Effect of alley cropping of castor (Ricinus communis) and integrated nutrient management practices on productivity status of soil under SAT regions

Abstract

A study was conducted during 1996 and 1997 to find out the changes in productivity status of soil due to alley cropping of castor (Ricinus communis L.) and integrated nutrient management practices at Hyderabad. Physical properties of soil like field capacity (18.1 and 19.9%) and infiltration rate (7 and 7.2 cm/hr) improved, while the bulk density (1.49 and 1.29 mg/m 3) decreased due to alley cropping in both the years over sole cropping of castor. Application of green leaf manures of trees also increased the field capacity and infiltration rate and reduced the soil compaction when compared with no green leaf manuring. Leucaena green leaf manuring produced pronounced effect of increasing field capacity (18.9 and 21.2%) and infiltration rate of the soil (7.5 and 8.6 cm/hr) but reduced the bulk density (1.48 and 1.24 mg/m3) specially under alley cropping with Dalbergia. Field analysis of soil samples seasonally for chemical properties indicated that available N, organic carbon, total nitrogen and C:N ratio were found optimum under alley cropping with green leaf manuring 90 days after sowing (DAS) with gradual increase from 30 DAS. Incubation studies at different periods also showed that the soil fertility started building up from initial stages of incubation both under alley cropping and green leaf manuring. However, the soil productivity in terms of available nitrogen, organic carbon, total nitrogen and C:N ratio was found better at 75 days after incubation (DAI) in alley cropping and green leaf manuring as well.