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Genus Eurydoxa Filipjev in China is reviewed and noted for the first time. Based on the present study, two species are recognized, including rhodopa Diakonoff and advena Filipjev. All available information for the species is reviewed and provided.  相似文献   
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吴起县的沙棘面积达到12.53万hm2,全县受沙棘木蠹蛾危害的面积4647.22hm2,分布于9个乡镇,以周湾、长城两乡镇最为严重,虫口密度平均单株达15头以上,危害最重的单株虫口近70多头,幼虫啃食根干,导致根干部腐烂直至死亡。沙棘木蠹蛾的防治技术主要包括平茬更新复壮、化学防治、林分结构调整、采用灯光诱杀和性引诱剂诱杀等方法。  相似文献   
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Invasive plants are one of the greatest threats to endangered insect species and a major threat to Lepidoptera in eastern North America. We investigated the effects of the invasive shrub Chinese privet (Ligustrum sinense) and two methods (mulching or hand-felling) of removing it from riparian forests on butterfly communities and compared them to untreated, heavily invaded control plots and to “desired future condition” forests that never had extensive privet cover. Privet mulching resulted in nearly twice as many butterflies as privet felling and both treatments had more butterflies two years after privet removal than untreated control plots. Butterfly communities on control plots differed from those on the two treatments and the desired future condition forests. A number of forest characteristics were evaluated but only herbaceous plant cover (excluding privet) was positively correlated with butterfly abundance, diversity and evenness. The Carolina satyr, Hermeuptychia sosybius, was the best indicator of forests where privet had never invaded. Removing Chinese privet from riparian forests in the southeastern United States greatly improved forest habitats for butterflies and evidence suggests that butterfly communities in other temperate forests could benefit from removal of extensive shrub layers dominated by a single species.  相似文献   
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A high temperature/low oxygen pulse improves cold storage disinfestation   总被引:4,自引:0,他引:4  
Short periods of elevated temperature under controlled atmospheres (CA) effectively control insect pests. Cold treatment is also an effective non-chemical disinfestation process. If synergistic effects can be found by combining treatments, these may provide opportunities for cost reduction. Tests were performed to evaluate the tolerance of Packham's Triumph pears (Pyrus communis L.) to a range of temperatures (30–40 °C) combined with low oxygen (O2 < 1 kPa). Treatment duration was 16–48 h and was followed by 1 month storage at 0 °C under air. When held at 30 °C, pears withstood up to 30 h of hypoxia. After cold storage, pears ripened slightly faster than controls but were undamaged. A temperature of 35 °C induced slight skin browning, and 40 °C resulted in substantial skin blackening. Some treatments were also tested on survival of lightbrown apple moth (LBAM), Epiphyas postvittana (Walker). All developmental stages were subjected to either 16 h at 30 °C, or 16 h under hypoxia, or 1 month at 0 °C, or a combination of the three treatments. With all treatments combined, all eggs, larvae and adults were killed. Only 4% of the pupae produced adults and combined treatments led to an increase in pupa mortality of 38%. A combined treatment (tolerated by pears) consisting of 30 h at 30 °C under low O2 plus 1 month cold storage under air, killed 100% of LBAM pupae, and 100% of 5th instar larvae of both codling moth, Cydia pomonella (L.), and oriental fruit moth, Grapholita molesta (Busck). Implementation of such treatments would not require substantial investments for fruit industries equipped with CA storage facilities.  相似文献   
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利用显微观察并描述了鳞翅目亚麻篱灯蛾、驼波尺蛾、榆绿天蛾、雪毒蛾、灰双纹螟、尖锥额野螟、银锭夜蛾、荒夜蛾卵壳的形态特征。结果表明,不同种类蛾卵受精孔的数目;受精孔区花饰的形状、数目、排列方式;气孔的位置与排列均存在明显的差异,这些差异为卵的分类提供了依据。  相似文献   
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Indicator taxa are often proposed as efficient ways of identifying conservation priorities, but the correlation between putative indicators and other taxa has not been adequately tested. We examined whether a popular indicator taxon, the butterflies, could provide a useful surrogate measure of diversity in a closely related but relatively poorly known group, the moths, at a local scale relevant to many conservation decisions (100-101 km2). We sampled butterflies and moths at 19 sites representing the three major terrestrial habitats in sub-alpine Colorado: meadows, aspen forests, and conifer forests. We found no correlation between moth and butterfly diversity across the 19 sites, using any of five different diversity measures. Correlations across only meadow sites (to test for correlation within a single, species-rich habitat) were also not significant. Butterflies were restricted largely to meadows, where their host plants occur and thermal environment is favorable. In contrast, all three habitats contained substantial moth diversity, and several moth species were restricted to each habitat. These findings suggest that (1) butterflies are unlikely to be useful indicators of moth diversity at a local scale; (2) phylogenetic relatedness is not a reliable criterion for selecting appropriate indicator taxa; and (3) a habitat-based approach would more effectively conserve moth diversity in this landscape and may be preferable in many situations where indicator taxa relationships are untested.  相似文献   
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In contrast to many other western European countries, the knowledge about trends in the Swedish butterfly fauna is poor. We studied the effects of habitat and species characteristics on species turnover in 13 grassland sites in southern Sweden by comparing species richness and compositions at two separate occasions with an interval of 21 years. The mean number of species per site decreased from 30 to 24, with a large variation between sites. The number of extinctions was highest in sites where the proportion of trees and shrubs had increased most, but there was no detectable effect of area or of the composition of landscapes surrounding the sites. Areas protected as nature reserves had lost as many species as unprotected areas had, indicating both the importance of proper management of nature reserves and that nature reserves alone may not be enough to inhibit regional extinction of butterfly species. Species dependent on nutrient-poor conditions tended to decrease while species dependent on nutrient-rich conditions tended to increase, indicating a negative effect of increased soil nitrogen levels resulting from active fertilizing of pastures and/or atmospheric nitrogen deposition. A regular monitoring program could show whether our results are representative for Sweden or Northern Europe.  相似文献   
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