绿盲蝽触角感器的扫描电镜观察

利用扫描电镜对绿盲蝽雌雄成虫的触角形态和感器进行了观察。结果表明： 绿盲蝽触角为线形, 共4节, 即柄节、梗节和2个鞭节。触角感器共有4种, 分别为毛形感器、刺形感器、锥形感器、Böhm氏鬃毛。其中, 毛形、刺形、锥形感器各有两种类型。雌雄个体之间触角感器的类型、分布均没有明显差异。不同感器在触角各节上的数量与分布各不同。     

Testing the resource concentration hypothesis with tarnished plant bug on strawberry: density of hosts and patch size influence the interaction between abundance of nymphs and incidence of damage

Abstract. 1. Attributes of patches with strawberry plants were manipulated experimentally to assess the impact of patch size and host density on the abundance of tarnished plant bug (Hemiptera: Miridae) and incidence of fruit damage.
2. The density of nymphs per inflorescence increased with patch size and host density for some but not all generations of plant bug, providing partial support for the resource concentration hypothesis, while emphasising the importance of replicating experiments across several generations of herbivore.
3. Increasing density of nymphs with increasing patch size and host density did not translate into a high incidence of damage, which may be due to the relatively low feeding impact of nymphs in patches with numerous fruits and to the relatively high perimeter-to-area ratio in small patches resulting in a relatively high proportion of damaged fruits.
4. The decreasing proportion of damaged fruits with increasing density of fruits per patch suggests that nymphs exhibit a saturating functional response to density of strawberry fruits. Functional responses of herbivores may be a critical yet overlooked component that influences interactions between insects and their host plant. In particular, concentrated plant resources may result in increased numbers of herbivores yet sill have a negligible influence on plant damage and/or fitness.     

Functional response and mutual interference of Peristenus spretus (Hymenoptera: Braconidae), a parasitoid of Apolygus lucorum (Heteroptera: Miridae)

Peristenus spretus Chen & van Achterberg (Hymenoptera: Braconidae) is a solitary endoparasitoid, which is considered for augmentative biological control of Apolygus lucorum Meyer-Dür (Heteroptera: Miridae) in Chinese cotton fields. Since the association of P. spretus with A. lucorum was only recently discovered, the biology of the parasitoid remains unknown. In order to understand its reproductive biology, the mutual interference and functional response of P. spretus were investigated by altering either the parasitoid or the host density while keeping the other constant. In both experiments, the effects of parasitoid and host densities on parasitism, superparasitism, progeny production and sex ratio were assessed. P. spretus exhibited a Holling type II functional response to changing host densities, indicating that parasitism increases with increasing host density until the parasitoid reaches its maximum reproductive capacity. The model suggested that a single P. spretus female could parasitise a maximum of 88 nymphs per day or four nymphs per hour. Increasing the wasp-nymph ratio from 1:10 to 1:80 significantly increased the offspring production more than fivefold from ±5.8 to ±35.6; further increasing the host densities (above 80 nymphs) did not significantly increase offspring production. Strong mutual interference of foraging P. spretus females occurred only at high parasitoid densities. Parasitoids foraging alone produced an average progeny of 33.4, whereas parasitoids foraging in groups of 16 produced only 2.6. The optimal wasp-nymph ratio for mass-rearing P. spretus is 4:100, given that resources of parasitoids and nymphs are unlimited.     

Plant responses to insect herbivore damage are modulated by phosphorus nutrition

Interactions between plants and their herbivores are often multidimensional, complicating interpretation of herbivore‐impact studies. A previous study, directed toward understanding variation in incidences of flower bud abscission among cotton plants attacked by Lygus plant bugs, revealed an unanticipated correlation between levels of phosphorus nutrition and the propensity of plants to abscise developing flower buds. Here, we further investigate the relationship between phosphorus nutrition and cotton [Gossypium hirsutum Tod. (Malvaceae)] plant responses to herbivory by tarnished plant bugs, Lygus hesperus Knight (Hemiptera: Miridae). Complementary experimental approaches and survey data both suggest that levels of phosphorus nutrition falling within the normal range of variation can influence the manner by which plants respond to herbivory. In particular, higher levels of phosphorus nutrition resulted in elevated bud abscission rates when buds were damaged. Interestingly, increased levels of abscission under high‐phosphorus regimes did not translate into a decrease in overall cotton lint yield, suggesting that the ‘phosphorus effect’ may ultimately reflect how environmentally contingent differences in the allocation of vegetative vs. reproductive investments can provide parallel pathways to equal yields.     

Bioclimatic analyses of distributions of a parasitoid Peristenus digoneutis and its host species Lygus spp. in Europe and North America

• 1 Peristenus digoneutis Loan is a parasitoid of Lygus plant bugs, which was successfully introduced from Europe into North America in the 1980s for controlling native Lygus populations. Surveys confirmed that P. digoneutis populations have become established throughout eastern North America and that the spread of the parasitoid continues. For unknown reasons, previous releases of P. digoneutis in Western Canada were not successful.
• 2 A bioclimate (climex ®; Hearne Scientific Software Pty Ltd, Australia) model for P. digoneutis in North America was developed, based on climate and ecological parameters, and then validated with actual distribution records. The current distribution of P. digoneutis in eastern North America was consistent with the predicted distribution. The model suggests that P. digoneutis will probably continue its spread westwards throughout the U.S.A. along the Great Lakes.
• 3 The southern distribution of P. digoneutis is expected to be limited by hot summer temperatures, whereas its northern range is limited by the number of Lygus host generations rather than cold stress.
• 4 Peristenus digoneutis has the potential to occur in the southern parts of the prairie ecozone of western Canada; however, Ecoclimatic Index values in the prairies indicate mainly marginal or unfavourable conditions, which may explain why earlier releases of P. digoneutis in Western Canada failed.

     

绿盲蝽取食与机械损伤对棉花叶片内防御性酶活性的影响

为探明绿盲蝽Apolygus lucorum (Mayer-Dür)取食和机械损伤对不同抗性棉花叶片内主要防御酶活性的影响以及防御酶与棉花抗绿盲蝽性的关系,以棉花3个不同抗性品系为材料,室内条件下测定绿盲蝽取食和机械损伤处理后棉叶中苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)和多酚氧化酶(PPO)的活性.结果表明:对...     

棉花品种抗绿盲蝽特性的田间光谱诊断

调查了生长期14个不同棉花品种上绿盲蝽Apolygus lucorum Meyer-Dür的危害情况。亚洲棉表现为高抗,冀丰杂7号等12个品种表现为中抗,灵-17表现为敏感。田间采用ASD光谱仪对14个棉花品种生长期的冠层光谱进行了测定,发现相同品种不同时期的光谱反射率的一阶微分具有明显差异(P<0.05),在近红外717 nm波段处一阶微分光谱值与棉花抗绿盲蝽级别显著相关(R2=0.89,P=0.01),可较好的表征绿盲蝽危害指数,可利用这个波段的光谱指标对棉花品种的抗绿盲蝽特性进行初步诊断,为棉花抗盲蝽评价选育提供参考。     

新疆喀什地区牧草盲蝽为害棉花防治指标研究

【目的】害虫防治指标是害虫管理系统中进行优化决策的主要依据。本文研究了新疆棉区牧草盲蝽Lygus pratensis(Linnaeus)不同时期对棉花为害与棉花产量损失的关系,制定棉田防治指标,以期为新疆棉田牧草盲蝽防治提供理论和基础。【方法】利用二次正交旋转组合设计,建立以蕾期、花期和铃期牧草盲蝽种群数量与棉花产量损失的回归方程,并结合棉花经济允许损失率,制定棉田蕾期、花期和铃期牧草盲蝽防治指标。【结果】牧草盲蝽种群数量与棉花产量损失的回归方程:Y=12.906+5.273X1+4.780X2+2.365X3+4.588X12+3.331X22+2.910X32。蕾期牧草盲蝽成虫为害对棉花产量损失的影响最大,其次是花期和铃期。牧草盲蝽防治指标,蕾期为12头/百株、花期为20头/百株、铃期为41头/百株。【结论】本研究在棉花不同生育期的基础上,分别制定各个生育期牧草盲蝽防治指标,既简捷实用,又便于农民掌握,能更好的指导防治工作,同时可为新疆棉田牧草盲蝽防治提供理论基础。     

牧草盲蝽实时定量PCR内参基因的筛选

【目的】筛选出适合牧草盲蝽Lygus pratensis在不同条件下稳定表达的内参基因。【方法】选取编码牧草盲蝽α-微管蛋白、β-微管蛋白、肌动蛋白、延伸因子、琥珀酸脱氢酶复合体A、泛素、转录起始因子TFIID亚基、谷胱甘肽S-转移酶、核糖体蛋白L32及TATA盒结合蛋白的10条基因为候选内参基因,采用qRT-PCR技术测定其在牧草盲蝽不同性别成虫、成虫不同组织、不同龄期、对功夫菊酯不同抗性成虫、不同温度及不同杀虫剂分别处理后的成虫共6类样品中的表达量;采用BestKeeper, geNorm, NormFinder及RefFinder 4种计算程序对各候选基因的表达稳定性进行评价。【结果】依据获得的有效qRT-PCR数据前提,利用不同计算方法综合分析得出：在牧草盲蝽成虫不同组织中和对功夫菊酯不同抗性成虫中最稳定表达的内参基因均为RPL32;不同温度处理、不同性别成虫中、不同杀虫剂处理和不同龄期牧草盲蝽中最稳定表达的内参基因分别为UBQ, SDHA, β-tubulin和TAF。通过geNorm软件判断配对变异数确定的内参基因最佳数目,结合RefFinder对基因表达稳定性综合排序的结果可得：牧草盲蝽不同成虫组织中、不同性别成虫中、不同龄期、对功夫菊酯不同抗性成虫中、不同温度及杀虫剂分别处理的成虫等各组的最优内参基因组合分别为RPL32+TAF, SDHA+GST, TAF+GST+UBQ, RPL32+GST, UBQ+ACT+β-tubulin和β-tubulin+TAF+RPL32。【结论】本研究获得的牧草盲蝽在不同条件下表达最稳定及最适内参基因组合,都可用于后续的基因定量表达研究。     

Characterization of eight polymorphic microsatellite markers in the tarnished plant bug,Lygus lineolaris (Palisot de Beauvois)

A partial genomic library of the tarnished plant bug, Lygus lineolaris, enriched for microsatellite sequences was screened to identify marker loci. Eight polymorphic loci suitable for population genetic studies were identified by screening 192 field‐collected insects. The observed number of alleles ranged from four to 21 with an average of 12.25 (SE ± 1.94) while the effective number of alleles ranged from 1.23 to 11.05 with an average of 4.49 (SE ± 1.15). No linkage disequilibria or significant deviations from Hardy–Weinberg expectations were detected at any of the loci. Seven of the eight L. lineolaris microsatellite loci were transferable to Lygus hesperus.