提高小麦×玉米中小麦单倍体苗加倍率的研究

Study on Improving Frequency of Chromosome Doubling in Wheat Haploid Produced by Wheat×Maize System

以小麦玉米杂交产生的小麦单倍体为材料,研究了单倍体苗分蘖节切口预处理对加倍率的影响。结果表明,加倍前对分蘖节进行切口处理的单倍体苗加倍率和加倍效率均达90.3%,比对照高16个百分点。对560个加倍成功的DH株的第一结实穗位分布进行了统计,从主茎开始结实的植株只占31.1%,其余均从分蘖穗开始结实,个别植株到第13个分蘖穗才收到种子;前5个穗位开始结实的植株占82.1%,前7个穗位占94.3%。结果表明,小麦单倍体的加倍率不仅受加倍方法的影响,还与加倍处理前后的栽培技术有关,培育多蘖壮苗、提高分蘖成穗率是提高加倍率的重要保障。

Effects of incising the tillering node of haploid seedling before treated with colchicine on the frequency of chromosome doubling were investigated.Results indicated that the pre-treatment of incising tillering node obviously increased the doubling frequency from 74.3 %（CK） to 90.3 %. According to the analysis of ear order beginning seed-set in 560 doubled haploids,only 31.1 % doubled plants begin seed-set from the main stem,most from the tiller ears,varying from the first to the thirteenth tiller,the total proportion of seeding from the top five ears were 82.1 %,that from the top seven ears were 94.3 %,suggesting that developing as many tillers and tiller ears as possible for haploid through cultivation before and after doubling was the guarantee of getting higher doubling frequency.