Identification of S-genotypes in 18 pear accessions and exploration of the breakdown of self-incompatibility in the pear cultivar Xinxue
Identification of S-genotypes in 18 pear accessions and exploration of the breakdown of self-incompatibility in the pear cultivar Xinxue
复制标题
18份梨材料S基因型鉴定及新雪梨自交不亲和性解析
DOI：
10.1016/j.scienta.2018.05.003
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发表时间：
2018
影响因子：
4.3
通讯作者：
Zhang Shao-Ling
中科院分区：
文献类型：
--
作者：
Shi Su-Li;Cheng Hai-Yan;Wu Lei;Xie Zhi-Hua;Gu Chao;Zhang Shao-Ling
Self-incompatibility is a genetic mechanism in flowering plants that promotes outcrossing and prevents inbreeding. In this study, the reported 15S-RNasealleles were isolated from 18 pear accessions that contained 14 differentS-genotypes. TheS-RNasealleles were only expressed in the style, not in the root, stem, leaf, fruit, sepal, and pollen. Pollen tube grew into self-styles and self-pollinated fruit set involved the breakdown of self-incompatibility in cv. Xinxue. However, the twoS-RNasealleles in cv. Xinxue had identical amino acid sequences to those self-incompatible cultivars, andS5-andS6-RNasewere normally expressed in style, indicating that the loss of self-incompatibility in cv. Xinxue likely resulted from pollen-part mutation. Further,S5S5andS6S6genotyped individuals were identified in self-pollinated progeny, indicating thatS5andS6genotyped pollen were compatible with the self-styles of cv. Xinxue. A genetic analysis showed that the segregation ratio ofS5S5,S5S6, andS6S6was approximately 0:2:1 (χ2= 3.505 < χ20.05, 2= 5.99), which did not fit the theoretical ratio of 1:2:1 (χ2= 13.340 > χ20.05, 2= 5.99), suggesting that the breakdown of self-incompatibility could be caused by modified factor(s) located outside of theS-locus. These results are useful for parental assignment and understanding self-incompatibility reaction.
