A review of the pest management situation in mango agroecosystems

Integrated pest management programs for mango must be based on sampling and on economic thresholds, and must take into account the effects of cultural practices, horticultural sprays and disease control on pest and natural enemy interactions. An analysis of the mass of information available on the different mango pests,viz., fruit flies(Bactrocera sp.,Ceratitis sp.,Anastrepha sp.), mango seed weevil(Sternochetus mangiferae), thrips(Frankliniella spp.), gall midges(Procontarinia sp.), scales, mites and mealybugs is given, as well as different examples for future entomological research.     

Re-test of Rhinocyllus conicus host specificity, and the prediction of ecological risk in biological control

Biological control is proposed as an ecological strategy to manage the threat of invasive plants, especially in natural areas. To pursue this strategy, we need to know that the host specificity criteria used to evaluate ecological risk with deliberate introduction of an exotic insect for biocontrol are sufficient to predict potential impact on native species. Host specificity is defined by adult feeding and oviposition preferences and larval development. One way to evaluate the criteria is to re-examine case histories where ecological effects are recorded, such as that of Rhinocyllus conicus Frölich. This flower head weevil, released in North America in 1968 to control exotic thistles like Musk thistle (Carduus nutans L), is now reducing seed production by multiple native North American thistle species (Cirsium spp.), and local population density of Platte thistle (Cirsium canescens Nutt.). We hypothesized that host specificity of R. conicus has changed since pre-release testing, providing an explanation for the unexpected magnitude of the documented ecological effects. Instead, when we re-tested host specificity of weevils naturalized over 28 generations, we found that host specificity has not changed. Naturalized adults of R. conicus showed strong feeding and oviposition preference for Musk thistle over Platte thistle. In addition, larval development by these weevils was faster and more successful (to larger size) on Musk thistle than on Platte thistle. Thus, our results indicate that a change in host specificity cannot explain the unexpectedly large build-up of R. conicus and significant ecological effect on Platte thistle. We conclude that accurate prediction of the potential level of impact on native host plants in the field requires further ecological information in addition to host specificity.     

Aerially applied methylcyclohexenone-releasing flakes protect Pseudotsuga menziesii stands from attack by Dendroctonus pseudotsugae

We tested methylcyclohexenone (MCH), an anti-aggregation pheromone for the Douglas-fir beetle (Dendroctonus pseudotsugae), for protection of Douglas-fir (Pseudotsuga menziesii) stands by applying MCH-releasing polymer flakes by helicopter twice during summer 2006 to five 4.05-ha plots in the State of Washington, USA. Five similar plots served as untreated controls. We assessed D. pseudotsugae flight into study plots using baited pheromone traps, and tallied D. pseudotsugae attack rates on all P. menziesii trees in 2005 and 2006. We also measured stand basal area and incorporated that as an explanatory variable in the analysis. Significantly fewer D. pseudotsugae were trapped in treated plots than in control plots, and significantly fewer P. menziesii trees were attacked in treated plots than in control plots. The attack rate in untreated stands was nearly 10 times that of treated plots, and stands with higher basal area were significantly more likely to be attacked by D. pseudotsugae than were stands of lower basal area. Attack rates in 2006 and 2005 were significantly correlated, regardless of treatment.     

大兴安岭林区白毛树皮象生物学特性初步研究

在大兴安岭塔河地区白毛树皮象２年一代，老熟幼虫及成虫分别在伐根及林内桔枝落叶层中越冬。成虫主要危害落叶松及樟子松的主梢及１－３年生侧枝，啃食其嫩梢，嫩叶，韧皮部及顶芽。研究表明，该虫的发生与采伐迹地的年限，伐根与林缘的距离，以及林分周围的环境等均有密切关系。     

危害沙棘种子的新象虫—沙棘象

危害沙棘(Hippophae rhamnoides L.)种子的害虫——沙棘象,隶属于象虫科(Curculionidae)象虫属(Curculio Linnaeus)为一新种。分布于陕北、渭北、关山等地,严重影响沙棘种子产量和果实利用价值。模式标本保存于中国科学院动物研究所。     

云南省象甲科研究概况

中国象甲分类学家赵养昌、陈元清奠定了云南省象甲分类学基础．云南省象甲系统分类工作薄弱的原因在于国内相对落后的象甲分类研究水平和云南省象甲分类研究人员的严重不足．到2002年，分布于云南省的象甲科昆虫已知共计145种，隶属14亚科56属．云南省象甲应用基础研究主要集中在危害杧果、松树及板栗的重要类群上．学名误用、中文名不统一的现象在已有研究中比较普遍．一些具有重要经济意义的象甲种类鉴定不准，不利于云南省林业发展及重大害虫的防治．     

进口原木截获松皮双凸象的鉴定及其风险

本文提供了福建省莆田出入境检验检疫局从来自澳大利亚澳洲辐射松原木截获的松皮双凸象的形态鉴定特征,其寄主植物种类为多种松属和杉属植物,其幼虫在树皮下危害,成虫和幼虫均易随原木远距离传播扩散。松皮双凸象对我国南方针叶树构成一定威胁,对从澳大利亚进口的针叶树原木需加强检疫以防止其入侵危害。     

Macroinvertebrates in North American tallgrass prairie soils: effects of fire, mowing, and fertilization on density and biomass

The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.