稻秆潜蝇综合防治技术研究

稻秆潜蝇是浙南山区水稻生产的重要害虫.通过推广薄膜育秧、绿肥田除草、选用抗性品种、实行健身栽培、生态控制等一系列综合防治技术,可达到经济有效的防治效果.在水稻整个生长期可减少用药1～2次,稻秆潜蝇穗被害率减轻41.03%,病虫害损失控制在3.6%以内,稻谷增产9.2%,稻田害虫天敌蜘蛛和黑肩绿盲蝽分别增加38.1%和26.3%,获得了明显的生态、经济效益.     

Antifungal activity of 1,3-disubstituted symmetrical and unsymmetrical thioureas

1,3-disubstituted aliphatic and aromatic symmetrical and unsymmetrical thioureas were synthesised by novel routes and the antifungal activities of these compounds against two plant pathogens, Pyricularia oryzae and Drechslera oryzae were studied in Czapek-Dox medium at four different concentrations using acetone as the control and the structure-activity relationship among the substituted thioureas is reported. © 1998 SCI.     

Expression and homology modelling of sterol 14α‐demethylase of Magnaporthe grisea and its interaction with azoles

BACKGROUND: Magnaporthe grisea (Hebert) ME Barr infection is one of the most serious diseases for cultivated rice in the world. Sterol 14α‐demethylase (CYP51) is an important drug target for microbial pathogenic infections. To exploit specific and effective fungicides for M. grisea better, the authors have analysed the characteristics of interaction between sterol 14α‐demethylase from M. grisea (MGCYP51) and azoles. MGCYP51 with truncation of N‐terminal residues was cloned and expressed in E. coli, difference binding spectra of MGCYP51 induced by addition of four commercial azoles were determined and molecular modelling of MGCYP51 based on the crystal structure of Mycobacterium tuberculosis Lehmann & Newman and docking with the azoles were performed. RESULTS: The affinity of the azoles for MGCYP51 was positively correlated with their hydrophobicity. Amino acid residues Tyr112, Phe120, Phe220, His308 and Phe497 of MGCYP51, forming a large hydrophobic cavity, are the key residues interacting with azole fungicides. Furthermore, Phe220 and Phe497 are fungus and species specific respectively. CONCLUSION: The results suggest that the more potent azole fungicides for MGCYP51 should possess more hydrophobic groups interacting with residues Phe220 and Phe497. Copyright © 2009 Society of Chemical Industry     

抗白叶枯病菌水稻体细胞无性变异系离体筛选后代的生理生化特性

 对离体筛选的抗白叶枯病的粳稻105R、粳稻3037R后代植株功能叶的生理生化特性进行测定,结果表明:与未筛选的粳稻105S、粳稻3037S相比,筛选后代植株中可溶性蛋白质含量低,而酚类物质和木质素含量、过氧化物酶(PO)、多酚氧化酶(PPO)和苯丙氨酸解氨酶(PAL)活性均明显高于未经筛选的对照(感病)品种。由此说明离体筛选抗病品系的抗病机制与一般抗性品种类似。     

水稻稻瘟病菌研究进展

综述了水稻稻瘟病菌的研究进展 ,包括生理小种的鉴别、命名及演变 ,病菌致病性变异的原因及遗传、菌株的多样性以及病菌侵染与为害的机理。     

云南粳稻区水稻品种多样性田间稻瘟病菌群体的遗传结构

利用稻瘟病菌的一段倒位重复序列Pot2设计的一对引物,采用rep PCR分子指纹技术对来自云南省弥勒县粳稻种植区的水稻品种（净栽合系41、净栽黄壳糯、混栽合系41和黄壳糯）多样性田间242个稻瘟病单孢分离菌株的DNA进行扩增。结果显示所有供试菌株均扩增出2~28条谱带,扩增片段大小为400 bp~23 kb,但80%左右的片段集中在0.4~6.0 kb。将供试菌株扩增谱带进行聚类分析,比较了混栽与净栽田间病菌群体遗传结构的组成差异。结果表明,在粳稻种植区,水稻品种多样性种植有利于对稻瘟病菌的稳定性选择,在不同的遗传相似水平, 菌株遗传宗群复杂度与栽培方式有一定的相关性。混栽田间病菌遗传宗群较净栽田间复杂。在80％的相似水平上,净栽糯稻田间的稻瘟病菌被划为13个宗群,而混栽粳稻和黄壳糯田间由糯稻品种上分离的稻瘟病菌群体被划为20个宗群;净栽粳稻田间的稻瘟病菌可划为9个宗群,而混栽粳稻和糯稻田间由粳稻品种上分离的稻瘟病菌群体可划为15个宗群。     

水稻白叶枯病菌hrpF启动子序列调控的绿色荧光蛋白基因表达体系的构建

为了阐明启动子序列对水稻白叶枯病菌效应子基因表达的调控作用及特征,通过融合PCR将报告基因GFP基因置于水稻白叶枯病菌hrpF基因启动子序列的下游,经酶切、PCR鉴定及序列测定,成功构建了受hrpF启动子序列调控的GFP基因转录单元pMF-GFP,并转入JXO I菌株中。结果发现构建的hrpF：：GFP转录单元,在hrp诱导培养基XOM2上可有效诱导表达,而在NA培养基上不能诱导表达。结果还显示,在大肠杆菌中,中间表达载体phrpF：：GFP具有GFP表达活性。     

水稻白叶枯病菌单细胞系毒力分化研究

 以稀释倒平板法从0型菌086和IV型菌967-4和9620中分离到59个单细胞系;在12个近等基因系品种上,086和其单细胞系表现为弱毒力,2个IV型菌及其单细胞系能克服抗病基因Xa-1、2、3、8、10、11、14的抗性,不能克服Xa-21、4、5、7、13的抗性;带主效抗病基因的品种Asominori、XM5、M41、XM6和丰锦能把3个母株的59个单细胞系区分为12种数量差异或质量差异的不同致病型;将此5品种与近等基因系配合,适合作为病菌致病基因变异频度监测的寄主;采用"段叶沙培,切口取菌胶"法分离病菌,在中国致病型鉴定品种上划分的致病型,是田间病菌群体毒力结构的表型反应。     

两种十八碳二烯酸诱发水稻对稻瘟病的抗性及其防病作用

 研究了（１１Ｓ，１２Ｓ，１３Ｓ）－１１，１２，１３－三羟基０（９Ｚ，１５Ｚ）－十八碳二烯酸（Ａ）和（１１Ｒ）－羟基－１２（Ｓ），１３（Ｓ）－环氧－（９Ｚ，１５Ｚ）－十八碳二烯酸（Ｂ）的生物学活性。体外测试结果表明，这两种十八碳二烯酸对稻瘟菌菌丝生长只有轻微的抑制作用，而对分生孢子萌发则表现了较强的抑制作用，３－４叶期的水稻幼苗经这两种十八碳二烯酸诱发处理后均获得了对稻瘟病的抗性，减轻了稻瘟病的病情。用A处理后隔5 d接种稻瘟病菌，病情指数比对照降低64.8%；用B处理后隔2 d接种病菌，病情指数比对照降低69.8%。两种十八碳二烯酸均以5 μg/mL浓度诱发处理时，使水稻植株获得最大的诱导抗性。由A和B激发产生的诱导抗性对稻瘟病的防治效果均大于50%。先接种稻瘟病菌以诱发发病，而后隔5 d或10 d后喷施10 μg/mL的A或B水溶液，均可减轻稻瘟病的病情，其防治效果在44％－55％。