Multiple cropping in rainfed upland entisol under different soil management conditions in the sub-humid tropics

Abstract

Field experiments were conducted for 2 years on a well drained upland sandy loam soil under rainfed conditions to study the effects of previous summer season crops of jute ( Corchorus olitorius L.) and direct seeded rice ( Oryza sativa L.) in unpuddled and unbunded soil followed by a short duration legume crop (rice bean ( Vigna umbellata (Thunb.) Ohwi and Ohashi) for forage or greengram ( Vigna radiata (L.) Wilczek) for grains) and fallow on the (i) productivity winter crops of barley ( Hordeum vulgare L.), lentil ( Lens esculenta Moench), field peas ( Pisum sativum L.), linseed ( Linum usitatissimum L.), mustard ( Brassica juncea (L.) Czern & Coss) and sunflower ( Helianthus annuus L.), (ii) soil profile moisture storage and (iii) its utilization. The winter crops were established with minimum (making sowing slots of 5 cm depth with a hand-drawn seed drill and without maintenance of mulch over surface) and conventional (four ploughings up to 15 cm depth with bullock drawn plough) methods of land preparation. The results revealed that compared to jute/fallow and jute/legume sequences, rice/fallow and rice/legume sequences resulted in higher soil moisture storage and, hence, a greater degree of seedling emergence per unit area, higher root weight and water use, and consequent higher grain yields and water use efficiency (WUE) of the subsequent winter crops. Winter crops yielded 17% more following direct seeded rice than after jute. Growing of short duration legume (rice bean or greengram) after jute or rice depleted stored moisture but increased yield and WUE of all winter crops. Grain yields of winter crops were 19% higher in tilled than in untilled soils. Under conventional tillage the soil moisture was slightly reduced at the time of sowing of winter crops but it resulted in increments in root weight, water use, grain yields and WUE of winter crops. WUE of barley was highest followed by field peas, which utilized more of soil moisture conserved at lower soil depths than other crops. Mustard gave the highest return (Rs.4663) followed by field peas (Rs.4603).