桑树多倍体及其育种研究进展

列举了天然多倍体桑的种类,我国是桑多倍体资源最丰富的国家,迄今发现的有3倍体、4倍体、6倍体、8倍体和22倍体,还有天然单倍体。阐述了多倍体桑的性状,其中以3倍体的经济性状较好。总结了人工诱导4倍体的方法,其中以0.2％为中心浓度的秋水仙碱注射膨芽、生长点和处理子叶展开期的实生苗较有效。说明了4倍体、2倍体间杂交和诱导二倍化性配子培育三倍体的技术问题。展望了今后桑的多倍体育种前景。

PROGRESS IN POLYPLOIDY STUDY AND POLYPLOID BREEDING OF MULBERRY

On the basis of data collected by the authors, China has the most abundant mulberry poly- ploid resources,of Which natural triploid,tetraploid,hexaploid,octoploid,docosaploid and spontaneous haploid as well have been discovered. Triploid possesses, generally, the best economic characteristics among various mulberry ploids. The most efficient method for inducing artificial te-traploids is ,probably,to inject approximate 0. 2% colchicine solution into mulberry's swelling bud, growing point or apply the solution to the seedling of which cotyledons are expanding. The paper also deals with the technical problems in breeding triploid by crossing between tetraploid and diploid and by diploidizing gametes,and the prospects for mulberry pplyploid breeding in the future.