GROWTH AND YIELD DYNAMICS OF Brassica campestris L. var. toria IN INTERCROPPING WITH OIL SEED BRASSICAS

摘要

A field experiment was conducted with sole crops of toria (Brassica campestris L. var. toria cv Sangam), Indian mustard (Brassica juncea L. Czern & Coss cv RH 30), Ethiopian mustard (Brassica carinata L. Braun cv BC 2) and Swede rape (Brassica napus L. cv Midas) and intercropping of Indian mustard, Ethiopian mustard and Swede rape with toria in 1:1, 2:2 and 1:3 row ratios. The growth parameters (height, dry matter accumulation and leaf area) of toria were improved in intercropping with B. carinata and B. napus and suppressed in intercropping with B. juncea resulting in improvement and suppression up to 14.86 and 6.02 in primary branches, 73.53 and 24.56 in secondary branches. 30.67 and 0.45 in siliquae plant~(-1) and 25.45 and 12.45 per cent in seedyield plant~(-1), respectively compared to sole toria. The increase or decrease in the growth and yield attributes was maximum in 1:1 row arrangement. The seed yield ha~(-1) of toria decreased by 30.62, 36.16 and 45.78 per cent in intercropping with B.carinata, B napus and B. juncea, respectively compared to sole toria because of 50-75 per cent plant population in the former than in the later. The seed yield row~(-1), however, increased by 19.10 and 9.58 per cent in toria + B. carinata and toria + B.napus, respectively and decreased by 6.94 per cent in toria+B. juncea intercrop combinations. The yield attributes and yield of toria was much lower during 1986-87 than 1987-88 due to frost injury at the seed development stage. Toria + B. carinata in 3:1and toria + B. juncea in 1:1 row arrangement were found best in respect of land area utilization (LER) and area and time utilization efficiency (ATER), respectively. Intercropping of B. juncea, B. carinata and B. napus with toria gave an additional netreturns over sole toria in the range of Rs. 1632 to 4051, 792 to 1630 and (-) 298 to 995 ha~(-1), respectively. The net returns in the three intercrop geometries, in general, followed the order of 1:1 > 2:2 > 3:1.