不同生态条件下玉米单倍体自然加倍率及除草剂加倍效果

单倍体加倍率低成为玉米单倍体育种的限制性因素。为了提高玉米单倍体的加倍率,研究两种生态条件下单倍体的自然加倍率,比较甲基胺草磷(APM)和氟乐灵两种除草剂在不同浓度和处理方法下玉米单倍体的加倍效率。结果表明,海南试验点的单倍体自然加倍率要高于贵州贵阳试点。应用除草剂可以明显提高雅玉889和京糯208单倍体的加倍率,基础材料基因型对自然加倍率和除草剂加倍率都具有显著影响。APM和氟乐灵均是在浓度为80μmol·L~(-1)处理单倍体加倍率最高,APM处理的单倍体加倍率要高于氟乐灵,采用滴心法和浸种法处理的单倍体加倍率无明显差异。综上,如采用自然加倍,应在海南试验点种植单倍体;如采用除草剂加倍,应使用浓度为80μmol·L~(-1)的APM,采用滴心法或浸种法对雅玉889和京糯208单倍体加倍。

Effects of the ecological condition and herbicide on chromosome doubling of haploid maize

A low chromosome doubling rate of haploids becomes the limiting factor in maize haploid breeding at present.The purpose of this experiment was to improve the doubling rate of maize haploid in two ecological systems and through the herbicide application.Two herbicides,amiprophos-methyl (APM) and trifluralin at different concentrations with different methods were tested.The 2-year experimental result showed that the natural doubling rate of maize haploids grown in Jiusuo,Hainan Province was much higher than that in Guiyang,Guizhou Province.The doubling rates of haploid Yayu889 and Jingnuo208 were significantly improved with the application of herbicides.The doubling rate was also significantly affected by the haploid genotype.The doubling rate was the highest when APM and trifluralin at 80 μmol/L were applied with the rate of APM treatment being higher than that of trifluralin treatment at the same concentration.There is no obvious difference in the doubling rate between the soaking seed method and the dripping interior leaf whorls from the 3-leaf stage method with the same herbicide.If the natural doubling method was adopted,the haploid of maize should be planted in Jiusuo,Hainan;if herbicide application was adopted,APM at 80 μmol/L should be chosen using the method of dripping interior leaf whorls or seed-soaking for doubling Yayu889 and Jingnuo208 haploids.