广州地区鹤顶粉蝶的生物学特性

记述了鹤顶粉蝶HebomoiaglaucippeL .各虫态的形态特征、生活史及生活习性。在广州地区 ,该蝶 1年发生 8代 ,以蛹在寄主植物上越冬 ,成虫 3月末始见 ,幼虫共 5龄 ,以白花菜科的广州槌果藤和鱼木等植物叶片为食料     

明亮长脚金龟各期形态特征

明亮长脚金龟Hoplia spectabilis Medvedev于1952年定名,一直少有其发生为害的记载,未见其详细形态学报道。2005年该虫在我国青海省天峻县布哈河流域暴发成灾。本文对当地发生的明亮长脚金龟成虫、卵、幼虫、蛹四个虫态的形态特征进行详细观察和描述,其中对雌雄成虫的区别特征、雄性外生殖器特征、幼虫和蛹的特征描述尚属首次,并提供了相应特征的图片,为明亮长脚金龟的鉴定识别提拱依据,是控制其暴发为害的重要基础。     

新发入侵害虫——南洋臀纹粉蚧在广州的发生情况调查

南洋臀纹粉蚧作为广州一种新近发现的外来检疫性有害生物,为掌握该虫在广州发生分布情况,为其防控提供参考依据,本文首次报道了南洋臀纹粉蚧在广州市所辖11个区的发生分布、寄主种类和相关生物学特征。调查表明,该虫在广州市各区均有零星分布,主要寄主为紫荆,在秋枫、杨梅、大花紫薇和番石榴上偶有发生,该虫在寄主树上与蚂蚁具有共生关系,其传播来源可能与宫粉紫荆种苗调运有关。调查结果为该虫制定检疫防控措施提供了依据。     

波纹杂毛虫生物学特性与防治

对波纹杂毛虫幼期形态特征作了详细描述;该虫在福建省1a发生2代,以3—4龄幼虫在地被物中越冬;系统观察了各龄幼虫的取食过程并计算了取食量。开展了室内外防治试验。为该虫综合防治提供了科学依据。     

重阳木帆锦斑蛾的生物学特性及防治

重阳木是世界上具有重要价值的树种之一,近年来重阳木帆锦斑蛾BischofiapoiycarpaCramer对其危害日益突出。该害虫在我国许多省区都有不同程度的发生,2006年在安徽省合肥地区暴发成灾。经过室外调查和室内饲养观察,分析了其暴发成灾的原因,明确了该虫的形态特征、年生活史和生活习性。该虫在合肥地区1年发生4代,有世代重叠现象。主要以幼虫在重阳木枝干的树皮、裂缝等处越冬。越冬幼虫至次年4月开始活动。在7月和8月份,以第2代和第3代幼虫危害最重。建议采用植物检疫、人工捕杀、微生物农药及化学杀虫剂等多种方法加以防治,自然天敌对其也有一定的控制作用。     

壮铗普瘿蚊的形态学与生物学习性

壮铗普瘿蚊是厦门市区出现的一种危害芒果树叶片的新害虫,现已扩散到厦门周边地区。文中对其各虫态的形态特征作了详细的描述,并对其生活史、习性进行了研究。该虫在厦门1 a发生5代,一个世代历期44-52 d。成虫在芒果嫩叶背面产卵,经2-4 d孵出幼虫后侵入叶肉并逐渐发育形成疱状突起的虫瘿,以幼虫和蛹在叶片上的虫瘿内越冬。     

一点拟灯蛾生活习性的初步观察

首次报道一点拟灯蛾AsotacaricaeBoisduval的生活习性 ,并描述其形态、寄主范围、成幼虫习性以及生活史。该虫在广州 1年发生 2代 ,以蛹在杂草、枯枝落叶以及其它缝隙等处越冬。翌年的 5月底至 6月成虫出现 ,第 1代发生在 5月底至 7月初 ,第 2代 (越冬代 )则从当年 6、7月到翌年 5月 ,幼虫 6或7龄 ,3龄前幼虫在叶背群集为害 ,4龄后分散取食。严重发生时 ,整叶被吃光 ,仅留主脉和侧脉。并提出了防治方法。     

国槐新害虫——国槐林麦蛾的研究

国槐林麦蛾是 1 998年发现的危害国槐和龙爪槐的新害虫。该虫在山东商河 1年发生 3代 ,幼虫卷缀 2～ 9个叶片或粘连花蕾在其中危害。本文首次报道了该虫幼期的形态特征、危害习性、发生与环境的关系。     

紫苏野螟的研究

本文描述了为害紫苏等药用植物的重要害虫紫苏野螟的各虫态形态特征,并对其寄主范围、为害特点、习、性、生活史以及防冶意见等作了报道。该虫在北京一年发生2～3代,以结茧幼虫在田间残株落叶或土缝内越冬。     

桉树大毛虫的生物学特性及防治

桉树大毛虫是近年在四川省会理县发现的一种石榴主要害虫。本文描述了该虫各虫态的形态特征和生物学特性。在会理县关河乡该虫一年发生1～2代,以蛹越冬。主要天敌有梳胫节腹寄蝇,对老熟幼虫的寄生率高达33～48％。人工捕杀和保护利用寄蝇是较好的防治方法。     

亚麻荠对小菜蛾幼虫取食和成虫行为反应的影响

亚麻荠是一种很少有害虫危害的油料作物。用室内生测和Y 型嗅觉仪研究了亚麻荠对小菜蛾Plutella xylostella幼虫取食和成虫行 为反应的影响。以甘蓝作对照,用亚麻荠叶片喂养的小菜蛾初孵幼虫3天后校正死亡率为79 .2%,显示了较强的致死作用;喂养小菜蛾3龄幼虫至化蛹,其存活率、化蛹率、蛹重及成 虫寿命都显著降低,表明亚麻荠对小菜蛾幼虫的生长发育有不利影响。在幼虫的取食选择实 验中,有甘蓝叶供选择时,小菜蛾幼虫不取食亚麻荠;在无可选择的情况下,小菜蛾幼虫也 取 食亚麻荠叶片,但取食量很小,与取食甘蓝叶的量相比,差异极显著。行为反应测试表明, 小菜蛾成虫对甘蓝和亚麻荠植株的挥发物都有明显的趋性反应,与对照（净化空气）相比, 差异极显著,而在甘蓝和亚麻荠之间无选择性。说明小菜蛾成虫对亚麻荠植株的挥发物具有 较强的定向反应。     

Influence of larval food consumption on the fecundity of the lacewingChrysoperla carnea

The effects of food consumption on larval growth and development and adult fecundity of the common green lacewing,Chrysoperla carnea (Stephens), were studied on two populations of larvae derived from either a laboratory colony or from field-collected adults. The number of eggs of the Mediterranean flour moth,Anagasta kuehniella (Zeller), provided to individual lacewing larvae was varied to produce three food-supply treatments: low, intermediate, and high. Food-supply was found to influence larval growth and development and adult fecundity. Lacewing larvae provided with an overabundance of moth eggs developed faster than larvae provided with fewer moth eggs than they could have consumed. Adult females that developed from the high feeding treatment had a substantially shorter preoviposition period, a later decline in egg deposition, and a significantly higher fecundity than adults arising from the other feeding classes. Unrestricted feeding by adult lacewings on an artificial diet did not compensate for prior low feeding regimes. The overall performance of the lacewings derived from the laboratory colony was substantially poorer than that of the lacewings derived from field-collected adults. This effect was accentuated when the larvae were given a low food-supply. This overall decrease in vigor is attributed to inbreeding of the laboratory culture over a one year period. These finds are relevant to mass rearing programs for this biological control agent.     

Limiting the success of stem borers (Prodoxus quinquepunctellus) in yuccas: indirect effects of ants, aphids, and fruit position

Abstract.  1. Although the moth–yucca mutualism is often studied as a pairwise interaction, yucca plants are also the sole host for a variety of other visitors. One of these additional visitors is a stem-boring moth, Prodoxus quinquepunctellus.
2. In this study, it is shown how the reproductive success of Prodoxus indirectly depends on the interactions between yuccas and their pollinators ( Tegeticula , Prodoxidae) as well as the indirect effects of ants and aphids.
3. Aggressive wood ants foraging on yuccas will attack adult Prodoxus moths while attempting to oviposit. This reduces the number of eggs laid in yucca stalks, leading to fewer larvae feeding in the stalks.
4. Once in the stalk, the survival of Prodoxus eggs/larvae depends upon the rate at which the flowering stalks dry out during fruit maturation. Portions of the stalk above the highest fruit dry out quickly and survivorship approaches zero in these dry sections, while larvae in green sections of the flowering stalk have significantly higher survival rates. The presence of aphids feeding on the stalk slows down the rate of stalk drying and could lead to increased survival of Prodoxus larvae.
5. Overall, ants have strong indirect effects on P. quinquepunctellus by controlling how many eggs are laid in the stalk and by influencing the distribution of aphids. However, it is primarily the presence and position of the fruit that can affect larval survivorship, and fruit position is a function of pollinator visits and resource limitation. These complex interactions illustrate the importance of studying the yucca–moth mutualism in a community context.     

Facilitation between invasive herbivores: hemlock woolly adelgid increases gypsy moth preference for and performance on eastern hemlock

1. Interactions between invertebrate herbivores with different feeding modes are common on long-lived woody plants. In cases where one herbivore facilitates the success of another, the consequences for their shared host plant may be severe. Eastern hemlock (Tsuga canadensis), a canopy-dominant conifer native to the eastern U.S., is currently threatened with extirpation by the invasive stylet-feeding hemlock woolly adelgid (Adelges tsugae). The effect of adelgid on invasive hemlock-feeding folivores remains unknown. 2. This study evaluated the impact of feeding by hemlock woolly adelgid on gypsy moth (Lymantria dispar) larval preference for, and performance on, eastern hemlock. To assess preference, 245 field-grown hemlocks were surveyed for gypsy moth herbivory damage and laboratory paired-choice bioassays were conducted. To assess performance, gypsy moth larvae were reared to pupation on adelgid-infested or uninfested hemlock foliage, and pupal weight, proportional weight gain, and larval period were analysed. 3. Adelgid-infested hemlocks experienced more gypsy moth herbivory than did uninfested control trees, and laboratory tests confirmed that gypsy moth larvae preferentially feed on adelgid-infested hemlock foliage. Gypsy moth larvae reared to pupation on adelgid-infested foliage gained more weight than larvae reared on uninfested control foliage. 4. These results suggest that the synergistic effect of adelgid and gypsy moth poses an additional threat to eastern hemlock that may increase extirpation risk and ecological impact throughout most of its range.     

Evaluating mulches together with Heterorhabditis zealandica (Rhabditida: Heterorhabditidae) for the control of diapausing codling moth larvae,Cydia pomonella (L.) (Lepidoptera: Tortricidae)

The potential of using an entomopathogenic nematode, Heterorhabditis zealandica Poinar, together with different test mulches (pine chips, wheat straw, pine wood shavings, blackwood and apple wood chips) to control diapausing codling moth, Cydia pomonella (L.) larvae was evaluated. Mesh cages were identified as a suitable larval-containment method. High levels of codling moth mortality were obtained when using pine wood shavings as mulch (88%) compared to pine chips, wheat straw, blackwood and apple wood chips (41–88%). Humidity (>95% RH) has to be maintained for at least 3 days to ensure nematode survival. It was also proven that nematodes had the ability to move out of infected soil into moist mulch, to infect the codling moth larvae residing at heights of up to 10 cm. Field experiments showed the importance of climatic conditions on nematode performance. Low temperatures (<15°C) recorded during the first trial resulted in low levels of control (48%), as opposed to the 67% mortality recorded during the second trial (temperatures ranged between 20 and 25°C). Low levels of persistence (<10%) were recorded in the mulches post-application. The study conclusively illustrated some of the baseline requirements fundamental to the success of entomopathogenic nematodes together with mulches for the control of codling moth.     

Estimating the susceptibility of tree species to attack by the gypsy moth, Lymantria dispar

ABSTRACT.

• 1 Numbers of gypsy moth larvae feeding on each of 922 randomly sampled trees in a Quercus—Acer—Fraxinus forest in southwestern Quebec, Canada were counted in 1979 and in 1980 to quantify the larval feeding preferences as observed in the field for eighteen deciduous and one coniferous tree species at the northern range limit of the gypsy moth.
• 2 Both the diameter at breast height (dbh) and the estimated foliage biomass of the sampled trees were used to calculate the relative proportions of foliage represented by each of the nineteen tree species in the forest canopy. With these data on availability and utilization of the tree species by the gypsy moth larvae an Ivlev-type electivity index was used to quantify the larval feeding preferences. These preferences observed in the field define the susceptibility of a tree species to attack by the gypsy moth.
• 3 The feeding preferences calculated using estimated foliage biomass were comparable to the simpler calculation based on dbh (Spearman's rho = 0.79; P= 0.0001). The dbh-based feeding preferences remained almost unchanged in 1979 and 1980 (Spearman's rho = 0.83; P= 0.0001).
• 4 The composite 1979—80, dbh-based feeding preferences show Quercus rubra, Populus grandidentata, Ostrya virginiana, Amelanchier spp. and Acer saccharum were preferentially attacked by gypsy moth. Prunus serotina, Betula lutea, Acer rubrum, A. pensylvanicum, Fraxinus americana, Ulmus rubra, P. pensylvanicum and B. papyrifera were avoided. All nineteen tree species were, however, utilized to at least some degree by gypsy moth larvae.
• 5 These results quantitatively affirm and clarify earlier reports of gypsy moth feeding preferences in North America and Eurasia. The advantages and limitations of using an electivity index to estimate the susceptibility of different tree species to attack by folivores like the gypsy moth are discussed.

     

Behavioural response to an unsuitable host plant in the gypsy moth (Lymantria dispar L.)

To assess local differentiation in host preference, a two-choice test was performed on first-instar gypsy moth larvae originating from an oak and locust-tree forest. More than 40 generations feeding on locust-tree leaves, rich in alkaloids, led to non-efficient discrimination of host leaves in larvae from a locust-tree forest. Possible causes of observed population differences are discussed in the present paper.     

亚精胺对小菜蛾幼虫生长及保护酶活力的影响

在实验室条件下测定经亚精胺处理后,对小菜蛾Plutella xylostella L.3龄幼虫取食量、存活、羽化率、蛹重及保护酶活力的影响。结果表明,亚精胺对小菜蛾幼虫的取食量、存活、羽化及保护酶活力均有明显的影响。经过亚精胺处理后的大部分时间段,3龄幼虫的取食量、存活率、化蛹率及体内SOD和POD活力均明显高于蒸馏水对照;对处理后24和36h CAT活力也有明显的促进作用;但亚精胺对其蛹重、蛹的羽化率却无明显的影响。     

Performance of Lymantria xylina (Lepidoptera: Lymantriidae) on artificial and host plant diets

Lymantria xylina Swinhoe (Lepidoptera: Lymantriidae) is a serious defoliator of hardwood and fruit trees in Taiwan. The larvae of L. xylina feed on >63 species of host plants, belonging to 29 families. Because a large number of larvae are needed for the production of nucleopolyhedrosis virus (NPV) or other related studies, the development of a suitable artificial diet is very important for the mass rearing of this moth in the laboratory. In this study, eight artificial diets, modified from different formulas, and one host plant, Liquidambar formosana Hance, were used to feed L. xylina caterpillars. Through various bioassays (first instar survival trial and long- and short-term feeding trials), the most suitable diet for the L. xylina was selected by performance comparisons with L. formosana. After the first instar survival trial, two of the diets were discarded, because no larva survived on these diets. The results of the long-term feeding trial indicated that the larvae grew successfully on only three kinds of artificial diet. Finally, results of the short-term feeding trial revealed that a diet (diet A), modified from the gypsy moth, Lymantria dispar (L.), formula diet, was the most appropriate for the L. xylina. Larvae fed on diet A had better survival rate, pupal weight, adult size, efficiency of conversion, and relative growth rate than larvae fed on other diets; they did not grow as well as those fed on L. formosana, however, except for pupal and adult weight, and approximate digestibility. In summary, diet A was found to be the best of the artificial diets for the L. xylina and is suitable for mass rearing of this moth in the laboratory.     

Malaria Mosquitoes Host-Locate and Feed upon Caterpillars

Adult female mosquitoes need blood to develop their eggs and both sexes use nectar and honeydew as carbohydrate resources for flight, survival and to enhance reproduction. However, there are also a few reports in the literature of mosquitoes feeding on haemolymph of soft-bodied insects such as caterpillars. The frequency and significance of this entomophagous behavior is not well understood, but is thought to be a vestige of ancestral feeding behavior or an opportunistic behavior that has evolved over time. In our current paper we investigated the extent to which the malaria mosquito, Anopheles stephensi, is attracted to, and can successfully feed on, larvae of two common moth species, Manduca sexta and Heliothis subflexa. Using y-tube olfactometer assays we found that female An. stephensi readily flew upwind to and landed on the caterpillars of both moth species. The nature of the volatile cues used in host location remains unclear but respirometer studies suggest a possible role of CO₂. Laboratory cage assays further showed that the female mosquitoes were able to actively feed on moth larvae and gain sufficient nutritional benefit to influence survival. The extent to which such an opportunistic behavior occurs in the field has yet to be explored but our results suggest that this haemolymph feeding behavior could play a role in malaria mosquito life history and could provide a novel mechanism for horizontal transmission of pathogens and other micro-organisms between hosts.