华北棉田二代棉铃虫发生程度中期预测

在华北棉区用扫网法和目测查虫法调查麦田一代棉铃虫幼虫发生量，用比较法和生命表分析法预测二代棉铃虫在棉田的发生程度和虫口密度。经１９９１—１９９４年应用检验，预测结果均与实际发生情况吻合。     

棉铃虫发生期积温预测法的应用

棉铃虫发生期的预测,多数地方应用期距预测法或发育历期预测法。前者需要多年而准确的历史资料,而且准确率不高,历史较短的测报站难以应用;后者因棉铃虫在土中化蛹,发育进度调查困难,若用幼虫历期推算,则因时效太长也难以测准。为了使棉铃虫发生期预测简单易行而且准确率较高,近年来,我们根据外地资料介绍,应用了积温预测法,收到了较好的效果。现谈点积温预测的体会。     

棉铃虫中长期预报技术

棉铃虫中长期预报技术赵瑗玲（湖北枝江县植保站，４４３０００）我站建站以来，棉铃虫系统测报资料至今已有３ｌ年。为了进一步提高预测预报水平，笔者将其中长期预报技术介绍如下。ｌ发生期预报我县多年来发生期预报主要采用以下几种方法：期距法、虫龄分析法、物候法及...     

一代棉铃虫成虫发生量的预测

一代棉铃虫成虫发生量的预测马光春，张平磊，赵光武，高山松（河南省新乡植保站４５３００３）棉铃虫近两年在我市暴发成灾，造成棉花减产４０％左右。准确预测棉铃虫发生量是经济防治的重要前提。经对获嘉县植保站１９８４—１９９３年用２０瓦黑光灯诱集棉铃虫成虫量的...     

用棉铃虫预报和防治指标确定棉田施药时间和防治次数

用棉铃虫预报和防治指标确定棉田施药时间和防治次数屈西峰，王建强（农业部全国植保总站，１０００２６）用棉铃虫预报和防治指标确定棉田施药时间和防治次数，一般需要在防治前２０～３０天做出预测，以便早做准备和发动群众进行防治。１两种棉铃虫防治指标及在生产应用...     

棉铃虫预报因子评述

棉铃虫预报因子评述天门市植保站李明福，张民主棉铃虫自７０年代初期大发生之后，８０年代一直发生较轻．但进人９０年代之后，发生又逐年加重，１９９４年达到了特大发生程度．根据９０年代棉铃虫的发生特点，笔者认为：在目前耕作制度条件下，在预测预报中，应重点考虑...     

切实抓好科学用药 控制第四代棉铃虫危害

切实抓好科学用药控制第四代棉铃虫危害第四代棉铃虫是我省的主害代，也是控制其为害、保住当家桃的关键时期。据省植保总站预测，今年我省第四代棉铃虫为中等偏重发生，局部大发生。为了作好这一代棉铃虫的防治，要切实抓好科学用药。１选好对口农药品种各地在选用农药品...     

用太阳黑子和自相关因子超长期预测棉铃虫的发生趋势

以太阳黑子和自相关因子为预测因子，采用逐步回归分析方法，建立了赣北棉铃虫发生趋势的超长期预测模型。该模型１９６６～１９９１年的历史符合率达８０．７７％，１９９２～１９９６年的预报确率达８０％。所建模型可以提前２ａ发出预报，据此对１９９７和１９９８年赣北棉铃虫的发生趋势进行了预测。     

河北省麦田一代棉铃虫发生调查

麦田一代棉铃虫历年来在我省发生量不大,不曾引起过人们注意。有关麦田一代棉铃虫的研究甚少,对它的发生规律也很不了解。致使预测和防治缺乏理论基础和经验。一九九二年我省麦田一代棉铃虫大发生,不仅给小麦生产造成了严重的损失,而且导致二代和三代大发生,造成全省棉花大减产,部分棉田甚至绝收。及时防治麦田一代棉铃虫,压低二代虫源基数,确保棉花生产已变得非常紧要。为尽快摸清麦田一代棉铃虫的发生规律,指导预测预报和防治。1993年对我     

棉铃虫期距的分析及其在测报中的运用

分析彭泽到1982～2000年的棉铃虫田间调查资料可知，利用二、三、四代棉铃虫上、下代产卵高峰期和盛末期之间的期距，进行其发生期的预测，其准确率较高，在实践中应用效果较好。     

转Cry1Ac/1Ab基因棉花对棉铃虫的控制效果及对甜菜夜蛾和斜纹夜蛾生长发育的影响

为评估转Cry1Ac/1Ab基因棉花对棉铃虫Helicoverpa armigera的抗性及对非靶标害虫甜菜夜蛾Spodoptera exigua和斜纹夜蛾S.litura生长发育的影响,采用室内生测法测定其对棉铃虫的抗性及对甜菜夜蛾和斜纹夜蛾不同龄期幼虫存活率、营养代谢及中肠酶活性的影响。结果表明,转Cry1Ac/1Ab基因棉花对棉铃虫第2代幼虫的抗性程度最高,幼虫校正死亡率达91.33%,但对甜菜夜蛾和斜纹夜蛾的抗性程度较低,幼虫校正死亡率分别为15.33%和13.33%。甜菜夜蛾和斜纹夜蛾各龄期幼虫取食转Cry1Ac/1Ab基因棉花后,其存活率与取食常规棉花对照无显著差异;甜菜夜蛾对转Cry1Ac/1Ab基因棉花叶片的相对取食量、近似消化率分别为16.68和93.12%,均高于取食常规棉花对照的10.72和92.00%,但差异不显著,而斜纹夜蛾取食转Cry1Ac/1Ab基因棉花后的各项营养指标均低于取食常规棉花对照,差异也不显著。取食转Cry1Ac/1Ab基因棉花后,甜菜夜蛾的过氧化物酶活性为0.02 U/mg prot,显著低于取食常规棉花的0.05 U/mg prot;斜纹夜蛾的酸性磷酸酶活性为0.15 U/mg prot,高于取食常规棉花的0.10 U/mg prot,但差异不显著,其它中肠酶活性均低于对照,亦无显著差异。     

野生植物苦皮藤种油对黄守瓜成虫防治效果的初步研究

笔者为了寻找对黄守瓜 Aulacophora femoralis chinensis(Weise)成虫的拒食、内吸活性的物质,以野生植物苦皮藤(即苦皮树、落霜红、菜药皮)Celastros angulatusMoxim 种油为主,进行了初步试验,简报如下:一、试验材料(一)供试药剂:①苦皮藤根皮粉:将苦皮藤根皮放入烘箱60℃干燥,粉碎后,通过40目筛。②苦皮藤根皮粉石油醚提取物:取上述皮粉,放入索氏脂肪提取器中用石油醚     

Sex pheromone traps as a potential means of improving control programs for the spiny bollworm,Earias insulana

Pheromone traps were reliable for detection and estimation ofEarias insulana (Boisduval) (Lepidoptera: Noctuidae) adult populations in cotton fields. Due to the aggregated distribution in traps, estimates of moth populations were more accurate at low than at high population levels. The relationship betweenE. insulana male catch and larval density could not be assessed because of the numerous chemical treatments applied to the cotton fields. However, when chemical applications were avoided, an increase in male catch was followed by an increase in larval density. SinceE. insulana eggs are difficult to detect and the larvae penetrate the cotton bolls soon after hatching and are therefore hard to control, pheromone traps are particularly useful as a warning device for potential larval infestation.

     

Effects of plant chemicals on the Cotton Bollworm,Helicoverpa armigera (Hübner): A multi-generation study

We studied the effects of feeding on different cotton cultivars with different gossypol contents on the development, reproduction and food plant utilization of three successive generations of Cotton Bollworm, Helicoverpa armigera (Hübner). Significantly higher larval survival rates were observed in three successive generations of H. armigera fed on cotton cultivar “ZMS13”compared with cultivars “M9101” and “HZ401”. There was a significant decrease in fecundity in the first generation compared with the second and third generations of cotton bollworms fed on “M9101” and “ZMS13”. Cotton bollworm generation significantly influenced mean relative growth rate, relative growth rate and relative consumption rate. The relative growth rate significantly decreased in three successive generations of H. armigera fed on the high-gossypol cultivar “M9101” compared with those fed on low-gossypol cultivar “ZMS13”. However, a significantly higher relative growth rate was recorded in the third generation than in the first generation fed on “M9101”. Measurements of development and food utilization at the individual and population levels over more than one generation ought to provide a more meaningful prediction of long-term and population dynamics of the cotton bollworm.     

Bt棉种植时期和作物布局方式对龟纹瓢虫生长发育和繁殖的影响

采集多年连作Bt棉区、Bt棉与春玉米等作物混栽区(过渡区)、多年连作果园(非Bt区)的龟纹瓢虫幼虫,分别用Bt棉上的棉蚜、Bt棉和非Bt植物上的蚜虫、非Bt植物上的蚜虫饲养,模拟研究Bt棉不同推广种植时期和作物布局方式对龟纹瓢虫发育、繁殖生物学特性的影响。结果显示,采自不同种植区域的龟纹瓢虫,雌雄成虫的体型由小到大依次为:Bt棉区<过渡区、非Bt区;体重依次为:Bt棉区、过渡区<非Bt区;幼虫历期依次为:Bt棉区>过渡区>非Bt区;新羽化的雌雄成虫体重均依次为:Bt棉区<过渡区<非Bt区;雌成虫比例依次为:Bt棉区<过渡区、非Bt区;羽化成虫的单雌产卵量依次为:Bt棉区、非Bt区<过渡区。表明采自不同种植区域的龟纹瓢虫,体型、体重、发育和繁殖特性均有较大差异,与多年连作果园和过渡区相比,多年连作的Bt棉区中,龟纹瓢虫成虫的体型和体重降低、幼虫发育历期延长、新羽化成虫的体重减轻、雌虫比例降低、单雌产卵量下降。     

苏云金杆菌乳剂防治二代棉铃虫保护天敌控制伏蚜的研究

在二代棉铃虫Heliothis armigera卵高峰期,一般年份用200倍,大发生年份用100倍苏云金杆菌(B.t.)乳剂喷雾防治效果达75%以上,可将虫口密度压低到经济损失允许水平以下。防治后调查生防田主要捕食性昆虫天敌比化防田高3倍左右,对伏蚜有较好的控制作用。伏蚜高峰期主要捕食性天敌与伏蚜之比,维持在1:200以上水平,可将防治伏蚜时间推迟10—15天,减少防治1—2次。     

部分GK系列Bt棉对棉铃虫抗性的田间评价

１９９７～１９９８年在河北省廊坊市和１９９８年在河南省新乡市分别研究了转ＣｒｙＩＡ Ｂｔ抗虫基因棉花ＧＫ－２、ＧＫ－５和ＧＫ－１２对棉铃虫的抗性水平。研究结果表明,ＧＫ－２和ＧＫ－１２在整个生育对棉铃虫皆保持极高的抗性,在对照普通棉花品种棉铃虫高峰期百株幼虫２代４４～１３８头,３代１１３～１３８头和４代１４４头密度下,对棉铃虫的控制效果分别达８８．７１％～９５．４５％、９２．７５％～９７．６５％和     

Note: A new pest,<Emphasis Type="Italic">Liriomyza trifolii</Emphasis>, on cotton in the Büyük Menderes Valley,Turkey

The study was conducted to evaluateLiriomyza trifolii (Burgess) in the cotton fields of the Büyük Menderes Valley, Turkey, from 1999 to 2000. Leaves were sampled weekly from the middle of June to the middle of August and kept in the laboratory to observe emerging leafminers. Leafminers were initially found on cotton leaves from 35 to 66 days after sowing. The numbers of larval mines varied from one to four per leaf. The largest number of infested leaves was observed in Aydın (Center), where 18.8% and 17.7% of the sampled leaves were infested in 1999 and 2000, respectively. We conclude thatL. trifolii is a potential pest in the cotton fields of Turkey and more research is needed. http://www.phytoparasitica.org posting July 3, 2003.     

Parasitoid control of the tomato fruitworm,Helicoverpa armigera,in smallholder farmer fields in Senegal

In Africa, Helicoverpa armigera (Hübner) (Lepidoptera, Noctuidae) is a key pest of cotton and vegetable crops, particularly tomato. Alternatives to insecticides to control this pest are needed such as conservation biological control. However, knowledge on the diversity and ecology of naturally occurring enemies of H. armigera is limited. A two-year field survey was conducted in a set of tomato farmer fields in the main vegetable-growing area in Senegal (Niayes) to assess the spatial and seasonal occurrence of indigenous parasitoids of H. armigera, and to evaluate the effect of insecticide use on biological control efficiency. No parasitoid emerged from H. armigera eggs. Incidence of larval parasitoids was generally moderate (20%) but highly variable (0%–100%) among fields, independently of host abundance, and negatively affected by the number of insecticide applications. Larval parasitism was largely dominated by the larval parasitoid Meteorus laphygmarum Brues (Hymenoptera, Braconidae), but a positive correlation was found between specific richness or Shannon diversity index of the parasitoid community and parasitism rate. This study is a first step toward development of research and extension programs for conservation of natural enemies in the framework of integrated management of the tomato fruitworm in Senegal.