芝麻EMS诱变条件优化与突变体筛选

为明确适于芝麻诱变的最佳甲基磺酸乙酯(EMS)剂量和处理时间,创制优异芝麻突变体,采用0.1%~2.0%EMS浸泡处理芝麻91-0株系种子6~24 h,研究了EMS不同剂量和处理时间对芝麻突变体创制效率的影响。结果显示,0.1%EMS浸种24 h、0.5%EMS浸种24 h、1.0%EMS浸种12 h、1.5%EMS浸种6 h处理芝麻种子发芽势、发芽率为53.13%~90.17%,根长为0.30~2.00 cm,活力指数为18.53~131.00,适于芝麻诱变研究。2008—2010年,选用1.0%EMS浸种12 h优化条件先后处理芝麻91-0株系成熟种子7万粒,共获得M1代植株22 855份,成株率达到32.65%。对诱变株系及其后代叶型、株型、花器与育性、蒴果及粒型以及其他共5类24个田间农艺性状的调查结果表明,M1、M2代诱变率分别为7.60%、2.78%,M1、M2代株系发生的主要突变性状类型均为花器与育性类,比率分别为4.08%、0.93%。对831份突变体后代株系的农艺性状调查结果显示,后代中可稳定遗传的突变体比率为23.71%,主要突变类型为蒴果及粒型,占总调查株系的14.80%。研究表明,在1.0%EMS浸泡12 h诱变处理条件下,芝麻91-0株系发生可遗传突变的比率为0.80%。

Optimization of EMS Mutagenesis Condition and Screening of Mutants in Sesame

In order to clarify the effects of EMS concentration and treat duration on sesame mutation efficiency,seeds of sesame line 91-0 were immersed in EMS solution with various concentrations from 0.1％ to 2.0％ for 6-24 h.The results showed that the treatments with 0.1％ EMS for 24 h,0.5％EMS for 24 h,1.0％ EMS for 12 h and 1.5％ EMS for 6 h were appropriate for sesame mutagenesis.Under the above treatment conditions,the seed germination potential and the germination rate ranged from 53.13％ to 90.17％,the root length varied from 0.30 cm to 2.00 cm,the average vigor index varied from 18.53 to 131.00.To obtain abundant mutants,70 000 seeds of line 91-0 were treated under the optimal condition of 1.0％ EMS for 12 h during 2008-2010.As a result,22 855 mutated lines were harvested with the plant generation ratio of 32.65％.During the mutagenesis investigation,24 agronomic traits related to five groups of traits,i.e.leaf type,plant type,flower and fertility,capsule and seed characters and other physical traits for sesame were applied.Investigation results indicated that the mutation frequencies in M1 and M2 generation were 7.60％ and 2.78％,respectively.For M1 and M2 populations,flower and fertility were the top mutation trait type with the high ratios of 4.08％ and 0.93％,respectively.Further observation of 831 mutants randomly selected from the EMS mutant library reflected that 23.71％ mutants stably descented the mutation traits in the progenies.The top mutated trait of the mutation type was capsule and seed characters,occupying for 14.80％ of the total investigated lines.Morphological variation results predicted that the mutation frequency of line 91-0 reached 0.80％ under 1.0％ EMS for 12 h induction condition.