利用花粉化学诱变快速创造特用玉米新种质

The Quick Development of Speciality Corn by Chemical Mutagenesis of Pollen

采用含有化学诱变剂EMS的石蜡油,直接处理玉米自交系黄早4和7922的成熟花粉,并结合M_2代突变基因的等位性测验,对花粉化学诱变创造特用玉米进行了研究.结果表明,在不同EMS处理浓度下,白色胚乳基因yl的诱变率平均为35.22%.,最高达到150.38%.1.67×10^(-3)可作为EMS诱发yl基因突变的参考浓度.糖胚乳基因sul、糯胚乳基因wxl、脆胚乳基因btl和直链淀粉扩充基因ael的单基因诱突率分别为2.54×10^(-3)、l.09×10^(-3)、0.36×10^(-3)和 0.36×10^(-3).sul和wxl的诱变率至少是自然突变率的100～1000倍.由于发生的是点突变,得到的为原亲本自交系的等基因突变体,因此该技术在育种实践和基础研究中具有重要意义.

The quick development of speciality corn was carried out by direct treating mature pollen of corn inbred Huangzao 4 and 7922 with ethyl methanesulfonate in paraffin oil. Allele tests of M2 mutated genes were made with the existed speciality corn kernel genes. The results showed that the induced mutation rate of y1 gene was 35. 22‰ on average, and the highest was 150. 38‰, under the different EMS treatment levels. 1. 67×10-3 treatment level was recommended for inducing y1 gene mutants. The mutation frequencies of sugary gene sul, waxy gene wx1, brittle gene bt1 and amylose extender gene ae1 were 2.54×10-3, 1. 09×10-3, 0. 36×10-3 and 0. 36×10-3, respectively. The induced mutation frequencies of su1 and wx1 were 100～1000 times over the spontaneous ones. The mutants were isogenic lines of original inbred, because of point mutation. Thus, the paraffin oil technique has a great potential in breeding practices and biological research.