中国水稻近等基因系在黑龙江省稻瘟病菌生理小种中的应用研究

为了寻找适应于黑龙江省稻瘟病菌生理小种研究的鉴别品种,首次将中国水稻近等基因系应用于黑龙江省稻瘟病菌生理小种监测研究中,采用中国第一套7个鉴别品种对生理小种的鉴别力与其进行比较分析,证明中国水稻近等基因系具有较强的鉴别能力,对同一中国小种具有细划作用,适宜黑龙江省稻区稻瘟病菌生理小种鉴定研究。     

中国小麦条锈菌条中34号的发现及其致病特性

小麦条锈菌贵农22致病类型9(简称G22-9)2009年首次在四川省仪陇县的小麦品种川麦42上检测到,目前已扩展至全国9省65县(市、区)。其出现频率从2009年的0.11%逐年上升至2015年的10.56%。从其毒性基因谱、对生产品种的致病性以及近年来的出现频率和分布范围衡量,预测其在今后一段时间内将成为我国小麦条锈菌的主要优势小种。2016年经全国小麦锈病和白粉病研究协作组会商决定,将G22-9致病类型正式命名为条中34号。条中34号小种的出现和近年来的持续发展对我国小麦条锈病的发生流行以及抗病育种产生重要影响,对小麦安全生产构成一定威胁。今后应加强对该小种动态监测和抗病育种的预见性,及早调整品种布局,采取作物结构调整和药剂包衣(或拌种)等预防与控制措施,降低病害流行风险,保障小麦生产安全。     

Characterization,genetic diversity and distribution of Xanthomonas campestris pv. campestris races causing black rot disease in cruciferous crops of India

Black rot, caused by Xanthomonas campestris pv. campestris (Xcc) is a disease of crucifer crops. The objective of this study was to characterize races of Xcc, their distribution and genetic diversity in India. Two hundred and seventeen isolates of bacteria were obtained from 12 different black rot‐infected crucifer crops from 19 states of India; these were identified as Xcc based on morphology, hrpF gene and 16S rRNA gene based molecular markers and pathogenicity tests. Characterization of races was performed by using a set of seven differential crucifer hosts, comprising two cultivars of turnip (Brassica rapa var. rapa) and cultivars of Indian mustard (B. juncea), Ethiopian mustard (B. carinata), rapeseed mustard (B. napus), cauliflower (B. oleracea) and Savoy cabbage (B. oleracea var. sabauda). Races 1, 4 and 6 of Xcc were identified and, among these races, race 1 followed by race 4 dominated most of the states of India. Genetic diversity of the Indian isolates of Xcc was analysed using repetitive sequence‐based PCR (rep‐PCR) including primers for REP (repetitive extragenic palindromic), ERIC (enterobacterial repetitive intergenic consensus) and BOX (amplifying with BOX A1 R primer) repetitive elements. This method of fingerprinting grouped the isolates into 56 different DNA types (clusters) with a 75% similarity coefficient. Among these clusters, DNA types 22 and 53 contained two different races 1 and 4, whereas DNA type 12 contained races 1, 4 and 6. However, no clear relationship was observed between fingerprints and races, hosts or geographical origin.     

大豆疫霉根腐病病原学的研究

详述了大豆疫霉根腐病的病原生物学、病原生理小种分化等方面的研究进展和取得的新成果,并对其中的一些研究进行了评述和展望。     

不同品系对小麦白粉病的抗性鉴定

通过田间自然发病和人工接种鉴定，对2000年华北北部203份材料中选育出来的抗病性、丰产性好的48份材料再次进行成株期和苗期抗白粉病鉴定，鉴定结果：成株期免疫材料有24份，高抗材料9份，中抗材料6份。苗期无免疫材料，高抗材料31份，中抗材料10份。     

稻瘟病菌生理小种RAPD分析及其与马唐瘟的差异

氯化卞法微量提取稻瘟病菌７个生理小各和马唐瘟病菌基因组ＤＮＡ，用６０个随机引物进行ＰＣＲ扩增，其中２１个引物的特异性扩增条带，第一引物－菌系组合扩增到３－１９条，平均１０．３条；其中有多态性条速为１－１２条，平均６．１条，多态性为６１．１％。说明稻瘟病菌群体有丰富的ＲＡＰＤ多态性。引物ＯＰＨ１、ＯＰＨ２，ＯＰＨ４，ＯＰＨ１３，ＯＰＨ１４，ＯＰＫ１４等扩增的条带多，多态性丰富，而且可以有效地区分稻瘟     

黑龙江省大豆灰斑病生理小种监测及主栽品种抗性分析

为明确黑龙江省不同地区大豆灰斑病菌生理小种出现频率及类型,采用自行筛选的鉴别寄主对采自17个不同大豆产区的30份灰斑病菌进行生理小种监测鉴定.已鉴定出7个生理小种(1号、4号、6号、7号、8号、9号、11号)和4个未知生理小种.结果表明:1号生理小种仍是优势小种,出现频率为39%,较2006年下降了9%;其次是7号生理小种,出现频率为28%,较2006年上升了7%.对黑龙江省56份主栽品种进行抗病性鉴定,鉴定出高抗品种4个,垦丰16号、垦丰18号、绥农22号、绥农25号,抗病品种14个.     

河北省西瓜枯萎病菌生理小种分化及其分布

采用国际公认的鉴别寄主Sugar Baby、Charleston Gray和Calhoun Gray的病株率作为抗性分级标准,对采集于河北省西瓜种植区46个县（市）的西瓜枯萎病菌系进行了致病性测定。根据鉴别寄主对供试菌系的抗感反应,将46个西瓜枯萎病菌系划分为0号、1号和2号3个不同的生理小种,分别包括8,30和8个菌系,占供试菌系的17.4%、65.2%和17.4%;0号生理小种菌系致病性最弱,仅使品种Sugar Baby感病,以冀中和冀南居多;1号生理小种菌系致病力中等,使鉴别寄主Sugar Baby和Charleston Gray感病,而使Calhoun Gray抗病,分布在整个河北省西瓜种植区;2号生理小种的菌系致病力最强,使3个鉴别寄主均能感病,主要分布在冀中和冀北。     

PCR detection of Fusarium oxysporum f.sp. gladioli race 1, causal agent of Gladiolus yellows disease, from infected corms

Fusarium oxysporum f.sp. gladioli (FOG) race 1 infects both large- and small-flowered Gladiolus cultivars. Race 2 isolates infect only small-flowered cultivars but can be present as epiphytes on large-flowered plants. When 160 arbitrary 10-mer oligonucleotide primers were tested on FOG by PCR to find RAPD markers specific for race 1, the RAPD primer G12 amplified two discriminating DNA fragments, AB (609 bp) and EF (1196 bp), in race 1 isolates only. Both fragments were cloned and sequenced. Two pairs of race 1-specific primers for multiplex PCR were designed. Tests of 112 F. oxysporum isolates by PCR showed that, in almost all cases, race 1 isolates of vegetative compatibility group 0340 could be distinguished with these primers. Seven putative race 1 isolates did not react in multiplex PCR; hybridization studies with labelled AB and EF DNA fragments showed that these isolates belong to separate groups. A bioassay was developed to detect corms that were latently infected with FOG race 1. Gladiolus corms were homogenized and incubated for 5 days at 28°C in a semiselective medium to induce growth of Fusarium . Cultivated mycelium was isolated and subjected to the developed multiplex PCR after standard DNA isolation or disruption by microwave treatment.