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

摘要

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 2012-13, to study the effect of soil-moisture conservation (SMC) measures on nutrient uptake and soil fertility in maize (Zea mays L.)-based cropping sequences. Significantly the highest soil organic carbon (SOC) was recorded under maize-French bean (Phaseolus vulgaris L.) (pole type) system (1.72%) followed by maize-blackgram [Vigna mungo (L.) Hepper] (1.70%) at 0-15 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 artemlsiifolia 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 maize-French bean cropping system. The MSM + Tephrosia mulch recorded significantly higher soil available N, P and K, followed by MSM + Ambrosia. Maize-French bean (pole type) cropping system had significantly higher soil microbial biomass carbon (SMBC; 258.55 ug/g soil) and dehydrogenase activity (DHA; 37.27 ug TPF/hr/g) than that under maize-fallow.Among the SMC measures, MSM + Tephrosia recorded the maximum SMBC (265.75 ug/g soil) and DHA (34.27 ug TPF/hr/g) followed by MSM + Ambrosia. 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 obtained from maize-Frenchbean (pole type) system under MSM + Tephrosia mulch (9.5 t/ha), followed by MSM + Ambrosia mulch (8.8 t/ha).