Screening of oilseed Brassica varieties for drought tolerance at the early stages of plant growth

Drought tolerance of ten oilseed Brassica varieties comprising Brassica rapa (4), B. juncea (3), and B. napus (3) were tested in vitro in two separate experiments. In the first experiment seeds of the varieties were germinated on MS medium containing 0.0, 4%, 6%, 8% and 10% PEG-6000. The seedlings were grown up to 15 days. The characters germination percentage, shoot and root length, shoot and root weight both fresh and dry were studied. Highly significant variations among the varieties, drought stress levels and interactions were found for all the characters. The results revealed that impose of osmotic stress caused reduction in germination and adversely affect the seed germination and subsequent seedling growth. On the basis ranking the varieties BINA Sarisha-3, Sampad, BARI Sarisha-7, and Shambal were found to be superior in respect of drought tolerance. In the second experiment hypocotyls of the genotypes were used for callus induction capability under 8% PEG level. In the study it was observed that the varieties BINA Sarisha-3, Sampad, BARI Sarisha-7, and Shambal were more successful in callus induction. From the studies it may be concluded that varieties of B. napus are more drought tolerant than these of B. rapa and B. juncea