Abstract:

【Objective】Rice blast is one of the most important diseases in rice production and poses a serious threat to global rice production. The large-scale and long-term planting of varieties with a single resistance gene often leads to the loss of resistance. Molecular marker-assisted selection is one of the most effective approaches for controlling rice blast..【Method】Using Taifeng B as the recipient, and Shuangkang 77009 carrying Pigm-1 and Digu B carrying Pid2 as donors, respectively. The genotypes of each generation were analyzed and identified by means of hybridization, backcrossing, backcrossing and recurred cross, aided by molecular marker-assisted breeding. Subsequently, the blast resistance of the developed sterile line Fumeng A and its hybrids was evaluated using 12 blast isolates from diverse sources under natural field conditions. Finally, through field trials, the fertility, main agronomic traits, combining ability, and heterosis of Fumeng A were systematically analyzed, and the photo-sensitive characteristics of its corresponding restorer line were also examined.【Result】A new three-line male sterile line, Fumeng A, carrying both Pigm-1 and Pid2, was developed. Inoculation tests both in the laboratory and field confirmed its blast resistance. Fertility identification showed that both the sterility rate and sterility degree of Fumeng A reached 100%, with a stigma exsertion rate of 57.39%. Genetic background and agronomic trait analysis indicated that Fumeng A inherited the main agronomic traits of the recurrent parent and exhibited improved yield potential. Heterosis analysis revealed that half of the hybrid combinations derived from Fumeng A yielded higher than the control variety Tianyouhuazhan, demonstrating good potential for production application.【Conclusion】Using molecular marker-assisted selection, a novel three-line male sterile line, Fumeng A (B), with high blast resistance, stable sterility, high stigma exsertion, and excellent agronomic and yield traits was developed. This work achieved targeted improvement of blast resistance in a sterile line and created a new parental material for three-line hybrid rice breeding.

Key words: rice, resistance to rice blast, Pigm-1, three-line sterile line, polymerization breeding, photoinhibition

摘要：

【目的】水稻稻瘟病是水稻生产上最主要的病害之一，对全球水稻生产构成严重威胁。大规模和长期种植具有单一抗性基因的水稻品种通常会导致抗性的丧失。通过分子标记辅助选择技术，选育抗病品种是防治稻瘟病最有效的方法之一。【方法】首先，以泰丰B为受体，分别以携带Pigm-1的双抗77009和携带Pid2的地谷B为供体，通过杂交、回交和复交的方法，并借助于分子标记辅助育种技术，对各世代单株基因型进行分析与鉴定。其次，利用不同来源的12个稻瘟病菌和田间自然鉴定的方法对选育的福梦A及组合进行抗性鉴定。最后，通过田间种植与调查，对不育系福梦A的育性、主要农艺性状以及配合力与杂种优势进行系统的分析，并对其抑制恢复系感光的特性进行了分析。【结果】培育一个同时含有稻瘟病抗性基因Pigm-1和Pid2新的三系不育系福梦A，室内与田间接菌显示该不育系抗稻瘟病；育性鉴定结果显示福梦A不育株率和不育度均为100%，柱头外露率达57.39%；遗传背景与农艺性状分析显示福梦A遗传了轮回亲本的主要农艺性状，具有更好的丰产性；杂种优势分析显示，福梦A配制组合其产量有一半高于对照天优华占，具有较好的生产应用潜力。【结论】通过分子标记辅助育种技术，育成1个高抗稻瘟病、不育性稳定、柱头外露率高、农艺性状和产量性状优良的新三系不育系福梦A(B)，实现了不育系稻瘟病抗性的定向改良，为三系杂交水稻育种应用创制了新的亲本材料。

关键词: 水稻, 抗稻瘟病, Pigm-1, 三系不育系, 聚合育种, 抑制感光