available), due to late maturity, and are also tolerant to water and N deficit 404
in time of scarcity, unlike modern potatoes. As a result, irrigation and N are important for 405
both heritage and the modern potatoes although in different ways. The higher number of 406
tubers and the disparity in water and N agronomic practices contribute to the low yield and 407
WUE commonly observed in heritage potatoes. Full irrigation and high N are recommended 408
for modern potatoes; FI and 80 kg N ha-1 are recommended for Moe Moe whereas PI and less 409
than 80 kg N ha-1 are recommended for Tutaekuri production. 410
19
Modern cultivars have higher WUE and NUE than some heritage potatoes. Moe Moe, a 411
heritage cultivar has comparable yield and physical WUE capability to modern cultivars. The 412
heritage cultivars’ WUE is high when assessed in economic terms. The low HI, the higher 413
number of tubers and the disparity in appropriate agronomic practices (pest control) 414
contribute to the low yield and physical WUE commonly observed in heritage crops. In this 415
case, it can be concluded that most heritage crops have a potential for maximising yield with 416
proper irrigation and N strategies. It is evident that heritage crops can be grown successfully, 417
and that on occasions they use valuable resources efficiently. To enhance water use efficiency, 418
management of heritage heritage potatoes should focus on improving the harvest index. 419
Acknowledgement 420
We are indebted to New Zealand’s International Aid and Development agency and the 421
Malawi Government for providing Mr Fandika with a Commonwealth Scholarship, in order 422
to pursue PhD programme. We are also grateful to the Institute of Natural Resources, Massey 423
University, New Zealand for partly funding this research. Lastly, we would like to thank all 424
the technical support from Mark Osborne and Esther Fandika for providing support with 425
other field work during this study. 426
REFERENCES 427
Allen, R.G., Pereira, L.S., Raes, D., & Smith, M. (1998). Crop evapotranspiration. Guidelines 428
for computing crop water requirements. FAO Irrigation and Drainage Paper 56. Rome, 429
Italy: Food and Agriculture Organization of the United Nations (FAO). 430
Anderson, J.A.D., & Lewthwaite, S.L. (2004). Moonlight : A new dual-purpose main crop 431
potato (Solanum tuberosum) cultivar. New Zealand Journal of Crop and Horticultural 432
Science, 32:153-156. 433
Bélanger, G., Walsh, J., Richards, J., Milburn, P., & Ziadi, N. (2002). Nitrogen fertilization 434
and irrigation affects tuber characteristics of two potato cultivars. American Journal 435
of Potato Research, 79(4):269-279. 436
Bowen, W.T. (2003). Water productivity and potato cultivation. Pp. 239-238. In: Water 437
productivity in agriculture: limits and opportunities for improvement Eds Kijne, J.W., 438
Barker R. and Molden, D. CABI Publishing, Wallingford, UK. 439
Craighead, M.D & Martin, R.J. (2003). Fertiliser responses in potatoes An overview of past 440
Ravensdown research. Agronomy New Zealand, 32:15 - 25. 441
20
Darwish, T.M., Atallah, T.W., Hajhasan, S., & Haidar, A. (2006). Nitrogen and water use 442
efficiency of fertigated processing potato. Agricultural Water Management, 85(1-443
2):95-104. 444
Erdem, T., Erdem, Y., Orta, H., & Okursoy, H. (2006). Water-yield relationships of potato 445
under different irrigation methods and regimens. Scientia Agricola, 63: 226-231. 446
Errebhi, M., Rosen, C., Lauer, F., Martin, M., & Bamberg, J. (1999). Evaluation of tuber-447
bearing Solanum species for nitrogen use efficiency and biomass partitioning. 448
American Journal of Potato Research, 76(3):143-151. 449
FAO (2003). Unlocking the water potential of agriculture. Rome, Italy: Food and Agriculture 450
Organization of the United Nations (FAO). 451
FAO (2008). Potato and water resources. Rome, Italy: Food and Agriculture Organization of 452
the United Nations, Viale delle Terme di Caracalla. 453
FAO (2009). New light on a hidden treasure : International year of the potato 2008. Rome, 454
Italy: Food and Agriculture Organization of the United Nations, Viale delle Terme di 455
Caracalla. www.fao.org/agriculture/crops/core-themes/theme/...potato/en/Cached 456
Ferreira, T.C., & Gonçalves, D.A. (2007). Crop-yield/water-use production functions of 457
potatoes (Solanum tuberosum, L.) grown under differential nitrogen and irrigation 458
treatments in a hot, dry climate. Agricultural Water Management, 90(1-2):45-55. 459
Genet, R.A., & Braam, W.F. (1997). White Delight: A new maincrop fresh market potato 460
cultivars. New Zealand Journal of Crop and Horticultural Science, 25: 93-95. 461
Genet, R.A., Braam, W.F., Gallagher, D.T.P., Anderson, J.A.D., & Lewthwaite, S.L. (2001). 462
Dawn - A new early-maincrop fresh market/crisping potato cultivar. New Zealand 463
Journal of Crop and Horticultural Science, 29:67-69. 464
Harris, G.F., & Niha, P.P. (1999). Maori potato. Working Paper. The Open Polytechnic of 465
New Zealand. 466
Harris, G.F. (2001). Nga Riwai Maori- Maori potatoes. A thesis presented in partial 467
fulfilment of the requirements for the degree of Master of Philosophy in Ethnobotany 468
at Massey University, Palmerston North, New Zealand. 469
Hayward, S. (2002). The effect of nitrogen and plant density on the growth and development 470
of taewa. A research project presented in partial fulfulfilment of the requirements of 471
the postgraduate Diploma in Maori Resource Development. Postgraduate Diploma in 472
Maori Resource Development, Massey University, Palmerston north, New Zealand. 473
Hoekstra, A., & Chapagain, A. (2007). Water footprints of nations: Water use by people as a 474
function of their consumption pattern. Water Resources Management 21, 35-48. 475
Kang, Y., Wang F-Xin, Liu, H.-J., & Bao-Zhong. (2004). Potato evapotranspiration and yield 476
under different drip irrigation regimes. Irrigation Science, 23(3):133-143. 477
Kassam, A., & Smith, M. (2001). FAO methodologies on crop water use and crop water 478
productivity. Rome, Italy: Food and Agriculture Oorganisation of the United Nations 479
(FAO). 480
Kumar, R., & Kang, G.S. (2006). Usefulness of Andigena (Solanum tuberosum ssp. andigena) 481
genotypes as parents in breeding early bulking potato cultivars. Euphytica, 150:107-482
115. 483
Lambert, S.J. (2008). The expansion of sustainability through New Economic Space : Māori 484
potatoes and cultural resilience. PhD, Lincoln University, Lincoln, Canterbury. 485
Lister, C. (2001). More benefits from spuds. Grower. Grower, 56:36-37. 486
Martin, R.J., Thomas, S.M., Stevens, D.R., Zyskowski, R.F., Moot, D.J., & Fraser, T.J. 487
(2006). Improving water use efficiency on irrigated dairy farms in Canterbury. 488
Proceedings of New Zealand Glassland Association, 68: 155-160. 489
21
McFarlane, T.R. (2007). The contribution of taewa (Maori potato) production to Maori 490
sustainable development. Master of Applied Science Dissertation, Lincoln University, 491
Lincoln 7647, New Zealand, Canterbury. 492
McKenzie, B.A. (1999). Processed and new crops. In James White & J. Hodgson (Eds.), New 493
Zealand Pasture and Crop Science. Auckland, New Zealand: Cambridge University 494
Press, UK. 495
McLaughlin, S.P. (1985). Economic prospects for New crops in Southern United States 496
Economic Botany, 39(4):475-481. 497
Meier, U. (2006). A note on the power of Fisher's least significant difference procedure. 498
Pharmaceutical Statistics, 5(4):253-263. 499
Molden, D., Sakthivadivel, R., & Habib, Z. (2001). Basin-level use and productivity of water: 500
examples from South Asia. Research Report 49. IWMI, Colombo. 501
Morison, J.I.L., Baker, N.R., Mullineaux, P.M., & Davies, W.J. (2007). Improving water use 502
in crop production. Philosophical Transactions of the Royal Society, Biological 503
Sciences (2008) 363:639-658. 504
Premrov, A., Schulte, R.P.O., Coxon, C.E., Hackett, R and Richards, K.G. (2010). Predicting 505
soil moisture conditions for arable free draining soils in Ireland under spring cereal 506
crop production. Irish Journal of Agricultural and Food Research. Vol. 49, No. 2 507
(2010), pp. 99-113 508
Roskruge, N. (1999). Taewa Maori; their management, social importance and commercial 509
viability. A research report presented in partial fulfillment of the requirements of the 510
Diploma in Maori Resource Development, Institute of Natural Resources, Massey 511
University, Palmerston North, New Zealand. 512
Roskruge, N., Puketapu, A., & McFarlane, T.R. (2010). Pests and diseases of Taewa (Maori 513
potato) crops. A book published Institute of Natural Resources, Massey University, 514
Palmerston North 4442, New Zealand. http//printoline.massey.ac.nz 515
SAS. (2008). SAS Procedures Guide - Version 9.2 Edition. 516
Siddique, K.H.M., Tennant, D., Perry, M., & Belford, R. (1990). Water use and water use 517
efficiency of old and modern wheat cultivars in a Mediterranean-type environment. 518
Australian Journal of Agricultural Research, 41(3):431-447. 519
Singh, J., Kaur, L., McCarthy, O.J., Moughan, P.J., & Singh, H. (2008). Rheological and 520
tectural characteristics of raw and par-cooked Taewa (MaoriI Potatoes) of New 521
Zealand. Journal of Texture Studies, 39(3):210-230. 522
Steyn, J., Du Plessis, H., Fourie, P., & Hammes, P. (1998). Yield response of potato 523
genotypes to different soil water regimes in contrasting seasons of a subtropical 524
climate. Potato Research, 41(3):239-254. 525
Thompson, J., Griffin, D., & North, S. (2003). Improving water use efficiency of rice. ‘Final 526
Report Project 1204.’ CRC for Sustainable Rice Production, Yanco, Australia. 527
Trebejo, I., & Midmore, D.J. (1990). Effect of water stress on potato growth, yield and water 528
use in a hot and a cool tropical climate. The Journal of Agricultural Science, 529
114(03):321-334. 530
Voss, R., Phillips, H., Brittan, K., Carlson, H., Garrison, N., Gaskell, M., and Veerkamp, G. 531
(1999). New speciality potato varieties give farmers growing and marketing options. 532
California Agriculture, 53:16-20. 533
Walker, T.J. (1996). Patterns and implications of variety changes in potatoes. International 534
Potato Center Working Paper. Series No. 1994-3, Lima, Peru : International Potato 535
Center, Pp 54. 536
Wallace, J.S. (2000). Increasing agricultural water use efficiency to meet future food 537
production. Agriculture, Ecosystems & Environment, 82(1-3):105-119. 538
22
Walworth, J., & Carling, D. (2002). Tuber initiation and development in irrigated and non-539
irrigated potatoes. American Journal of Potato Research, 79(6):387-395. 540
Wolfe, D.W., Fereres, E., & Vos, R. (1983). Growth and yield response of two potato 541
cultivars to various levels of applied water. Irrigation Science, 3(4):211-222. 542
Yuan, B.-Z., Nishiyama, S., & Kang, Y. (2003). Effects of different irrigation regimes on the 543
growth and yield of drip-irrigated potato. Agricultural Water Management, 63(3):153-544
167. 545
Zebarth, B.J., Tarn, T., de Jong, H., & Murphy, A. (2008). Nitrogen use efficiency 546
characteristics of Andigena and diploid potato selections. American Journal of Potato 547
Research, 85(3):210-218. 548
Zebarth, B.J., Tai, G., Tarn, R., de Jong, & Milburn, P.H. (2004). Nitrogen use efficiency 549
characteristics of commercial potato cultivars. Canadian Journal of Plant Science, 550
84(2):589-598. 551
Zhang, X., Chen, S., Liu, M., Pei, D., & Sun, H. (2005). Improved water use efficiency 552
associated with cultivars and agronomic management in the North China Plain. 553
Agronomy Journal, 97(3):783-790. 554
Zoebl, D. (2006). Is water productivity a usefull concept in agricultural water management? 555
Agricultural Water Management, 84:265-273. 556
557
TABLES
Table 1 Yield and yield components for Taewa and modern potato cultivars under irrigation and
rain-fed conditions in 2009 2010 and 2010 - 2011
Water Regime/
Cultivars
Tubers
Plant-1
Mean
Tuber
Weight
(g)
Marketable
Tuber
Yield
(t ha-1)
Harvest
Index
(HI)
WUE
(kg ha-1 m3)
2009- 2010
Irrigation
Agria
15.7c
112.1a
38.5a
0.88a
10.3ab
Moonlight
18.4c
97.1a
45.9a
0.78a
11.8a
Moe Moe
25.9b
61.1b
45.4a
0.70b
9.4b
Tutaekuri
60.5a
13.7c
13.6b
0.50c
5.2c
Mean (n=16)
30.1
71.0
35.9
0.72
9.2
Rain-fed
Agria
17.1c
64.3a
27.2a
0.78a
10.9ab
Moonlight
17.4c
69.9a
27.6a
0.78a
12.9a
Moe Moe
31.5b
38.9b
24.1a
0.67b
12.1a
Tutaekuri
60.4a
15.1c
13.8b
0.56c
9.0b
Mean (n=16)
31.6
47.1
23.2
0.70
11.2
Significance
Cultivars
P<0.0001
P<0.0001
P<0.0001
P<0.0001
P<0.05
Water regime
Ns
P<0.001
P<0.001
Ns
P<0.01
Interaction
Cultivars
Ns
Ns
Ns
Ns
Ns
2010 - 2011
Cultivar
Agria
14.9b
70.01a
38.9a
0.80
12.4a
Moe Moe
15.9b
39.4b
22.2b
0.48
6.1b
Tutaekuri
28.1a
16.2c
14.7c
0.47
4.5c
Significance
P<0.0001
P<0.0001
P<0.0001
P<0.0001
P<0.0001
Water regime
FI
20.3a
45.2a
29.7a
61.5
7.0b
PI
21.4a
41.4ab
26.1b
60.1
8.0a
Rain-fed
17.2b
39.1b
20.0c
54.2
7.9a
Significance
P<0.05
P<0.0001
P<0.001
P<0.001
Nitrogen levels
80
21.3a
47.8
27.2a
62.4
8.3a
240
17.9b
41.0
23.3b
54.8
7.0b
Significance
Ns
P<0.0001
P<0.0001
P<0.0001
cv.(%)
16.3
20.4
14.1
10.6
-
Interactions
Cultivar*WR
P<0.0001
Ns
P<0.0001
P<0.01
P<0.01
Cultivar*N
P<0.01
P<0.05
P<0.0001
P<0.001
P<0.0001
WR*N
Ns
Ns
Ns
P<0.05
Ns
Tables
Click here to download Tables: TABLES.docx
WR*Cultivar.*N
Ns
Ns
P<0.01
P<0.01
P<0.01
Note: FI refers to full irrigation whereas PI is partial irrigation, WR is water regime, N is
nitrogen. The columns with the same letters within the water regime treatments are not
statistically different (LSD0.05).
Table 2 Potato psyllid scores, nitrogen use efficiency (NUE) and economic water productivity
(EWP) (NZ$/m3) for Taewa and modern potato cultivars under different water and
nitrogen regimes, 2010/2011
Water regime
/Cultivar
Potato
Psyllid
NUE
(Kg kgN-1)
Economic water
Productivity
(NZ$/m3)
110 DAP
140 DAP
Potato cultivars (n=24)
Agria
2.8a
3.4a
373.2a
14.96b
Moe Moe
0.54b
3.3a
257.7b
19.32a
Tutaekuri
0.31b
2.8b
184.9c
12.98c
Significance P<0.0001
P<0.05
P<0.0001
P<0.0001
Water regimes (n=24)
FI
1.2
3.7a
313.5a
14.6b
PI
1.1
3.0b
277.6b
17.0a
Rain-fed
1.2
2.7b
224.8c
15.7ba
Significance
Ns
P<0.05
P<0.0001
P<0.01
Nitrogen (n=36)
80
1.1
2.6b
425.9a
18.0a
240
1.3
3.6a
118.0b
13.6b
Significance
Ns
P<0.0001
P<0.0001
P<0.0001
Interactions
Water regime*Cultivar
Ns
P<0.001
P<0.0001
P<0.001
Cultivar*N
Ns
P<0.05
P<0.0001
P<0.0001
Water regime*N
Ns
Ns
P<0.01
Ns
Water regime*Cult.*N
Ns
Ns
P<0.05
Ns
1
FIGURES
(a) = 2009/2010
(b) = 2010/2011
Figure 1 Cumulative rainfall (mm), cumulative crop evapotranspiration (mm), monthly
average maximum and minimum temperatures (Co) for the experimental site
during the experiment period from November 2009 to June 2010
Figure
2
Figure 2(a) Volumetric soil moisture (%)
change in Taewa and modern potato
under irrigation and rain-fed
conditions in 2009/2010. Error bar
represents ±SEM.
Figure 3(b) Change in volumetric soil
moisture content (%) for water
regime overtime in 2010/2011.
3
Figure 3 Interaction between cultivars and water regime on total tuber yield (t ha-1) in
2009/2010. Error bar represents ±SEM.
4
Figure 4 (a) Interaction between water regime*cultivar; (b) interaction between cultivar *
nitrogen, on number of tubers per plant: Error bar represents ±SEM.
5
Figure 5 Interaction between nitrogen and potato on mean tuber weight (g). Error bar
represents ±SEM.
Figure 6 Interaction between water regime
and potato cultivars. (Error bar
represents ±SEM.
Figure 7 Interaction between cultivars,
irrigation and nitrogen regime on total
tuber yield (t ha-1). Error bar represents
±SEM.
6
Figure 8 Interaction between cultivars,
irrigation and N regime on WUE
(kg ha-1 m3). Error bar represents
±SEM.
Figure 9 Interaction between cultivars,
irrigation and N regimes on NUE
(KgN kg-1). Error bar represents
±SEM.
7
Figure 10 Average numbers of potato psyllids (PP), per trap monitored in Manawatu region,
during the 2009/2010 and 2010/2011 growing season (Sourced from
http://www.potatoesnz.co.nz/Overview/What-we-are-working-on/Psyllid-
resources.htm), Potato New Zealand.
... The potato's seasonal evapotranspiration was estimated at 580 and 645 mm in a fine sandy-loam soil based on the soil water balance method under soil moisture sensorbased irrigation scheduling, while satellite-retrieved potato evapotranspiration averaged 570 mm [33]. The potential water requirement for modern potatoes (recently developed) was about 491 to 550 mm, whereas heritage potatoes (old Southern America native potato cultivars called specialty potatoes) had a higher water requirement of 610 to 611 mm due to their longer maturity period than modern potatoes [44]. For processing potato cultivars, the maximum shoot growth stage (62-86 DAS) was most susceptible to water stress, with over 40% water consumed during that phase [45]. ...
... The application of N fertilizers through drip fertigation on very light soils in Poland increased the NUE from 305 to 337 kg ha −1 per kg of N compared to the broadcasting of N fertilizers [115]. Though modern potatoes respond better to irrigation and nitrogen application, heritage potatoes are more tolerant to water and nitrogen-deficit conditions [44]. The effects of varying nitrogen rates and N application methods on potato tuber yield and NUE are presented in Table 2. ...
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Citation: Shrestha, B.; Darapuneni, M.; Stringam, B.L.; Lombard, K.; Djaman, K. Irrigation Water and Nitrogen Fertilizer Management in Potato (Solanum tuberosum L.): A Review. Agronomy 2023, 13, 2566. Abstract: Intensive irrigation and nutrient management practices in agriculture have given rise to serious issues in aquifer water depletion and groundwater quality. This review discusses the effects of irrigation and nitrogen management practices on potato growth, yield, and quality, and their impacts on water and nitrogen use efficiencies. This review also highlights the economics and consequences of applying deficit irrigation strategies in potato production. Many researchers have demonstrated that excessive irrigation and nitrogen application rates negatively impact potato tuber yield and quality while also increasing nitrate leaching, energy consumption, and the overall costs of production. An application of light-to-moderate deficit irrigation (10-30% of full irrigation) together with reduced nitrogen rates (60-170 kg/ha) has a great potential to improve water and nitrogen use efficiencies while obtaining optimum yield and quality in potato production, depending on the climate, variety, soil type, and water availability. There is an opportunity to reduce N application rates in potato production through deficit irrigation practices by minimizing nitrate leaching beyond the crop root zone. The best irrigation and nitrogen management techniques for potato production, as discussed in this review, include using sprinkle and drip irrigation techniques, irrigation scheduling based on local crop coefficients, soil moisture content, and crop modeling techniques, applying slow-release nitrogenous fertilizers, split nitrogen application, and applying water and nitrogenous fertilizers in accordance with crop growth stage requirements.
... The application of mulch and cultivar selection to improve potato WP in different agroecological zones has been reported by a handful of studies [18,19,20], [11]. Despite the solution being put forward such that when using practices solely tends to give small investment returns, for instance, mulch alone does not always guarantee increases because it is scenario-specific (e.g weed control, soil improvement, plant health, moisture retention, etc.) each scenario may require different types of mulch. ...
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Unevenly distributed rainfall leads to reduced potato water productivity (WP) under rainfed production. Understanding practices that can increase WP is vital. Objectives were to (i) understand seasonal variables that influence WP under rainfed conditions and (ii) the effect of the integration of cultivar, locality, mulch on potato WP. The study was under two agroecological zones Appelsbosch (Mbalenhle locality), and Swayimane (Stezi, and Mbhava locality), under smallholder. A split plot, in a randomized complete block design experiment, consists of mulching (mulch and not mulch), and selected cultivars. Soil water content (SWC), yield, and climatic conditions were collected, water use (ET) and WP were calculated. Rainfall, ET, and SWC had a significant influence on seasonal WP. Cultivar x mulch x locality had an insignificant effect on WP, however, locality x cultivars significantly altered potato WP. Localities that had lower vapor pressure deficit (VPD), low relative humidity, and sandy soil had higher potato WP of 14.53 kg m-3. The findings suggest that localities that have less atmospheric dryness and cultivars that show stability of yield across seasons can be an easy-to-apply practice for increasing potato WP under a resource-limited environment. Mulch is important when the distribution of intra-annual rainfall does not match crop water requirements.
... The application of mulch and cultivar selection to improve potato WP in different agroecological zones has been reported on by a handful of studies [9,10,[18][19][20]. Despite the solution being put forward, the practices mentioned tend to give small investment returns when individually applied. ...
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Unevenly distributed rainfall leads to reduced potato water productivity (WP) under rainfed production conditions. Understanding the practices that can increase WP is vital. Our objectives were to understand (i) the seasonal variables that influence WP under rainfed conditions and (ii) the effect of the integration of cultivar x locality x mulch on potato WP. The study was undertaken in smallholder settings in two agroecological zones: Appelsbosch (Mbalenhle locality) and Swayimane (Stezi and Mbhava locality). A split plot, in a randomized complete block design experiment, included mulching (mulch and no mulch), four selected cultivars, and s three localities. Soil water content (SWC), yield, and climatic data were collected, and actual crop evapotranspiration (ETa) and WP were calculated. Rainfall, ETa, and crop growth and development had a significant influence on the seasonal WP. Cultivar × mulch × locality had an insignificant effect on the WP, however, locality × cultivar significantly altered the WP. The localities that had lower vapor pressure deficit (VPD), high relative humidity, and sandy soil had a higher potato WP for all cultivars, with the highest (18.38 kg m −3) being that from Electra. The findings suggest that using localities that have less atmospheric dryness and a cultivar (Electra) that shows stability of yield across the seasons can be an easy-to-apply practice for increasing potato WP in a resource-limited environment.
... The consistency in achieving elevated yields can be attributed to the cultivar's inherent genetic traits that equip it with robust growth capabilities [38,39]. These traits may encompass efficient water utilization, nutrient uptake, and adaptability to diverse environmental conditions [6,40,41]. Similar findings were obtained by Ilin et al. [36], who investigated the effects of irrigation on the yield of the Desire potato cultivar meant for mashed potatoes. In this study, applying different N and K fertilizers to various cultivars significantly influenced yield. ...
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Potatoes are essential for chip production, requiring high quality for processors and high yields for farmers. This two-year study was carried out for the purpose of investigating the influence of irrigation, fertilization, and cultivar on potato yield and tuber and chip quality. Field experiments were conducted in Sombor, Serbia, using a split-split plot design with three replications. Whole-plot treatments involved two irrigation schemes: sprinkler irrigation (SI) used as standard (control) and drip irrigation (DI). Subplot treatments included nitrogen (N) and potassium (K) fertilization in four different combinations: 64 kg N/ha and 64 kg K/ha (N 64 K 64) as control; 77 kg N/ha and 110 kg K/ha (N 77 K 110); 90 kg N/ha and 156 kg K/ha (N 90 K 156); and 103 kg N/ha and 202 kg K/ha (N 103 K 202). Sub-subplots comprised three cultivars: VR-808; Pirol; and Brooke. The VR-808 cultivar consistently yielded the highest amount (25.6 and 24.9 t/ha) under both irrigation methods. DI raised tuber flesh temperature compared to SI. The N 90 K 156 × Pirol interaction exhibited the highest number of tubers with defects, while N 90 K 156 × VR-808 had the fewest. Under DI, the VR-808 cultivar produced chips with the highest total defects, whereas Brooke had the lowest. The postfrying palm oil temperature was the highest for N 64 N 64 × Brooke and the lowest for N 110 K 220 × Pirol. This study underscores the role of irrigation, fertilization, and cultivar in achieving high yields and high chip quality, providing valuable insights into the whole process, from field to chip bag.
... The WUE R+I and WUE ET observed for all fields were similar to values reported by Machakaire et al. [47] (163-189 kg mm −1 ) for potato produced under comparable conditions. Similarly, a WUE R+I above 116 kg mm −1 has been reported for other modern potato varieties elsewhere [61,62]. ...
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Estimating crop coefficients and evapotranspiration (ET) accurately is crucial for optimizing irrigation. Remote sensing techniques using green canopy cover, leaf area index (LAI), and normalized difference vegetation index (NDVI) have been applied to estimate basal crop coefficients (Kcb) and ET for different crops. However, analysis of the potential of these techniques to improve water management in irrigated potato (Solanum tuberosum L.) is still lacking. This study aimed to assess the modified nonlinear relationship between LAI, Kcb and NDVI in estimating crop coefficients (Kc) and ET of potato. Moreover, Kc and ET were derived from the measured fraction of green canopy cover (FGCC) and the FAO-56 approach. ET estimated from the FAO-56, FGCC and NDVI approaches were compared with the ET simulated using the LINTUL-Potato model. The results showed that the Kc values based on FGCC and NDVI were on average 0.16 lower than values based on FAO-56 Kc during the mid-season growing stage. ET estimated from FAO-56, FGCC and NDVI compared well with ET calculated by the LINTUL-Potato model, with RMSE values of 0.83, 0.79, and 0.78 mm day−1, respectively. These results indicate that dynamic crop coefficients and potato ET can be estimated from canopy cover and NDVI. The outcomes of this study will assist potato growers in determining crop water requirements using real-time ETo, canopy state variables and NDVI data from satellite images.
... In arid and semi-arid areas, exploring the interaction between water and fertilizer is conducive to maximizing the resources use efficiency. In recent years, many studies have explored the coupling effects of irrigation level and nitrogen (Fandika et al., 2016;Zhou et al., 2016;Yang et al., 2017), phosphorus (Sun et al., 2015), or potassium (Ati et al., 2012;Zhang et al., 2022) rates on potato growth, yield, quality, water and fertilizer use efficiency, and have recommended water and fertilizer supply strategies for potato production. However, few studies have focused on the coupling effects of irrigation level and nitrogen, phosphorus and potassium rates on biomass, nutrient absorption, fertilizer use efficiency and tuber yield of potato under drip-fertigation. ...
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Background The pervasively imprudent practices of irrigation and nitrogen (N) application within Oasis Cool Irrigation zones have led to significant soil nitrogen loss and a marked decrease in water and nitrogen use efficiency. Methods To address this concern, a comprehensive field experiment was conducted from April to September in 2023 to investigate the impact of varying degrees of water and fertilization regulation strategies on pivotal parameters including potato yield, quality, nitrogen balance, and water-nitrogen use efficiency. The experimental design incorporated two water deficit degrees at potato seedling (W1, 55%-65% of Field Capacity (FC); W2, 45%-55% of FC), and four distinct nitrogen application gradients (N0, 0 kg ha-1 of N; N1, 130 kg ha-1 of N; N2, 185 kg ha-1 of N; N3, 240 kg ha-1 of N). A control was also included, comprising N0 nitrogen application and full irrigation (W0, 65%-75% of FC), totally eight treatments and one check. Results The results indicated that the tuber yield, plant dry matter accumulation, plant height, plant stem, and leaf area index increased with higher nitrogen fertilizer application and irrigation volume. However, tuber starch content, vitamin C, and protein content initially increased and then decreased, while reducing sugar content consistently decreased. Except for W1N2 treatment, the irrigation water use efficiency increased as the N application rate rose, while the nitrogen partial factor productivity, crop nitrogen use efficiency and soil nitrogen use efficiency decreased with an increase in N fertilizer application. The W1N2 treatment resulted in a higher yield (43.16 t ha-1), highest crop nitrogen use efficiency (0.95) and systematic nitrogen use efficiency (0.72),while maintaining moderate levels of soil nitrate and ammonium nitrogen. Conclusion Therefore, through the construction of an integrated evaluation index (IEI), the W1N2 treatment of mild water deficit (55%-65% of FC) at potato seedling combined with the medium nitrogen application (185 kg ha-1 of N) has the highest IEI (0.978), it was recommended as the optimal water-nitrogen regulation and management strategies to facilitate high-yield, high-efficiency, and environmentally sustainable potato production in the cold and arid oasis areas of northwest China.
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To maximise the throughput of novel, high-throughput phenotyping platforms, many researchers have utilised smaller pot sizes to increase the number of biological replicates that can be grown in spatially limited controlled environments. This may confound plant development through a process known as “pot binding”, particularly in larger species including potato (Solanum tuberosum), and under water-restricted conditions. We aimed to investigate the water availability hypothesis of pot binding, which predicts that small pots have insufficient water holding capacities to prevent drought stress between irrigation periods, in potato. Two cultivars of potato were grown in small (5 L) and large (20 L) pots, were kept under polytunnel conditions, and were subjected to three irrigation frequencies: every other day, daily, and twice daily. Plants were phenotyped with two Phenospex PlantEye F500s and canopy and tuber fresh mass and dry matter were measured. Increasing irrigation frequency from every other day to daily was associated with a significant increase in fresh tuber yield, but only in large pots. This suggests a similar level of drought stress occurred between these treatments in the small pots, supporting the water availability hypothesis of pot binding. Further increasing irrigation frequency to twice daily was still not sufficient to increase yields in small pots but it caused an insignificant increase in yield in the larger pots, suggesting some pot binding may be occurring in large pots under daily irrigation. Canopy temperatures were significantly higher under each irrigation frequency in the small pots compared to large pots, which strongly supports the water availability hypothesis as higher canopy temperatures are a reliable indicator of drought stress in potato. Digital phenotyping was found to be less accurate for larger plants, probably due to a higher degree of self-shading. The research demonstrates the need to define the optimum pot size and irrigation protocols required to completely prevent pot binding and ensure drought treatments are not inadvertently applied to control plants.
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Irrigation, fertilization, and variety are important factors affecting potato production in northwest China. Field experiments (2021 and 2022) were performed to investigate the effects of irrigation and fertilization on the plant growth and soil microbial population of different potato varieties. Three irrigation levels were used, i.e., 100% ETc (W1), 80% ETc (W2), and 60% ETc (W3), with ETc standing for crop evapotranspiration. Three fertilization levels were used (N-P-K), i.e., 240-120-300 kg ha−1 (F1), 180-90-225 kg ha−1 (F2), and 120-60-150 kg ha−1 (F3). Three variety types were used, i.e., Feiurita (V1), Longshu 7 (V2), and Qingshu 9 (V3). These factors significantly influenced tuber yield (TY), net income (NI), and water productivity (WP). TY, NI, WP, total nitrogen accumulation (TNA), and nitrogen use efficiency (NUE) peaked at F2. Fertilization significantly impacted soil bacteria quantity (SBQ), fungi quantity (SFQ), and actinomycetes quantity (SAQ). TY, NI, SBQ, SFQ, and SAQ were highest at W2. Soil microbial population was strongly correlated with TY, NI, WP, TNA, and NUE. Comprehensively, this study suggests that irrigation that is varied from 248 to 266 mm, and fertilization (N-P-K) that is varied from 149.09-74.55-186.36 to 212.73-106.36-265.91 kg ha−1 can promote the potato industry’s sustainable development and provide important references for the optimal field management of potato cultivation in northwest China.
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One approach for reducing the contribution of potato (Solanum tuberosum L.) production to nitrate contamination of groundwater is to develop cultivars which utilize N more efficiently. In this study, variation in N use efficiency (NUE; dry matter production per unit crop N supply) characteristics of 20 commercial potato cultivars of North American and European origin were evaluated in 2 yr. Cultivars were grown with or without application of 100 kg N ha -1 as ammonium nitrate banded at planting. The recommended within-row spacing was used for each cultivar and no irrigation was applied. Plant dry matter and N accumulation were determined prior to significant leaf senescence. Crop N supply was estimated as fertilizer N applied plus soil inorganic N measured at planting plus apparent net soil N mineralization. Nitrogen use efficiency decreased curvilinearly with increasing crop N supply. Nitrogen use efficiency was lower for early-maturing cultivars compared to mid-season and late-maturing cultivars. A curvilinear relationship was obtained between plant dry matter accumulation and plant N accumulation using data for all cultivars. Deviations from this relationship were interpreted as variation in N utilization efficiency (NUtE; dry matter accumulation per unit N accumulation). Significant differences in NUtE were measured among cultivars of similar maturity. Nitrogen uptake efficiency (NUpE; plant N content per unit crop N supply) and soil nitrate concentration measured at plant harvest were uniformly low for all cultivars when crop N supply was limited, but varied among cultivars when N was more abundant. This suggests that potato cultivars vary more in terms of N uptake capacity (plant N accumulation in the presence of an abundant N supply) than in terms of NUpE.
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California's small-scale farmers and direct marketers lead the nation in production of specialty potatoes, primarily yellow-fleshed types. Currently, limited varieties are available to meet the requirements for direct-marketing, organic production and perceived high consumer quality parameters such as flavor. During the 1990s, UC Davis and UC Cooperative Extension collaborated with farmers throughout California to conduct trials to identify the most desirable or profitable varieties among existing and potential new specialty potato varieties. Many European varieties are superior in yield and may be equal in quality to standard varieties. Specialty potato varieties with a diversity of yield potential, tuber size distribution, maturity and flesh-color intensity are available for conventional or alternative production and marketing systems. Consumer evaluations indicate variable preferences for color, taste, texture and other quality parameters. No general conclusions can be made about consumer preference for varieties.
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This chapter provides a review of work done at the International Potato Center (CIP) on improving water productivity in potato. Generally, potato is shallow-rooted and sensitive to even mild water deficits. Most of CIP's work related to water productivity was done in the 1980s as part of a research pro-gramme to develop improved germplasm and agronomic practices for potato production in warm tropi-cal environments. Heat-tolerant as well as drought-tolerant materials were selected and tested under a range of warm climates, with studies conducted to quantify evapotranspiration, stomatal conductance, leaf water potential, soil water dynamics and root growth. These same parameters were also determined in agronomic field experiments designed to quantify the effects of mulching, intercropping and close plant spacing on yield and water-use efficiency. Although needed, similar detailed studies on water-pro-ductivity components have yet to be done for potato grown more commonly in cooler environments at high altitudes in the tropics.
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The importance of yield improvement at farm conditions is highly dependent on the interaction between genotype and environment. The aim of the present work was to assess the attainable yield of a traditional and a modern malting barley cultivar growing under a wide range of soil nitrogen (N) availabilities and different water scenarios (low, intermediate and high rainfall conditions during the fallow period and throughout the crop cycle) considering a 25-year climate dataset for two sites (a shallow and a deep soil) in the Pampas, Argentina. For that purpose, a barley model was first calibrated and validated and then used to expand field research information to a range of conditions that are not only much wider but also more realistic than experiments on experimental farms. Yield of the modern cultivar was at least equal to (under the lowest yielding conditions) or significantly higher (under most growing conditions) than that of the traditional cultivar. Averaged across all the scenarios, yield was ~20% higher in the modern than in the traditional cultivar. The average attainable yield represented 42% of the yield potential in the shallow and 79% in the deep soil profiles. Yield advantage of the high yielding cultivar was based on using N more efficiently, which not only determined higher attainable yields but also reduced the requirements of soil N to achieve a particular yield level. Farmers would face little risk in adopting higher yielding cultivars in both high and low yielding environments and even in the latter ones N fertilisation could be beneficial in most years.
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Temporal prediction of soil moisture and evapotranspiration has a crucial role in agricultural and environmental management. A lack of Irish models for predicting evapotranspiration and soil moisture conditions for arable soils still represents a knowledge gap in this particular area of Irish agro-climatic modelling. The soil moisture deficit (SMD) crop model presented in this paper is based on the SMD hybrid model for Irish grassland (Schulte et al., 2005). Crop and site specific components (free-draining soil) have been integrated in the new model, which was calibrated and tested using soil tension measurements from two experimental sites located on a well-drained soil under spring barley cultivation in south-eastern Ireland. Calibration of the model gave an R² of 0.71 for the relationship between predicted SMD and measured soil tension, while model testing yielded R² values of 0.67 and 0.65 (two sites). The crop model presented here is designed to predict soil moisture conditions and effective drainage (i.e., leaching events). The model provided reasonable predictions of soil moisture conditions and effective drainage within its boundaries, i.e., free-draining land used for spring cereal production under Irish conditions. In general, the model is simple and practical due to the small number of required input parameters, and due to model outputs that have good practical applicability, such as for computing the cumulative amount of watersoluble nutrients leached from arable land under spring cereals in free-draining soils.
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Yield response to irrigation of different crops is of major importance in production planning where water resources are limited. This study aims to determine the effect of different irrigation methods and irrigation regimens on potato yield in the Trakya Region, Turkey, during 2003 and 2005. Potato was grown under furrow and drip irrigation methods and three regimens: irrigation applied when 30, 50, or 70% of the available water was consumed. The seasonal potato evapotranspiration ranged on 501 to 683 mm in 2003, and 464 to 647 mm in 2005. The furrow and drip irrigation methods had no significant effect on tuber yield for both years. Irrigation regimens influenced tuber yield (P < 0.05) in 2005, and the highest tuber yield was registered for 30% irrigation regimen, reaching 35.13 t ha-1 in 2003, and 44.56 t ha-1 in 2005. Water use efficiency values increased from 4.70 to 6.63 kg m-3 for furrow-irrigated treatments, and from 5.19 to 9.47 kg m-3 for drip-irrigated treatments.
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Modern potato cultivars (Solanum tuberosum L.) require high rates of fertilizer nitrogen (N). This practice is costly and can pose a serious threat to surface and groundwater. Previous evaluation of wild potato germplasm demonstrated the existence of species capable of producing high total biomass under low N conditions, with the ability to make maximum use of added N. Therefore, a two-year field experiment was conducted in 1994 and 1995 to investigate the response of selected wild potato accessions and their hybrids with the haploid USW551 (USW) to low and high N environments. The haploid USW and cultivars Russet Burbank, Red Norland, and Russet Norkotah were also included in the study. Uniform propagules and seedlings from the variousSolanum species were transplanted to a Hubbard loamy sand (Udic Haploboroll) at Becker, Minn. and were subjected to two N treatments: 0 and 225 kg N ha-1. At harvest, total dry biomass of wild and hybrid potato germplasm was equal to or higher than that of the cultivars. However, cultivar biomass partitioning was 1% to roots, 15% to shoots, 0% to fruits, and 84% to tubers, whereas wild potato species partitioned 18% to roots plus nontuberized stolons, 52% to shoots, 23% to fruits, and only 7% to tubers. Hybrids were intermediate, allocating 9% of their biomass to roots plus nontuberized stolons, 39% to shoots, 14% to fruits, and 38% to tubers. Nitrogen use efficiencies for many of the species and crosses were comparable to that for Russet Burbank and greater than those for Red Norland and Russet Norkotah. Of the wild species tested,S. chacoense accessions had the highest biomass accumulation and N uptake efficiencies and may be the best source of germplasm for improving NUE in a potato breeding program.
Article
Both winter wheat (Triticum aestivum L.) and maize (Zea mays L.) are the two staple crops of the North China Plain (NCP) that are combined in a single-year rotation. While annual evapotranspiration increased slightly, field studies conducted at Luancheng Station indicated that crop yield improved by 50% and resulted in significant water use efficiency (WUE) increases from 1982 to 2002. Water use efficiency has improved from 10 to 15 kg mm(-1) ha(-1) for winter wheat and from 14 to 20 kg mm(-1) ha(-1) for maize in the Piedmont of Mt. Taihang in the NCP. Yield increase was associated with the increase in kernel numbers per unit area without alteration of the weight of the kernels for both winter wheat and maize. Number of kernels per spike of winter wheat was increased from about 22 for cultivars used in 1980s to about 28 for cultivars used presently. Number of kernels per ear of maize was increased from about 300 for cultivars used in 1980s to about 450 presently. From the early 1990s, combine had been used to harvest winter wheat, allowing straw mulch to be applied to maize. Measurements of WUE from 1987 to 1992 and again from 1997 to 2002 showed that WIDE of maize under mulch was significantly higher than that without mulch. Mulching reduced soil evaporation loss by 40 to 50 mm per annum measured by microlysimeters, and WUE was averagely improved 8 to 10% for the 12 seasons. An improvement in irrigation scheduling had also improved WUE. Irrigation applications to winter wheat were reduced from about eight in 9 times in 1980s to about four times presently. Field tests from 1999 to 2004 still showed that reducing the present number of seasonal wheat irrigations to either three, two, or one depending on seasonal rainfall would benefit both grain production and WUE of winter wheat.