南方小花蝽对不同猎物捕食作用及利用效率

室内用棉蚜,花蓟马及棉花花粉饲养南方小花蝽,通过对南方小花蝽捕食两种猎物及取食棉花花粉后的体重的增长以及同时段内对棉蚜,花蓟马及棉花花粉减少的量的测定,得到南方小花蝽取食不同食物后的生长速率及其对食物的利用效率,同时还研究了南方小花蝽成虫和若虫对混合猎物（棉蚜,棉铃虫卵,红铃虫卵）中各猎物的捕食作用及其在多猎物（红铃虫卵,棉叶螨成螨,花蓟马若虫）不同密度水平下的捕食效应。结果表明,棉蚜与花蓟马可以较好地满足南方小花蝽正常生长发育所需的营养,南方小花蝽对两种猎物的利用效率显著高于棉花花粉,在混合猎物中南方小花蝽成虫和若虫均嗜食棉蚜,其次为红铃虫卵和棉铃虫卵;对于同一种猎物,南方小花蝽成虫和若虫在高密度下的日平均捕食量均显著高于低猎物密度下的日平均捕食量,而对于同一密度的不同猎物,南方小花蝽在低猎物密度时对供试的3种猎物无明显的选择性,在中,高密度时对供试的3种猎物则表现出明显的嗜食性差异。其嗜好程度依次为红铃虫卵,花蓟马若虫,棉叶螨成螨,通过研究有助于更好地了解与掌握南方小花蝽对不同食物的需求及其在田间的食物转换规律,从而更好地进行南方小花蝽的室内人工大量饲养,使南方小花蝽更好地成为棉田害虫种群综合治理中的重要组成部分并发挥其应有的作用。     

四种猎物对南方小花蝽生长发育和繁殖的影响

南方小花蝽是多种猎物的天敌,为评价西花蓟马、二斑叶螨、蚕豆蚜和腐食酪螨饲养南方小花蝽的效果,研究了南方小花蝽取食四种猎物时的生长发育和繁殖情况。结果表明南方小花蝽取食腐食酪螨时若虫只能发育到5龄,4龄若虫累计存活率仅为6.8%。其它3种猎物均可使南方小花蝽正常生长发育和繁殖,其中南方小花蝽取食西花蓟马时生长发育时间最短,繁殖率最高;取食二斑叶螨时生长发育时间最长,繁殖率最低。取食西花蓟马的南方小花蝽净生殖率、内禀增长率和周限增长率明显高于其它两种猎物。用3种猎物连续饲养南方小花蝽两代,以蚕豆蚜和二斑叶螨为猎物时南方小花蝽的未成熟期、成虫的寿命、繁殖情况和生命参数在第一代和第二代之间都有所不同,但以西花蓟马为食料时南方小花蝽第一代和第二代之间生长发育和繁殖情况没有明显的差异。以上结果表明在供试猎物中西花蓟马对南方小花蝽实验种群的增长最有利。     

阿维菌素对南方小花蝽的毒杀作用

在室内条件下,研究了阿维菌素两种产品对南方小花蝽的毒杀效果.结果表明,两种产品对南方小花蝽不同虫态均有一定的毒杀作用.成虫、若虫对阿维菌素的敏感性基本相同,而卵的敏感性最低.阿维菌素对南方小花蝽除有直接的毒杀作用外,对其捕食能力也有一定影响.     

南方小花蝽对寄主植物的产卵选择性及其卵的保存条件

室内研究南方小花蝽Orius similis Zheng在9种产卵寄主植物(辣椒,豇豆,长寿花,迎春花,黄荆,绿豆芽,棉花,石莲花,太阳花)的嫩茎上的产卵量、孵化率及繁殖系数。结果表明,南方小花蝽对不同产卵植物具有显著的选择差异性。从产卵量看,对辣椒嫩枝选择性最强,其产卵量占总产卵量的23.4%;从孵化率看,产在迎春花嫩茎上的卵的孵化率最高;从繁殖系数看,辣椒嫩枝和迎春花嫩茎作为产卵植物的繁殖系数较高,分别为7.6和12.8;从辣椒嫩枝和迎春嫩茎上的繁殖系数的构成看,两者明显属于2种不同的类型,前者属于高着卵量、低存活率类型,后者属于低着卵量、高存活率类型。对南方小花蝽不同虫态进行了抗寒能力的测定,结果表明南方小花蝽卵的抗寒能力最强,成虫次之,1~2龄若虫最弱。在此基础上做了卵的低温保藏实验,结果表明要保证80%以上的孵化率,最佳保藏条件为8℃下保藏9天。     

军配盲蝽和南方小花蝽对茶网蝽若虫的捕食作用

茶网蝽Stephanitis chinensis是一种为害春茶的重要害虫,本文研究了天敌军配盲蝽Stethoconus japonicus和南方小花蝽Orius similis对茶网蝽的捕食能力,为茶网蝽的生物防治提供科学依据。在室内开展军配盲蝽和南方小花蝽对茶网蝽3龄若虫的捕食功能反应和寻找效应以及南方小花蝽的种内干扰反应研究。结果表明军配盲蝽和南方小花蝽对茶网蝽3龄若虫的捕食功能反应均符合Holling Ⅱ型。军配盲蝽和南方小花蝽的捕食量与茶网蝽3龄若虫的密度呈正相关,但寻找效应与猎物密度呈负相关。南方小花蝽成虫、3龄若虫对茶网蝽3龄若虫的日最大捕食量（11.49头、12.82头）大于军配盲蝽成虫、3龄若虫（10.10头、6.41头）;军配盲蝽成虫对茶网蝽的寻找效应高于其3龄若虫,而南方小花蝽3龄若虫的寻找效应高于成虫。南方小花蝽成虫、3龄若虫对茶网蝽3龄若虫的捕食作用均存在种内干扰反应,且符合Hassell模型,分别为E=0.4263P^-0.825和E=0.5234P^-0.762。综上研究结果,军配盲蝽和南方小花蝽对茶网蝽3龄若虫的捕食作用较强,均具有良好的生物防治潜能。     

桃蚜提取液对南方小花蝽行为的影响

在室内(25±1℃,RH70%)条件下,研究了桃蚜Myzus persicae不同溶剂提取液对南方小花蝽0rius similis行为的反应.结果表明,桃蚜虫体用水研磨的浆液、用水或95%乙醇研磨提取的滤液,均含有很强的活性物质,而且用乙醇提取的滤液活性更强.其中桃蚜虫体用水研磨的浆液对南方小花蝽行为有很显著的影响.南方小花蝽对提取的活性物质均表现有明显的滞留和调转行为.     

阿维菌素对南方小花蝽抑制烟蚜的影响

在室内分别测定了阿维菌素类杀虫剂1% 9512-1乳油和虫螨克对南方小花蝽Orius similis的毒力,研究了无阿维菌素介入后南方小花蝽对烟蚜Myzus persicae捕食效应所受的影响,结果表明：阿维菌素类杀虫剂对南方小花蝽具有一定毒力,不同虫态对阿维菌素的敏感性有差异,卵的敏感性明显低于若虫和成虫;不同的阿维菌素类药剂对南方小花蝽的毒力存在差异,9512-1对南方小花蝽卵、若虫及成虫的LC_５０依次为11.2743±3.8613、2.6584±1.2139、2.4508±1.3266 mg·L^-１,虫螨克则为10.8699±3.7653、6.4422±2.8596、6.4738±3.0124 mg·L^-１;阿维菌素显著降低了南方小花蝽对烟蚜的捕食量和捕食能力,也降低了同种个体间的竞争能力;阿维菌素对南方小花蝽若虫的发育速率有显著的抑制作用,但对发育速率与取食量的线性关系无明显影响,而且对存活个体成虫期的产卵量无显著影响。     

南方小花蝽触角感器的扫描电镜观察

南方小花蝽Orius similis Zheng捕食能力较强,对田间多种小型害虫有明显的控制作用,是一类重要的捕食性天敌。本文利用扫描电镜分别对新羽化的南方小花蝽雌、雄成虫和5龄若虫的触角形态和感器进行了观察。结果发现,南方小花蝽雌、雄成虫以及5龄若虫触角均为线状,共4节,分为柄节、梗节和鞭节。触角上共有5种感器,分别为毛形感器、刺形感器、锥形感器、具弯钩形感器和耳形感器,其中毛形、刺形感器各有2个类型,耳形感器是首次在蝽类昆虫触角上发现。雌、雄成虫的触角存在性二型现象,雄成虫触角感器数量明显多于雌成虫;若虫的感器类型及数量比成虫少。不同类型的感器在触角各节上的数量与分布各不相同。本文以期深入了解其化学感受系统,为揭示南方小花蝽的寄主选择行为机制提供基础。     

南方小花蝽液体人工饲料的饲养效果评价

为评价一种液体人工饲料的饲养效果,以棉蚜饲养南方小花蝽作对照,用液体人工饲料连续两代饲养南方小花蝽若虫和成虫,对南方小花蝽各生长阶段的生长和发育指标进行调查。结果显示：用人工饲料饲养的南方小花蝽若虫历期（22～23天）与对照组（21天）之间不存在显著差异,说明液体人工饲料可以很好的满足南方小花蝽若虫生长的营养要求。然而,用棉蚜饲养的对照组南方小花蝽成虫获得率可达到63%,而人工饲料组连续两代的成虫获得率分别仅为45% 和43%。取食人工饲料的南方小花蝽成虫,在产卵前期、产卵量及寿命方面与对照组都没有显著差异,仅在产卵期方面有着显著差异,人工饲料组小花蝽的产卵期为13～16天,而对照组小花蝽的产卵期可达20天,说明液体人工饲料也可以很好的满足南方小花蝽成虫生殖发育的营养要求。     

南方小花蝽对西花蓟马和蚕豆蚜的捕食作用

南方小花蝽Orius similis是多种小型害虫的重要天敌昆虫,为了掌握其控制潜能,本文研究了南方小花蝽对西花蓟马Frankliniella occidentalis和蚕豆蚜Aphis craccivora的捕食作用。研究结果表明南方小花蝽3～5龄若虫和雌成虫对西花蓟马和蚕豆蚜的功能反应均符合HollingⅡ型方程,南方小花蝽3～5龄若虫和雌成虫对西花蓟马2龄若虫的瞬时攻击率均高于蚕豆蚜。南方小花蝽5龄若虫对蚕豆蚜的控制能力比雌成虫强,而对西花蓟马的控制能力比雌成虫差。南方小花蝽5龄若虫对西花蓟马2龄若虫和蚕豆蚜的捕食率（E）随着捕食者自身的密度（P）的增加而下降,其干扰反应方程分别为E=0.412P-1.623和E=0.416P-1.639。南方小花蝽5龄若虫对西花蓟马2龄若虫和蚕豆蚜有明显的选择性,5龄若虫喜欢取食西花蓟马2龄若虫,但前期取食的猎物对其选择性有明显的影响,更喜欢选择前期取食过的猎物。     

Rearing of Orius strigicollis (Heteroptera: Anthocoridae) on Artificial Diet

Orius strigicollis (Poppius) was reared on the modification of rearing media for Tetrastichus sp. at 28°C, 18L: 6D, and 50‐60% RH, in which meat diets were used for partial replacements of insect source of the artificial diets. Life history traits of the predacious bug fed on the diet were measured. Nymphal development period and mortality rate of O. strigicollis were about 14 days and 31.5% (survival rate: 68.5%), respectively. The female bug produced average of 82.5 eggs during its oviposition period of 18 days when artificial oviposition substrate was provided. The fecundity was shown to be superior compared with previous researches on the species fed natural preys as a food.     

Management of Sitotroga cerealella in stored cereal grains: a review

The economic loss due to pest attack in stored commodities is a serious problem worldwide. About 200 insect species attack stored commodities. These insect pests are responsible for quantitative and qualitative losses in cereal grains. Among the stored grain pests, Angoumois grain moth, Sitotroga cerealella is considered as common, top of the list and most destructive pest of cereal grains. Its infestation starts in the standing crop and continues in storage. Although there are many control strategies, our need is some effective, cheap and readily available strategy for safe storage. This review presents different ways by which S. cerealella can be controlled. In this paper, a list of approaches is given which are used to improve the protection of stored grains against S. cerealella attack. These approaches include use of edible oils, containers, synthetic chemicals, agricultural waste materials, plant derivatives, bacterial protoxins, biopesticides, biocontrol enhancers and semiochemicals. If these tactics are followed as combined strategies in a compatible manner, they can provide us an integrated pest management programme for the efficient control of S. cerealella in cereal grains.     

Grain damage,viability and weight loss in different barley cultivars due to Sitotroga cerealella (Oliv.) infestation

This study was carried out to see the impact of Angoumois grain moth (AGM) on different cultivars of barley so that we must grow resistant variety of barley or improve those which are susceptible to it. Eggs of Sitotroga cerealella (Oliv.) were collected and reared in incubators available in Stored Product Entomology Laboratory, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, under temperature 27 ± 2°C and 60 ± 2% relative humidity. For the experiment, five different cultivars of barley; Sanober-96, Jau-83, Soorab-96, ICBA and Sterling were selected for AGM feed. After an interval of 30, 60 and 90 days of infestation, percentage damage and weight loss in grains were determined. After carrying out laboratory and field germination tests, viability of different cultivars were checked. Damage was maximum in variety Soorab (99.38%), which becomes susceptible while it was minimum in Sanober-96 (90.62%), which becomes resistant. Weight loss was maximum in variety Soorab (49.71%), which becomes susceptible and was minimum in Sanober-96 (45.32%), which becomes resistant. Damage was positively correlated with weight loss and negatively correlated with seed germination. In germination tests, on filter paper, maximum germination was found in variety Sterling (3%) which becomes resistant and it was minimum in ICBA which becomes susceptible (0%). In sand germination test, maximum seeds germinated in variety Sanober-96 (2%), and minimum seeds germinated in ICBA (0%). By calculating the percentage of losses of different cultivars, it was found that none of cultivars proved itself completely resistant or susceptible.     

Insecticidal activities of garlic substances against adults of grain moth,Sitotroga cerealella (Lepidoptera: Gelechiidae)

Abstract The angoumois grain moth, Sitotroga cerealella (Olivier), is one of the most serious stored grain pests around the world. In attempts to reduce the losses caused by the moth and to suppress its populations, the fumigant activities, behavioral influence and ovipositional inhibition of garlic (Allium sativum) essential oil and its two major components, diallyl disulfide and diallyl trisulfide, were investigated against the adult grain moth. Their effects on reduction in survival of first instar larvae to adult emergence were also evaluated. Results showed that these three materials (garlic essential oil, diallyl disulfide and diallyl trisulfide) had significant fumigant activity with 50% lethal concentration values at 1.33, 0.99, and 1.02 μL/L air space, respectively; meanwhile, the three materials possessed high behavioral deterrent activities against adults in the Y‐tube olfactometer. When applied to rice grains, these materials reduced adult longevity and inhibited oviposition, with ovipositional inhibition above 70% at a concentration of 1.5 μL/25 g in either no‐choice or two‐choice tests. In short, the study showed that both diallyl disulfide and diallyl trisulfide, like garlic essential oil, acted as fumigants, produced behavioral deterrence and inhibited oviposition against angoumois grain moth. Our work here indicates that diallyl disulfide and diallyl trisulfide may serve as potential alternatives for grain protectants since both of them can be prepared easily from readily available chemicals.     

Insecticidal efficacy of some plant powders and extracts against the Angoumois grain moth,Sitotroga cerealella (Olivier) (Lepidoptera: Gelechiidae)

Powder and extract from four plants were evaluated for their insecticidal efficacy against the Angoumois grain moth, Sitotroga cerealella (Olivier) in the laboratory at a temperature of 28 ± 2°C and a relative humidity of 75 ± 5%. The plants included Aristolochia ringens L., Khaya ivorensis (K.), Strophanthus hispidus (D.C.) and Zanthoxylum zanthoxyloides Lam. The powder was applied at the rate of 0.2, 0.4 and 0.6 g/20 g of paddy rice, while the extract was applied at the rate of 1%, 2% and 3%/20 g of paddy rice. Parameters evaluated were adult moth mortality, adult emergence and weight loss in treated paddy after infestation. Results shows that adult moth mortality increased as concentration of powder increased. Significant differences (p < 0.05) existed among the plant powders andthe concentration. A 100% mortality rate was obtained within 7 days when A. ringens was applied at 0.4 and 0.6 g/20 g of paddy. S. hispidus was able to effect 100% mortality only at 0.6 g. This shows that A. ringens had the greatest insecticidal activity while the least effective was K. ivorensis. Adult emergence shows that more adult S. cerealella emerged from the control (40.3) which was significantly higher (p < 0.05) than others. Fewer adults emerged from paddy treated with plant powder with the least in A. ringens. Generally, adult emergence reduced with an increase in the concentration of powder. The extract from all the four plants tested against S. cerealella was able to effect 100% mortality of the adult moths within 24 h of application at all concentrations. Significant differences (p < 0.05) existed among all the different plant powders in terms of weight loss. The weight loss in paddy was significantly higher (p < 0.05) in the control (57.7%) than others. Weight loss was least in paddy treated with A. ringens at 0.4g/20 g of paddy with 2.2%. Generally, weight loss decreased with increase in powder concentration. The treatment with the highest adult emergence (control) also had the highest weight loss, while the treatment with the lowest adult emergence (A. ringens) had the lowest weight loss.     

麦蛾的求偶行为与区分等级的方法

求偶行为是麦蛾的本能,主要由自身生理状态决定,雌蛾全是自发行为,雄蛾多是对异性信息刺激的反应。两性求偶行为都有固定发生程序,有明显的阶段性。本文按其阶段程序特点把两性求偶行为各分为3等9级。非求偶行为概作0等0级。等级数值大小反映了性兴奋强度,统计分析级别数值,就能确定个体或蛾群求偶行为的动态。     

Life tables and predation activity of Orius laevigatus and O. albidipennis at three constant temperatures

Effects of three constant temperatures (15, 25, and 35 -C) on development and reproduction of Orius laevigatus (Fieber) and O. albidipennis (Reuter) (Heteroptera: Anthocoridae) and on their predation activity against the western flower thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) were investigated in the laboratory. Small rooted plants of Spanish pepper (Capsicum annuum L. cv. Creta, long red) served as oviposition substrate and moisture source. Survival of eggs and nymphs of both species was high at 25 and 35 °C. At 15 °C, none of the eggs of O. albidipennis hatched and the number of nymphs completing the immature stage was extremely low. Developmental time of nymphs was not significantly different between species at 15 °C, but at 25 and 35 °C nymphs of O. laevigatus took significantly longer to develop than those of O. albidipennis. Females of O. albidipennis lived longer than those of O. laevigatus at 15 and 35 °C, but no differences were observed at 25 °C. Fecundity of O. albidipennis was greatly reduced at 15 °C, whereas a temperature of 35 °C was close to the upper reproduction threshold of O. laevigatus. Fecundity was highest at 25 °C for both species. At 15 °C, the intrinsic rate of increase (r_m) reached a minimum for both species. For O. albidipennis, the r_m-value increased with temperature (0.121 at 25 °C and 0.202 at 35 °C), whereas for O. laevigatus it peaked at 25 °C (0.105) but decreased at 35 °C (0.051). At 15 and 25 °C, adults of O. laevigatus consumed more F. occidentalis adults during their total lifespan than those of O. albidipennis, but the latter showed a better predation activity at 35 °C; in all treatments, however, adults of O. laevigatus consumed more prey per day than did those of O. albidipennis. The performance of both anthocorids at the different temperatures is discussed in relation to their practical use in integrated pest control programmes.     

Effects of three mealybug species on the development,survivorship and reproduction of the predatory lady beetle Cryptolaemus montrouzieri Mulsant

The lady beetle Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) is an important predator of mealybugs. The development, survivorship, longevity and reproduction of C. montrouzieri feeding on three different mealybug species [Dysmicoccus neobrevipes Beardsley, Ferrisia virgata Cockerell and Planococcus minor (Maskell)] were investigated in the laboratory at 26 ± 1°C, 75-–90% RH and 14:10 (L:D) h photoperiod. Results indicated that, when feeding on different mealybugs, no significant differences were observed between developmental periods and survivorship of C. montrouzieri (from egg to adult), but differences were recorded between the sex ratios, preovipositional periods, adult longevities and reproduction of the differently treated lady beetle populations. The highest sex ratio (0.56), the longest preovipositional period (6.6 days) and adult longevity (84.8 days for females and 93.9 days for males), and the maximum fecundity (659.0 eggs/female) of C. montrouzieri were recorded when feeding on F. virgata. Moreover, C. montrouzieri had a high net reproductive rate (313.66), intrinsic rate of increase (0.0816) and finite rate of increase (1.085) when feeding on F. virgata. Results indicated that the population growth of C. montrouzieri may increase faster when feeding on F. virgata than feeding on either of the other two mealybugs.     

Development,survival and reproduction of Orius niger (Hemiptera:Anthocoridae) under different photoperiod and temperature regimes

The successful use of the predatory bug Orius spp. (Hemiptera:Anthocoridae) for the biological control of pests, namely western flower thrips Frankliniella occidentalis (Pergande), in greenhouses during winter depends on overcoming the obstacles of short photoperiods and low temperatures which limit the efficacy of the predators through diapause induction, slowed development, reduced survival and reproduction. Thus, research has focused on determining the insect species least vulnerable to these problems. This study investigated the effect of varying day-lengths (9, 11, 13 and 16 h) at 26°C as well as constant (18, 22, 26 and 30°C) and fluctuating (10/22°C) temperatures on biological characteristics of Orius niger (Wolff). Photoperiod did not induce reproductive diapause and did not significantly affect development, survival of eggs and nymphs, longevity, fecundity or sex ratio; with the exception of the 16 h day-length which led to a shorter duration of nymphal development. Fluctuating temperatures and a constant temperature of 18°C increased the incubation period, duration of nymphal development, total developmental time, generation time and longevity, compared to the constant temperatures of 22, 26 and 30°C, but decreased fecundity compared to 22 and 26°C. On the other hand, sex ratio was not influenced by 10/22 and 18°C. Egg hatch rate and nymph survival differed significantly between temperature regimes, being lower at 18 and 10/22°C. These results suggest that O. niger would be able to survive and reproduce under winter conditions in unheated Mediterranean greenhouses and is a candidate for use in the biological control of pests.     

二种活体饲料对东亚小花蝽生长发育和生殖的影响

本文比较了果蝇Drosophila melanogaster(Meigen)幼虫和西花蓟马Frankliniella occidentalis(Pergande)2种活体饲料对东亚小花蝽Orius sauteri(Poppius)生长发育和生殖的影响。结果显示:果蝇幼虫饲喂的东亚小花蝽幼虫发育历期12.36d,与西花蓟马饲喂的(12.19d)相近。果蝇幼虫饲喂的东亚小花蝽产卵量(89.58粒)与西花蓟马饲喂(95.72粒)相当。表明果蝇幼虫与传统活体饲料西花蓟马饲养东亚小花蝽的效果相当,可以很好的满足东亚小花蝽生长发育和生殖的要求。由于西花蓟马饲喂成本比较高,实际操作中有一定困难,果蝇幼虫是一种较为理想的活体饲料。