Soybean-chickpea rotation on Vertic Inceptisols I. Effect of soil depth and landform on light interception, water balance and crop yields uri icon

abstract

  • 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

publication date

  • 1999
  • 1999