杉梢小卷蛾寄生蜂

杉梢小卷蛾Polychrosis cunninghamiacola Lin et Pei是我省杉木林主要害虫之一。但是这种害虫有不少天敌捕食和寄生,仅寄生蜂就达13种之多。这些天敌有效地控制了杉梢小卷蛾的发生和发展,其自然寄生率很高,如第二代卵寄生率为5.8％;第三代27.3％;第四代28.5％。幼虫期第二代寄生率达1.01％;第三代5.42％(其中在一块     

北疆棉铃虫自然种群生命表的初步研究

采用作用因子构建了北疆棉铃虫自然种群生命表,并对棉铃虫种群生命表进行了研究和讨论。结果表明：由于棉田捕食性天敌的大量发生,北疆棉铃虫2代的3、4龄是关键虫期;另外, 2007年2代6龄发生期大量降雨,气温很低,空气潮湿,不利于棉铃虫幼虫的发育生长,同时茧蜂和寄蝇等寄生性天敌也大量发生,因此6龄也是关键虫期。棉铃虫3代的低龄期,由于棉田捕食性天敌草蛉、瓢虫、蜘蛛、食虫蝽的大量发生,卵至1龄为关键虫期。同时这段时期大量降雨,气温降低也不利于棉铃虫幼虫的生长。     

一熟转Bt基因棉田主要害虫及其天敌的发生规律

１９９７年在田间研究了转Ｂｔ基因棉品系Ｒ９３－４在一熟种植方式下对棉田主要害虫及其天敌及其种群的影响。结果表明,转基因棉对棉铃虫（Ｈｅｌｉｃｏｖｅｒｐａ ａｒｍｉｇｅｒａ）和棉造桥虫（Ａｎｏｍｉｓ ｆｌａｖａ）有良好的抗性,发生高期百株幼虫数量均显著低于对照品种中１２,但转基因棉田仍需防治第３和第４代棉铃虫。和常规棉相比,转基因棉自然控制田和综合防治田的棉苗蚜（Ａｐｈｉｓ ｇｏｓｓｙｐｉｉ）分别增     

棉铃虫捕食性天敌控制作用评价

在分析棉田捕生天敌数量变化及空间动态的基础上,综合考试捕食性天敌的数量、天敌与棉铃虫的空间生态位重叠度和时间发生上的同步性,建立了棉铃虫捕食性天敌控制作用的评价模型。结果表明,在棉田棉铃虫发生期,控制棉铃虫卵和初孵幼虫的天敌集团作用的大小依次为：瓢虫草蛉类〉捕食性蝽类〉蜘蛛类。天敌对棉铃虫的控制作用存在时间上的序列性和阶段性,不同棉铃虫发生世代天敌功能团和优势天敌作用大小不同。二代主要为龟纹瓢虫、     

甲胺磷对稻纵卷叶螟及其天敌的影响

实验室、田间试验表明 ,甲胺磷对稻纵卷叶螟及其寄生蜂、捕食性天敌等均有不同程度的杀伤作用。各代推迟喷药、放宽防治指标可提高纵卷叶螟幼虫被寄生率 ,对产量并无影响。结合前期施药对褐飞虱再增猖獗的促进作用 ,建议在水稻生长前期谨慎用药 ,尤其应限制甚至禁止在稻田使用甲胺磷。     

棉铃虫齿唇姬蜂生物学特性及田间控制作用研究

棉铃虫齿唇姬蜂在河南新乡棉区年发生约8代,以6个世代发生在棉田,其中4个世代与棉铃虫低龄幼虫发生期吻合。田间出现4个寄生高峰,分别在5月中旬、6月中下旬,7月底至8月初,8月底至9月初,寄生率平均在19.2～42.9％,以一、二代棉铃虫期的寄生率较高,齿唇姬蜂对3龄前棉铃虫幼虫的总寄生率平均为23.7％,最高达40.0％,占整个世代总寄生数的71.3％。该蜂是豫北棉铃虫寄生性天敌中的优势种。成蜂对菊酯类农药敏感。     

日本龟蜡蚧天敌昆虫调查简报

1978～1980年,我们通过野外调查与室内观察,对日本龟蜡蚧的天敌昆虫进行了调查,发现其寄生性天敌30多种,捕食性天敌昆虫4种。现将经鉴定的几种主要寄生蜂和瓢虫分列如下。 1.长盾金小蜂一年发生2代,以初孵幼虫在雌蚧腹下越冬。越冬代寄生率一般为10％左右,第一代寄生率可达50％以上。     

棉铃虫天敌——齿唇姬蜂生物学观察

齿唇姬蜂Campoletis Chlorideae Uchida属膜翅目姬蜂科。该蜂能寄生鳞翅目夜蛾科的部分害虫,主要寄生低龄棉铃虫幼虫。近三年来,我们在棉虫综合防治的同时,重点对齿唇姬蜂进行了调查、饲养、接种繁殖,发现齿唇姬蜂,在棉田的自然寄生率较高,是棉铃虫主要天敌之一,现将该蜂饲养观察的结果简述于后。     

用人造卵繁殖的螟黄赤眼蜂防治棉铃虫研究

１９９４～１９９５年在山东省用人造卵繁殖螟黄赤眼蜂，进行防治棉铃虫的研究。人造卵的寄生率为９１．１４％，出蜂率为８９．６８％，每张卵卡有人造卵１４０粒，可出蜂３０００头。冷藏虫态以前蛹期为宜，冷藏１５和２０天，出蜂率分别为８７．２６％和８２．８１％。人造卵出蜂比较集中，２天内可基本出完。成蜂饲喂蜂蜜可显著延长寿命。纸袋出蜂器出蜂率可达９１．８３％～９９．０９％。棉田释放人造卵蜂防治第２代棉铃虫，１９９５年寄生率为８０．３１％，最高达９３．７５％，防治效果稍好于施药区。防治第３代棉铃虫的效果较低，寄生率仅有４２．９７％，原因与蜂卡冷藏时间长以及高温多雨有关。放蜂区捕食性天敌数量比施药区高４．０３～９．３６倍，对棉蚜、棉叶螨有较好的控制作用，一般不需防治。     

应用赤眼蜂携带病毒防治棉铃虫的初步研究

利用赤眼蜂携带棉铃虫NPV病毒防治第2、3、4代棉铃虫，以万灵、甲胺磷化学杀虫剂防治作对照。结果显示：赤眼蜂对棉铃虫卵的寄生率平均为33.3%，最高达37.3%；棉铃虫幼虫病毒感染死亡率为61.3%到70.6%；赤眼蜂带病毒防治田天敌数量、种类明显多于化学杀虫剂防治田，标虫、蜘蛛、小花蝽平均百姝数量比化学杀虫剂防治田分别高83.6％、100.8%、69.2%，在赤眼蜂带病毒防治田存在的草蛉、蜡蝽等捕食性天敌的化学杀虫剂防治田未发现：赤眼蜂带病毒防治田平均虫口减退率为66.19%，化学杀虫剂防治田为70.25%，差异不显著（p=0.05）；眼眼蜂带病毒防治田棉花的平均花蕾虫害率为35.97%与化学杀虫剂防治田的34.93%差异也不显著（p=0.05）。     

Hymenopteran Parasitoids on Fruit-infesting Tephritidae (Diptera) in Latin America and the Southern United States: Diversity, Distribution, Taxonomic Status and their use in Fruit Fly Biological Control

We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.     

Brief Guide for Authors

正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad     

The parasitoid complex ofLiriomyza cicerina on chickpea (Cicer arietinum)

Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.     

Plant–herbivore asynchrony necessitates augmentative releases of the exotic beetle,Zygogramma bicolorata,to enhance the biological control of P arthenium hysterophorus

Systematic information on the quantitative impact of Z ygogramma bicolorata on the biology of P arthenium hysterophorus is crucial as the seeds of this weed continue to germinate from the accumulated soil seed bank throughout the year in the form of different germinating flushes, while the activity of the beetle ceases during winter as it enters diapause. Therefore, plant–herbivore interactions need to be explored to develop predictions of the overall impact of the introduced beetle on the weed. The findings revealed that defoliation by Z . bicolorata had a significant impact on the plant height, density and flower production in flushes F ₃, F ₄ and F ₅, but not in F ₁ and F ₂ that exhibited longer periodicity, profuse branching, a longer flowering period and maximum flower production and contributed mostly to the existing seed soil bank. Therefore, total depletion of the existing soil seed bank was not possible. Consequently, the effect of augmentative field releases of laboratory‐reared beetles was explored on F ₁ and F ₂ in February for three consecutive years (2011–2013). Before initiating the trial, random soil samples were taken from the plots that were assigned to the paired treatments (i.e. with the beetle and without the beetle [insecticide‐treated]) and it was found that the seed bank in those samples did not differ. The single release of Z . bicolorata adults at five per plant at the six‐leaf stage significantly reduced the soil seed bank, compared to without the biocontrol agent, irrespective of the flushes at the end of the season.     

Effects of the saprophytic leaf mycoflora on growth and productivity of winter wheat

The effects of the saprophytic mycoflora and its interference with cereal aphids on growth and yield of winter and spring wheat was studied in field experiments in 1980, 1981 and 1982.Yields varied between 5000 and 8000 kg dry matter of kernels per ha. The effect of the saprophytic mycoflora on yield was determined in different treatments: A) no control measures against cereal aphids and saprophytic and necrotrophic fungi, B) no control of cereal aphids, control of saprophytic and necrotrophic fungi, C) control of cereal aphids and control of saprophytic and necrotrophic fungi, D) control of cereal aphids and stimulation of saprophytic mycoflora and E) control of cereal aphids, no control of saprophytic and necrotrophic fungi nor stimulation of saprophytic mycoflora.Considerable differences in top densities of saprophytic mycoflora (10 times as large in A and D as in B and C) were determined. The consequences of these differences for the growth and productivity of wheat were minor. A negative effect of saprophytic mycoflora on the yield could not be detected in 1981 and 1982, whereas a small positive significant effect was found in 1980. This stimulation may have been due to competition between necrotrophic fungal pathogens and saprophytic mycoflora. As a result of favourable weather conditions necrotrophic fungal pathogens were very numerous in 1980 and could form an important yield reducing factor. Yield levels may effect the importance of the necrotrophic and saprophytic mycoflora as yield reducing factors. Additionally, in the presence of aphid honeydew captafol was found to be relatively ineffective against saprophytic fungi.     

Relationship Between Production of the Phytotoxin Prehelminthosporol and Virulence in Isolates of the Plant Pathogenic Fungus Bipolaris sorokiniana

A gas chromatographic method was developed to quantify the phytotoxin prehelminthosporol, which is a sesquiterpene metabolite of the plant pathogen Bipolaris sorokiniana. The toxin was extracted from mycelium or culture filtrates, pre-cleaned using solid phase extraction, and analyzed by gas chromatography as a trimethylsilyl-derivative. The detection limit of the method was 5ngl^–1 (signal to noise ratio 4:1) which corresponds to ca. 15ng prehelminthosporol per mg dry weight of mycelium or 15ng prehelminthosporol per ml culture filtrate. The total amount of prehelminthosporol (mycelium plus culture filtrate) increased with cultivation time when examined in six isolates of B. sorokiniana after 6, 9, 12 and 15 days of incubation. The screening experiment of 17 isolates for prehelminthosporol production after 8 days of incubation revealed significant differences in the toxin production between the isolates. The isolates with low toxin production had lower virulence towards barley roots compared to those with higher production of the toxin. However, the virulence did not increase with prehelminthosporol level among the high producing isolates. Prehelminthosporol was also analyzed in a number of related Bipolaris and Drechslera species. In addition to B. sorokiniana, three out of six Bipolaris species (B. setariae, B. zeicola, B. victoriae) produced prehelminthosporol, which indicates that ability to produce prehelminthosporol is conserved among closely-related Bipolaris species.     

Effect of botanical insecticides and bacterial toxins on the gut enzyme of the rice leaffolderCnaphalocrocis medinalis

The effect of botanical insecticides and bacterial toxins on gut enzyme activity of larvae of the rice leaffolderCnaphalocrocis medinalis (Guenée) (Insecta: Lepidoptera: Pyralidae) was investigated. Gut enzyme activities were affected by botanical insecticides and bacterial toxin individually and in combination. When fed a diet of rice leaves treated with botanical insecticides and bacterial toxins, in bioassays the activities of gut tissue enzymes — acid phosphatases (ACP), alkaline phosphatases (ALP) and adenosine triphosphatases (ATPase) — of rice leaffolder larvae were affected. When combined, the effect was more severe at a low concentration. Larvae that were chronically exposed to botanical insecticides and bacterial toxins showed a reduction in weight (59–89%) and exhibited a significant reduction in ACP, ALP and ATPase activities. The combination ofBacillus thuringiensis kurstaki and botanical insecticides caused a decrease of twofold in enzyme activity even at reduced concentration. A synergistic effect was found when botanical insecticides and bacterial toxins were combined at low doses. These effects were most pronounced in early instars. Clear dose-response relationships were established with respect to enzyme activity. In conclusion: (i) biopesticides are relatively safe and biodegradable; (ii) a synergistic effect of botanical insecticides and bacterial toxins was found; (iii) less expensive, readily available and naturally occurring biopesticides could be an alternative for organic and inorganic pesticides in controlling RLF. http://www.phytoparasitica.org posting Sept. 28, 2004.