大螟为害小麦的初步调查

大螟(Sesamia in erens Walker)是一种以水稻为主要寄主的杂食性害虫,然而关于其为害小麦的调查研究却鲜有报道.为了研究大螟在麦田的发生规律,作者于2011年5月上、中旬,采用平行线跳跃式取样方法对安徽省部分地区麦田大螟的发生为害情况进行了初步调查.大螟以越冬代和第1代幼虫为害小麦,在小麦茎秆上蛀孔后,可取食麦茎组织,形成白穗.滁州市南谯区麦田大螟为害最为严重,田间平均受害株率达到9.83％,有虫株率为6.17％.     

一点缀螟生物学特性及其在云南德宏玉米田的为害调查

为明确一点缀螟Paralipsa gularis(Zeller)在云南省德宏州玉米田的发生情况,采用五点取样法在连片种植的夏玉米田块对一点缀螟为害情况进行调查,用随机抽样法研究其在玉米田秸秆和当年仓储的玉米果穗中越冬情况,并观察其形态特征、生活史及生物学特性。结果表明,一点缀螟在德宏州每年发生2~3代,以老熟幼虫在玉米秸秆和果穗中越冬,其中主要以第2代幼虫进行为害,玉米果穗平均被害率达24.3%。一点缀螟雌蛾体长及翅展分别为18.7 mm和30.2 mm,雄蛾分别为13.6 mm和28.2 mm;雌、雄蛾前翅外缘末端均有6个小黑点,雌蛾前翅中央有1个黑斑,雄蛾有2个黑斑;卵为散产,椭圆形,长、宽分别为0.6、0.4 mm;幼虫初为乳白色,大龄渐变为灰黑色,老熟幼虫体长25.9 mm。在室内条件下,一点缀螟的发育历期为52.5 d,其中卵期、幼虫期、蛹期、成虫期分别为7.5、26.4、10.0、8.6 d。     

大螟的转移为害规律及其测报技术探讨

通过系统调查大螟的寄主范围，明确了大螟在不同寄主植物上的转移为害规律，并将大螟的发 生分为侨居代、繁殖积累代和主害代。在明确各发生代主要虫源的基础上，提出了虫情预测的技术要点。     

苇田释放赤眼蜂时期的试验

棘禾草螟(Chilo hyrax)和芦螟(Chilo lutellus)是洞庭湖荻和芦苇的蛀茎性大害虫,尤以前者为害最大,荻、芦每年因此损失20％左右。释放赤眼蜂是防治这类害虫经济有效的方法,放蜂时期是影响田间寄生率的关键因素之一。 棘禾草螟在洞庭湖荻芦区年发生不完全3代,以幼虫越冬。各虫态发育进度参差不齐,第一代卵期拉得很长,从4月中旬至5月下旬均有螟卵,前后长达40余天。如此长的产卵期,足可利用前期在棘禾草螟卵中繁殖的成蜂,再寄生一部分末期螟卵。     

安庆郊区瓜绢螟发生规律及防治技术初探

瓜绢螟 [Diaphania indica (Saunders)],别名瓜螟、瓜野螟,属鳞翅目,螟蛾科.它是丝瓜、冬瓜、苦瓜、黄瓜、南瓜等作物上主要害虫之一.安庆郊区每年种植的瓜类蔬菜品种较多,由于菜农对该虫的发生规律不甚了解,常抓不住防治适期. 2003年瓜绢螟在本地区重发,不仅为害叶片,而且为害瓜果. 7月 29日调查 3代瓜绢螟,苦瓜百叶有虫 182头,瓜果被害率 31.5%,瓜藤被害率 5.1%,重于 2002、2004年同期调查,其百叶虫口数分别为 57、83头,瓜果被害率分别为 0及 1.2%,无瓜藤被害.严重影响了瓜果的产量和质量. 2002～2004年我们对该虫在本地的发生规律和防治措施进行了初步探索.     

浅谈来宾市2011年甘蔗螟虫严重发生原因及防治对策

甘蔗螟虫(为害甘蔗的二点螟、条螟、白螟、黄螟和大螟的统称,下同)是来宾市甘蔗生产最重要的害虫,也是我国华南、西南等地蔗区的重要害虫。由于其具有世代重叠、发生时间长、危害范围广、生产损失大等特点,是甘蔗有害生物防控的重要对象。甘蔗螟虫在来宾市一年发生4~5代。苗期为害     

玉米田外防治玉米螟的可能性

辽、吉、黑和内蒙等地区玉米螟一年1—2代,以第一代为害,对玉米产量损失最大。因此,控制第一代十分重要。一般的作法均在玉米田内进行治螟(处理越冬寄主除外)。近年来玉米的播种面积增大,如一些地区玉米种植面积占40％以上,这样给在玉米田内施用颗粒剂等措施带来了许多困难,用药量及耗资均增大。可考虑利用玉米螟成虫白天基本不在玉米田,而躲藏在附近麦田和田边高大杂草丛中的习性,消灭成虫,是值得研究的治螟途径。     

连晚秧田三化螟产卵习性观察及防治技术探讨

我区自1985年以来,三化螟为害面积逐年扩大,为害程度越来越重。全年发生三代,以第三代危害最重,损失产量最大。1987年第三代三化螟的螟害率一般田块达1.5—2.6%,严重田块高达15%以上。要控制三代三化螟的危害,重点是拆除三代的“桥梁田”,在连作稻地区,其主要虫源田是连晚秧田。据1988年统计,重螟地区的双林、南浔、织里、升山、常     

荆州市瓜绢野螟偏重发生原因及防治对策

瓜绢野螟[Diaphnia indica(Saunders)],又名瓜螟、瓜野螟。主要寄主有各种瓜类、番茄、茄子等。近年来,荆州市郊每年种植的瓜类蔬菜品种较多,面积达7333.3hm2。由于菜农未掌握瓜绢野螟的防治技术,导致每年本市黄瓜、丝瓜等作物生长后期连续遭到瓜绢野螟为害。防治不力田块,为害十分严重,对瓜类的产量和品质影响较大。1发生为害情况瓜绢野螟在本市1年发生5代。主要以老熟幼虫和蛹在瓜架干内或寄主的枯、卷叶中,表土上越冬。翌年4月底至5月初始见成虫。1代幼虫出现在5月中、下旬至6月上旬,主要为害黄瓜。2代幼虫出现在6月下旬至7月上旬,主要…     

甘蔗条螟预测方法和防治技术的改进

条螟[Procerasvenosatum(Walker)]是甘蔗生产的主要害虫之一。一般年份造成甘蔗产量损失5%～10%,个别蔗田达25%以上。甘蔗条螟的预测和防治,历来采用水稻螟虫的方法,浪费大量的人力、财力。为此,我们在调查该虫发生和为害特点的基础上,改进了预测方法和防治技术,经多年实施,该项技术的改进,每年每亩蔗田可节约预测和防治费用150～200元。现总结介绍如下:1发生为害特点1.1年发生简况该虫在厦门地区1a发生3代,各代期距60～70d,其中第三代长达220～240d。以老熟幼虫在蔗秆叶鞘内侧结茧化蛹越冬。一般年份越冬代成虫始盛期、高峰期和末期分别为…     

Roles of flavoproteins in degradation of mexacarbate in rats

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.     

祁连山老虎沟地区高寒草甸蒸散发估算

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。     

Aetiology of Rhizoctonia in sheath blight of maize in Sichuan

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.     

西北地区冬季室内三种常绿植物的光合特性比较

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。     

山西省2012年蔬菜农药残留监测结果分析

本文通过对2012年山西省蔬菜农药残留监测结果的分析,找出造成山西蔬菜农药残留问题原因,并针对性的提出了解决问题的对策,为蔬菜生产提供依据。     

环流特征量指数在新疆汛期降水趋势预测中的应用

利用中国气象局气候中心下发的74类环流特征量值,通过相关分析,建立了新疆10个区域的汛期降水预测模型。结果表明:预测模型对新疆汛期降水趋势有一定的预报能力,尤其是在新疆洪涝灾害多发的伊犁及博尔塔拉蒙古自治州、北疆沿天山一带、天山山区,建立的3个区域预测模型可以作为汛期降水预测的主要工具。     

Incidence of benomyl and iprodione resistance in isolates of Botrytis cinerea in tomato crops in England and Wales in 1986

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.     

Viruses of pepper in plastic houses in Crete

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, P_1.2 and P_1.2.3. Results of this study show that P_1.2 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, P_1,2 en P_1,2,3, worden geklassificeerd. Uit het onderzoek is gebleken dat P_1,2 de belangrijkste bedreiging vormt voor de teelt van paprika op Kreta.     

Viruses of tomato in plastic houses in Crete

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.     

辽宁省果园杂草发生情况调查

采用倒置W九点取样法调查辽宁省果园杂草,结果明确辽宁省果园杂草有24科72种,其中阔叶杂草占73.61%,禾本科占15.28%,其他杂草占11.11%;一年生杂草占80.56%,多年生杂草占19.44%。相对多度达10%以上的杂草依次为鹅观草、藜、鸭跖草、三叶鬼针草、小飞蓬、刺儿菜、铁苋菜。其中鹅观草和藜相对多度在15%以上。