Direct and residual effect of Zn application in groundnut-wheat cropping system in Alfisols

摘要

A field experiment was conducted during 1999-2001 to study the effect of zinc on pod yield and Zn uptake in groundnut (Arachis hypogaea L.) and their residual effect on succeeding wheat (Triticum aestivum L.) using 6 soils of old alluvial plains of Tonk district of Rajasthan. Application of Zn @ 2.5 and 5.0 kg/ha produced 16.0 and 21.2% higher pod yield in groundnut crop over control. Among the soils, maximum pod yield of groundnut was recorded in sandy loam soil (1553 kg/ha) followed by loamy sand (1469 kg/ha) and sandy soil (1427 kg/ha). Zn-uptake by pods increased significantly with increasing levels of zinc and maximum value (96.7 g/ha) was recorded with application of 5.0 kg Zn/ha. Residual effect of zinc @ 2.5 and 5.0 kg/ha application increased the grain yield of wheat by 7.1 and 15.4%, respectively over control. Similar trend was found in straw yield of wheat. In the case of residual effect of Zn within soil texture, maximum grain yield was obtained in sandy loam (4520 kg/ha) followed by loamy sand (4356 kg/ha) and sandy soil (3622 kg/ha). Residual effect of Zn also increased the Zn uptake by grain and straw of wheat significantly over control. The highest Zn uptake values 112.4 g/ha by grain and 93.5 g/ha straw was obtained at their residual effect of 5.0 kg/ha application. The higher yields of groundnut-wheat are possible in Zn deficient alfisols by using 5.0 kg Zn/ha/year in groundnut crop.