水稻细菌性条斑病抗性新品系的创制及其农艺性状分析

Development and Agronomic Traits Analysis of New Rice Resistance Lines to Xanthomonas oryzae pv.oryzicola

【目的】创制水稻细菌性条斑病抗性新品系,为进一步培育抗细菌性条斑病水稻新品种提供核心种质材料。【方法】通过多代回交、自交,结合分子标辅助选择技术和GSR40K芯片检测,以来自孟加拉国含抗细菌性条斑病Xo2基因的稻种资源BHADOIA 303为供体,以优良籼稻品种五山丝苗为受体,培育抗水稻细菌性条斑病株系,并分别通过田间成株期人工喷雾法和浸入法接种鉴定这些株系的抗病性,评价其农艺性状。【结果】分子标记和GSR40K芯片检测表明最终获得稳定携带Xo2基因片段的10个新品系(BC4F5);无论是喷雾法接种还是渗入法接种,导入抗病基因的株系和五山丝苗对细菌性条斑病的抗性均差异显著,10个测定株系均表现抗水稻细菌性条斑病,其平均病情指数为5.00~10.37,病斑长度为0.70~0.99 cm,其中以株系1~3抗性表现最好。这3个抗性较好的株系的农艺性状及产量性状指标有些与五山丝苗相似,其中株系1的千粒重、谷粒长、宽与五山丝苗相似,结实率优于五山丝苗;株系2每穗总粒数与五山丝苗相似,谷粒比五山丝苗长些、宽些,千粒重优于五山丝苗;株系3千粒重、结实率与五山丝苗相似,单株穗数优于五山丝苗。【结论】获得水稻细菌性条斑病抗性显著增强且农艺性状较优良的3个株系,为细菌性条斑病抗病育种提供了抗性新材料,有利于加快水稻细菌性条斑病抗性分子育种进程。

【Objective】This study aims to develop new rice resistance lines to bacterial leaf streak(BLS)and provide core germplasm materials for BLS resistance breeding.【Method】BHADOIA303 harboring the Xo2 gene from Bangladesh was used as the BLS resistance donor,and an elite indica variety Wushansimiao was chosen as the recipient,to develop resistant lines by advanced backcrossing,molecular marker-assisted selection and GSR40K chip detection.The BLS resistance lines was evaluated by artificial inoculation with pathogen inoculum spraying and syringe infiltration in the field,and their agronomic traits were evaluated synchronously.【Result】Molecular markers and GSR40K microarray detection confirmed the presence of the target gene Xo2 in 10 new lines(BC4F5).Significant differences were observed in the BLS resistance between the introgression lines and Wushansimiao,no matter whether they were inoculated by spraying or infiltration.The average disease index ranged from 5.00 to 10.37,with an average lesion length of 0.70 to 0.99 cm.Lines 1-3 showed the best resistance.The agronomic and yield traits of the 3 lines with better resistance were comparable to those of Wushansimiao.The 1000-grain weight,grain length and width of line 1 were similar to those of Wushansimiao,and its seed setting rate was better than that of Wushansimiao.Number of total grains per panicle of Line 2 was similar to that of Wushansimiao with longer and wider grains,and a higher 1000-grain weight.The 1000-grain weight and seed setting rate of Line 3 were similar to those of Wushansimiao,and the number of panicles per plant was better than that of Wushansimiao.【Conclusion】Three Xo2 resistance lines with better agronomic traits and greatly enhanced resistance to BLS were obtained,which would provide resistance elite germplasm materials and accelerate the process of BLS resistance molecular breeding.