【作者】 郑艳；

【导师】 黄富；

【作者基本信息】 四川农业大学 ， 植物病理学， 2008， 硕士

【摘要】 由Magnaporthe grisea（Hebert） Barr引起的稻瘟病是世界性水稻主要病害之一。实践证明,选育和种植抗病品种是控制该病害最经济有效的措施。抗病种质资源的发掘、研究与利用是水稻抗稻瘟病育种的重要基础。本文在分析了四川稻区稻瘟病菌生理小种组成、分布及四川主要杂交稻品种抗瘟性鉴定的基础上,对72份广东水稻种质资源和本实验室多年收集的457份水稻种质资源进行了叶瘟和穗瘟的抗瘟性鉴定,然后对72份广东水稻种质资源和部分抗源的恢、保特性进行了评价,在四川生态条件下对72份广东水稻种质资源的农艺性状进行了观察,并对利用不育系宜香1A与广东水稻种质配制的72个F₁组合中的部分组合的农艺性状的竞争优势和米质性状进行了评价。结果表明,2007年,四川稻区稻瘟病菌由4个群24个小种组成,其中ZA群出现频率为39.77%,为重要小种群,ZB群出现频率为57.95%,为优势小种群。ZB₁₃（22.73%）为优势小种,重要小种还有ZA₁₃（17.05%）、ZB₉（7.95%）。泸州、雅安、蒲江等不同生态区的稻瘟病菌生理小种组成有差异。目前,四川的主栽品种稻瘟病抗性都不高,在参试的46个品种中,中抗至高抗稻瘟病的品种只有19个。稻瘟病抗性鉴定结果表明,72份广东种质资源穗瘟1～3级的抗病品种52个,占72.22%,457份种质资源穗瘟1～3级的抗病品种239个,占52.30%。恢保特性测定结果表明,72份广东种质资源中,45份材料对三系不育系具有恢复性,8份具有保持性,19份具有半恢半保特性;测定的27份抗源材料中,9份具有恢复性,6份具有保持性,3份具有半恢半保特性。农艺性状测定结果表明,多数广东水稻种质在四川生育期属中籼中、迟熟类型,株高相对较低,分蘖较强,穗子中等偏小,结实率、千粒重及单株产量较低。通过农艺性状表型聚类可将72份广东水稻种质资源分为3大类,Ⅰ类20份,属中等穗型,平均结实率83.3%;Ⅱ类21份,属大穗型,平均穗着粒180粒左右;Ⅲ类31份,其生育期较短,植株较矮,穗子较小。通过竞争优势的主成分聚类将45个F₁组合划分为3类:Ⅰ类有18个组合,该类株高、单株穗数及穗着粒数3个性状的竞争优势为正值,播始天数、穗实粒数、结实率、千粒重及单株粒重5个性状为负值;Ⅱ类有11个组合,该类单株穗数、穗着粒数、穗实粒数及单株粒重4个性状的竞争优势为正值,其余性状为负值;Ⅲ类有16个组合,该类单株穗数及穗着粒数2个性状的竞争优势为正值,其余性状为负值。在57个F₁组合中,糙米率及垩白米率分别达国标1、2、3级优米标准的组合数为12个、20个、18个及16个、28个、6个。此外,本文还对这些抗源改造利用的策略进行了讨论。更多还原

【Abstract】 Rice blast, caused by Magnaporthe grisea （Hebert） Barr, is one of the most devastating plant diseases, infecting rice crops all over the word. It has been proved that breeding and planting disease-resistant cultivars is the most economical and efficient means to control this disease. Screening and utilization of rice resources resistant to blast is the foundational measure to breed resistant varieties. This study focuses on rice growing area in Sichuan province, thoroughly analyzing the composition, distribution of blast fungus races ,and the rice blast resistance identification in main hybrid rice varieties, and the rice blast resistance identification in 72 rice germplasm resources from Guangdong province and 457 rice germplasm resources from our self collecting by leaf blast and panicle blast, and evaluating restoring or maintaining characteristics for 72 rice germplasm resources from Guangdong province and some of the resistant resources. Moreover, the agronomic characters of 72 rice germplasm resources from Guangdong province were observed in Sichuan province, and the competition superiority of agronomic traits and the grain quality of some combinations in 72 combinations from Yixiang A-line and Guangdong rice resources were evaluated.The result showed that the pathogen in Sichuan province were composed of 4 groups containing 24 races, in which ZA and ZB group were predominate with a frequency of 39.77% and 57.95% respectively, and ZB₁₃ was the predominate with a frequency of 22.73% and other main races were ZA₁₃ （17.05%）, ZB₉ （7.95%）. The composition of blast fungus races among different ecological regions such as Luzhou,Yaan and Pujiang disease nurseries were different .At present, the blast resistance of the main rice varieties in Sichuan was low. There were 19 varieties which were showed high or medium in blast resistance. The result of rice blast resistance identification indicated that 52 Guangdong and 239 rice germplasm resources were resistant to rice blast, occupied 72.2% and 52.30% respectively, with panicle neck blast of 1-3 scales. Among 72 Guangdong rice germplasm resources and 27 resistant resources, 45 Guangdong resources and 9 resistant resources had restoring character to male-infertile lines, 8 Guangdong resources and 6 resistant resources had maintaining character to male-infertile lines and 19 Guangdong resources and 3 resistant resources had restoring and maintaining character to male-infertile lines. The result of agronomic characters identification indicated that most of the 72 Guangdong rice resources belonged to medium or late mid-Indica, with low plant height, strong tiller, medium or small panicle, low seed setting, low 1000-grain weight and low grain yield per plant. The 72 Guangdong resources might be divided into 3 groups by using cluster analysis based on agronomic characters. Group I had 20 resources, with mid-panicle, 83.3% of the average seed setting. Group II had 21 resources, with big panicle, about 180 spikelets of the average spikelets per panicle. Group III had 31 resources, with small panicle, short growth period and low plant height. The 45 hybrid combinations were divided into 3 groups by using principal component analysis and cluster analysis based on competition superiority. Group I had 18 combinations, with the positive competition superiority of plant height, panicles per plant and spikelets per panicle, the negative competition superiority of the period of from sowing to heading, filled spikelets per panicle, seed setting, 1000-grain weight and grain yield per plant. Group II had 11 combinations, with the positive competition superiority of panicles per plant, spikelets per panicle, filled spikelets per panicle and grain yield per plant, the negative competition superiority of other traits. Group III had 16 combinations, with the positive competition superiority of panicles per plant and spikelets per panicle, the negative competition superiority of other traits. Among the 57 hybrid combinations, the brown rice rates of 12,20 and 18 hybrid combinations reached the first, second and third grade of the national high quality rice standards respectively. The chalky rice rates of 16, 28 and 6 hybrid combinations reached the first, second and third grade of the national high quality rice standards respectively. Finally, the strategies of improvement and utilization of these rice resistance resources were also discussed.更多还原