马铃薯种间体细胞杂种的育性和遗传改良

Fertility and Genetic Improvement of Interspecific Somatic Hybrids of Potato

对马铃薯双单倍体品系 81- 15和南美二倍体栽培种 Solanum phureja及二倍体野生种 Solanum chacoense原生质体融合获得的 2 5个株系的花粉育性和雌配子育性进行了测定。结果显示 ,马铃薯种间体细胞杂种花粉育性与其双亲相比明显降低。 81- 15 +S.phureja和 81- 15 +S.chacoense的种间体细胞杂种的花粉育性范围分别为 7.0 %～ 42 .8%和 8.0 %～ 2 0 .1%,花粉中小花粉所占的比例明显增加 ,最高的可达 36 .0 %。对体细胞杂种进行人工辅助自花授粉每个浆果得到的种子数较少 ,但用四倍体栽培品种甘农薯 3号作父本进行授粉时每个浆果得到较多的种子 ,最多的可达每个浆果 38.4粒 ,说明雌配子育性较好。以甘农薯 3号作父本 ,4个优良的体细胞杂种作母本进行 1次杂交和 1次回交 ,从回交后代中选育出了 10个农艺性状优良、块茎性状表现较好、块茎产量高、高淀粉和低还原糖含量的优良株系。这些结果表明 ,体细胞融合技术与常规育种技术相结合 ,是进行马铃薯遗传改良和选育新品系的有效途径。

The pollen viability and female fertility of 25 somatic hybrids obtained by protoplast fusion between a dihaploid of Solanum tuberosum strain 81-15 and two diploid species (a South American diploid cultivated species Solanum phureja and a diploid wild species Solanum chacoense)were investigated. The results indicated that although the fertility of the male gametes of the interspecific somatic hybrid was rather low, as revealed by lower percentages of fertile pollens, higher percentages of small pollens and lower percentages of seedsetting after self-pollination, the fertility of the female gametes was much better. The seedsetting after pollinated with a commercial variety Gannongshu No.3 ranged from 7.5～38.4/fruit, as compared with 0～12.5/fruit, when the somatic hybrids were self-pollinated. Four better lines of the interspecific somatic hybrids were backcrossed sexually with Gannongshu No.3 and ten promising lines whose agronomic traits were better then, at least not inferior to, Gannongshu No.3 were obtained, indicating interspecific somatic hybridization, when combined with traditional breeding method, might be as a new approach for the genetic improvement and the development of new cultivars in potato breeding.