吉安市水稻黑条矮缩病的发生情况和原因分析

2007年吉安市水稻二晚发生较多矮化、不结实现象,从症状上诊断为水稻黑条矮缩病。该病自1997年开始在该市发生,至2006年发生都比较轻,今年突增。该病最大的症状特点是在叶片和茎杆上产生蜡白色至黑褐色点条状隆起。不同水稻品种对该病的抗性差异大,丰源优299、丰优210、金优2067等感病品种发病重。今年发生重的原因主要是去年暖冬,今年7、8月份干旱,插花田多等。     

水稻品种穗颈瘟抗性试验

通过对10个水稻品种3年的试验观察,Q优6号和T优618品种穗颈瘟发病率均在60%以上,不宜继续在麻江县推广种植;其他品种可以继续推广,但中优177、科优21、T优6135品种穗颈瘟平均发病率均高于麻江县常年种植的大糯品种,种植时应做好稻瘟病的防治工作。湘优109、金优T16、中优808、遵优3号、内5优39等品种可在麻江县推广使用。     

6个不同水稻品种对异丙甲草胺的敏感性差异

为探究水稻对异丙甲草胺的敏感性,选育耐药性品种及为异丙甲草胺水田安全应用提供理论依据,用琼脂培养法室内测定了‘T优15’、‘株712s’、‘深两优5814’、‘T优227’、‘湘丰优9号’、‘丰源优272’等6个水稻品种对异丙甲草胺的敏感性。结果表明,异丙甲草胺对水稻发芽、苗与根的生长均有较强的抑制作用,异丙甲草胺浓度越高抑制作用越大。并且根比苗更为敏感,在异丙甲草胺浓度为0.05mg/L时,6个品种根长抑制率分别为38.7%、34.2%、28.4%、16.1%、16.4%、25.1%,苗高抑制率分别为7.6%、6.3%、8.2%、8.9%、18.3%、5.5%。6个水稻品种中,‘丰源优272’对异丙甲草胺耐受性最高,异丙甲草胺对其苗高、苗重、根长、根重的IC50分别为0.958 9、1.867 4、1.093 9、3.968 2mg/L。     

水稻品种(组合)抗病虫性的评价

在杭州对8T62、87品6、中育88-9 3个中籼品种及汕优63、Ⅱ优46两个杂交组合作了抗稻瘟病、白叶枯病、纹枯病、白背飞虱、褐飞虱、稻纵卷叶螟和二化螟等3病4虫的抗性鉴定,并进行了农艺性状观察和产量测定。结果表明,8T62、Ⅱ优46、中育88—9综合抗性较好,而Ⅱ优46较感白背飞虱,汕优63高感白叶枯病。     

惠水县优质稻主要病虫害发生规律及控制技术

惠水县从2002年开始实施优质稻的生产。至2004年的3a间，累计种植优质稻2万hm^2。2004年优质稻种植1．03万hm^2，占水稻总面积的81．5％，种植的优质稻品种为：协优63号、K优047、K优5号、D优527、新香优63、金优桂99、两优363、金优63、金优527等。3a来，为促进优质稻米的开发生产，确保优质稻生产丰收，植保站参照《贵州省无公害优质稻米生产技术规范》DB 52/T 444—2003，     

不同早稻品种对纹枯病的抗性测定

为筛选适宜在大冶市生态环境条件下栽培的高抗、优质、高产的早稻当家品种，从2001年开始，对引种的优质早稻品种进行纹枯病抗性测定。结果表明，协优402发病最轻，抗性排名第1；其次是株两优02和金优402，分别排列第2和第3；发病最重是舟903。产量最高是金优402，排名第1；株两优02和金优152并列第2；协优402排名第3；产量最低是舟903。从对纹枯病的抗性和产量等综合来看，协优402、金优402和株两优402较适宜在大冶种植。     

不同水稻品种对黑条矮缩病发生的影响

田间调查及试验表明,在浙江兰溪和金华地区当前水稻主栽品种中,以汕优10 号和协优46 组合较感黑条矮缩病,病区应适当减少种植;汕优63 、协优9516 、Ⅱ优63 、协优993 等较抗病,可扩大种植。     

不同品种杂交水稻对黑条矮缩病抗(耐)病性研究

田间试验表明,供试9个杂交水稻品种对黑条矮缩病的抗性可初步分为中抗、中感、高感3个类型。其中安两优318、粤优54、富优2号为中抗,并以安两优318抗性为最强,丰产性能也好。而协优963、K优818为中感;甬优6号、甬优5号、加优99,以及协优9308为高感组合。     

水稻生物学质量和营养与二化螟危害的关系

在早晚稻的两系法杂交稻、三系法杂交稻和常规稻中各选1个品种(组合),通过测定各品种的各生物学质量指标和营养指标,研究3类型水稻品种(组合)对二化螟Chilo suppressalis (Walker)危害的影响。结果显示,二化螟的危害株率随水稻株高、外径的增加而加重;二氧化硅含量高的早稻品种和含量低的晚稻品种,二化螟危害重;还原糖和酪氨酸含量高的品种二化螟危害均重。早稻湘早籼24号、金优974和陆两优996的二化螟危害株率为0.33%、0.39%和0.72%,且随着株高的增加而增加,随着二氧化硅含量的升高而加重。晚稻湘晚籼12号、金优217和两优527的二化螟危害株率为0.42%、0.86%和1.25%,且随着外径的增加、还原糖含量和酪氨酸含量升高而增加,随着二氧化硅含量的降低而增加。表明通过水稻的生物学质量和营养指标的检测可判定水稻品种对二化螟的抗性。     

水稻新品种简介

水稻新品种简介湖北省种子管理站（４３００７０）向子钧最近由湖北省农作物品种审定委员会审定通过的６大作物１２个品种,其中包括水稻品种４个,即早稻博优湛１９,中稻Ⅱ优５０１,晚稻汕优晚３、晚稻“金优９２８”;玉米华玉４号,鄂玉９号;油菜华（油）杂４号,华...     

不同早稻品种对稻瘟病抗性研究

对16个我省主栽早稻品种进行了稻瘟病的抗性试验。结果表明,有8个品种对稻瘟病表现为很高的抗药性,6个品种表现为中抗,2个品种为感病。     

2014年上高县早稻主要病虫为害损失试验报告

本文对上高县2014年早稻纹枯病、稻瘟病、二化螟、稻纵卷叶螟和稻飞虱这几类水稻主要病虫害在防治与不防治条件下进行了田间试验对比,对不同处理病虫情况及产量情况进行调查,对防治效益进行了评估。结果表明,完全不防治产量损失最大,单一病虫害中纹枯病损失最大,其次是稻纵卷叶螟、稻飞虱、二化螟和稻瘟病;完全不防治的效益损失最大,单一病虫害中纹枯病损失效益最大,其次是稻纵卷叶螟、稻飞虱、二化螟和稻瘟病。2014年上半年雨水多,湿度大,造成纹枯病重发生,稻纵卷叶螟和稻飞虱中等发生,二化螟和稻瘟病轻发生。     

水稻条纹病毒不同地区分离物的致病性研究

 利用36个粳稻品种对来自江苏、云南、河北、山东等地的22个水稻条纹病毒(RSV)分离物进行致病性测定,根据各分离物在36个品种上的平均发病率,将参试分离物划分为HV、SH、MV、SL和LV 5个致病类型,致病力强弱为HV > SH > MV > SL > LV,其中MV和SL型占77%,表明RSV对粳稻的致病力中等偏弱。各致病型在地区间和年度间呈随机分布状态,暗示自然条件下特定地区的RSV为混合致病群。根据致病性测定结果同时将36个粳稻品种划分为免疫、抗、中抗、中感、感和高感6个抗感类型,其中中感和感病类型占70%,无高感和免疫类型,显示粳稻对RSV比较敏感但有一定程度的耐受性。根据试验结果筛选出11个具有鉴别能力的水稻品种,可对RSV分离物进行致病型鉴定。研究发现部分抗病品种对一些分离物表现为中抗~中感类型,接种量加大时可转为感病类型,由此提示各地在应用抗病品种防治水稻条纹叶枯病时应根据当地RSV致病型的差异,针对性地选用抗病品种,当灰飞虱超量发生时需及时做好治虫控病工作,并随时监测当地RSV致病型的变化,警惕品种抗性丧失。     

Rice Yellow Mottle Virus is Seed-borne but not Seed Transmitted in Rice Seeds

Seed transmission of two pathogroups of rice yellow mottle virus from Soudano-Sahelian areas of West Africa was studied in several rice genotypes. The virus was detected by enzyme-linked immunosorbent assay and the highly susceptible rice variety BG 90-2 was used for infectivity assays. In most of the rice genotypes studied (17 out of 21), rice yellow mottle virus was detected in all seed parts including glumella, endosperm and embryo at a rate ranging from 65 to 100%. Nevertheless, no seed-borne infection was found. Infectivity of the virus decreased throughout the process of seed formation suggesting inactivation of the virus as a result of seed maturation and desiccation. It was concluded that rice yellow mottle epidemics do not develop from seed-borne infections in rice seeds.     

Isolation of Microdochium oryzae and Pinatubo oryzae from Rice Seeds and their Survival on Stored Seeds

The aim of these studies was to develop a semi-selective medium to differentiate Microdochium oryzae and Pinatubo oryzae, determine the frequency of seed infection of M. oryzae, study survival of the pathogen in stored seeds, and determine the frequency of infection of seed components. To simulate epidemics of differing intensities, panicles of rice cultivars that are susceptible (IR36) and resistant (IR42 and IR46) to M. oryzae were either non-inoculated, inoculated once, twice, or three times with a conidial suspension of M. oryzae. Both M. oryzae and P. oryzae colonies were recovered from seeds and were similar in culture. A semi-selective medium developed to detect M. oryzae seed infection rates aided in differentiating M. oryzae and P. oryzae by stimulating aerial conidiogenesis of P. oryzae. The conclusions taken from these results were: (a) seeds of IR36 had higher infection of M. oryzae than of IR42 and IR46 from plants grown in the dry season, but had lower infection of M. oryzae than of IR42 and IR46 from plants grown in the wet season; (b) M. oryzae infected seeds increased with an increase in the epidemic intensity with the highest occurring after three inoculations, the least occurring with non-inoculation, and intermediate with one, or two inoculations; (c) survival of M. oryzae decreased over time in seed lots stored at 10°C and 40% relative humidity and (d) all components of the rice seeds of IR36, IR42 and IR46 lots were infected with M. oryzae with the highest frequency in the endosperm and lemma, intermediate in the basal glumes and palea, and the least in the embryo.     

水稻对白叶枯病强毒菌系Ⅴ型菌的抗性研究

作者报道了水稻对广东白叶枯病强毒菌系Ⅴ型菌抗性研究与抗源筛选评价结果。从1076份国内外水稻种质资源中筛选出29份抗病材料,占2.70％。其中IRBB7等5份具有广谱、高抗兼较好农艺性状。由日本和国际水稻所鉴定的14个抗性基因中Xa-3、xa-5、Xa-7、xa-13等抗Ⅴ型菌。抗Ⅴ型菌材料多数兼抗其它菌型,但亦有一些不抗Ⅳ型菌,表明菌型与品种间有强烈互作效应。水稻对Ⅴ型菌抗性与其类型有关,梗稻与籼稻、糯稻与粘稻、国外稻与国内稻比较,抗病率均以前者为高。     

水稻防御反应相关基因对稻瘟病菌的响应

水稻与稻瘟病菌的互作已成为研究植物与病原真菌互作的模式系统。利用RT-PCR技术检测了6个水稻品种(分别含有抗病基因Pik-s、Pita、Pit、Pi1、Pi9的近等系及回交亲本丽江新团黑谷LTH)与稻瘟病菌互作过程中多个信号相关及PR基因的表达。结果表明带有稻瘟病抗性基因Pik-s、Pita、Pit的水稻品种和LTH对稻瘟病菌#626侵染表现为亲和互作,带Pi1和Pi9的水稻品种表现为非亲和互作;稻瘟病菌接种后,亲和互作中MAPK6和MAPK12表现为上调表达,带有抗性基因Pi9的水稻品种IRBL22中BIMK2表现为上调表达。总体来看,含有不同抗病基因的水稻近等系中的PR基因对稻瘟病菌的响应较为多样,非亲和互作中在早期或早中期表现为PR基因上调表达,而亲和互作中主要在晚期上调表达,说明这些PR基因表达的时间在植物与病原互作的不同时期发挥着不同的作用。     

河南省粳稻品种抗白叶枯病鉴定及防治研究

经连续3年对豫北稻区已推广和将要推广的24个主要品种（系）进行人工剪叶接白叶枯病菌鉴定，其中中感品种7个，有郑粳754（郑稻1号）、新稻90247、郑粳756（郑稻5号）等，其余皆为感病和高感病品种。苗期移栽前3～5天喷药（叶青双或农抗751）防治白叶枯病，可使大田推迟发病10～15天。大田的防治适期应在发病的初期，喷施农药以每亩喷20％叶青双125～150克为好。农抗751（中生菌素）的效果也较理想。     

Quantification of Magnaporthe grisea During Infection of Rice Plants Using Real-Time Polymerase Chain Reaction and Northern Blot/Phosphoimaging Analyses

ABSTRACT Rice blast, caused by Magnaporthe grisea, is a serious fungal disease of rice worldwide. Currently, evaluation of the fungal pathogenicity and host resistance is mainly based on a disease rating or measurement of blast lesion number and size. However, these methods only provide visual estimation rather than accurate measurement of fungal growth in rice plants. In this study, DNA-based real-time polymerase chain reaction (PCR) and RNA-based northern blot/phosphoimaging analyses were evaluated to quantify M. grisea. Both methods were sensitive, specific, and reproducible and could accurately measure the relative growth and absolute biomass of M. grisea. The real-time PCR analysis showed that the growth of M. grisea in seedling leaves of susceptible cultivars (M201 and Wells) was approximately 46 to 80 times higher than that of a resistant cultivar (Drew) at 4 and 6 days after inoculation. The data obtained from the real-time PCR assays also were consistent with that from northern blot/ phosphoimaging analysis. However, the real-time PCR approach was much faster and more convenient in most cases. Therefore, it is an excellent tool for in planta quantification of M. grisea and can be used for reliable assessment of fungal pathogenicity and host resistance.