化学诱变剂EMS和MNU对燕麦种子萌发和幼苗生长的影响

Effects of chemical mutagens EMS and MNU on seed germination and seedling growth of oat

摘要:

用甲基磺酸乙酯(EMS)、N-甲基-N-亚硝基脲(MNU)2种化学诱变剂,分别对3个燕麦品种(爱沃、陇燕4号、贝勒2代)进行不同浓度、不同时间的浸种诱变处理,测定其发芽率、发芽势和相对致死率、幼苗根长、芽长等指标,探究不同化学诱变剂对燕麦种子萌发和幼苗生长的影响,筛选半致死处理,为燕麦化学诱变育种提供基础数据。结果表明:诱变剂处理显著影响了燕麦种子萌发和幼苗生长,其中诱变剂浓度的效应远大于处理时间和品种的效应,EMS和MNU浓度所引起的发芽率的差异平方和分别占总平方和的89.51%和62.76%。随着EMS、MNU浓度的增加,燕麦种子的发芽势、发芽率呈下降趋势,相对致死率显著上升。诱变剂对燕麦幼苗生长表现出低浓度促进、高浓度抑制的效应,低浓度下燕麦根长和芽长显著大于对照,高浓度下则明显降低。燕麦品种对诱变剂的反应不尽相同,爱沃的耐受性最好,贝勒2代对诱变剂处理最敏感。EMS处理下,爱沃的半致死最佳处理组合是0.25%/17 h和0.75%/14 h;陇燕4号的是0.25%/17 h、0.50%/14 h和0.75%/5 h;贝勒2代的分别为0.25%/11 h、0.50%/8 h和0.75%/5 h。MNU处理,爱沃的最佳半致死处理组合为0.30%/8 h,陇麦4号为0.25%/11 h,贝勒2代为0.20%/11 h。

Abstract:

This study investigated the effects of ethyl methyl sulfonic acid (EMS) and N-methyl-N-nitroso urea (MNU) at different concentrations and duration on seed germination potential,germination rate,relative mortality rate,root length and shoot length of seedlings using three oat varieties (Everleaf,Longyan No.4 and Baler 2).The study aimed to provide basic information for oat chemical mutation breeding.The results showed that the mutagen significantly affected seed germination and seedling growth of oat,and the effects of mutagen concentration was much greater than that of treatment duration and variety.The sum of squares of the difference in germination caused by the concentration of EMS and MNU accounted for 89.51% and 62.76% of the total sum of squares,respectively.With the increasing concentration of EMS and MNU,seed germination potential and germination rate decreased,accompanied with a significant increase in relative mortality rate.The growth of oat seedlings was promoted at low mutagen concentration while inhibited at high concentration.The root and shoot length at low concentration were significantly higher than the control,but remarkably decreased at high concentration.Different oat varieties showed different responses to mutagen treatments,with Ever leaf being the most tolerant,and Baler 2 being the most sensitive.Under the EMS treatment,the optimal semi-lethal treatment was at 0.25% for 17 h and at 0.75% for 14 h for Everleaf;it was at 0.25% for 17 h,at 0.50% for 14 h and at 0.75% for 5h for Longyan No.4;and at 0.25% for 11 h,at 0.50% for 8 h and at 0.75% for 5 h for Baler 2.Under the MNU treatment,the optimal semi-lethal treatment for Everleaf,Longyan No.4 and Baler 2 was at 0.30% for 8 h,at 0.25% for 11 h and at 0.20% for 11 h,respectively.