Economic-viability of sequential cropping systems under non-saline calcareous soil of Bihar

Abstract

An experiment was conducted at the CTRI Research Station, Pusa, Bihar, during 1994-95, 1996-97 and 1997-98 on sandy loam (alluvial), non-saline calcareous soil (pH 8.2) under irrigated condition. Treatments con- sisted of 12 tobacco (Nicotiana tabacum L.)-based cropping sequences involving legumes (pulses and oil- seeds), cereals and non-legumes in the system in randomized block design with 4 replications. Total cured leaf yield, first grade outturn (high-value marketable produce) and physical leaf quality parameters in base crop of to- bacco were significantly influenced due to different sequential cropping systems. The maximum total cured leaf yield of 2,384 kglha and first-grade outturn of 1,508 kglha were recorded in sequence of sunnhemp (Crotalaria juncea L.) (GM)-tobacco-fallow (summer ploughing), followed by rice (Gryza sativa L.) -tobacco-cowpea [Vigna unguiculata (L.) Walp.] (2,301 and 1,495 kglha), sunflower (Helianrhils amuus L.)-tobacco-blackgram (Phaseolus mungo L.) (2,236 and 1,425 kglha) and groundnut (Arachis hypogaea L.)-tobacco-greengram (I? radiatus L.) (2,218 and 1,420 kglha) total cured and first-grade leaf yields respectively). The minimum Orobanche (a total root parasite) incidence in base crop tobacco was observed when tobacco was preceded or succeeded by sesame (Sesamum indicum L.). Leaf-area mdex (LAI) and physical leaf quality parameters such as spangling, puckering and maturity In tobacco followed almost s~milar trend to that of tobacco leaf yields. The maximum net return (Rs 65,8321ha) was recorded in sequence sunflower-tobacco-blackgram, followed by groundnut-to- bacco-greengram (Rs 64,893/ha), soybean-tobacco-sunflower (Rs 63,702lha) and blackgram-tobacco-sor- ghum [Sorghum bicolor (L.) Moench] + moth (Rs 63,5051ha) sequences. The minimum net return (Rs 53,523lha) was recorded in maize (Zea mays L.) tobacco-maize.