Binodoxys communis is a dominant endoparasitoid of aphids in cotton fields, yet empirical evidence on how temperature and humidity regulate its growth, development, and reproduction remains limited. To address this gap, we assessed the effects of both constant and fluctuating temperature, as well as various combinations of temperature and humidity, on the longevity, parasitism, and fecundity of this parasitoid. Our results revealed that adult longevity of B. communis was longer at 20 °C and 25 °C while significantly shortened at a high temperature (35 °C). Similarly, the parasitism rate, female ratio, emergence duration, and offspring longevity of the parasitoid were all superior at 20 °C and 25 °C compared to 15 °C and 35 °C. Moreover, the longevity of both male (6.96 ± 0.10 d) and female (6.88 ± 0.07 d) parasitoids was significantly extended at 25 °C and 60% RH. Temperature had a marked impact on the parasitic capability of parasitoids, with the number of Aphis gossypii parasitized daily by B. communis being significantly higher at 25 °C than at 15 °C and 35 °C. Nevertheless, humidity and the interaction between humidity and temperature had no significant influence on parasitic capacity. The parasitism of B. communis followed the Holling-II model, with the highest daily maximum parasitism observed at 25 °C. In conclusion, our study showed that 25 °C positively enhanced the fitness of B. communis, providing a valuable reference for indoor population expansion and field release of B. communis, potentially enhancing its effectiveness as a biological control agent against aphids.

Hexaflumuron, a benzoylurea insecticide, exhibits high toxicity against various insect pests. Sublethal doses of hexaflumuron significantly impair nymphal development and subsequent fecundity in the resulting Apolygus lucorum (Meyer-Dür) adults. However, the effects on adults of A. lucorum that are exposed to sublethal concentrations of hexaflumuron are not known. In this study, we evaluated the toxicity of hexaflumuron to 1st- and 3rd-instar nymphs, as well as one-day-old adults, of A. lucorum using an artificial diet with hexaflumuron incorporated. Acute toxicity bioassays determined the median lethal concentration (LC50) for 1st- and 3rd-instar nymphs of A. lucorum to be 0.311 and 0.337 mg/L. In contrast, the LC50 level for one-day-old adults of A. lucorum was 13.193 mg/L. To evaluate the sublethal effects of hexaflumuron on 3rd-instar nymphs, we used LC10, LC20, and LC50 concentrations (0.018, 0.127, and 0.337 mg/L), fed for 48 h. The exposure of 3rd-instar nymphs to the LC50 concentration significantly reduced the fecundity of adults. We also exposed one-day-old adults to LC10, LC20, and LC50 dietary concentrations (0.089, 4.587, and 13.193 mg/L) for 48 h. Exposure to the LC10 and LC20 concentrations caused significant reductions in longevity and fecundity in adult females. The LC50 concentration also caused a significant reduction in the longevity of adult males and the egg hatching rate. An understanding of these sublethal impacts can facilitate the development of effective control strategies targeting A. lucorum.

Alterative nutritional foods consumed by adult parasitoids play an important role in their fitness and ability to control pests because of food scarcity in many crops. While adult parasitoids feed on various sugars, they vary in their nutritional value for parasitoids. We assessed the effects of seven sugars (fructose, glucose, sucrose, trehalose, maltose, melezitose, and sorbitol) on the longevity, parasitism ability, parasitism behavior, and flight ability of B. communis, an important parasitoid of cotton aphids. We found that access to glucose, sucrose, or fructose, increased B. communis adult longevity more than the other sugars offered. All sugars except trehalose increased the parasitism rate to more than 50% compared to the starved control (only provided with water). We then compared parasitoid behaviors of wasps fed glucose, sucrose, or fructose to that of the starved control (with access only to water) and found that those fed B. communis spent more time either examining or attacking aphids than parasitoids in the control group, which spent more time walking or resting. Also, consumption of glucose, sucrose, or fructose also significantly improved the flight ability (the total flight distance, flight time, and average flight speed) of B. communis.

【Objective】 To evaluate the effects of different carbohydrates on the predation and flight ability of Hippodamia variegata with a view to providing a theoretical basis for better exerting the pest control efficiency of H.variegata.【Method】 After supplementing with different carbohydrates, the predation of H.variegata under different densities ofAphis gossypii was measured indoors, and the flight parameters of H.variegata under different treatments were measured by an indoor flying mill system.【Results】 The predatory functional response of H.variegata adults to the fourth instar nymphs of A.gossypii after supplementing with different carbohydrates was Holling-Ⅱ. After supplementing carbohydrates nutrition, as the density of the prey gradually increases, the predation ability of H.variegata increases, and the searching ability gradually decreases. Compared with the treatment of water, the predation and searching ability of H.variegata under the treatment of glucose and sucrose have both increased, The daily maximum number of scales preyed theoretic by female H.variegata adults was 675.68 and 757.58 respectively, and The daily maximum number of scales preyed theoretic by male H.variegata adults was 374.53 and 609.76 respectively; after supplementing glucose, fructose, sucrose, maltoseand raffinose, the cumulative flight time and cumulative flight distance of H.variegata prolonged significantly; the accumulate flight time was 7.78, 6.17, 7.58, 6.80 and 6.63 h respectively, and the accumulate flight distance was 9.51, 7.70, 8.46, 6.94 and 7.12 km respectively of female H.variegata adults; the accumulate flight time was 4.69, 4.99, 5.17, 5.09 and 5.20 h respectively, and the accumulated flight distance was 4.53, 5.41, 5.28, 4.72 and 5.52 km respectively of male H.variegata adults; after supplementing glucose and maltose, the maximum flight time and flight distance of female H.variegata was significantly extended, the maximum flight time is 1.99 and 2.88 h respectively, and the maximum flight distance is 2.90 and 2.83 km respectively; supplementation of different carbohydrate nutrients had no significant effect on the flight speed of adult H.variegata.【Conclusion】 Supplementation of glucose and sucrose can improve the predation and searching ability of H.variegata, and supplementation of glucose and maltose can improve the flight ability of H.variegata.

Omnivorous insects make foraging decisions between plant and prey resources depending on their accessibility, availability, and nutritional value. This shapes the stability and complexity of food webs, but also pest control services in agroecosystems. The mirid bug Lygus pratensis is a common cotton pest in China, but it also feeds on a variety of prey species. However, little is known about how different types of available resources affect its fitness and foraging behaviour. In laboratory experiments, we measured the fitness (survival, longevity and fecundity) of L. pratensis fed with bean pod only, bean and Aphis gossypii nymphs, or bean and Helicoverpa armigera eggs, and we also conducted focal observations of its foraging behaviour when provided the latter two. Adding H. armigera to its diet increased its fitness (both survival and fecundity), while adding A. gossypii was marginally detrimental. The different diets did not affect the time spent walking (searching for food resources) or preying, but significantly affected the time spent sapping bean tissue depending on L. pratensis life stage. Nymphs spent more time sapping plant when provided with H. armigera than A. gossypii (possibly through higher efficiency of handling prey). In addition, adults spent less time sapping plant than did nymphs (possibly through good efficiency of handling A. gossypii mobile prey and due to higher protein requirements). This special case of life-history omnivory highlights the complexity of natural food webs, where a major crop pest at the juvenile stage may become a biological control agent at the adult stage.

[目的]研究铷元素标记技术分析多异瓢虫在甘草带与邻近棉田间的迁移范围,丰富铷(Rb)元素标记技术在昆虫迁移扩散的作用.[方法]在室内利用铷元素标记技术检测多异瓢虫体内的铷元素滞留期;在田间利用铷元素标记技术,研究多异瓢虫从甘草带向棉田的迁移范围.[结果]铷元素在多异瓢虫成虫体内滞留期为15d左右;多异瓢虫成虫和幼虫从甘草向棉田的转移范围有所不同;成虫的铷元素检出率 0～15m>30～50 m>15～30 m>50～100 m.[结论]铷元素标记技术可以在田间有效的跟踪多异瓢虫成虫和幼虫的迁移范围.

Licorice strips in the immediate vicinity of cotton fields benefit generalist arthropod predators and improve aphid biological control throughout the cotton cropping season. These findings help to integrate habitat management within integrated pest management (IPM) frameworks in the biggest cotton production region of China. © 2022 Society of Chemical Industry.

本研究于2015—2017年通过扫网法系统调查了北疆棉田周边17种常见杂草上草蛉种群密度与季节动态.结果表明:北疆棉区杂草带上共有6种草蛉分布,其中普通草蛉Chrysopa carnea(占64.8％)、叶色草蛉C.phyllochroma(占25.8％)为优势种.草蛉种群密度在不同杂草上存在显著差异,紫花苜蓿、大麻上的草蛉密度分别在2015年、2016年显著高于其他杂草,2017年甘草、罗布麻、苦豆子上的草蛉密度较高.另外,草蛉密度呈现出明显的季节性波动,棉花花铃期(7月—8月)、吐絮期(9月)杂草上草蛉密度显著高于棉花苗期与蕾期(5月—6月).本研究明确了北疆棉区草蛉种类组成结构,筛选出紫花苜蓿、大麻、甘草、罗布麻、苦豆子5种对草蛉存在潜在保育作用的功能杂草,为利用田埂杂草促进棉田草蛉类天敌的保育控害提供了科学依据.

研究新疆维吾尔自治区夜蛾科Noctuidae时发现2个中国新记录种:中亚卡夜蛾Chersotis transiens (Staudinger,1896)、菲秀夜蛾Apamea ferrago(Eversmann,1837).对所研究的物种给予了详细的外部形态特征和生殖器描述,并提供了国内外分布信息.

对新疆夜蛾科美冬夜蛾属昆虫进行了整理,共记录了5种,分别为白点美冬夜蛾Xanthia ocellaris(Borkhaus-en,1792)、淡黄美冬夜蛾X.icteritia(Hufnagel,1766)、齿美冬夜蛾X.tunicate(Graeser,1889[1890])、褐黄美冬夜蛾X.gilvago(Denis&Schiffermüller,1775)和黄紫美冬夜蛾X.togata(Esper,[1788]),其中淡黄美冬夜蛾和齿美冬夜蛾为新疆新记录种.提供了分种检索表,每种成虫及外生殖器图片.

棉蚜(Aphis gossypii是一种生活史较复杂的杂食性农业害虫,由于以不同地域气象因素和植被的差异,限制了其生活史类型和越冬寄主种类.分析全球研究棉蚜生活史策略文献,以棉蚜能否以卵越冬为主线,分析世界不同区域棉蚜的2种生活史类型,对棉蚜异寄主全周期型这一生活史策略的原生寄主进行梳理.通过分析棉蚜在不同区域的生活史策略及其越冬寄主,有助于深入研究农作物保护策略,为棉蚜的系统化防治奠定理论基础.

[目的]分析田埂碱蓬带对棉田多异瓢虫种群发生的影响,为合理利用非棉田生境实施棉蚜的生态治理提供科学依据.[方法]采用田间种群系统调查和天敌控害功能罩笼评价.[结果]田埂碱蓬带是棉田多异瓢虫的重要来源;有碱蓬带的棉田中多异瓢虫种群密度、多异瓢虫与棉蚜的益害比均高于没有碱蓬带的对照棉田,其中多异瓢虫平均密度是对照棉田的1.9倍、益害比是对照棉田的8.8倍;利用罩笼进行天敌隔离处理,第7和14 d处理组(封闭罩笼)棉花上棉蚜种群增长率均显著高于开放罩笼的对照组;有碱蓬带的棉田中捕食性天敌对棉蚜的控害指数显著高于对照棉田.[结论]棉田田埂碱蓬带能有效增加棉田中多异瓢虫种群密度并提高益害比,对控制棉田棉蚜发生发挥着重要作用.碱蓬在天敌保育与控害中有重要作用,棉田周边予以留种.

[目的]研究田埂边苦豆子(Sophora alopecuroidesL.)条带对棉田内捕食性天敌发生及其控蚜作用的影响,为棉花生产中田埂合理保留保育天敌的功能性杂草、促进棉田天敌保育与害虫自然控制提供科学依据.[方法]系统调查田边苦豆子条带及棉田天敌与害虫种群,罩笼评价天敌控害功能.[结果]苦豆子与棉花上捕食性天敌种类基本相同、群落结构相似,苦豆子条带上各类主要捕食性天敌的数量均显著高于棉田.处理棉田(棉田边有苦豆子条带)中瓢虫、草蛉、蜘蛛密度分别为对照棉田(棉田边无杂草)的1.3、3.4和4.5倍,发生高峰期较对照棉田提前一周左右.6月上旬和8月,处理棉田的捕食性天敌和蚜虫之间的益害比显著高于对照棉田.处理棉田捕食性天敌对棉蚜控害指数显著高于对照棉田.[结论]苦豆子杂草带对有益天敌具有明显保育作用,能促进棉田捕食性天敌的发生与生物控害.

2016-2017年,利用扫网法系统调查了北疆棉田周边的非作物生境中9科13种常见植物上的食蚜蝇种群发生情况.研究发现,食蚜蝇种群密度在不同植物上有显著差异,种群发生高峰主要集中在各种植物开花期,种群消长还与这些植物上的蚜虫发生有明显跟随关系.56月,食蚜蝇在大部分植物上都有发生,但主要集中于新疆大蒜芥和罗布麻等;7-8月,在碱蓬、大麻、顶羽菊等上种群密度高;9月,主要在甘草、顶羽菊、罗布麻等上.本研究为今后充分利用棉田周边非作物生境,提升对食蚜蝇种群保育功能及棉花害虫生态控制水平提供了科学依据.

[目的]实现棉田复杂背景下棉蚜快速准确计数,提出一种先彩色分割,后自适应构元素及阈值的棉蚜计数方法.[方法]该方法基于大量棉蚜图像RGB数据进行K-means聚类建模,利用结构元素完成腐蚀去噪,针对黏连区域像素个数进行求模运算.[结果]根据图像颜色特征将噪音分为13类,蚜虫分为7类,得到其RGB值后再次分类,并分析数据建立模型实现蚜虫和噪音的彩色分割;根据统计学原理建立结构元素,对不同噪音的图像自动选择最优结构元素进行腐蚀去噪;计算黏连区域像素个数与单头蚜虫期望大小像素个数的模,实现黏连区域蚜虫计数.[结论]基于结构元素的棉蚜计数方法能有效的对棉田复杂背景下棉蚜快速准确计数,计数平均准确率为86.47％,在图像处理过程中极大降低了算法对阈值的依赖性,有效地解决了棉蚜图像黏连分割的问题,完成基于数字图像的复杂背景下棉蚜计数.

[目的]解决棉田复杂背景下棉花叶部病害快速识别问题,为提出一种快速提取棉花植株和分割棉花叶片的方法.[方法]通过棉花植株的RGB颜色特征将植株与土壤进行分离,结合形态学处理技术和彩色分割方法,将植株的茎秆去除,保留棉花叶片部分;分别使用广度搜索分割算法、分水岭分割算法和轮廓搜索分割算法,对棉花叶片图像进行分割提取.[结果]基于广度搜索的分割算法将叶片轮廓搜索出来与原图融合分离出叶片,该算法对于图像结构简单的情况分割效果较好,通过对应的drawContours函数将每个轮廓画出,再与原图定位,将叶片的完整信息也轮廓结合,实现叶片的分离.[结论]基于距离变换的分水岭分割算法存在过分割问题,基于广度搜索分割算法与边缘检测结合对于叶片结构清楚图像分割效果显著,与轮廓搜索算法相比,后者的适用性更广,提取的轮廓层次结构也清楚,分割效果最佳.

[目的]研究温度变化对多异瓢虫[Adonia variegata(Goeze)]成虫捕食棉蚜能力的影响.[方法]在17、23、29和35℃四个处理温度下,室内测定多异瓢虫成虫在不同棉蚜密度条件下的捕食量.[结果]不同温度下多异瓢虫成虫对棉蚜的捕食功能反应属于Holling-Ⅱ型.随着温度的升高,多异瓢虫成虫对棉蚜的捕食能力逐渐增加.在相同温度条件下多异瓢虫成虫对棉蚜的寻找效应随密度的增加而减小.在35℃条件下,多异瓢虫成虫的a/Th最大,捕食能力为17℃的2倍.[结论]温度对多异瓢虫的捕食量影响显著,在一定温度范围内,随温度升高,多异瓢虫成虫的捕食量明显增加.

[目的]捕食螨运动速率直接影响其捕食能力.本研究分析了5种寄主植物对捕食螨——双尾新小绥螨Neoseiulus bicaudus运动速率的影响,旨在探究双尾新小绥螨在不同寄主植物上对土耳其斯坦叶螨的捕食能力.[方法]采用数字图像处理技术,分析双尾新小绥螨雌成螨在菜豆Phaseolus vulgaris、棉花Gossypium hirsutum、番茄Solanum lycopersicum、茄子Solanum melongena和黄瓜Cucumis sativus上的运动速度,进一步采用小室观察法比较了寄主植物对双尾新小绥螨捕食功能反应的影响.[结果]双尾新小绥螨在5种寄主植物上的运动速度依次为:菜豆(0.62 cm/s)和棉花(0.60 cm/s)＞黄瓜(0.38 cm/s)和茄子(0.36 cm/s)＞番茄(0.27 cm/s).进一步捕食功能反应结果表明,在5种寄主植物上,双尾新小绥螨对土耳其斯坦叶螨的捕食量均随猎物密度的增加而升高,增加到一定程度后趋于缓和,其捕食类型均属于HollingⅡ型.双尾新小绥螨在菜豆上对土耳其斯坦叶螨的攻击系数(a)最高,为1.124;在棉花上的处理时间(Th)最短,为0.059.同时,在菜豆和棉花上的捕食能力较强,a/Th值分别为18.177和16.763;而在番茄、茄子和黄瓜上的捕食能力较弱,a/Th值分别为6.780,6.537和6.369.[结论]双尾新小绥螨在棉花和菜豆上的运动速度最快,同时捕食能力也最强.

The coexistence of species competing for resources can be facilitated by differential effects of temperature on fitness components. The coexisting cotton aphids Aphis gossypii Glover and Acyrthosiphon gossypii Mordvilko show seasonal differences in abundance in North-Western China, the former reaching higher field abundances and declining later in the season than the latter. We hypothesized that differences in responses to temperature might be the proximate mechanism driving this difference in population dynamics between the two species. Aphids from laboratory-reared colonies and directly collected from the field in early summer were used to study their development, survival and reproduction under a range of constant temperatures. Life-table parameters suggest that A. gossypii performed better than Ac. gossypii under all temperature treatments tested, and the difference tended to be strongest under high temperatures. These observations are consistent with the higher numbers and the later decline of A. gossypii in the field compared with Ac. gossypii. Our findings help in understanding the seasonal population dynamics of both species, as well as in forecasting pest trends under global warming scenarios.

双翅目潜蝇科斑潜蝇属的害虫常称潜叶蝇或斑潜蝇,其幼虫在叶片内取食为害,部分种类由于寄主范围广泛,年发生代数多,世代重叠,易产生抗药性,对设施农业生产危害严重.