大豆2个种皮不完整突变体的形态特点与遗传分析

为揭示种皮不完整性遗传规律,发掘关键基因,本试验采用理化诱变剂处理不同大豆品种以创制种皮新突变体,并对其进行形态与遗传特性鉴定,其中从~(60)Co-γ射线辐照的科丰1号M_3株行发现种皮不完整突变体scd-KF,从甲基磺酸乙酯处理的南农1138-2 M_4株行发现突变体scd-NN。scd-KF突变体种皮开裂出现在种子成熟初期,种子背部纵向或横向开裂,程度与种子大小有关;scd-NN突变体种子发育早期种皮即受到影响,种子背部纵向开裂,2片子叶之间有明显裂缝,种子显著小于其野生型。遗传分析结果表明,scd-KF种皮不完整性状由单隐性基因控制,而scd-NN的突变性状在F_2符合15∶1的分离比例,可能由2对隐性基因控制。2个突变体杂交F_2植株的株高及单株荚数、粒数及每荚粒数低于正常种皮植株,但大部分性状未达到显著差异水平。本研究结果为深入揭示大豆种皮及种子发育提供了遗传材料与信息。

Morphological Characters and Inheritance of Incomplete Seed Coat in Two Induced Soybean Mutants

Soybean incomplete seed coat shows a complex genetic characteristics,and its role in soybean growth and development remains unclear.To reveal the genetic mechanism and new key genes involued in incomplete seed coat,different new mutants were created from soybean varieties by using physical and chemical mutagens for further trait evaluation.It showed that one mutant scd-KF was identified from an M3 line from Kefeng 1 Hao induced population by 60Co gamma ray irradiation,and another one scd-NN was found from the Nannong 1138-2 M4 population treated with ethyl methyl sulfonate.The seed coat of the scd-KF mutant showed longitudinal or transverse crack at back of seed at early stage of seed maturity.The cracking size varied according to the seed size.The seed coat deficiency of scd-NN mutant happened at the early stage of seed development,which was longitudinal at back of seed.There were obvious cracks between two cotyledons,and the seed was significantly smaller than the wild type.Genetic analysis showed that the incomplete seed coat of scd-KF mutant was controlled by a pair of recessive gene while the trait of scd-NN mutant might be controlled by two pairs of recessive genes according to the segregation ratio of F2 generation.The values of the plant height,pods and seed number per plant and seed number per pod of the mutant plants were lower when compared to normal type in F2 generations.However,the differences among the most traits were not significant.The results can provide genetic materials and useful information for further studies on development of the seed coat and seed in soybean.