‘巴西蕉’离体芽的化学诱变和抗镰刀菌酸材料的筛选

CHEMICAL MUTATION AND SCREENING FOR TOLERANCE TO FUSARIC ACID ON SHOOT TIP OF Musa AAA Cavendish cv.'Baxijiao'

在离体条件下,以我国主栽香蕉品种‘巴西蕉’(Musa AAA Cavendish)的多芽体和不定芽为材料,采用EMS和NaN3对其进行诱变处理,以镰刀菌酸毒素为选择压,筛选抗镰刀菌酸的材料。结果表明,EMS和NaN3诱变处理多芽体适宜的浓度和时间组合分别为1.6%+3h和2g/L+3h,NaN3诱变处理不定芽适宜的浓度和时间组合为2g/L+1h。镰刀菌酸毒素筛选多芽体和不定芽适宜浓度范围分别为36～45mg/L和10～20mg/L,筛选获得的多芽体和不定芽多次继代培养后仍保持对镰刀菌酸的抗性。本研究可为香蕉抗枯萎病育种提供有价值的材料和技术参考。

Fusarium wilt is a devastating disease for banana planting. This work was initiated to develop an in vitro technique suitable for mutation induction on ＇ Baxijiao＇ （Musa AAA Cavendish） using chemical mutagens. The experiment was to established the optimal dose of chemical mutagenesis for mutagenic induction of the banana cv. ＇Baxijiao＇ for subsequent mutation breeding. Scalps and shoot apices of in vitro-grown cultures of banana cv. ＇Baxijiao＇ were treated with various concentrations of the mutagens ethylmethanesulfonate （EMS）, sodium azide （ NaN3 ） and fusaric acid to evaluate their effectiveness in inducing mutations and to select variants tolerant to the fungus Fusarium oxysporum f. sp. cubense. The results showed that the optimal concentration and treatments period of EMS and NaN3 on the scalps was 1.6% ＋ 3h and 2g/L ＋ 3h, respectively, but on the shoot apices from adventitious buds, the optimal concentration and treatments period of NaN3 was 2g/L ＋ 1 h. The suitable concentration range of fusaric acid on the scalps and adventitious buds was 36 - g5mg/L and 10 -20mg/L, respectively, for mutation screening. The selected scalps and adventitious buds still kept resistance to fusaric acid after subcultures. However, further identification test is needed for a definitive and reliable result. This study provides a valuable data for the breeding of banana resistance to fusarium wilt.