2007年吉林省玉米主要病害调查及其发生趋势预测

The August to September 2007,researched and collected the stylebook of main corn diseases of the districts in Jilin province including Changchun,Siping,Yanbian,Baicheng etc.The research showed that northern corn leaf blight and gray leaf spot occurred in large in Jilin province.Partly corn production-areas of Baicheng and Songyuan district northern corn leaf blight occurrence reached 100%,and gray leaf spot reached 90%,and will probably grew up main corn diseases years in the future.Some areas eyespot,maize stalk rot,corn sheath blight,common smut,southern corn leaf blight,heat smut,etc,will occur also widely,and even grew up the main corn disease in some corn production-areas in this year.     

不同玉米自交系对小斑病和灰斑病的抗性分析

The results of the experiment expressed the disease resistance was that the different corn inbred lines on the southern leaf blight and corn gray leaf spot existed certain difference.The better resisting diseases inbred lines to the southern leaf blight include 308,Liao122 and Xun92-6.The better resisting diseases inbred lines to corn gray leaf spot include H21,478 and Xun92-6.The better resisting diseases inbred lines to the southern leaf blight and corn gray leaf spot include Xun92-6,308 and 478.     

Rice diseases in China

According to incomplete records, there are about 50 fungus diseases of rice in China.Rice blast and sheath blight are the most destructive and cause severe damage. Other fungus diseases, such as rot, narrow brown leaf spot, leaf scald and brown spot are not serious. Four bacterial diseases of rice occur in China. Bacterial blight is the most common and destructive one, followed by bacterial leaf streak, rice brown spot and brown stripe.The latter two appear sporadically and are less important. The virus and virus-like diseases of rice that have been recorded in China are rice yellow dwarf, rice dwarf, rice yellow stunt, rice black-streaked dwarf, rice stripe, dwarf-like diseases, rice orange leaf disease, rice transitory yellowing, and grassy stunt etc. They are distributed mainly in the southern part of China beyond the Yangtze River. Rice yellow stunt virus has recently become important and widespread in China. It causes 20-30% of yield losses in areas where it prevails.     

Ustilaginoidea virens: A Fungus Infects Rice Flower and Threats World Rice Production

Rice false smut disease, which is caused by the fungus Ustilaginoidea virens, is currently one of the most devastating rice fungal diseases in the world. Rice false smut disease not only causes severe yield loss and grain quality reduction, but also threatens food safety due to its production of mycotoxins. In this review, the most recent progresses regarding the life cycle, infection processes, genome and genetic diversity, pathogenic gene and disease resistance in rice were summarized in order to provide theoretical basis for the control of U. virens. We also proposed some future directions and key questions that need to be addressed for a better understanding of the molecular mechanism that leads to rice false smut disease and the prospects for sustainable control of rice false smut.     

qRgls1.06, a major QTL conferring resistance to gray leaf spot disease in maize

Gray leaf spot(GLS)caused by Cercospora zeae-maydis and C.zeina is an extremely devastating leaf disease that limits maize production annually.The use of GLS-resistant maize hybrids is the most cost-effective approach for reducing losses.Resistance to GLS is quantitatively inherited in maize(Zea mays L.)and further sources of resistance remain to be analyzed.Here,we detected qRgls1.06,a major quantitative trait locus for GLS resistance in bin 1.06 that explained approximately 55%of the phenotype variance.Fine mapping over 2 consecutive years localized qRgls1.06 to a 2.38-Mb region.Homozygous qRgls1.06^WGR/WGR plants in DZ01 background displayed higher GLS resistance and 100-grain weight than DZ01 plants.The GLS responses of several susceptible elite inbred lines were improved by the introduction of qRgls1.06 by marker-assisted backcrossing.Our findings extend the understanding of the genetic basis of resistance to GLS and provide a set of resistant germplasm for genetic improvement of resistance to GLS in maize.     

高粱蠕孢菌叶斑病

迄今已发现的由蠕孢菌引起的高粱叶斑病,有大斑病(leaf blight)、靶斑病(target leaf spot)、叶点病(leaf spot)、小斑病(leaf spot)和枯萎病(blight of oats)等。其中以大斑病发生最广泛,危害严重,其它几种仅局部发生,危害较轻。兹以大斑病为主分述如下。     

Influence of Rice Genotypes on Folding and Spinning Behaviour of Leaffolder （Cnaphalocrocis medinalis） and Its Interaction with Leaf Damage

Folding and spinning behavior of Cnaphalocrocis medinalis （Guenee） （Lepidoptera： Pyralidae） in different categories of rice genotypes viz., resistant, susceptible, hybrid, scented, popular and wild rice genotypes were significantly different. Longer leaf selection time and folding time per primary fold; shorter primary fold and whole leaf fold; lower number of binds per primary fold and whole leaf fold were recorded in resistant and wild rice genotypes. In the correlation analysis, it was found that the leaf folding parameters were positively correlated to leaf folder damage whereas the leaf spinning parameters were negatively correlated. Similarly, the morphological characters differed significantly among the chosen genotypes and were related to leaffolder damage. The leaf width and total productive tiller number were positively correlated to leaffolder infestation. Results also indicated that the trichome density and length, leaf length and plant height might contribute to resistance whereas total number of green leaves had no effect on leaffolder infestation. In the scatter plot analysis between leaf folding and spinning characters and leaffolder damage, the genotypes were separated into four groups viz., resistant （TKM6, Ptb 33, LFR831311, Oryza rhizomatis and O. minuta）, moderately resistant （ASD16 and CORH1）, moderately susceptible （ADT36, Pusa Basmati and CB200290） and susceptible （IR36 and TN1）. The present investigation proved that the leaf morphology viz., leaf length and width, plant height and trichome density and length may play a vital role in resistance against rice leaffolder.     

Resistance Evaluation to Sheath Blight in Transgenic Rice Lines

Resistance of forty-one homozygous rice lines transformed with chitinase gene (RC24) and β-1,3 -glucanse gene (β-1,3-Glu) to sheath blight was analyzed by inoculation. Among different lines, the resistance had significant differences according to the result by cluster analysis. The lines could be categorized into resistant, moderately resistant, moderately susceptible and susceptible types, while 92.1% of which belonging to moderately resistant or moderately susceptible type. For different resistant or susceptible lines, the resistance to rice sheath blight was remarkable correlated with the chitinase activity of transgenic lines except resistant type lines, in which enzyme activity coded by target gene was lower than moderately resistant type. The chitinase activity of transgenic lines tested at different time after inoculation or different organs of the same plant was uniform, which suggested that the expression of chitinase gene was constitutive in nature. Check varieties‘ chitinase activity would change at different time after inoculation and reach a peak at sometime, but it had no difference at various parts of the same plant.     

In-vitro vs in-vivo Inoculation: Screening for Resistance of Australian Rice Genotypes Against Blast Fungus

To assist with rapid screening for rice blast resistance as a precursor in a breeding program, the susceptibility to rice blast of 13 rice genotypes from Australia was evaluated in May to June 2013 using three distinct inoculation methods(spot, filter paper and standard methods) at seedling, vegetative and reproductive stages. The results revealed that the spot and filter paper inoculation methods were successful in discerning susceptibility to the rice blast disease(P ≤ 0.05). Disease susceptibility declined significantly from the vegetative to reproductive stages. The standard method was conducted at three different stages for pot plants grown inside the mist house. However, low temperatures did not produce disease symptoms except in a few genotypes. Among the 13 rice genotypes screened, AAT9 expressed a highly resistant response, and AAT4, AAT6, AAT10, AAT11, AAT13, AAT17 and AAT18 expressed resistance at various stages. The results will be useful for selecting elite genotypes for disease tolerance where rice blast is prevalent. In addition, the resistant genotypes can serve as a gene pool used in breeding programmes to develop new resistant genotypes.     

Resistance Evaluation to Sheath Blight in Transgenic Rice Lines

Resistance of forty-one homozygous rice lines transformed with chitinase gene (RC24) and β-1,3 -glucanse gene β-1,3-Glu) to sheath blight was analyzed by inoculation. Among different lines, the resistance had significant differences according to the result by cluster analysis. The lines could be categorized into resistant, moderately resistant, moderately susceptible and susceptible types, while 92.1% of which belonging to moderately resistant or moderately susceptible type. For different resistant or susceptible lines, the resistance to rice sheath blight was remarkable correlated with the chitinase activity of transgenic lines except resistant type lines, in which enzyme activity coded by target gene was lower than moderately resistant type. The chitinase activity of transgenic lines tested at different time after inoculation or different organs of the same plant was uniform, which suggested that the expression of chitinase gene was constitutive in nature. Check varieties chitinase activity would change at different time after inoculation and reach a peak at sometime, but it had no difference at various pans of the same plant.     

玉米灰斑病的研究现状、问题与展望

玉米灰斑病是由玉蜀黍尾孢菌(Cecrosporazeae-maydis<\i> Tehon＆Daniela)引起的一种病害,最早于1924年在美国亚历山大州和伊利诺斯州发现,该病现在美国普遍发生。我国陈刚于1991年在辽宁省发现该病,至今该病在辽宁、吉林、河北等地均有发生,并已对玉米生产造成了很大的威胁。从症状、病原、流行规律、发病条件、抗源鉴定、抗性机制、抗性遗传以及防治技术等方面对该病进行了综述,同时探讨了今后玉米灰斑病的研究方向和重点。     

小麦慢病性的遗传育种研究进展

小麦白粉病和锈病是危害小麦生产的主要病害，培育抗病品种是防治小麦白粉病和锈病最经济有效且环保的方法。慢病性通过成株期延迟病菌的侵染、生长和繁殖而表现出中等抗性．较小种专化抗性持久稳定。小麦慢锈性常由2～4个基因共同作用，慢务锈和慢叶锈分别由Yr和Lr基因复合系统（Yr或Lr基因与几个加性慢病基因互作）控制；慢白粉性表现为明显的数量性状特性，在小麦染色体中，有14对染色体与慢白粉性有关。慢病性的鉴定方法和指标尚无定论。一般认为．病程曲线下面积（AUDPC）较为可靠，而倒二叶严重度可作为简易指标。CIMMYT所采用的旨在聚合微效基因以提高小麦对锈病和白粉病的持久抗性的方法值得借鉴。     

高粱种质资源抗高粱蚜鉴定与评价研究

１９９６－１９９９年在田间自然感虫和人工接虫相结合的条件下,对１２６６份高粱种质资源进行了高梁抗蚜性鉴定,筛选了９份高抗材料和２３份抗性材料,对这批材料同步进行了高粱黑穗病、高粱靶斑产现任玉米螟等抗性鉴定,筛选出了１３份抗高粱蚜瘘抗其它病虫害的双抗或多抗材料 。     

大豆资源对SMV株系抗性的鉴定

在南京田间对我国约六千份大豆资源进行大豆花叶病毒(SMV)抗性鉴定的结果,5.3％对本地区SMV毒源群体具有较佳抗性;黄淮、长江下游等地区资源的抗性优于其他地区。从国内及一些国外资源中入选的56份材料经实验室鉴定,28份具有株系专化抗性,包括7份抗S_(?)、S_c、S_(?)、S_h4个株系,3份抗3个株系,7份抗2个株系,11份抗1个株系。其中11份既具良好田间抗性又具对江苏主要株系S(?)及S_c的专化抗性,可作为本地区抗SMV育种的抗源。     

Transmission of potato leafroll virus to or from tuber slices by aphids feeding through a membrane

Summary Eye-bearing slices, cut from healthy potato tubers and placed between Parafilm membranes, were inoculated with potato leafroll virus (PLRV) byMyzus persicae. PLRV was detected by ELISA and by transmission tests in tuber slices and in plants grown from the slices of the susceptible cv. Désirée, but not in those of the resistant cv. Arkula. These results suggest that PLRV replication and transport within tuber phloem is controlled by specific mechanisms of resistance.M. persicae was also able to acquire and transmit PLRV toPl floridana from slices cut from tubers of infected plants. The aphids effectively transmitted PLRV from slices cut from the sprouting rose end but they failed to transmit it from slices cut from the heel end of tubers.     

灰飞虱对氟虫腈抗性风险评估、遗传分析及杀虫剂敏感性研究

 在室内采用稻茎浸渍法进行了灰飞虱对氟虫腈抗性风险评估、抗性遗传分析和杀虫剂的敏感性研究。于2005年采自无锡麦田的灰飞虱种群在室内饲养43代期间用氟虫腈筛选了41代,结果此灰飞虱种群的抗性从8.4倍上升到2305倍。根据Tabashnik介绍的方法计算,现实遗传力(h2)分别为0.0388(1~31代)、0.2636(32~43代)和0.1113(1~43代), 表明灰飞虱对氟虫腈具有一定的抗性风险。采用稻茎浸渍法测定了2007-2008年江苏无锡和浙江长兴两地灰飞虱种群对15种杀虫剂的敏感性, 结果表明,苯基吡唑类杀虫剂氟虫腈、丁烯氟虫腈和乙虫腈的毒力最高(LC50=0.2~1.7 mg/L),其次为烯啶虫胺、噻虫嗪、毒死蜱、吡蚜酮(LC50=1.7~9.7 mg/L),其余杀虫剂的毒力较低;按照年度间敏感性变化,发现2008年无锡灰飞虱种群对氟虫腈和乙虫腈的敏感性比2007年降低了1.1倍。近年来氟虫腈已广泛用于防治这种害虫,但乙虫腈几乎没有使用。因此,对氟虫腈敏感性降低的大田灰飞虱种群似乎对乙虫腈存在交互抗性。通过抗(R)、感(S)亲本、正反交(F1、 F1′)、自交(F2)及回交(BC)后代对氟虫腈的剂量反应研究了灰飞虱对氟虫腈的抗性遗传特性,结果表明,其抗性为常染色体的不完全显性遗传\[D(F1)=0.20, D(F1′)=0.38\],抗性由2个或2个以上等位基因控制。还对灰飞虱的抗性治理进行了讨论。     

高粱种质资源抗高粱靶斑病鉴定与评价

1996～1999年在田间人工接种诱导发病的条件下，对1476份高粱种质资源和40个高粱杂交种或杂交组合进行了抗高粱靶搬病抗性鉴定。从中鉴定筛选出419份抗高粱靶搬病的种质资源，9个高抗和7个抗高粱靶搬病的高粱杂交种或杂交组合。     

转hrf1基因水稻对稻瘟病多小种非专化的稳定抗性

以表达水稻白叶枯病菌（Xanthomonas oryzae pv. oryzae）编码harpin广谱抗性激发子的hrf1基因的转基因系为材料,在温室和田间病圃鉴定它们对稻瘟病菌的抗性,分析转基因水稻抗稻瘟病的作用机制。研究结果显示,转hrf1基因水稻对稻瘟病菌ZC3、ZD1和ZG1小种表现高抗,对ZB13表现中抗,表明hrf1基因在水稻中表达可以产生非小种专化抗性。在稻瘟病圃中对水稻稻瘟病抗性鉴定结果显示,转hrf1基因水稻在T1、T3、T5和T7代对稻瘟病菌都表现很好的抗性,表明转hrf1基因水稻对稻瘟病菌的抗性能稳定遗传。 转hrf1基因抗病水稻中防卫反应基因OsPR1a、OsPR1b、PAL和Chia4a以及正向调控水杨酸介导信号传导的NPR1基因的表达显著增强。转基因抗病水稻中硅含量显著提高。Harpin编码基因在水稻中表达,可能通过激发水稻中防卫反应基因的表达,提高水稻中硅含量等,从而使水稻产生对稻瘟病菌的广谱抗性。     

玉米抗病遗传育种的研究进展

几个遗传基础有限的玉米自交系在生产上大面积推广,而进行品种更换是玉米病害有规律发生和流行的重要原因之一。尽管我国在抗源鉴定、抗病遗传以及抗病育种的理论和实践上取得了令人瞩目的成就,在生产上玉米大斑病、玉米小斑病、玉米丝黑穗病和玉米青枯病得到控制和缓解,但是取材、育种方法、种质资源以及基础理论研究等方面的问题仍然十分突出。把长期的种质资源拓宽与近期的抗病育种工作结合起来,才能有效地防止玉米病害的发生和流行。     

156份小麦种质资源的纹枯病抗性鉴定与评价

为筛选在育种和生产上可利用的纹枯病稳定抗源,采用温室牙签接种法对156份小麦种质资源进行了纹枯病抗性鉴定。结果表明,供试材料存在纹枯病抗性差异,共筛选出36份两年表现稳定中抗及以上的种质材料,包括10份国内改良品种,16份美国引进小麦材料和10份小麦-华山新麦草后代材料。其中,Y-83-1和Y-83-3两年表现稳定抗病,且农艺性状较好,可作为抗小麦纹枯病育种的稳定抗源。