H. Pathak

Indian Agricultural Research Institute, New Dilli, NCT, India

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Publications (126)190.32 Total impact

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    ABSTRACT: Trend analysis of hydro-climatic variables such as streamflow, rainfall, and temperature provides useful information for effective water resources planning, designing, and management. Trends in observed streamflow at four gauging stations in the Gomti River basin of North India were assessed using the Mann–Kendall and Sen’s slope for the 1982 to 2012 period. The relationships between trends in streamflow and rainfall were studied by correlation analyses. There was a gradual decreasing trend of annual, monsoonal, and winter seasonal streamflow (p<0.05) from the midstream to the downstream of the river and also a decreasing trend of annual streamflow for the 5-year moving averaged standardized anomalies of streamflow for the entire basin. The declining 26 trend in the streamflow was attributed partly to the increased water withdrawal, to increased air temperature, to higher population, and partly to significant reducing trend of post monsoon rainfall especially at downstream. Upstream gauging station showed a significant increasing trend of streamflow (1.6 m3/s/year) at annual scale, and this trend was attributed to the significant increasing trend of catchment rainfall(9.54 mm/year). It was further evident in the significant coefficient of positive correlation (ρ=0.8) between streamflow and catchment rainfall. The decreasing trend in streamflow and post-monsoon rainfall especially towards downstream area with concurrent increasing trend of temperature indicates a drying tendency of the Gomti River basin over the study period. The results of this study may help stakeholders to design streamflow restoration strategies for sustainable water management planning of the Gomti River basin.
    Theoretical and Applied Climatology 03/2015; DOI:10.1007/s00704-015-1390-5 · 1.74 Impact Factor
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    ABSTRACT: Calcium acts as a signaling molecule and plays very important role in plants-tolerance to the abiotic stresses including the heat stress. We studied the effect of exogenous Ca2+ (10 mM) prior to the heat stress (42 °C, 2 h) on different molecular and biochemical parameters associated with thermotolerance in wheat (Triticum aestivum). We could observe 64 and 52 unique protein spots in HD2967 (thermotolerant) and HD2329 (thermosusceptible) cultivars under normal and heat stress condition. Similarly, 13 and 9 (HD2967) and 19 and 9 proteins (HD2329) were observed to be up-regulated and down-regulated in response to HS. MALDI-TOF-TOF/MS characterization identified the differentially expressed protein (DEP) spots as calcium dependent protein kinase (CDPK), oxygen evolving enhancer protein, HSP17, HSP70, Rubisco activase etc. Transcript profiling of identified stress-associated genes (SAGs) showed very high expression of CDPK, HSFA4a, HSP17, SOD and APX in response to Ca2+ + HS in HD2967 compared to HD2329 cultivars of wheat. Similarly accumulation of signaling molecules (H2O2 and CDPK) as well as osmolyte was observed maximum in response to Ca2+ + HS in HD2967 compared to HD2329 cultivars. Very high activities of guaiacol-peroxidase and ascorbate peroxidase were observed in Ca-treated HD2967 compared to HD2329 when exposed to HS. It is the abundance of these chaperones and antioxidant enzymes in thermotolerant cultivar which limit the accumulation of H2O2 in response to Ca2+ and HS. Exogenous Ca2+ application showed negative correlation with lipid peroxidation and positive correlation with total antioxidant capacity of the cell system under the elevated temperature. Alteration in Ca2+ efflux triggers the activities of kinases and peroxidases more in tolerant compared to susceptible cultivars which regulate the accumulation of ROS inside the cell and attenuate the lipid peroxidation process. Ultimately, it enhances the total antioxidant capacity and thermotolerance of the plants under the heat stress.
    Journal of Plant Biochemistry and Biotechnology 01/2015; DOI:10.1007/s13562-014-0295-1 · 0.81 Impact Factor
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    ABSTRACT: Global warming refers to the current rise in the average temperature of earth's atmosphere and oceans owing to transmission of incoming shortwave radiation from the sun and absorbance of outgoing long-wave radiation from the earth. This has been aggravated by the building up of some gases such as carbon dioxide (CO 2), methane (CH 4), nitrous oxide (N 2 O), and chlorofluorocarbons (CFCs) (Table 1), which are collectively called greenhouse gases (GHGs). They inhibit the outgoing radiations from the earth and upset earth's heat balance. The accumulation of GHGs in atmosphere and the consequent rise in earth's temperature is termed as " greenhouse effect ". Greenhouse effect is a process in which absorption and emission of infrared radiation by gases in the atmosphere warm a planet's lower atmosphere and surface. It was proposed by Joseph Fourier in 1824 and was first investigated quantitatively by Svante Arrhenius in 1896. According to the world agency, InterGovernmental Panel on Climate Change (IPCC), the global mean annual temperature at the end of the 20th century was recorded to be higher by 0.40–0.76°C than that at the end of the 19th century (IPCC 2007), with about two-thirds of the increase occurring over just the last three decades. Scientists are certain that most of it is caused by increasing concentrations of GHGs produced by human activities. IPCC has projected a rise of 1.1–6.4°C in temperature by the end of the twenty-first century. 18.2 ENHANcED GREENHOUSE EffEct Owing to the greenhouse effect, warming of the lower atmosphere and surface of a planet takes place by a complex process involving sunlight, gases, and particles in the atmosphere. All bodies absorb as well as transmit energy. Radiations from the sun and earth closely resemble blackbody radiations. The earth's surface radiates most intensely near 10 µm at a mean surface temperature of 15°C. GHGs in the air can temporarily absorb thermal infrared light of specific wavelengths;
    Introduction to Environmental Sciences, Edited by R S Khoiyangbam and Navindu Gupta, 01/2015: chapter Greenhouse Gas Emission and Global Warming: pages 379-411; TERI Press., ISBN: 978-81-7993-455-5
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    ABSTRACT: MicroRNAs (miRNAs) are small endogenous RNAs of ~22 nucleotides that have been shown to play regulatory role by negatively affecting the expression of genes at the post-transcriptional level. Information of miRNAs on some important crops like soybean, Arabidopsis, and rice, etc. are available, but no study on heat-responsive novel miRNAs has yet been reported in wheat (Triticum aestivum L.). In the present investigation, a popular wheat cultivar HD2985 was used in small RNA library construction and Illumina HiSeq 2000 was used to perform high-throughput sequencing of the library after cluster generation; 110,896,604 and 87,743,861 reads were generated in the control (22 °C) and heat-treated (42 °C for 2 h) samples, respectively. Forty-four precursor and mature miRNAs were found in T. aestivum from miRBase v 19. The frequencies of the miRNA families varied from 2 (tae-miR1117) to 60,672 (tae-miR159b). We identify 1052 and 902 mature miRNA sequences in HD2985 control and HS-treated samples by mapping on reference draft genome of T. aestivum. Maximum identified miRNAs were located on IWGSC_CSS_3B_scaff (chromosome 3B). We could identify 53 and 46 mature miRNA in the control and HS samples and more than 516 target genes by mapping on the reference genome of Oryza sativa, Zea mays, and Sorghum bicolor. Using different pipelines and plant-specific criteria, 37 novel miRNAs were identified in the control and treated samples. Six novel miRNA were validated using qRT-PCR to be heat-responsive. A negative correlation was, however, observed between the expression of novel miRNAs and their targets. Target prediction and pathway analysis revealed their involvement in the heat stress tolerance. These novel miRNAs are new additions to miRNA database of wheat, and the regulatory network will be made use of in deciphering the mechanism of thermotolerance in wheat.
    Functional and Integrative Genomics 12/2014; DOI:10.1007/s10142-014-0421-0 · 2.69 Impact Factor
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    ABSTRACT: In recent years the importance of biochar application in soil has increased tremendously as pyrogenic carbon (C) may act as an important long-term C sink because its microbial decomposition and chemical transformation is very slow. Biochar was prepared from maize stover, pearl millet stalk, rice straw and wheat straw in a pyrolysis kiln at the temperature of 400 °C. The biochar was characterised for various physical, chemical and structural properties. The stability of biochar in soil was studied by CO 2 efflux for one year. The effect of biochar on available N, P, K and microbial properties was also studied in a separate experiment continued for 67 days. The wheat and rice biochar exhibited higher cation exchange capacity (CEC) than the other biochar materials, while the pH values of maize and pearl millet biochar were higher over rice and wheat biochar. The maize biochar was richer in C, N and P contents. The energy dispersive X-ray spectrometry (EDS) analysis showed that wheat and rice bio-char was richer in K and Si, respectively. Total C content was highest in maize biochar (66%) followed by pearl millet biochar (64%), wheat biochar (64%) and rice biochar (60%). The Fourier-transform infrared spectroscopy (FTIR) analysis showed the presence of various functional groups in biochar. The maize biochar exhibited stron-ger structural surface functional groups including aromatic C_C stretching. Among the four different biochar used for CO 2 efflux study, the maize biochar was found to be the most stable showing reduced C mineralization to protect the native soil organic C. The reduced C mineralization was also observed in the case of pearl millet and wheat biochar. Contrarily, rice biochar exhibited higher C mineralization. The maize biochar being most stable in soil showed highest C enrichment in soil. The maize biochar enhanced the available N and P in soil, while wheat biochar increased the available K content in soil. The rice biochar being relatively labile in soil fuelled the prolif-eration of microbial biomass and thereby enhancing the physiological efficiency of microbes measured in terms of dehydrogenase activity. Maize biochar with higher nutrient values especially N and P and C stability could be advocated for enhancing soil fertility and long-term C sequestration. Rice biochar might be advocated for higher microbial activities in restoring biological fertility of degraded soils.
    Geoderma 11/2014; 239-240(Feb 2015):293-303. DOI:10.1016/j.geoderma.2014.11.009 · 2.51 Impact Factor
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    The Journal of biological sciences 11/2014; DOI:10.1007/40011-014-0439-
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    ABSTRACT: Antioxidant enzymes, besides being involved in various developmental processes, are known to be important for environmental stress tolerance in plants. In this study, the effect of treatment of 2.5 mM putrescine (Put), heat stress (HS -42 degrees C for 2 h) and their combination on the expression and activity of antioxidant enzymes was studied at pre-anthesis in the leaves of two wheat (Triticum aestivum L.) cultivars--HDR77 (thermotolerant) and HD2329 (thermosusceptible). We observed that 2.5 mM Put before HS significantly enhanced the transcript levels of superoxide dismutase (SOD), catalase (CAT), cytoplasmic and peroxisomal ascorbate peroxidase (cAPX, pAPX) in both the cultivars. However, the activities of antioxidant enzymes (SOD, CAT, APX and GR), as well as accumulation of antioxidants (ascorbic acid and total thiol content) were higher in HDR77 than in HD2329 in response to the treatment 2.5 mM Put + HS. No significant change was observed in the proline accumulation in response to HS and combined treatment of 2.5 mM Put + HS. A decrease in the H2O2 accumulation, lipid peroxidation and increase in cell membrane stability (CMS) were observed in response to 2.5 mM Put + HS treatment, as compared to HS treatment alone in both the cultivars; HDR77 was, however, more responsive to 2.5 mM Put + HS treatment. Put (2.5 mM) treatment at pre-anthesis thus modulated the defense mechanism responsible for the thermotolerance capacity of wheat under the heat stress. Elicitors like Put, therefore, need to be further studied for temporarily manipulating the thermotolerance capacity of wheat grown under the field conditions in view of the impending global climate change.
    Indian journal of biochemistry & biophysics 10/2014; 51(5):396-406. · 1.08 Impact Factor
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    ABSTRACT: A field experiment was carried out at the farm of Indian Agricultural Research Institute, New Delhi to quantify the effect of elevated carbon dioxide (CO2) and different levels of N fertiliser application on nitrous oxide (N2O) and carbon dioxide (CO2) emissions from soil under maize. The experiment included five treatments: 60 kg N ha−1 under ambient CO2 (385 ppm) in open plots, 120 kg N ha−1 under ambient CO2 (385 ppm) in open plots, 160 kg N ha−1 under ambient CO2 (385 ppm) in open plots, 120 kg N ha−1 under ambient CO2 (385 ppm) in open top chambers (OTC) and 120 kg N ha−1 under elevated CO2 (500 ± 50 ppm) in the OTC. Peaks of N2O flux were observed after every dose of N application. Cumulative N2O emission was 13% lower under ambient CO2 as compared to the elevated CO2 concentrations. There was an increase in CO2 emissions with application of N from 60 kg ha−1 to 160 kg ha−1. Higher yield and root biomass was observed under higher N treatment (160 kg N ha−1). There was no significant increase in maize yield under elevated CO2 as compared to ambient CO2. The carbon emitted was more than the carbon fixed under elevated CO2 as compared to ambient CO2 levels. The carbon efficiency ratio (C fixed/C emitted) was highest in ambient CO2 treatment in the OTC.
    Experimental Agriculture 10/2014; 50(04):625-643. DOI:10.1017/S0014479714000118 · 1.07 Impact Factor
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    ABSTRACT: Based on the eddy covariance flux measurement in rice fields of northern India, net ecosystem exchange of carbon dioxide (NEE) was estimated in the kharif season (rainy season) of 2013. The daily NEE showed a seasonal variation and the carbon dioxide (CO2) flux fluctuated with in ±0.05 g C m-2 d-1 during the early vegetative stage. Thereafter there was net consumption of CO2 from late July until end of September. It was observed to be maximum with an uptake rate of -6.54 g C m-2 d-1 during booting reproductive stage. The rice fields acted as a CO2 source during early October when daily NEE turned positive around maturity stage, a few days before rice harvest because of declining photosynthetic activity and enhanced ecosystem respiration from almost dried soil. The mean and cumulative NEE over the rice growth period was -2.97 and -316.6 g Cm-2 d-1 respectively. The daily ecosystem respiration (Re) varied from 0.62 to 7.30 g C m-2 d-1 depending upon the crop growth stage. The mean Re and gross primary productivity (GPP) over the growing period was 4.00 and 7.23 g C m-2 d-1 respectively. Further investigations are needed to clarify seasonal and inter-annual variations in NEE in rice based cropping systems.
    Bridging Atmospheric Flux Monitoring to National and International Climate Change Initiatives, International Rice Research Institute (IRRI), Los Banos, Philippines; 08/2014
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    ABSTRACT: Crop water requirement (CWR) under the projected climate change could be mediated through changes in other weather parameters including the air temperature. The present study was directed to assess the on-farm water requirement in wheat crop in future, in semi-arid Indo-Gangetic Plains of India, through field and computer simulations. Field simulation using temperature gradient tunnels shows 18% higher crop evapotranspiration (ETc) and 17% increase in root water extraction at 3.6 °C elevated temperature compared to 1.5 °C increase over the ambient. A time series model (ARIMA) with long-term (1984–2010) weather data of the experimental site and a global climate model (IPCC-SRES HADCM3) were used to simulate the potential ET (ET0) of wheat for 2020–2021 and 2050–2051 years. The crop coefficient (Kc) values for these years were generated through Kc–CGDD (Cumulative growing-degree-days) relation by using LARS-WG model-derived daily minimum and maximum temperatures. The CWR and NIR (Net Irrigation Requirement) are likely to be less in projected years even though air temperatures increase. The CWR reduces in ARIMA outputs owing to a lower reference ET (ET0) due to decline in solar radiation. Under IPCC-SRES scenarios, the ETc–crop phenophase relation [CGDD–LGP (length of growing period) response] may offset the effect of rising temperature and a net decline in CWR is observed. It may be likely that the effect of temperature increase on CWR is manifested mostly through its relation with crop phenophase (thermal requirement to complete a specific growth stage) and not the temperature effect on ET0 per se. This is certainly a ray of hope in managing the depleting irrigation water resources in the semi-arid wheat-growing regions of the IGP.
    Agriculture Ecosystems & Environment 07/2014; 197:174–183. DOI:10.1016/j.agee.2014.07.023 · 3.20 Impact Factor
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    ABSTRACT: Climate is a very decisive factor in water resource availability of a region. Warming of the climate system in recent decades is evident from increase in global average air and ocean temperatures, widespread melting of snow and ice, and rising global sea level. The hydrological cycle is intimately linked with changes in atmospheric temperature and radiation balance. A warmer climate may lead to intensification of the hydrological cycle, resulting in higher rates of evaporation and increase of liquid precipitation. These processes, in association with a shifting pattern of precipitation, may affect the spatial and temporal distribution of runoff, soil moisture, groundwater reserves etc. and may increase the frequency of droughts and floods. Agricultural demand, particularly for irrigation water is considered more sensitive to climate change. A change in field-level climate may alter the need and timing of irrigation. Increased dryness may lead to increased demand, but demand may be reduced if soil moisture content rises at critical times of the year. It is projected that most irrigated areas in India would require more water around 2025 and global net irrigation requirements would increase relative to the situation without climate change by 3.5–5% by 2025, and 6–8% by 2075. The effect of climate change on water resources may be mitigated through better water harvesting through the creation of micro-storage facilities in watersheds. These would not only provide supplemental irrigation but also recharge the groundwater aquifers.
    Indian Journal of Agricultural Sciences 06/2014; 84(6):671-679. · 0.18 Impact Factor
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    ABSTRACT: Ammonia (NH3) emission from rice (July–October) and wheat (November–April) cropping system was measured using the chemiluminescence method at the subtropical agricultural land of Delhi, India during 2009–2010 and 2010–2011. The measurement was carried out from the canopy height (1.2–1.3 m) during the different growth stages of rice and wheat crops to quantify NH3 emission and assess the variations in emission during the crop growth stages. The background atmospheric concentration of NH3 was measured at 5 m height at the study site and subtracted from the NH3 concentration at crop canopy height to quantify the emission of NH3 from crops. The NH3 emission in wheat crops were 35.9 ± 6.3, 24.5 ± 5.5, 15.8 ± 4.5, 18.6 ± 3.9, and 20.8 ± 3.8 lg m-2 d-1 during sowing, crown root initiation, panicle initiation, grain filling, and maturity stages, respectively. In rice crops, the emissions during transplanting, tillering, panicle initiation, grain filling, and maturity stages were 29.7 ± 7.4, 16.2 ± 3.7, 19.0 ± 3.7, and 18.4 ± 3.9 lg m-2 d-1, respectively. The emission was higher during sowing/transplanting compared to other stages in both the crops. About 9 % of applied fertilizer N was emitted as NH3 from the rice–wheat cropping system in the subtropical soils of India.
    06/2014; DOI:10.1007/s40003-014-0107-9
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    ABSTRACT: Analysis of trends in hydro-climatic variables such as rainfall, temperature and stream flow provide useful information for planning of water resources, control of flood, management of drought and agricultural production. Trends in rainfall (1982-2011) and temperature (1972-2007) in districts of Gomti River basin were assessed using the Mann-Kendall and Sen’s slope estimator. Streamflow (1982-2012) at the downstream end of the basin, Maighat was also assessed and relationships between trends in streamflow and rainfall were evaluated. All the districts in the upstream area showed significant increasing trend in annual rainfall (p < 0.05) while downstream areas showed decreasing trend. A similar drift was observed in the monsoon rain. Pre-monsoon rains had increasing trend, particularly in the month of May. In contrast, post-monsoon and winter rainfall were significantly decreasing especially towards the downstream areas. Streamflow was also reducing irrespective of the scale of assessment and this could be attributed partly to the decreasing rainfall. Decrease in rainfall and consequent decline in streamflow of the basin along with increasing temperature indicate possibility of dryness in the lower basin over the years. The results of this study could be helpful in implementing adaptation and mitigation strategies for alleviating the environmental and livelihood threats in Gomti River basin.
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    ABSTRACT: Cotton–wheat cropping system is the second most important wheat based system in the South Asia (4.5 M ha) and India (2.6 M ha) and contributes significantly to the food security in the region. However, with the conventional method of crop establishment and crop management, the productivity and profitability of the cotton–wheat system is low. Hence, despite non-suitability of growing situations, farmers are inclined towards cultivating the conventionally tilled rice–wheat rotation which has got severe consequences on the natural resources as well as the future food security. Therefore, an attempt was made to develop and evaluate the performances (in terms of system productivity, water productivity and profitability) of conservation agricultural technologies (like permanent narrow and broad-bed planting and residue management under zero tillage) under an irrigated cotton–wheat system in the region. Treatments included farmers’ practice (conventional tillage and flat-bed sowing without residue recycling; CT), and four combinations of raised-bed planting and residue management under zero tillage (viz., narrow-bed and broad-bed sowing with and without crop residue retention) in the first year. During the second year onwards two additional treatments were included: flat-bed sowing under zero tillage with and without residue retention. Results indicate that mean (of last two years) seed cotton yield in the plots under zero tilled permanent broad-bed sowing with residue retention (PBB + R) was about 24 and 51% higher compared with zero tilled narrow-bed sowing without residue retention (PNB; 2.91 Mg ha−1) and CT plots (2.59 Mg ha−1), respectively. Similarly, plots under PBB + R had significantly higher mean (of last two years) wheat grain yield than flat-bed zero tilled (ZT) and CT plots. Unlike seed cotton yield, wheat grain yield was not affected by the treatments in the first year. In the second year, plots under PBB + R had about 9 and 11% higher wheat grain yield than PNB (4.37 Mg ha−1) and CT (4.29 Mg ha−1) plots, respectively. Although the system productivity in terms of wheat equivalent yield (WEY) was similar in the plots under PBB + R and zero tilled-broad permanent bed sowing without residue retention (PBB) and zero tilled narrow-bed sowing with residue retention (PNB + R) in the first year, plots under PBB + R had about 15 and 13% higher WEY than PBB and PNB + R plots. Similarly, mean (of the last two years) water productivity of the system in the PBB + R treated plots (12.58 kg wheat grain ha−1 mm−1) was 48, 22, 12, 15, 13, 24% higher compared with CT, PNB, PNB + R, PBB, ZT + R and ZT plots, respectively. The above-said PBB + R plots also had the highest net returns (based on mean values of last two years) that was 36 and 13% higher compared with CT and PNB plots, but was similar to other treatments. Therefore, growing cotton–wheat system under permanent beds with residue retention is recommended under irrigated conditions in this region due to its potential of increased productivity, profitability and resource conservation.
    Field Crops Research 03/2014; 158:24–33. DOI:10.1016/j.fcr.2013.12.017 · 2.61 Impact Factor
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    ABSTRACT: Mixing ratio of ambient ammonia (NH3) was measured at various locations of the National Capital Region (NCR) of Delhi, India using a NH3-analyzer during January 2010 to June 2012 in campaign mode. The present study has been carried out on campaign based measurement of mixing ratios of NH3 and NO x for short period of time over the NCR of Delhi represent the indicative values over the region. The average mixing ratio of ambient NH3 was 20.9 ± 1.6 ppb during the period. The maximum average mixing ratio of ambient NH3 (28.8 ± 3.0 ppb) was recorded in an industrial area surrounded by intensive vehicular traffic followed by an agricultural farm (27.5 ± 2.1 ppb), whereas the minimum (6.4 ± 1.2 ppb) was recorded in the semi-urban area. The diurnal trend of NH3 depended on the ambient temperature at most of the sites and was affected by wind direction. Ambient NH3 was correlated with the NO x mixing ratio suggesting that the vehicular emission may be one of the sources of ambient NH3 in the NCR of Delhi. However, long-term measurements of ambient NH3 and their precursors will lead to seasonal variation of source apportionment over the NCR, Delhi, India.
    MAPAN-Journal of Metrology Society of India 02/2014; DOI:10.1007/s12647-014-0098-9 · 0.48 Impact Factor
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    ABSTRACT: Direct dry-seeding of rice could be a potential option for reducing methane emission. Methane and nitrous oxide emissions were estimated from conventionally transplanted puddled rice (TPR) and direct seeded rice (DSR) using close chamber technique. DSR reduced methane emission drastically as compared to TPR, whereas the emissions of nitrous oxide were marginally higher under DSR. Brown manuring with daincha increased the nitrous oxide emissions from DSR marginally but no significant impact was seen on emissions of methane. The cumulative methane emissions were 1.49 kg ha -1 in DSR and 30.72 kg ha -1 in TPR whereas the nitrous oxide emissions varied from 670 g N 2 O ha -1 in TPR to 1008 g N 2 O ha -1 in DSR. DSR and DSR with brown manuring reduced the global warming potential (GWP) of soil in rice by 70% and 43% respectively over TPR and increased the carbon efficiency ratio.
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    ABSTRACT: Sequestration of C in arable soils has been considered as a potential mechanism to mitigate the elevated levels of atmospheric greenhouse gases. We evaluated impacts of conservation agriculture on change in total soil organic C (SOC) and relationship between C addition and storage in a sandy loam soil of the Indo-Gangetic Plains. Cotton (Gossypium hirsutum L.) and wheat (Triticum aestivum L.) crops were grown during the first three years (2008–2011) and in the last year, maize (Zea mays L.), wheat and green gram (Vigna radiate L.) were cultivated. Results indicate the plots under zero tillage with bed planting (ZT-B) and zero tillage with flat planting (ZT-F) had nearly 28 and 26% higher total SOC stock compared with conventional tillage and bed planting (CT-B) (∼5.5 Mg ha−1) in the 0–5 cm soil layer. Plots under ZT-B and ZT-F contained higher total SOC stocks in the 0–5 and 5–15 cm soil layers than CT-B plots. Although there were significant variations in total SOC stocks in the surface layers, SOC stocks were similar under all treatments in the 0–30 cm soil layer. Residue management had no impact on SOC stocks in all layers, despite plots under cotton/maize + wheat residue (C/M+ W RES) contained ∼13% higher total SOC concentration than no residue treated plots (N RES; ∼7.6 g kg−1) in the 0–5 cm layer. Hence, tillage and residue management interaction effects were not significant. Although CT-B and ZT-F had similar maize aboveground biomass yields, CT-F treated plots yielded 16% less maize biomass than CT-B plots. However, both wheat and green gram (2012) yields were not affected by tillage. Plots under C/M + W RES had ∼17, 13, 13 and 32% higher mean cotton, maize, wheat and green gram aboveground biomass yields than N RES plots, yielding ∼16% higher estimated root (and rhizodeposition) C input in the 0–30 cm soil layer than N RES plots. About 9.3% of the gross C input contributed towards the increase in SOC content under the residue treated plots. However, ∼7.6 and 10.2% of the gross C input contributed towards the increase in SOC content under CT and ZT, respectively. Thus, both ZT and partial or full residue retention is recommended for higher soil C retention and sustained crop productivity.
    European Journal of Agronomy 11/2013; 51:34–42. DOI:10.1016/j.eja.2013.07.003 · 2.92 Impact Factor
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    ABSTRACT: System of rice intensification (SRI) is an alternate method of conventional puddled, transplanted, and continuously flooded rice cultivation for higher yield, water saving, and increased farmer's income. The SRI may also have considerable impact on greenhouse gas emission because of difference in planting, water and nutrient management practices. A field experiment was conducted with three planting methods: conventional puddled transplanted rice (TPR), conventional SRI with 12-days-old seedling (SRI) and modified SRI with 18-days-old seedling (MSRI) to study their effect on methane and nitrous oxide emission. Seasonal integrated flux (SIF) for methane was highest in the conventional method (22.59 kg ha(-1)) and lowest in MSRI (8.16 kg ha(-1)). Methane emissions with SRI and MSRI decreased by 61.1 and 64 %, respectively, compared to the TPR method. Cumulative N2O-N emission was 0.69, 0.90, and 0.89 kg ha(-1) from the TPR, SRI, and MSRI planting methods, respectively. An average of 22.5 % increase in N2O-N emission over the TPR method was observed in the SRI and MSRI methods. The global warming potential (GWP), however, reduced by 28 % in SRI and 30 % in MSRI over the TPR method. A 36 % of water saving was observed with both SRI and MSRI methods. Grain yield in the SRI and MSRI methods decreased by 4.42 and 2.2 %, respectively, compared to the TPR method. Carbon efficiency ratio was highest in the MSRI and lowest in the TPR method. This study revealed that the SRI and MSRI methods were effective in reducing GWP and saving water without yield penalty in rice.
    Paddy and Water Environment 07/2013; 12(3). DOI:10.1007/s10333-013-0390-2 · 1.25 Impact Factor

Publication Stats

2k Citations
190.32 Total Impact Points

Institutions

  • 1999–2015
    • Indian Agricultural Research Institute
      • • Division of Biochemistry
      • • Centre for Environment Science and Climate Resilient Agriculture CESCRA
      • • Division of Agricultural Physics
      • • Nuclear Research Laboratory
      New Dilli, NCT, India
  • 2013
    • Indian Council of Agricultural Research
      New Dilli, NCT, India
  • 2007–2012
    • Central Rice Research Institute
      Каттаке, Odisha, India
    • Cornell University
      • Department of Crop and Soil Sciences
      Итак, New York, United States
  • 2001–2009
    • International Rice Research Institute
      Лос-Баньос, Calabarzon, Philippines
  • 2006
    • University of New Hampshire
      • Institute for the Study of Earth, Oceans, and Space
      Дарем, New Hampshire, United States