The effect of ethyl methane sulphomate (EMS) and sodium azide (NaN sub 3 /sub ) on plant regeneration capacity of an embryogenic cell suspension of 'Yueyoukang 1' ( Musa , AAA), a banana cultivar resistant to Fusarium wilt.

摘要

The best approach to control Fusarium wilt of banana (Musa spp.) is to grow resistant cultivars. 'Yueyoukang 1' (AAA, Cavendish) is a cultivar highly resistant to Fusarium oxysporum f. sp. cubense race 4, but its yield is lower and its growth cycle longer than other commercial cultivars. In this study, an embryogenic cell suspension (ECS) of this cultivar was mutated with chemical mutagenic agents sodium azide (NaN₃) and ethyl methane sulphomate (EMS). This was followed by plant regeneration via somatic embryogenesis. The aim was to optimise the dosage (concentration and duration) of the agents for obtaining desirable mutants with higher yield potential and shorter growth cycle. The effects of treatment duration of EMS (0.2%, v/v) and the concentration of NaN₃ (treatment duration was 30 min) on the plant regeneration capacity of ECS were investigated. The plant regeneration capacity decreased with an increase in NaN₃ concentration. When the concentration of NaN₃ was 5.42 mmol/L, the plant regeneration capacity of treated ECS was 50% of that obtained in the control (LD₅₀ of NaN₃=5.42 mmol/L). The effect of EMS treatment on the plant regeneration capacity of ECS was also remarkable. When the ECS was treated with 0.2% EMS for 10 minutes, the plant regeneration capacity was even higher than that of the control. But the plant regeneration capacity decreased with increasing treatment duration. The amount of plants obtained per gram of ECS treated with 0.2% of EMS for 18.1 min was 50% of that obtained in the control (LD₅₀ of EMS=18.1 min). The dosages at LD₅₀ are suggested to be used for the generation of mutants with improved yield and growth cycle.