水稻品种多样性遗传分析与稻瘟病控制(英文)

Genetic Analysis of Rice Varietal Diversity for Rice Blast Control

以 2个籼型杂交稻———汕优 6 3(A)和汕优 2 2 (B)、2个地方糯稻品种———黄壳糯 (C)和紫糯 (D)和 3个粳稻品种———合系 4 1(E)、楚粳 12 (F)和 812 6 (G)为材料进行抗病基因同源序列 (ResistanceGeneAnalogue ,RGA)遗传分析。结果表明 ,杂交稻品种间以及粳稻品种间的抗性遗传较为相似 ,其相似系数分别为 0 86和 0 84。糯稻品种间以及糯稻、杂交稻和粳稻间的抗性遗传差异较大 ,相似系数为 0 4 5。聚类分析表明 ,RGA结果与品种的系谱来源相吻合 ,与品种的田间抗性基本一致。根据品种的抗性遗传差异、农艺性状和经济性状的不同 ,在云南籼稻区的建水和石屏县以及温暖粳稻区的泸西县分别选用 5种 (A/C、A/D、B/C、B/D和A/B)和 2种 (E/C和E/F/G)不同的品种组合进行品种多样性混合间栽控制稻瘟病田间试验 ,结果表明 ,抗性遗传差异大 (相似性 :0 4 5～ 0 77)的 5个品种混合间栽组合对稻瘟病有极为显著的控制效果 ,尤其是在混合间栽中高度感病的优质地方稻品种稻瘟病的发病率、病情指数均有极显著的下降 ,防治效果达 5 4 4 7%～ 92 18% ;遗传差异较小 (相似性 :0 84～ 0 90 )的 2个混栽组合混栽对稻瘟病的控制效果不明显 ,稻瘟病的防治效果在 15 12 %～ 2 5 5 4 %。此外 。

Two Indica hybrid rice of Shanyou63 (A) and Shanyou22 (B),two glutinous landraces of Huanghenuo (C) and Zinuo (D) and three improved Japonica rice of Hexi41 (E),Chujing12 (F) and 8126 (G) were selected and their genetic resistance relationship was estimated using resistance gene analogue (RGA).The results showed that there were similar genetic relationships between hybrid varieties at the genetic similarity (GS) of 0.86,and among improved Japonica varieties at the GS of 0.84,while highly genetic diversifications between traditional varieties,Indica and Japonica varieties,traditional and modern variety (GS:0.45).The results also showed that clustering analysis based on RGA data were generally corresponded to known pedigrees and blast field resistances of the varieties.Based on varietal differences in RGA data and agronomic traits,plot experiments of five mixed-planting combinations of A/C,A/D,B/C,B/D and A/B and two combinations of E/C and E/F/G were conducted in Jianshui and Shiping counties (Indica rice growing region) and Luxi County (warm Japonica region) in Yunnan Province in past two years,respectively.The results demonstrated that rice blast management was more effective in five mixed-planting combinations of varieties with different genetic backgrounds (GS:0.45～0.77) than in two combinations with similar genetic relationships (GS:0.84～0.90),compared with their monocultures.It is evident for the highly susceptible landraces in mixed-planting to achieve disease control,with significant decreases both in incidence and severity.The blast control efficiencies of landraces in different mixture combinations reached to 54.47%～92.18%.The control efficiencies of improved varieties varied from 15.12% to 25.54% in mixture combinations with closed genetic relationship.In addition,the total yield of 5 varietal combinations with distant genetic relationship increased 539.0～904.0 kg/ha in the mixed-planting plots,at increase rates of 5.6%～10.2%.Mixed rice varieties with similar genetic background did not achieve significant yield increase.Otherwise,the yield of E/F/G decreased 2.7%～4.0% compared with pure stand.The results can provide scientific basis of varietal combinations in diversification experiments for blast control.