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1.
The rice( Oryza L. ) variety, Lijiangxintuanheigu(LTH), is a universally susceptible variety. A set of near-isogenic lines (NILs) of rice which has single resistance gene for each line was developed by use of LTH as recurrent parent and Kusabue,Tsuyuake, K1, PiNo. 4, K60 and BL1, which are from Kiyosawa‘s differential varieties(KDV), as donor parents. Differentiating ability of these NILs to Philippine isolates was compared with that of their donor parents, KDV and IRRI‘ s NILs. The results of comparative studies were as follows: (1) Differentiating ability of Chinese NILs to Philippine isolates was much stronger than that of their donor parents and that of KDV. (2) Chinese NILs had similar ability to differentiate races to IRRI‘s NILs or higher differentiating ability than them. But IRRI‘s NILs almost had no differentiating ability to isolates from japonica rice-growing regions. They can not be used to differentiate races of isolates from japonica ricegrowing regions. Whereas, Chinese NILs can be used to differentiate races of isolates from both japonica ricegrowing regions and indica rice-growing regions. It was concluded that the set of Chinese NILs can be used as international differentials.  相似文献   
2.
以两个三系杂交水稻组合来测定水稻对稻瘟病的抗性与野败型雄性不育性的遗传关系,以一个二系杂交水稻组合来测定水稻抗瘟性与光敏不育性的遗传关系。结果表明,水稻抗瘟性(对88-9菌株,ZB15小种)与野败不育性是独立遗传的;抗瘟性与光敏不育性是连锁遗传的,交换值接近40.90。  相似文献   
3.
粳稻品种(系)抗稻瘟病特性分类的研究   总被引:2,自引:0,他引:2  
用日本7个粳型单基因鉴别菌系将黑龙江省的一些粳稻品种(系)初步划分为8个抗性基因型:砦1号型、PiNo.4、Zenith型、福锦型、杜稻型、下北型、关东51号型、爱知旭型;根据供试品种(系)对黑龙江省四个优势小种的反应,将其划分为8个抗性类群,用日本鉴别菌系鉴定属于同一类群的品种,而用黑龙江省优势小种鉴定又被划分为不同类群,这说明同一抗性类型的品种可能含有相同的抗性基因,也可能含有不同的抗性基因。此外,在供试的粳稻品种(系)中没有发现对黑龙江省优势小种呈全抗反应类型的品种(系)。  相似文献   
4.
小麦麦瘟病,由梨孢菌小麦专化型(Magnaporthe oryzae, sp. Triticum, MoT) 侵染所致,最早于1985年在巴西发现,随后传播到其他南美国家。2016与2017年,麦瘟病登陆亚洲,相继在孟加拉国和印度暴发,对亚洲乃至全世界的小麦生产形成了潜在威胁。近年来,世界各国的科学家对麦瘟病进行了广泛和深入的研究,取得了较大进展。本文对小麦麦瘟病病原菌、侵染过程、流行因素和小麦抗病基因的研究进展进行了综述,并介绍了小麦麦瘟病抗性评价的方法。本研究组研究发现,在人工接种条件下,水稻来源的稻瘟病菌株(MoO)可侵染小麦引起典型麦瘟症状。笔者认为,虽然目前我国还没有麦瘟病发生的报道,但部分地区存在麦瘟病的发病条件,随着全球气候变暖麦瘟病有暴发的可能,需引起高度重视。建议加快麦瘟病发病机理及小麦抗性基因发掘的研究,以提升我国麦瘟病的研究水平,并为预防麦瘟病的发生未雨绸缪。  相似文献   
5.
部分云南粳稻品种的抗瘟性分类   总被引:11,自引:3,他引:11  
 根据云南部分粳稻品种对7个菌系的反应型,将596个粳稻品种划分为35群。借助单基因鉴别品种,推断了50个品种的基因型。应用致病谱广的北方小种,筛选出一批新抗源,满足抗病育种对抗源的需求,也为系统的抗病基因分析奠定物质基础。  相似文献   
6.
从采自全国各地的48份土样中分离得到放线菌403株。以水稻稻瘟病菌为指示菌,利用平皿对峙法筛选到30株具有较好拮抗作用的菌株,其中菌株WM2-4的拮抗作用最强,抑菌带宽度为22.2mm。结合抑制菌丝生长速率法进行复筛,结果表明菌株WM2-4对稻瘟病菌的抑制效果最好,抑制率为89.35%。根据形态特征、培养特征、生理生化特征及16S rDNA序列比对分析,初步鉴定菌株WM2-4为鲜黄链霉菌(Streptomyces galbus)。  相似文献   
7.
8.
To control rice blast effectively at the nursery stage, the absolute SiO2 content necessary for rice plants to resist blast disease was investigated using various rice cultivars and soils. Nine rice cultivars with different complete resistance genes and different degrees of partial resistance were grown on nursery soils amended with silica gel at different rates to change the SiO2 content of rice plant. The rice seedlings were then inoculated 28 days after sowing with Pyricularia grisea to estimate their blast resistance. In all rice cultivars, the number of lesions was significantly reduced when SiO2 content increased in the rice seedling; lesions were reduced to 5%–20% of the number on the seedlings grown in soil without silica gel when the seedling SiO2 content reached 5%. Additionally, the susceptibility to blast disease of rice seedlings grown on eight soils collected from different districts, with varying amounts of silica gel, was compared. The number of lesions decreased significantly when the SiO2 content in the seedlings reached 5%. These results suggest that SiO2 content of at least 5% in the rice plant can control this disease at the nursery stage under any conditions.  相似文献   
9.
杂交稻稻瘟菌致病菌系的组成及其变化   总被引:7,自引:0,他引:7  
对四川省大面积主栽杂交稻组合汕优63、汕优2号上的稻瘟病菌进行生理小种测定的结果表明,致病菌系由多个生理小种群组成,其中以ZB、ZC群小种为主。用不同生理小种的菌株接种汕优2号和汕优63的结果表明:ZB群小种对汕优2号的致病频率最高,为100%,而不同生理小种群对汕优63的致病频率无显著差异,平均为75%。致使这两个杂交稻组合丧失抗性的菌株来自四川省发病多年的常规稻、雄性不育系和早熟杂交稻组合。四  相似文献   
10.
Leaf blast suppression in multilines was evaluated based on the number of susceptible lesions observed in a pure stand of susceptible rice cultivar Sasanishiki, and in 1 : 1 and 1 : 3 mixtures of Sasanishiki and a resistant near-isogenic line, Sasanishiki BL4 or BL7, from 1998 to 2001. The number of lesions first observed in fields in the 1 : 1 and 1 : 3 mixtures were close to theoretical numbers calculated using the number of lesions observed in the pure stands and the ratios of the susceptible Sasanishiki in the mixtures. The ratio of the number of lesions in the 1 : 1 and 1 : 3 mixtures to the number in the pure stand was 0.29 and 0.09, respectively. The relationship between these ratios and the ratios of susceptible Sasanishiki in mixtures was defined in an equation to estimate the degree of leaf blast suppression. Validation studies for the ratios of the number of lesions in the 1 : 1 and 1 : 3 mixtures to the number in the pure stand were conducted in two different locations and showed that the ratios are almost acceptable. The calculated autoinfection to alloinfection ratio was 1.3 and 1.4 in the 1 : 1 and 1 : 3 mixtures, respectively, suggesting that the calculated ratio will affect the degree of leaf blast suppression. Thus, predictors were obtained to estimate leaf blast suppression for effective blast control in multilines.  相似文献   
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