不同翅型棉蚜体内游离氨基酸含量对比

为了深入了解棉蚜中氨基酸组成，利用氨基酸自动分析仪分别对不同翅型不同发育时期的棉蚜进行游离氨基酸含量的分析。结果显示，不同翅型棉蚜中均检测到相同的21种游离氨基酸。其中，必需氨基酸10种，非必需氨基酸11种。在若虫时期，有翅蚜游离氨基酸含量与无翅蚜无显著差异；在成虫时期，与无翅蚜相比，有翅蚜游离氨基酸含量显著上升了1.5倍，脯氨酸、甲硫氨酸等8种游离氨基酸含量显著升高；在2个发育时期，有翅蚜的亮氨酸和甘氨酸含量显著高于无翅蚜，而有翅蚜的精氨酸含量显著低于无翅蚜；有翅成蚜的非必需氨基酸含量比无翅成蚜显著上升0.65倍。推测有翅成蚜脯氨酸与甲硫氨酸含量较无翅成蚜的增加与有翅蚜抗逆性增强有关，而有翅棉蚜体内精氨酸含量较无翅棉蚜低可能与其繁殖力低有关。这些结果可为棉蚜翅型分化分子机理研究及其防治提供参考。     

影响褐飞虱和蚜虫翅型分化的外部因素

翅多型现象普遍存在于各类昆虫中,可划分为长翅型和短翅型.长翅型具有飞行能力而短翅型不行.导致褐飞虱和蚜虫发育出不同翅型的因素十分复杂,不同的温度、湿度、光照周期、虫口密度、若虫龄期以及寄主植物营养状况均会对其产生影响.就环境及生物因素对昆虫翅型分化的影响进行了综述.     

春小麦抗蚜性与麦长管蚜EST活性及GSH活性的关系

为阐明春小麦对蚜虫的抗生性机理及蚜虫对寄主的适应性机制,选用抗蚜性不同的8个春小麦品种（系）为试验材料,利用灌浆期人工接种的方法,研究了小麦抗蚜水平与麦长管蚜无翅型孤雌胎生蚜酯酶（EST）活性及谷胱甘肽转移酶（GSH）活性的关系。结果表明,蚜虫EST活性与春小麦抗蚜水平有关,GSH活性与小麦抗蚜水平无关。穗部及旗叶蚜虫EST活性均与其存活率呈显著负相关,相关系数分别为-0.7047（P=0.04523）和-0.7214（P=0.0380）,与有翅蚜分化率接近显著或显著负相关,相关系数分别为-0.6767（P=0.05911）和-0.7317（P=0.0336）,与仔蚜繁殖率相关不显著。穗部及旗叶上蚜虫GSH活性均与其存活率、有翅蚜分化率及仔蚜繁殖率不相关。     

糯玉米与棉花间作对蚜虫种群的调控作用

为探索棉田物种多样性对棉蚜的生态调控效应，于2016年系统调查了安徽安庆地区糯玉米与棉花不同面积比例间作模式下棉蚜与玉米蚜种群数量的时序动态。结果表明：在棉花苗蚜发生高峰期，棉花与糯玉米间作田棉蚜无翅蚜、有翅蚜发生高峰期的百株虫量分别极显著、显著低于单作棉田；在玉米蚜发生高峰期，与糯玉米单作田相比，棉花与糯玉米间作田玉米蚜无翅蚜和有翅蚜的百株虫量显著降低。因此，在蚜虫发生的高峰期，间作田蚜虫数量显著低于棉花、糯玉米单作，且以棉花与糯玉米面积比3∶1间作模式对2种蚜虫的控害作用最为明显。     

抗虫小麦对麦长管蚜发育和繁殖的影响

为了观察植物抗性压力对麦长管蚜（Ｓｉｔｏｂｉｏｍ ａｖｅｎｕｅ Ｆａｂｒ．）繁殖的影响，本文研究了蚜虫在抗性小麦品种和敏感小麦品种上从出生到死亡的寿命、繁殖、成虫重量及生殖腺状态；还研究了无翅蚜在两类品种间的迁移状况。将这种结果与若虫期或成虫期饥饿１０或１４ｈ后的蚜虫所获参数进行了比较。用成虫做试验的抗性植株与用幼虫做试验的同一植株所测得的每一参数极为不同，在抗性小麦上生长和繁殖的蚜虫与受半饥饿影响     

抗虫小麦对麦长管蚜发育和繁殖的影响

为了观察植物抗性压力对麦长管蚜（ｓｉｔｏｂｉｏｎ　ａｖｅｎｕｅ　Ｆａｂｒ．）繁殖的影响，本文研究了蚜虫在抗性小麦品种和敏感小麦品种上从出生到死亡的寿命、繁殖、成虫重量及生殖腺状态；还研究了无翅蚜在两类品种间的迁移状况。将这种结果与若虫期或成虫期饥饿１０或１４ｈ后的蚜虫所获参数进行了比较。用成虫做试验的抗性植株与用幼虫做试验的同一植株所测得的每一参数都极为不同，在抗性小麦上生长和繁殖的蚜虫与受半饥饿影响的蚜虫非常相似。     

用黄色粘虫板监测玉米田双斑萤叶甲和蚜虫种群动态与诱杀效果研究

2018和2019年7～9月在齐齐哈尔地区通过在玉米田间悬挂黄板(40 cm×25 cm),设距地面1.0 m和玉米雌穗上2种悬挂高度,每7 d更换,调查其对双斑萤叶甲、蚜虫诱杀作用及对主要天敌昆虫的诱集影响。结果表明,黄板对双斑萤叶甲成虫具有显著的诱杀作用,高峰期周平均最多诱杀188头/板。平均单板诱虫量变化反映出双斑萤叶甲7月初始发,8月中旬为盛发期,9月上旬为盛发末期。黄板对有翅蚜有一定的诱杀效果,平均单板诱集有翅蚜量与田间单株玉米上无翅蚜种群密度呈显著线性相关。蚜虫种群密度高峰期,黄板诱杀区单株平均蚜量比不挂黄板(对照区)显著减低44.8%～45.3%(2018)和21.0%～28.3%(2019)。黄板对瓢虫有一定的诱集作用,对草蛉、食蚜蝇等天敌基本无显著诱集作用。在齐齐哈尔地区黄板既可以用于田间监测玉米田双斑萤叶甲和蚜虫的种群发生动态,又具有诱杀和防治的潜力。     

小麦雨锈病蚜传特性的研究

1984年以来,进行了介体蚜虫传毒试验,证明禾谷缢管蚜、麦长管蚜、麦无网长管蚜、麦二叉蚜及玉米蚜均可传毒,传毒发病率分别为74.2％、59.0％、53.6％、31.5％和17.4％。禾谷缢管蚜传毒特性、取食获毒或传毒最短时闻为5分钟,发病率达6.67％。2小时可充分获毒或传毒。蚜虫传毒有间歇现象,持毒期3天,传毒潜伏期65—70分钟。由此可见,小麦雨锈病是由多种蚜虫传播的具有半持久性传毒特性的病毒病。禾谷缢管蚜传毒能力因龄期不同而有所差异,有翅蚜传毒能力最强,无翅成蚜次之,若蚜最低。接种一头带毒蚜虫即可引致发病,接种蚜头数增加,发病率提高,接种7头蚜虫,发病率可达84.2％。     

烟蚜与烟草黄瓜花叶病田间消长动态研究

为建立烟草黄瓜花叶病（CMV）的预测预报系统,对烟蚜、烟草黄瓜花叶病的田间消长动态进行调查．调查结果表明：烟蚜在田间洧长规律呈单峰型,有翅蚜峰日早于无翅蚜峰日10天,僵蚜峰日落后无翅蚜峰日5天;烟草黄瓜花叶病的发生与有趣蚜的迁入消长紧密相关．     

马铃薯田有翅蚜数量消长的研究

蚜虫既可以汲取汁液危害马铃薯降低产量,又可以作为多种病毒的传毒媒介引起马铃薯退化,而某些种类的有翅蚜是病毒传播的主要蚜型,因此,有翅蚜的监测对蚜虫的综合防治意义重大。本试验采用黄皿诱蚜器,在黑龙江省呼兰地区进行了两年的监测。结果表明:有翅蚜初次迁入时期一般在6月份,2003年为6月16日,2002年为6月28日;有翅蚜数量,随温度、降雨、风等因素的变化而波动;有翅蚜高峰期2002年主要集中在9月上中旬,9月4日为高峰日,数量达4126头／2 d;2003年6月26日为高峰日,数量达760头／2 d。     

Constitutive emission of the aphid alarm pheromone, (E)-β-farnesene, from plants does not serve as a direct defense against aphids

Background  

The sesquiterpene, (E)-β-farnesene (EBF), is the principal component of the alarm pheromone of many aphid species. Released when aphids are attacked by enemies, EBF leads aphids to undertake predator avoidance behaviors and to produce more winged offspring that can leave the plant. Many plants also release EBF as a volatile, and so it has been proposed that this compound could act to defend plants against aphid infestation by 1) deterring aphids from settling, 2) reducing aphid performance due to frequent interruption of feeding and 3) inducing the production of more winged offspring. Here we tested the costs and benefits of EBF as a defense against the green peach aphid, Myzus persicae, using transgenic Arabidopsis thaliana lines engineered to continuously emit EBF.     

Area control of the green peach aphid on peach and the reduction of potato leaf roll virus

Peach trees in a 500-mile² (1295 sq. K) area were sprayed during April and May each year from 1966 to 1969 to control the wingless fundatrix form ofMyzus persicae (Sulzer) after the overwintering eggs had hatched and before subsequent generations of the aphids had developed wings and migrated to summer host plants. The results were monitored from 1966 to 1971 by using about 60 yellow water trap pans each year to collect winged aphids in the control area. Also, aphids were counted weekly in about 30 potato fields each year. Samples of potato tubers collected from the 30 fields (and from 34 other fields in 1965) were indexed for net necrosis and then planted and indexed for chronic leaf roll. The early spraying reduced the populations of winged aphids collected in traps in May and early June 1966–1969 by about 60% compared with the post-spray years (1970–1971). The amount of net necrosis found in potato tubers from the control area was reduced from 11 % in 1965 to slightly more than 3% from 1967 through 1969 and the chronic leaf roll in plants was reduced from 43% in 1965 to about 10% for the same years. Only after two years of spraying was there evidence of a significant reduction in the spread of the virus; similarly, not until 2 years (1970 and 1971) following the end of the spray program did the virus increase significantly.     

Soybean aphid,Aphis glycines Matsumura, a new vector ofPotato virus Y in potato

Soybean aphid (Aphis glycines Matsumura), an exotic species first discovered in the North Central region of the United States in 2000, is a competent vector of severalPotyviridae. Soybean aphid has high fecundity and produces alatae (winged morphs) readily, characteristics typical of proficient virus vectors. When soybean aphids were exposed toPotato virus Y (PVY)-infected potato plants and then clip-caged on healthy potato plants in groups of five or as single aphids, PVY transmission ranged from 14% to 75% across all experiments. PVY^o, PVYⁿ, and PVP^ntn strains were transmitted by soybean aphid.     

Characterization of Solanum chomatophilum resistance to 2 aphid potato pests, Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer)

The aphids Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer) (Hemiptera: Aphididae) are responsible for yield reduction in potato (Solanum tuberosum) production by direct phloem feeding and by spreading viruses. Breeding resistant traits from Solanum chomatophilum into the potato germplasm provides alternative means to control aphid infestations. Integrated pest management strategy, using plant resistance, benefits from the characterization of the resistance and of its impact on aphid biology. Our objective was to characterize the resistance of S. chomatophilum by assessing the effects of accessions, plant parts on aphid performance, and by assessing the impact of the resistance factors on different aphid developmental stages and on alate morph production. Detailed aphid performance was obtained by measuring fecundity, survival, percentage of nymphs that reached adult moult, and population growth using whole plant and clip cage experimental designs. Accession and plant physiological age, but not aphid developmental stage, influenced all life-history parameters, except for alate morph production which was not induced on the resistant accessions. Plant part influence was independent of plant species and accession. Both experimental designs resulted in congruent resistance levels at the accession level for each of the two aphid species, supporting the use of any of them in S. chomatophilum resistance screening. PI243340 was resistant to both aphid species, while PI365324 and PI310990 were also resistant to M. euphorbiae and M. persicae, respectively.     

Comparison of water trap pans and leaf counts as sampling techniques for green peach aphids on potatoes

Green peach aphid populations were monitored by using water trap pans and by taking leaf samples in 38 southwestern Idaho potato fields from 1972 to 1975. Numbers of winged aphids in trap pans were correlated with populations of aphids developing in adjacent fields but were not predictive of future population trends. Trap pan data are, however, useful in alerting growers to the possibility of damaging field populations which exist in a field at the time of sampling.     

Insecticidal control of cereal aphids and its impact on the epidemiology of the barley yellow dwarf luteoviruses

Imidacloprid is a seed-applied nitroguanidine insecticide that has both contact and long-lasting systemic properties. Its direct effects on cereal aphid populations and indirect effects on barley yellow dwarf luteovirus (BYDV) incidence were examined in laboratory and field studies. Adult longevity and fecundity of three aphid species caged on various aged, imidacloprid-treated oat or wheat plants was reduced, although the quantitative efficacy of the compound differed among aphid species. The transmission efficiency of BYDV by aphids to imidacloprid-treated plants was lower, relative to nontreated plants, when plants were 10 days old, but similar to nontreated when plants were 24 days old. In three years of field trials using winter wheat and two years using spring oat, aphid populations were reduced significantly in imidacloprid-treated plots relative to nontreated plots. Although the number of alighting alate aphids did not differ significantly between imidacloprid-treated or nontreated plots, the number of apterous aphids remained significantly lower in the treated plots for the majority of the growing season. BYDV epidemics did not develop in spring oat in either of the two years. BYDV epidemics did develop in the fall in the emerging winter wheat crop. Rhopalosiphum maidis was the predominant aphid migrating into the 1991–1992 crop. The incidence of the BYDV-RMV serotype was three times higher in nontreated plots than in imidacloprid-treated plots. In the 1992–1993 and 1994–1995 seasons, R. maidis and R. padi were the predominant aphids migrating into the crop, although R. padi was the predominant colonizing aphid. The incidence of BYDV-RMV was similar in imidacloprid treated and nontreated plots in 1992–1993, but the incidence of the BYDV-PAV serotype was significantly less in the treated plots. In 1994–1995, the incidence of both BYDV-PAV and BYDV-RMV was higher in the nontreated plots than in the imidacloprid-treated plots. Imidacloprid offers several advantages both in terms of its long-lasting systemic activity and its mode of applicaiton. As a seed treatment, the amount of material applied is minimized, there is little waste and the environmental impacts are reduced. The effectiveness of the compound at reducing the fecundity or reproductive rate of several aphid species may be advantageous in controlling secondary spread of viruses. However, the contact properties of the compound, important in repelling aphids or preventing phloem feeding, may be short-lived, thus reducing its effectiveness in preventing primary spread of the virus into the crop, especially under high aphid and inoculum pressure.     

Control of root aphid (Pemphigus bursarius L.) in witloof chicory culture (Cichorium intybus L. var. foliosum)

Pemphigus bursarius L. is a serious pest of the witloof chicory (Cichorium intybus L. var. foliosum) during its growing phase in the field. Trials investigating many ways of improving control of this aphid were carried out, including improved knowledge of the pest's life cycle and of beneficial insects, tests of biological and chemical insecticides, impact of plants' growing conditions in the field (water stress) and research for resistance in different chicory families. The work showed that the winged flights of P. bursarius should be monitored in Northern France according to the temperature-based model established at Horticulture Research International, Wellesbourne (now Warwick Crop Center). An insecticide spray with spirotetramat during the fundatrigeniae migration strongly reduced the wingless colonies in summer. Beneficial insects also contributed to limiting the populations of P. bursarius, particularly several species of a genus of a fly (Thaumatomyia spp.) whose larvae are able to predate on about 100 wingless aphids on the root chicory. The use of an insecticide has been authorized based partly on efficacy results obtained in these reported trials. Italian chicories were more resistant than witloof chicories (“Belgian endive”) and could be used in breeding programs. Data on the life cycle of some species of the genus Thaumatomyia have been recorded and will be useful for biological management programs in the future.     

Rate of spread of PVYn by alateMyzus persicae (Sulzer) from infected to healthy plants under laboratory conditions

Summary Alate green peach aphids,Myzus persicae (Sulzer), tested in a flight chamber during their maiden flight period displayed behaviours ranging from repeated trivial flights to settling on the plants. The interaction of alate vector density and PVYⁿ spread was dichotomous, virus spread was significantly related to vector density in some trials but virus spread was nil or limited and not significantly dependent on vector density in others. The green peach aphid colony used in these experiments provided a mixture of active and highly active alate populations. Results suggest that inactive and active vectors came from the active and highly active alate populations, respectively. Therefore, winged aphids within a species cannot all be attributed the same vector efficiency unless known to originate from the same population. At a 15% inoculum level the intercept for the regression model for the spread of PVYⁿ was 5.03% indicating that there is a significant probability of propagation at aphid densities as low as one. However, over the range of aphid densities tested, the rate of spread per aphid was low, 0.08%, suggesting that reinfection of newly infected plants or movement interference between aphid vectors rapidly became important factors negatively affecting virus spread. Although these results cannot be directly transferred to field conditions they provide confirmation that lowM. persicae numbers can transmit unacceptable levels of mosaic and that low inoculum levels are required to decrease the risk of transmission by the small aphid numbers which cannot be realistically controlled.