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江苏省近年稻纵卷叶螟重发原因及防治对策 总被引：3，自引：1，他引：2
稻纵卷叶螟是江苏省水稻上的重要害虫.该虫在本省常年发生3代,即四(2)代、五(3)代和六(4)代.其中五(3)代及苏南沿江局部地区的六(4)代为主害代.近10年来,稻纵卷叶螟在本省持续偏重以上发生.常年发生面积超过400万hm2次,自然卷叶率50%以上,受害田块减产超过20%.特别是2003、2005、2007、2008年四(2)代至六(4)代连续大发生,发生程度历史罕见,年均发生面积超过430万hm2次,失治田块损失超过30%.分析近年来稻纵卷叶螟发生特点及持续重发的原因,提出综合防治对策,对控制稻纵卷叶螟的为害十分有益. 相似文献
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2008年资源县稻纵卷叶螟特大发生,为近10a来该虫发生最为严重的年份,第3代发生和为害面积超过水稻种植面积的90%,第4、5代连续重发。经分析认为:虫源基数大、气象条件利于迁入、田间小气候及水稻种植制度有利于其繁殖为害是2008年资源县稻纵卷叶螟重发的原因。 相似文献
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为了明确稻纵卷叶螟的田间种群动态和虫源性质,本文通过田间调查、雌蛾卵巢解剖及风场分析,对2010年江苏仪征市单季稻区第3、4代稻纵卷叶螟发生动态和田间种群的虫源性质进行系统研究.结果表明:第3代基本为迁入种群,分别在7月19-22日、26-27日、7月29-8月1日,出现3个明显的迁入峰;第4代为本地繁殖大部分迁出种群,分别在9月4日、7-9日、11日、16-17日、19-21日出现明显的蛾量突减现象.同时对迁飞高度(850 hPa)的高空风向分析表明,在这个区域内的第3代发生期间高空盛行偏南风,有利于稻纵卷叶螟的成虫从南方迁入,而第4代发生期间高空盛行偏北风,有利于稻纵卷叶螟的成虫向南回迁.第3代发生期间的降雨量、日平均气温和相对湿度对稻纵卷叶螟的大发生影响不显著,第3代(主害代)高峰日蛾量与稻纵卷叶螟的田间卵量发生程度呈显著正相关.最后讨论了近几年稻纵卷叶螟在仪征市发生为害加重的原因. 相似文献
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稻纵卷叶螟寄生性天敌的控制作用观察 总被引：1，自引：0，他引：1
稻纵卷叶螟寄生性天敌的控制作用观察郭世平，杨再学（贵州省余庆县植保站５６４４００）稻纵卷叶螟是我县水稻主要害虫之一，每年发生４～５代，以第三、四代（全国划分标准）为主害代，常年第三代幼虫在６月中、下旬为害中稻分蘖盛期；第四代幼虫７月中下旬至８月初为害... 相似文献
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稻纵卷叶螟在忻城县的早、中、晚稻上均可普遍发生,是忻城县水稻上的主要害虫之一。近年来,稻纵卷叶螟在忻城县发生为害渐趋严重,发生面积、为害程度逐年增大,特别是2008年早稻主害代第3代稻纵卷叶螟中等偏重局部大发生,发生面积4333．4ha,占种植面积76．9％,严重影响水稻生产安全。为提高今后对农业生物灾害应急防控能力和促进农业生产的可持续发展, 相似文献
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稻纵卷叶螟Cnaphalocrocis medialis Guenee是严重为害水稻的重大迁飞性害虫,历史上曾多次大发生,造成一定损失,尤以2005年2代特大发生触目惊心.稻纵卷叶螟发生规律具备迁飞性昆虫的典型特点,其大发生的表现形式通常可分为早发积累型、突降暴发型以及基数气候协同型3种形态.2016年虽为害较轻,但其发生具有一些新特点,即在成虫迁入偏早,导致累积虫量基数较大,主害代极易形成早发积累型大发生的情况下,超历史水平的超强降水反而导致成虫交配产卵困难,幼虫死亡率高,大面积实发偏轻,气候条件过犹不及,与一般年份迥然不同.现将其发生特点及发生过程与主要原因小结分析如下. 相似文献
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１９９６年稻纵卷叶螟大发生特点和原因分析许瑞秋（福建省古田县农业广播电视学校３５２２００）近年来，由于异地虫源迁入量大，当地的气候、天敌和水稻品种等生态环境因素适宜，稻纵卷叶螟发生有明显回升。１９９６年福建省古田县双季早稻和单季中稻的稻纵卷叶螟主害代... 相似文献
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2008年稻纵卷叶螟[Cnaphalocrocis medinalis（Guenée）]在盘县大发生,虫量大,范围广,为害严重,发生程度是盘县近20年来最为严重的年份。由于各级业务部门和政府高度重视,广大农户积极防治,对第四代稻纵卷叶螟的防治效果好,大面积水稻为害损失控制在3％以下,损失较小。现就2008年稻纵卷叶螟发生为害情况,进行分析总结。 相似文献
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稻纵卷叶螟绒茧蜂(Apanteles cypr-si Nixon)是稻纵卷叶螟专性单寄生天敌。为我县稻纵卷叶螟幼虫期天敌的优势种类。控制效应高而稳定:主害代(四(2)代)寄生率达10.7—70.7％,平均为28.6％。能左右稻纵卷叶螟的为害程度。为此,自198O年年开始,我站与开展稻纵卷叶螟测报同时, 相似文献
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The nature of a reductive system which actively degrades mexacarbate in the rat intestine and liver was investigated. The system is characterized by its stability against heat and protease treatments and its requirements for a flavin cofactor and an acidic pH for a maximum activity. As a result of purification and spectroscopic identification attempts the system responsible for the above reductive activity was identified to be flavoprotein. Under anerobic conditions such flavoproteinflavin cofactor systems degrade mexacarbate first to 4-N-desmethylmexacarbate and then to polar water-soluble metabolites. 相似文献
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利用祁连山老虎沟地区海拔4200m气象观测站2010年的观测资料,采用FAO Penman-Monteith公式,再利用作物系数法,对高寒草甸生长季(5月22-9月22)的蒸散发量进行估算和分析。结果发现:研究期共有124天,蒸散发总量为238.3mm,日均为1.87mm·d-1。生长初期、生长中期、生长末期的蒸散发总量依次为22.6mm,179.1mm,36.6mm,依次占研究期总量的8.4%,75.2%,15.3%。5月下旬至6月中旬,日均蒸散发量以较低水平缓慢上升;6月下旬迅速增加;6月末至7月中旬猛然回落;7月中旬至8月末,日均蒸散发量迅速上升且维持在较高水平;此后直到9月22日,缓慢减少。5-9月月蒸散发总量依次为6.6mm,46.4mm,74.5mm,77.6mm,33.1mm。 相似文献
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Aetiology of Rhizoctonia in sheath blight of maize in Sichuan 总被引：1，自引：0，他引：1
Rhizoctonia isolates obtained from maize grown in commercial fields in 33 representative counties (or cities) in Sichuan province in China were characterized according to colony morphology, hyphal anastomosis and pathogenicity. Of 141 isolates, 116 were identified as R. solani , 23 as R. zeae and two as binucleate Rhizoctonia . The isolates of R. solani were assigned to four anastomosis groups (AG): AG-1-IA (101 isolates, accounting for 71.6% of the total), AG-1-IB (2, 1.4%), AG-4 (9, 6.4%) and AG-5 (4, 2.8%). The two isolates of binucleate Rhizoctonia belonged to AG-K. On maize, isolates of AG-1-IA caused typical sheath blight symptoms. Lesions produced by isolates of AG-4, AG-5, AG-1-IB and AG-K were darker than those of AG-1-IA. Rhizoctonia zeae usually caused discontinuous lesions with a dark brown margin and a brown centre on the leaf sheaths, as well as ear rot. Isolates of AG-1-IA were the most virulent to maize, with an average lesion length of approximately 15 cm. Isolates of R. zeae produced lesions approximately 12 cm long, while those of AG-4, AG-5, AG-1-IB and AG-K were progressively shorter. On potato dextrose agar (PDA; pH 6.4), the minimum temperature for mycelial growth of R. zeae isolates was 14–18°C, the maximum 38–40°C and optimum 30°C. Isolates of R. zeae did not grow on PDA (28°C) at pH 2.0, the optimum for growth being pH 6.4. 相似文献
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西北地区冬季室内三种常绿植物的光合特性比较 总被引：1，自引：0，他引：1
使用Li-6400XT便携式气体交换系统的红蓝光源和液化CO_2钢瓶注入系统,模拟冬季室内较密闭环境下存在较高CO_2浓度且为弱光环境,设置CO_2浓度为600μmol·mol~(-1),并以400μmol·mol~(-1)作为对照组(CK),对绿萝(Scindapsus aureus)、鹅掌柴(Scheffera octophlla(Lour).Harins)和燕子掌(Crassula agenten Thunb.)进行光响应(Pn-PAR)曲线的测定。结果显示:在CO_2浓度600μmol·mol~(-1)下,三种植物的光饱和点(LSP)均比(CK)更早出现,绿萝和鹅掌柴总体的净光合速率(Pn)比(CK)高,燕子掌比(CK)低;绿萝的最大光合速率(Pmax)、光饱和点(LSP)和表观量子效率(YAQ)均最高,分别为5.62±0.145μmol·m~(-2)·s~(-1)、373.51±24.15μmol·m~(-2)·s~(-1)和0.041±0.003μmol·μmol~(-1),但暗呼吸速率(Rd)较低(-0.51±0.14μmol·m~(-2)·s~(-1));鹅掌柴和绿萝的水分利用率(WUE)和蒸腾速率(Tr),极显著高于燕子掌(P<0.01);绿萝的叶绿素SPAD值最高(70.03±4.18),极显著高于其余两种(P<0.01)。研究表明,绿萝对光照具有最强的利用能力,且能在高CO_2浓度且干旱的环境里健康生长,并能对室内环境起到较强的增湿效应,是西北地区冬季较为理想的室内植物。 相似文献
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Incidence of benomyl and iprodione resistance in isolates of Botrytis cinerea in tomato crops in England and Wales in 1986 总被引：1，自引：2，他引：1
In 1986, mass-mycelial isolates of Botrytis cinerea from 67 tomato crops in England and Wales were examined for benomyl and iprodione resistance. Of the 706 isolates obtained, 62.7% were resistant to benomyl at 2μg/ml and 43.2% were resistant to iprodione at 2 μg/ml. Iprodione resistance persisted in the absence of a dicarboximide spray programme. The incidence of benomyl resistance has not decreased since the last survey in 1984 in spite of a considerable reduction in the use of benzimidazole fungicides. There were no clear indications that the use of dichlofluanid influenced the incidence of benomyl or iprodione resistance. Disease control was poorer in crops with a higher incidence of iprodione resistance. 相似文献
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A. D. Avgelis 《European journal of plant pathology / European Foundation for Plant Pathology》1987,93(4):153-158
During a survey of virus diseases affecting pepper grown in plastic houses in Crete, during 1984–1986, tomato mosaic virus (ToMV) and tobacco mosaic virus (TMV) were detected. The most common virus was TMV, being present in samples of alle pepper cultivars carrying the L1 resistance gene, while ToMV was isolated only from susceptible pepper cultivars. According to responses ofCapsicum spp. the isolates from 640 samples checked were classified into three pathotypes: P0, P1.2 and P1.2.3. Results of this study show that P1.2 represents at present the major threat to the Cretan pepper industry.Samenvatting Bij een in de jaren 1984–1986 gehouden inventarisatie van virusziekten in paprika in plastic-foliekassen op Kreta werd zowel het tabaksmozaïekvirus (TMV) als het tomatemozaïekvirus (ToMV) aangetoond. TMV kwam zeer algemeen voor: het werd aangetroffen in alle monsters van de paprikarassen met het resistentiegen L1. ToMV werd alleen geïsoleerd uit planten van vatbare paprikarassen. Volgens de waargenomen symptomen die de isolaten van 640 monsters opCapsicum spp. vertoonden, konden de isolaten in drie pathotypen, nl. P1, P1,2 en P1,2,3, worden geklassificeerd. Uit het onderzoek is gebleken dat P1,2 de belangrijkste bedreiging vormt voor de teelt van paprika op Kreta. 相似文献
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A. D. Avgelis 《European journal of plant pathology / European Foundation for Plant Pathology》1986,92(4):147-152
Tomatoes grown in plastic houses in Crete have been inspected since 1980 for virus diseases. Plants with virus-like symptoms were checked by sap inoculation to test plants and the isolated viruses were identified by host reaction and serology. The most common viruses were, in order of frequency, tomato mosaic virus (ToMV), potato virus X, tomato bushy stunt virus (TBSV), potato virus Y and cucumber mosaic virus. The large use of ToMV-resistant cultivars reduces gradually the importance of ToMV while TBSV tends to become a serious problem of tomato in Crete.Samenvatting Van 1980–1984 werden op Kreta de in plasticfolie-kassen geteelde tomaten geïnventariseerd op de aanwezigheid van virussen. Verdachte plante werden door sapinoculatie op toetsplanten onderzocht. De daarbij geïsoleerde virussen werden daarna via de symptomen op de waardplanten en serologisch geïdentificeerd. In volgorde van belangrijkheid werden de volgende virussen het meest aangetroffen: tomatemozaïekvirus, aardappelvirus X, tomatedwerggroeivirus, aardappel Y virus en komkommermozaïekvirus, De laatste jaren is door de toenemende teelt van tomaterassen met resistentie tegen tomatemozaïekvirus het belang van dit virus sterk verminderd, terwijl het tomatedwerggroeivirus een steeds ernstiger probleem lijkt te worden. 相似文献