Transfer of the β‐tubulin gene of Botrytis cinerea with resistance to carbendazim into Fusarium graminearum

BACKGROUND: Resistance to carbendazim and other benzimidazole fungicides in Botrytis cinerea (Pers. ex Fr.) and most other fungi is usually conferred by mutation(s) in a single chromosomal β‐tubulin gene, often with several allelic mutations. In Fusarium graminearum Schwade, however, carbendazim resistance is not associated with a mutation in the corresponding β‐tubulin gene. RESULTS: The β‐tubulin gene conferring carbendazim resistance in B. cinerea was cloned and connected with two homologous arms of the β‐tubulin gene of F. graminearum by using a double‐joint polymerase chain reaction (PCR). This fragment was transferred into F. graminearum via homologous double crossover at the site where the β‐tubulin gene of F. graminearum is normally located (the β‐tubulin gene of F. graminearum had been deleted). The transformants were confirmed and tested for their sensitivity to carbendazim. CONCLUSION: The β‐tubulin gene conferring carbendazim resistance in B. cinerea could not express this resistance in F. graminearum, as transformants were still very sensitive to carbendazim. Copyright © 2010 Society of Chemical Industry     

小麦玉蜀黍赤霉的比较研究

用墨西哥、斯里兰卡、印度尼西亚和中国的玉蜀黍赤霉[Gibberella zeae (Schw.)Petch]对42个中国品种和116个墨西哥品种麦穗进行接种。两年结果说明,墨西哥和中国菌株间致病力的差异显著。中国菌株的致病力最强,墨西哥菌株最弱,印度尼西亚菌株与斯里兰卡菌株介于两者之间。因此,在不同病害流行区可能存在不同的生态型。此外,国内外菌株的培养性状也有相应的差异。     

我国改良小麦品种抗赤霉病性的来源与抗赤霉病性改良中的问题

 从3万多份小麦材料的抗赤霉病性鉴定及主要抗赤霉病品种的系谱分析中发现，我国改良小麦品种的抗赤性最初起源于中度感病品种。其中，最主要的是一些中度感病的意大利品种和我国地方品种。70年代以来，抗赤性来源几乎局限于意大利品种Mentana、Funo和我国地方品种台湾小麦等几个基因型，以致80年代我国抗赤育种没有取得新的突破。因些，很有必要广泛开拓和利用新抗源。抗赤性的选择应当在低世代和人工诱发病害流行的条件下进行，把抗赤性分为O、HR、R、MR、LR、S和HS更合理。     

13种杀菌剂对水稻细菌性基腐病菌的室内毒力测定

 采用含毒介质法,测定了13种杀菌剂对水稻细菌性基腐病病菌的室内毒力。结果表明：20%亿达枯荣抑菌效果最好,最低有效抑菌浓度为29.00μg/mL;其次是90%瓜爽和72%农用链霉素,最低有效抑菌浓度分别为47.50μg/mL和54.00μg/mL;75%百菌清、枯必治、80%杀菌狂、70%代森锰锌、50%万竞生和77%可杀得,最低有效抑菌浓度为156.50～706.00μg/mL;50%氟吗霜疫克和15％庄园乐水剂最低抑菌浓度均为1125μg/mL;20%叶枯唑抑菌效果较差,最低抑菌浓度为3000.00 μg/mL;80％烟病速克净的抑菌效果最差,抑菌最低有效浓度高达6000.00 μg/mL。     

首次发现巴西果胶杆菌(Pectobacterium brasiliense)引起甘薯茎腐病

<正>Dickeya和Pectobacterium属细菌的植物寄主广泛,包括十字花科、茄科、百合科、伞形花科和禾本科等科的农作物^[1],所引发的细菌性软腐病严重影响农作物的产量和品质,造成严重经济损失,威胁农业生产和粮食安全。Dickeya和Pectobacterium属不同种的菌株能侵染同一种植物,产生相似的病症。如已发现能侵染马铃薯并导致软腐病害的有D. solani、D. dianthicola、D. dadantii、D.chrysanthemi、D. zeae、P. versatile、P. carotovorum、P. brasiliense、P. atrosepticum、P. betavasculorum、P. parmentieri、P. parvum、P. peruviense、P. polaris、P. actinidiae和P. punjabense等种的细菌^[2-3]。     

小麦品种对赤霉病抗扩展性的稳定性研究

1982—1987连续5年,每年分3个播期,对23个小麦品种(品系)进行定位小花注滴接种菌液诱发赤霉病,统计其发病小穗数,利用 Tai G.C.C.(1971)所提出的分析方法,估测和分析了各种供试品种(品系)对赤霉病抗扩展性的稳定性参数,并研究了其中6个抗性不同的品种(品系)病小穗扩展的进程。其结果:(1)环境对品种感染赤霉病有较大影响,但品     

Genetic variation and covariation for aggressiveness, deoxynivalenol production and fungal colonization among progeny of Gibberella zeae in wheat

Gibberella zeae (anamorph Fusarium graminearum ) causes head blight of cereals and contaminates grains with mycotoxins such as deoxynivalenol (DON). To determine the correlations among aggressiveness traits, fungal colonization and DON production, 50 progeny from a segregating population of G. zeae were inoculated onto a susceptible winter wheat cultivar in three field environments (year–location combinations). Aggressiveness traits were measured as head-blight rating and plot yield relative to noninoculated plots. Fungal colonization, measured as Fusarium exoantigen (ExAg) content, and DON production were analysed with two ELISA formats. Disease severity was moderate to high based on head-blight rating and relative plot yield. Fusarium ExAg content and DON production ranged from 0·26–1·41 units and from 4·18–43·70 mg kg⁻¹, respectively. Significant ( P  = 0·01) genotypic variation was found for all traits. Heritability for Fusarium ExAg content was rather low because of high progeny–environment interaction and error. DON/ Fusarium ExAg ratio did not vary significantly ( P  > 0·1) among progeny. Correlation between DON production and Fusarium ExAg content across environments was high ( r  = 0·8, P  = 0·01), but no covariation existed between aggressiveness traits and DON/ Fusarium ExAg content ratio.     

水稻基腐细菌Tn5插入突变体库的构建及其致病相关突变体的筛选

采用转座子Tn5插入突变技术,共获得5 261个接合子。通过马铃薯软腐快速筛选和PCR检测验证,获得267个使马铃薯软腐能力丧失或下降的Tn5插入突变体,并测定其在水稻上的致病力和烟草上的过敏性坏死反应(HR)。结果表明:在267个突变体菌株中,对水稻无致病力的有71个,其中在烟草上无HR反应的有59个,产生HR反应的有12个;对水稻致病力下降的有68个,其余突变体菌株对水稻致病力与野生菌株差异不明显。另外,267个突变体菌株中有146个无HR反应,其中有90个对水稻无致病力或者致病力下降。致病力的分析结果表明,获得的突变体是由Tn5插入Dickeya zeae染色体上不同的致病相关基因位点导致的。     

小麦地方品种望水白抗赤霉病性的遗传分析

本文应用常规分析法研究了抗病品种望水白与感病品种中国春正反交F_1代赤霉病病小穗率的差异,用联合尺度测验分析了该组合的P_1、P_2、F_1、F_2、B_1和B_2世代抗赤霉病性的遗传模式及基因效应,估算了抗赤霉病性的基因数目。并用单体分析对望水白的抗扩展基因进行了染色体定位。全部抗性鉴定的材料采用田间剪颖滴菌接种,鉴定其抗赤霉病性,单体分析的F_2代还用了离体水培单花注射接种法。结果表明:小麦品种的抗赤霉病性是受细胞核基因控制的数量性状,有5-6对基因控制望水自的抗扩展性,分别定位在4A、5A、7A、7B和4D5条染色体上。2D染色体上的基因的作用还有待于进一步研究。望水白与苏麦3号属于不同的赤霉病抗源。     

对丝黑穗病不同抗性的玉米自交系的遗传多样性研究

采用RAPD标记,将33份对玉米丝黑穗病有不同抗性的普通玉米骨干自交系分为5个类群,RAPD标记划分的结果与传统的遗传系谱不完全一致,但与杂种优势利用的结果相符,生产上优良的杂交组合无一出现在类群内;18个抗病或中抗系分散于5个类群中,依据杂种优势利用的原理,可用类群内的抗病系改良类群内的感病系选育优良的抗病系。