粳稻杂种劣势的遗传及表型特性分析  

Inheritance and Phenotypic Characterization of Hybrid Weakness in Japonica Rice

作　　者：张慧[1] 李东宣[1,2] 魏振飞[1] 钱树琪[1] 冯德党[1] 谢小东[1] 熊海波[1] 徐家星[1] 甘树仙[1] 朱骞[1] 张小玲[1] 谭学林[1,2] 陈丽娟[1,2] 

机构地区：[1]云南农业大学稻作研究所,昆明650201 [2]云南省高校滇型杂交粳稻分子育种重点实验室,昆明650201

出　　处：《分子植物育种》2012年第3期270-277,共8页Molecular Plant Breeding

基　　金：NSFC-云南联合基金重点项目(U1136604);国家重点基础研究973项目(2011CB100401);云南省水稻产业技术体系(A3006516)共同资助

摘　　要：杂种优势是自然界的一种普遍现象,但在杂交水稻育种实践中也时常发现杂种劣势现象,为了更好地阐明杂交育种理论和揭示品种本质有必要对杂种劣势的遗传机理进行更深层次的研究。本研究旨在通过两个韩国粳稻品种(Aranghyangchalbyeo和Sanghaehyangheolua)及其正反交后代(F1,F2)特性的比较,解析水稻杂种劣势的表型、类别及其遗传模式。形态学分析表明,正反交F1植株的劣势表现均明显、稳定且不受环境影响,主要农艺性状的中亲劣势值均为负值,其中F1的株高、分蘖数和结实率与亲本相比显著降低(P<0.01);F1劣势表现从发芽后第5d开始,地下部的劣势表现比地上部更为明显。细胞组织结构观察表明,分蘖盛期F1劣势植株叶片发育正常,而其根部气腔发育较亲本迟缓,从而阻碍了地上部与地下部的通气情况,因此也影响了整个植株的正常生长。遗传学分析发现,该劣势组合成熟期F2群体中正常与劣势植株呈现7:9的分离,结合分蘖盛期该F2群体株高的分离模式,推断该杂种劣势的表型是由两个互补的显性基因控制。该研究结果为揭示杂种劣势的多样性及分子遗传机制提供了新思路。Hybrid vigor is an universal phenomenon existed in nature, yet hybrid weakness phenomenon was also uncovered occasionally in the practice with applying hybrid rice breeding. Studies on the mechanisms of hybrid weakness is an essential for better understanding the principle of hybrid crop breeding as well as for revealing the nature of crop variety. This study was attempted to identify the phenotypic performances and genetic bases associated with hybrid weak in rice （Oryza sativa L.） based on the comparison of agro-biological characteristics in the progenies （G, F2） derived from the reciprocal crosses between two Korean Japonica varieties （Aranghyangchal- byeo and Sanghaehyangheolua）. Morphological analysis showed that hybrid weakness of F1 plants in the reciprocal crosses was observed obviously, stable and unaffected by environment. Meanwhile, mid-parent hybrid weakness of the main agronomic traits in the reciprocal crosses were negative, and plant height, tiller number and seed setting rate of F1 plants were significantly lower than that of parents （P〈0.01）. Hybrid weakness of F1 plants in the reciprocal crosses were emerged from the 5^th days after germination, showing more severe in the underground parts rather than the aboveground parts. Histological observations showed that the leaf development at tillering stage of F1 weakness plants was appeared to be normal, while its aerenchyma development of root was slower down significantly comparing to the parents, which resulted in impeding the ventilation of both aboveground and underground, and therefore affected the normal growth of the whole plant. Genetic analysis indicated that the ratio of normal plants to weakness plants at maturity stage was 7：9 in F2 progenies derived from the cross with hybrid weakness. Taking together observations on the segregation mode of plant height at tillering stage in F2 progenies derived from the cross with hybrid weakness, we concluded that this hybrid weakness was caused by two complementary dominant genes.

关 键 词：水稻 粳稻 杂种劣势 表型 遗传 

分 类 号：S511.22[农业科学—作物学]