4x-2x杂交创制马铃薯新种质

Creation of New Potato Germplasms by 4x-2x Cross

以二倍体马铃薯‘USW4’和Solanum chacoense杂交产生的F1株系‘XD-3’为材料,检测其2n花粉产率和花粉活力。研究结果表明,‘XD-3’能产生2n花粉,2n花粉产率约7.7%,且花粉活力较高,达74.75%。在此基础上,开展了4x-2x杂交,进行了4个不同的杂交组合,平均杂交结实率为36.5%,但平均种子数/浆果仅0.67粒。4个不同的杂交组合共获得19个杂交后代,2对父本特异的SSR引物检测结果表明,有14个株系可以确认为真杂种;杂种植株的倍性检测结果表明,7个为三倍体,7个为四倍体。大量三倍体的产生为n花粉的直接利用提供了一条新思路。

Diploi＇;XD-3＇ a F1 progeny from a cross of Solanum chacoense and cultivated diploid ＇USW4＇, was crossed to four tetraploid potato varieties （2n=4x ） as male parent. The results showed that diploid ＇XD-3＇ produced 7.7%2n gamete and pol en viability was 74.75%. However, the total pol ination efficiency was low and the average successful pol ination percentage over four different cross combinations was 36.5%, and the average seed number per berry was 0.67. The identification results of the progenies showed that 14 out of 19 were hybrids which exhibited SSR specific bands of ＇XD-3＇. The analysis of the ploidy showed that seven hybrids were triploid and seven were tetraploid. The triploid might provide a new approach to make use n pol en of wild species directly.