Abstract
Two sets of experiments were conducted in the Rabi season (October to March) for consecutive three years beginning from 1999-2000. In the first set, 40 genotypes of B. campestris (10), B. juncea (13) and B. napus (17) were tested for saline tolerance both in pot and field of Kalapara. In the second set, five selected genotypes were tested under different cultural and management practices. The saline tolerance test was conducted in pot culture as well as in the field. The pot culture experiment was conducted at the Regional Agricultural Research Station of Bangladesh Agricultural Research Institute at Rahmatpur, Barisal and the field experiment was conducted at the Multi Location Testing Site of On Farm Research Division of BARI at Kalapara, Patuakhali. In the screening experiments, the genotypes M-27, Dhali and Tori-7 of M-27. B. campestris; M-21-E2-6-1, M-36-E2-7, Daulat and Rai-5 of B. juncea and BINA Sarisha-3, BINA Sarisha-4 and MM-7 of B. napus were found tolerant against salinity. In general, the saline tolerance genotypes showed better performance in root and shoot length, root and shoot fresh and dry weight, crop growth rate, relative growth rate, net assimilation rate, leaf area index and dry matter production than those of the susceptible ones. In respect of sowing time, on an average, the highest seed yield was obtained from 1 November sowing followed by 15 November and the lowest values received in 15 December sowing during both the years. Seed yield declined gradually by 4.77, 43.21 and 57.97%, respectively for each delay by 15 days in sowing after 1 November. Among the genotypes, M-21-E2-6-1 produced the highest seed yield followed by M-27 and the lowest in Tori-7. Investigation on management practices revealed that pre-sowing irrigation + irrigation on 28 DAS with 160 and 100 kg/ha of N and P, respectively produced the highest seed yield followed by irrigation on 28 DAS with 160 and 100 kg/ha of N and P, respectively. It was revealed that pre-sowing irrigation + irrigation on 28 DAS in combination with 200 and 80 kg/ha of N and K, respectively topped the list in terms of seed yield which differed significantly with the rest of the treatments. From the effect of seed rate and fertilizer level on small and bold seeded genotypes the bold seeded Dhali with high fertilizer level and 12 kg/ha seed rate produced the highest seed yield which was identical to that of M-27 with high fertilizer level and 12 kg/ha seed rate. Among 11 management practices cowdung, poultry manure, sloping bed system and mustard oil cake showed better yield and yield. attributes in saline area.