水稻纹枯病立枯丝核菌的分类及遗传多样性研究进展

水稻纹枯病是一种世界性病害,目前该病已成为限制水稻高产、稳产的主要障碍之一。本文简述了引起水稻纹枯病的病原菌立枯丝核菌的形态特征,概述了依据菌丝形态特征和融合群进行分类的概况,阐述了同工酶、RAPDI、SSR和AFLP等分子生物学技术在水稻纹枯病菌遗传多样性研究中的应用。     

浙江省水稻纹枯病菌的遗传分化与致病力研究

鉴定了从浙江省各地采集的60株水稻纹枯病菌株的菌丝融合群归属情况。该60个菌株均与AG-1融合群的3个亚群AG-1-ⅠA、AG-1-ⅠB、AG-1-ⅠC的标准菌株融合,当属AG-1融合群。其中,有58株均与标准菌株AG-BⅠ融合,所有菌株与其他标准菌株均无融合现象。通过离体接种对菌株致病力进行鉴定,发现各菌株间致病力差异显著。致病力最强的TTZF-1与其中52个菌株差异极为显著。进一步的转录间隔区(ITS)序列分析显示,系统发育树的结果与融合群鉴定的结果一致,与菌株间致病力差异无相关性。     

大豆品种对立枯丝核菌的抗性研究!

运用种子腐烂率测试法对208份大豆材料进行测试,研究了根腐病原菌中立枯丝核菌对大豆的致病性,并对抗大豆立枯丝核菌抗源材料进行筛选。结果表明:立枯丝核菌是大豆根腐病病原菌中致病性较强的一种,大部分品种对立枯丝核菌高度感病,高感品种(系)153个,占参试材料的73.55%;高抗品种(系)21个,占参试品种(系)的10.1%,其中有7个来自国外;中抗品种(系)34个,占参试品种(系)的16.35%,其中12个中抗材料为创新改良的稳定品系。     

水稻立枯丝核菌G蛋白β亚基基因的克隆、表达及序列分析

根据Thanatephorus cucumeris G蛋白β亚基序列（AY884129）设计引物,对水稻立枯丝核菌AG 1IA的 G蛋白β亚基基因进行了克隆。PCR结果得到1条约为1.9 kb的扩增片段,包含1个约1.7 kb的完整开放阅读框,编码366个氨基酸。同源性检索发现该序列与大量Ｇ蛋白β亚基基因明显同源,一致性介于57.34%~88.14%。根据其推导cDNA序列设计引物进行RT PCR分析,发现该基因在对数生长期表达量最高,提示水稻立枯丝核菌AG 1IA G蛋白β亚基基因可能具有时空表达特性。     

立枯丝核菌毒素对人参PAL活性及细胞膜透性的影响

用不同浓度的立枯丝核菌粗毒素处理一年生人参幼苗,检测24h内人参幼苗叶片内苯丙氨酸解氨酶(PAL)活性和细胞膜相对透性变化。结果表明:经立枯丝核菌粗毒素处理后人参细胞中PAL的活性呈现先升高后后降低的变化趋势,而细胞膜相对透性的变化则呈现持续上升的趋势。     

马铃薯黑痣病菌菌丝融合群的鉴定

从马铃薯种植区的部分县市分离纯化得到44个马铃著黑痣病病原菌立枯丝核菌（RhizoctoniasolaniKUhn）菌株,经核相测定均为多核菌株。通过与标准菌株AG-1-IA、AG_1-IB、AG_2—1、AG_2-ⅢB和AG．3的菌丝融合试验,最终将44个菌株分为3个菌丝融合群,即AG-3、AG--1-IB和非融合类...     

华南3省（区）水稻纹枯病菌的生物学性状与致病力分化研究

 为了探明华南地区水稻纹枯病菌的生物学性状、致病力分化与菌株地理来源之间的关系,为该病害的防治提供依据,从我国华南3省（区）广东、广西和海南的33个县（市）采集水稻纹枯病标本,在分离到335个水稻纹枯病菌菌株的基础上,对它们的培养性状（菌丝生长速率、菌落颜色、菌核数量）、菌丝融合群、菌丝细胞核数目以及致病力分化进行了研究。结果表明,菌株菌丝生长速率可划分为慢、中、快3种类型,菌株数分别为3株（0.90%）、136株（40.60%）和196株（58.50%）;产生菌核的数量可划分为4种类型,即无菌核或极少形成菌核、菌核量少、菌核量中等和菌核量多,各有4株（1.19%）、59株（17.61%）、238株（71.04%）和34株（10.15%）。菌株融合群测定结果表明,所有供试菌株均属于立枯丝核菌（Rhizoctonia solani）AG-1融合群的ⅠA亚群,即AG-1 ⅠA。从中随机选取50个菌株进行菌丝细胞核染色,结果显示,水稻纹枯病菌菌丝的细胞核数目介于7～13个。对其中270个菌株的致病力测定结果表明,所有供试菌株可划分为中等致病力和强致病力2个致病型,分别为208株（77.04%）和62株（22.96%）,未发现弱致病力菌株。综合分析表明,所测菌株的致病型与菌丝生长速率及菌核产生数量各异,表现出较大的多样性。     

大玫北方 枯病菌与其轮作物丝核菌的生物学特性及致病力比较研究

对大麦纹枯病菌与其轮作物丝核菌比较研究表明,它们除具有丝核菌的共同特点外,在菌落形态和菌核形成等性状上,均有明显差异;人工交互接种结果显示,各分离物对原寄主都表现出强致病力,呈现典型纹枯或立枯症状,但对其它作物的致病力差异较大。     

Genetic Diversity and Pathogenicity Variation in Rhizoctonia solani Isolates from Rice in Sichuan Province, China

Fifty-five representative samples of Rhizoctonia solani isolates, which were collected and isolated from five different ecological regions in Sichuan Province, China, were purified and analyzed for the pathogenicity and molecular genetic variation. The hyphal fusion test revealed that almost all the isolates belonged to the AG-IIA group except the isolate D42. In addition, some of the isolates were ‘bridging isolates’, which could fuse with several groups simultaneously. The pathogenicity analysis on in vit...     

海南南繁区水稻纹枯病菌的遗传多样性与致病力分化

【目的】为明确南繁区水稻纹枯病菌(RhizoctoniasolaniAG-1IA)的遗传分化及遗传多样性与致病力的关系,【方法】采用AFLP分子标记技术和离体叶片接种法对南繁核心区(三亚、乐东、陵水)和非核心区(琼中、屯昌和定安)共60株水稻纹枯病菌的遗传多样性、遗传结构和致病力分化进行了测定,并分析了遗传多样性与致病力之间的关系。【结果】聚类分析结果表明,核心区菌株的遗传多样性相对更高;群体遗传结构分析表明,核心区群体的多态性位点百分率(PPL)、Nei基因多样性指数(H)、Shannon信息指数(I)和基因流(N_m)分别为82.24%、0.1932、0.3062和2.5627,高于非核心区群体的67.49%、0.1535、0.2447和0.9365;而核心区群体的基因分化系数(G_st)为0.1633,低于非核心区群体的0.3481。【结论】核心区菌株的遗传变异程度比非核心区菌株高;核心区不同群体间存在较多的基因交流,而非核心区菌体间的基因交流较少,但遗传变异均主要来自于群体内;总体而言,核心区菌株的遗传分化程度更高。菌株的致病力及其与菌株遗传多样性的相关性分析表明,核心区菌株以中等致病型为主,而非核心区菌株则以中、强致病型为主,但与菌株的AFLP谱系之间的相关均未达显著水平。     

云南水稻抗白叶枯病品种的遗传多样性初报

利用RAPD技术,从90个RAPD引物中筛选出20个引物,通过PCR扩增,对53份抗白叶枯病水稻品种进行遗传多样性分析。结果表明,供试的水稻品种间遗传分化明显,具有丰富的遗传多态性。经聚类分析可知,抗病品种与感病品种遗传差异很大,很容易区分开,在遗传距离为0.2时,测试的51个抗白叶枯病水稻品种可分为13个遗传相似组,其中1、2、5组为主要主群,分别包括8个、17个和9个品种。     

Diversity Analysis in Selected Non-basmati Scented Rice Collection

Diversity analysis among 23 rice varieties including 16 non-basmati scented accessions, 5 basmati accessions and 2 non-scented accessions was performed by random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) marker systems. The varieties analyzed by 11 RAPD and 8 ISSR primers yielded an average of 65% and 80% polymorphism, respectively. The average number of polymorphic bands generated per RAPD primer was 6 and per ISSR primer was 5.87. RAPD and ISSR data analysis individually could not segregate basmati and non-basmati scented rice accessions. However, the analysis using a combined data could group basmati and non-basmati scented rice accessions separately. The bands present specifically among three accessions of non-basmati scented rice were also identified. The study revealed a high genetic diversity among non-basmati scented rice accessions.     

贵州地方水稻品种的SSR遗传多样性分析

利用21对SSR引物对74份贵州"禾"水稻品种及6份国际上常用的典型籼稻和粳稻品种进行遗传多样性研究。共检测到92个等位基因,每个位点的等位基因数变幅为2~9个,平均4.381个;平均Shannon信息指数为0.935,变幅为0·2793~1.8732;期望杂合度为0.5145,范围在0.0988~0.8313;品种间遗传相似系数为0.64~0.98。UPGMA聚类分析表明,在相似系数为0.682处可将"禾"品种分为4大类,大部分材料被聚类到典型粳稻的附近,品种间的亲缘关系与地理来源关系不大;主坐标分析结果与UPGMA聚类结果基本吻合。SSR检测结果表明,贵州省水稻地方品种——"禾"的多样性程度较低,且大多数属于粳稻。     

Genetic Diversity and Relationship of Weedy Rice in Taizhou City, Jiangsu Province, China

Microsatellite markers and morphological charactedstics were used to explore the genetic diversity and possible origin of weedy dce in Taizhou City, Jiangsu Province, China. Fifty-two weedy rice (Oryza sativa L.) accessions were compared with two wild rice, four hybdd rice and five cultivars using 22 simple sequence repeat (SSR) primer pairs. A total of 107 fragments were amplified, averaging 5.6 alleles per primer pair. The polymorphic index content (PIC) values ranged from 0.3077 to 0.7951, averaging at 0.5870. The average genetic distance of all samples ranged from 0.02 to 0.46 with an average of 0.262. The genetic distance among Taizhou weedy rice ranged from 0.03 to 0.44 with an average of 0.224. Cluster analysis showed that all the weedy rice accessions from Taizhou City were indica, and could be subdivided into different genotypes. The majority (86%) of weedy rice was most closely related to hybrid rice. The Taizhou weedy dce accessions were morphologically similar, but still could be delineated into indica or japonica group by some morphological traits. it is suggested that the levels of genetic and morphological diversities of weedy rice in Taizhou City are low and these weedy rice plants originated from the segregating progenies of hybrid rice that had naturally introgressed with cultivated rice.     

我国杂交水稻主要恢复系的DNA多态性研究

利用RAPD引物对我国杂交稻主要的31个恢复系进行了DNA多态性分析。从152个随机引物中筛选出48个引物扩增恢复系的基因组DNA,选取9个引物的扩增结果进行分析,共获得78条带,其中61条带为多态性标记,每个引物平均提供8.7个标记信息。由UPMGA方法得到的聚类分析结果表明了31个恢复系间的亲缘关系,聚类结果与它们的系谱关系基本吻合。