Root development, water use and water-use efficiency of sorghum (Sorghum hicolor) as influenced by vegetative barriers in alley cropping system under rainfed condition

Root development, water use and water-use efficiency of 3 sorghum [Sorghum bicolor(L.) Moench] varieties, viz. ‘CSV 13’, ‘CSV 15’ and ‘Varsha’, raised in alleys formed by different vegetative barriers, viz. Sesbania sesban, Leucaena leucocephala, Cajanus cajan, Vetiveria zizanoides and Cenchrus ciliaris, and unbarriered (control) were studied during the rainy seasons of 1995 and 1996 at Kanpur on light-textured alluvial soil. Best root development of sorghum was observed when raised in alleys of Sesbania, followed by Leucaena, while the poorest root development in alleys of Cenchrus ciliaris. Among the sorghum varieties ‘Varsha’ resulted in better root development in terms of depth, breadth, number and weight than ‘CSV 13’ and ‘CSV 15’. Better root development of sorghum ‘Varsha’ raised in alleys of Sesbania resulted in higher water use and water-use efficiency and yield attributes like 1, 000-grain weight, grains/panicle, grain and fodder yields where ‘Varsha’ excelled ‘CSV 13’ and ‘CSV 15’. Total water use of sorghum under Sesbania was 388.5 mm which was 9.5 mm higher than the control (unbarriered) crop. The water-use efficiency of sorghum in association with Sesbania was 5.3 kg/ha-mm as compared with 4.1 kg/ha-mm unbarriered (control).