P. Pathak
International Crops Research Institute for the Semi-Arid Tropics
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Publication
Featured researches published by P. Pathak.
Agricultural Systems | 2000
G. Alagarswamy; Piyush Singh; Gerrit Hoogenboom; Suhas P. Wani; P. Pathak; S.M. Virmani
Crop simulation models are valuable research tools in agricultural decision making. In order to increase its general applicability, models need to be evaluated in diverse conditions. To achieve this, CROPGRO-Soybean model was evaluated on Vertic Inceptisols in a climatically variable semi-arid tropical condition. The model predicted reasonably the temporal changes in leaf area index, biomass and grain yield. The model was used to develop yield–evapotranspiration (ET) relationship, and to assess the influence of soil water-storage capacity on yield. Yield was linearly related to ET and was reduced non-linearly as soil depth decreased. The yield reduction was minimal when depth decreased from 90 to 67 cm but severe reduction occurred when depth decreased below 45 cm. There exists a threshold soil depth (37 cm), below which crop productivity in Vertic Inceptisols cannot be sustained, even in good rainfall years. There is an urgent need to develop sustainable natural resource management technology to prevent further degradation of Vertic Inceptisol. CROPGRO-Soybean model can be successfully used as a research tool to evaluate the risks associated in adapting such technologies.
Field Crops Research | 1999
Piara Singh; G. Alagarswamy; P. Pathak; Suhas P. Wani; Gerrit Hoogenboom; S.M. Virmani
During 1995-1997 a field study was conducted at the ICRISAT Centre, Patancheru, Andhra Pradesh, India, on a Vertic Inceptisol watershed to study the effect of two soil depths, shallow (<50 cm soil depth) and medium-deep (=50 cm soil depth), and two landform treatments, flat and broadbed-and-furrow (BBF) systems, on productivity and resource-use efficiency of a soyabeans-chickpeas rotation. Soyabeans grown on flat landform on medium-deep soil had a higher leaf area index and more light interception compared with the soyabeans grown on the BBF landform. This resulted in an increase in mean seed yield for the flat landform (2.12 t/ha) compared with the BBF landform (1.87 t/ha). However, the landform treatments on shallow soil did not affect soyabean yields. The soyabean yield was higher on the medium-deep soil (1.76 t/ha) than on the shallow soil (1.55 t/ha) during 1995-1996, but were not different during 1996-1997. In both years chickpea yields and total system productivity (soyabean + chickpea yields) were greater on medium-deep soil than on the shallow soil. Total run-off was higher on the flat landform (25% of seasonal rainfall) than on the BBF landform (20% of seasonal rainfall). This concomitantly increased profile water content (10-30 mm) of both soils in BBF compared with the flat landform treatment during 1995-1996, but not during 1996-1997. Deep drainage was higher in the BBF landform than in flat, especially for the shallow soil. Across landforms and soil depths, water use (evapotranspiration) by soyabeans-chickpeas rotation during 1996-1997 ranged from 496 to 563 mm, which accounted for 54-61% of the rainfall. These results indicate that while the BBF system is useful in decreasing run-off and increasing infiltration of rainfall on Vertic Inceptisols, there is a need to increase light use by soyabeans on BBF during the rainy season to increase its productivity. A watershed-based farming system needs to be adopted to capture significant amount of rain water lost as run-off and deep drainage. The stored water can be used for supplemental irrigation to increase productivity of soyabean-based systems leading to overall increases in resource-use efficiency, crop productivity and sustainability.
Field Crops Research | 1999
Piara Singh; G. Alagarswamy; Gerrit Hoogenboom; P. Pathak; Suhas P. Wani; S.M. Virmani
A field study was conducted on a Vertic Inceptisol during 1995-1997 seasons at the ICRISAT Centre, Patancheru, India, to study the effect of two landforms (broadbed-and-furrow (BBF) and flat) and two soil depths (shallow and medium-deep) on crop yield and water balance of a soyabean-chickpea rotation. Using two seasons experimental data, a soyabean-chickpea sequencing model was evaluated and used to extrapolate the results over 22 years of historical weather records. The simulation results showed that in 70% of years total runoff for BBF was >35 mm (range 35-190 mm) compared with >60 mm (range 60-260 mm) for flat on the shallow soil. In contrast on the medium-deep soil it was >70 mm (range 70-280 mm) for BBF compared with >80 mm (range 80-320 mm) for the flat landform. The decrease in runoff on BBF resulted in a concomitant increase in deep drainage for both soils. In 70% of years, deep drainage was >60 mm (range 60-390 mm) for the shallow soil and ranged from 10 to 280 mm for the medium-deep soil. In 70% of years, the simulated soyabean yields were >2.2 t/ha (range 2.2-3.0 t/ha) and were not influenced by landform or soil depth. In the low rainfall years, yields were marginally higher for the BBF than for the flat landform, especially on the shallow soil. Simulated chickpea yields were higher for the medium-deep soil than for the shallow soil. In most years, marginally higher chickpea yields were simulated for the BBF than for the flat landform on both soil types. In 70% of years, the chickpea yields were >0.5 t/ha (range 0.5-1.5 t/ha) for the shallow soil, and >0.8 t/ha (range 0.8-1.96 t/ha) for the medium-deep soil. Total productivity of a soyabean-chickpea rotation was >3.0 t/ha (range 3.0-4.15 t/ha) for the shallow soil and >3.45 t/ha (range 3.45-4.7 t/ha) for the medium-deep soil in 70% of years. These results showed that in most years BBF increased rainfall infiltration into the soil and had marginal effect on yields of soyabeans and chickpeas. Crop yields on Vertic Inceptisols can be further increased and sustained by adopting appropriate rain water management practices for exploiting surface runoff and deep drainage water as supplemental irrigation to crops in a watershed setting.
Journal of Crop Improvement | 2009
Piara Singh; P. Pathak; Suhas P. Wani; K. L. Sahrawat
Poverty, food insecurity, and malnutrition are pervasive in the semi-arid tropics (SAT) of South Asia, including India. In rural areas, most of the poor make their livelihoods on the use of natural resources, which are degraded and inefficiently used. This is because of the inadequate traditional management practices of managing agriculture as well as the fact that resulting crop yields are much below the expected potential yields. ICRISAT in the early 1970s initiated research on watersheds for integrated use of land, water, and crop management technologies for increasing crop production through efficient use of natural resources, especially rainfall that is highly variable in the SAT and is the main cause of year-to-year variation in crop production in India. Improved watershed management on Vertisols more than doubled crop productivity, and rainfall-use efficiency increased from 35% to 70% when compared with traditional technology. After many years of implementing and evaluating these improved technologies in on-farm situations, many lessons were learned and they formed part of the integrated watershed management model currently being pursued by ICRISAT in community watersheds in rural settings. This watershed model is more holistic and puts rural communities and their collective actions at center stage for implementing improved watershed technologies with technical backstopping and convergence by consortium partners. We describe here the achievements made in enhancing crop productivity and rainfall-use efficiency by implementing improved technologies in on-farm community watersheds in India.
Agricultural Water Management | 1991
P. Pathak
Abstract Development and testing of a simple runoff sampler which can be used to monitor the quantity of sediment carried by runoff from small agricultural watersheds is presented. The sampler uses the rapidly fluctuating flow nature to account for the temporal variation in sediment concentration. Intensive laboratory testing was carried out for sampler efficiencies at various flow and sediment conditions. Overall efficiency obtained was in the range of 87 to 98%. The sediment catching efficiencies for clay, silt, fine sand and coarse sand particles were 96%, 87%, 75% and 60%, respectively. The sampler has been in use for the last 4 years in the field and its general performance has been satisfactory.
Agricultural Water Management | 1989
P. Pathak; K.B. Laryea; Sardar Singh
Abstract Contour bunding is the most widely practised soil conservation measure on Alfisols of the semiarid tropics in India. The conventional contour bund system allows water to stagnate for long periods in extensive areas along the bunds that affects crop yields in these areas. Crop yields from sorghum/pigeon pea intercrop and pearl millet/pigeon pea intercrop at different distances from the bunds were measured to demonstrate the effects of bunding. The effects of eroded sediment deposition on the infiltration behavior of the zone near the bunds are also discussed. A modified contour bunding system with gated outlets is described. Contour bunds with gated outlets were found to ensure adequate control of runoff and soil loss. Crops grown in the fields bunded by gated outlets yielded better than those grown in fields surrounded by conventional bunds. The water balance of the ponded areas near the bunds is presented for both the modified and conventional contour bunding systems.
Soil Use and Management | 2003
Suhas P. Wani; P. Pathak; L.S. Jangawad; H. Eswaran; Piara Singh
Archive | 2002
P. Pathak; Suhas P. Wani; R Sudi; Ch Srinivasa Rao
Measuring soil processes in agricultural research | 1997
Piara Singh; K. P. R. Vittal; K. B. Laryea; P. Pathak; J. C. Katyal
Agricultural Water Management | 2013
P. Pathak; R Sudi; Suhas P. Wani; K. L. Sahrawat
Collaboration
Dive into the P. Pathak's collaboration.
International Crops Research Institute for the Semi-Arid Tropics
View shared research outputsInternational Crops Research Institute for the Semi-Arid Tropics
View shared research outputsInternational Crops Research Institute for the Semi-Arid Tropics
View shared research outputsInternational Crops Research Institute for the Semi-Arid Tropics
View shared research outputsInternational Crops Research Institute for the Semi-Arid Tropics
View shared research outputsInternational Crops Research Institute for the Semi-Arid Tropics
View shared research outputsInternational Crops Research Institute for the Semi-Arid Tropics
View shared research outputsInternational Crops Research Institute for the Semi-Arid Tropics
View shared research outputs