Soil properties and nutrient uptake as influenced by mulching in maize (Zea mays)-based cropping systems

Abstract

A field experiment was conducted at the ICAR Research Complex for NEH Region, Umiam, Meghalaya (950 m above sea-level) during the rainy (kharif) and winter (rabi) seasons of 201213, to study the effect of soil-moisture conservation (SMC) measures on nutrient uptake and soil fertility in maize (Zea mays L.)-based cropping se- quences. Significantly the highest soil organic carbon (SOC) was recorded under maizeFrench bean (Phaseolus vulgaris L.) (pole type) system (1.72%) followed by maizeblackgram [Vigna mungo (L.) Hepper] (1.70%) at 015 cm depth. In-situ maize stover mulch (MSM) + white hoarypea (Tephrosia candida DC.) @ 10 t/ha (on fresh weight basis) mulch resulted in significantly higher SOC (1.72%), followed by MSM + ragweed (Ambrosia artemisiifolia L.) mulch 10 t/ha (1.69%). The highest soil available N (268.6 kg/ha) and P (15.7 kg/ha) were recorded under maize blackgram and K (277.6 kg/ha) under maizeFrench bean cropping system. The MSM + Tephrosia mulch re- corded significantly higher soil available N, P and K, followed by MSM + Ambrosia. MaizeFrench bean (pole type) cropping system had significantly higher soil microbial biomass carbon (SMBC; 258.55 ?g/g soil) and dehydroge- nase activity (DHA; 37.27 ?g TPF/hr/g) than that under maizefallow. Among the SMC measures, MSM + Tephrosia recorded the maximum SMBC (265.75 ?g/g soil) and DHA (34.27 ?g TPF/hr/g) followed by MSM + Am- brosia. On an average, nutrient (N, P and K) content and uptake in seed and stover of all the rabi crops were the highest under MSM + Tephrosia followed by MSM + Ambrosia system. The highest maize-equivalent yield was ob- tained from maizeFrenchbean (pole type) system under MSM + Tephrosia mulch (9.5 t/ha), followed by MSM + Ambrosia mulch (8.8 t/ha).