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51.
桉树(Eucalyptusspp.)原产于澳大利亚、巴布亚新几内亚、印度尼西亚。桉树具有生长快、适应性强、用途广等特性,普遍受到人们的青睐,全世界已有90多个国家引种了桉树,我国引种桉树已有100多年的历史[1]。1985年,我国与澳大利亚合作研究桉树的栽培与利用后[2],桉树在我国的营造面积迅速扩大,1988年桉树面积为40万hm2,1998年达60万hm2。随着桉树纯林面积的不断扩大,一些引种桉树历史较久的地区,其虫害问题日益突出。广东为我国南方的门户,国际交往频繁,对防止危险性害虫的入侵具… 相似文献
52.
A ten-year study consisting of nine field experiments was conducted to evaluate alfalfa (Medicago sativa L.) for resistance to larval feeding by the alfalfa weevil (Hypera postica
Gyllenhal). The results were consistent over years and experiments. Only one source of alfalfa germplasm, designated Starnes, showed resistance to larval feeding in the field under natural infestations of the weevil. The cultivars Team, Arc, and Liberty have been developed from this germplasm source. The only effective method of selection for field resistance to the weevil was field selection under natural weevil infestations. Selection was based on low larval feeding on spaced plants. After six generations of such selection the Starnes germplasm showed only one-third as much defoliation as did the check cultivars. The heritability of the weevil resistance was moderately high. Field resistance was transferred to other strains through hybridization; hybrids were intermediate to the resistant and susceptible parents. Resistance was stable.Laboratory and greenhouse efforts to breed alfalfa weevil resistant alfalfa-using such techniques as adult cotyledon-nonpreference tests, adult leaf-feeding tests, larval-growth and survival tests, oviposition-stimulus tests, and oviposition-nonpreference tests-have failed to produce field resistance.Paper No. 5308 of the Journal series of North Carolina Agricultural Experiment Station, Raleigh, N. C., in cooperation wich ARS, USDA. Received 15 June 1977. 相似文献
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草坪草抗虫性试验及其昆虫调查与防治 总被引:2,自引:0,他引:2
对11种冷季型草坪草进行了抗虫性试验。结果,全星黑麦草、德比黑麦草、帝王黑麦草、猎狗高羊茅、爱瑞高羊茅、爱肯尼早熟禾抗虫性较强。在草坪草中共发现41种昆虫,已初步鉴定出30种。其中,草二叉蚜和黄线绿夜蛾为害严重,采用50%辛硫磷乳油2000倍液喷雾,防治效果分别为100%和95.5%。 相似文献
55.
沂蒙山区杞柳害虫记述 总被引:2,自引:0,他引:2
近4年来的研究,记载了为害沂蒙山区杞柳的害虫(害螨),共计115种,分属于昆虫纲和蛛形钢,6目,31科。 相似文献
56.
26种昆虫体内的1-脱氧野尻霉素含量测定 总被引:1,自引:2,他引:1
为发掘新的富含1-脱氧野尻霉素(DNJ)的昆虫资源,共测定了26种昆虫体内的DNJ含量。除家蚕(Bombyxmori)之外,野桑蚕(Bombyx mandarina)、桑蟥(Rondotia menciana)、桑尺蠖(Phthonandria atrineata)、桑螟(Diaphaniapyloalis)等4种仅取食桑叶的单食性或寡食性昆虫也富含DNJ,其中桑蟥和桑尺蠖幼虫中的DNJ质量分数分别为1.0648%±0.1134%、0.5138%±0.0083%,高于家蚕幼虫中的DNJ含量(0.4238%±0.0108%),并且桑尺蠖春季越冬代幼虫及其室内桑叶饲育的第1代幼虫和蛹、成虫均含有DNJ,具有开发利用价值。从桑园采集的兼性食桑昆虫中,人纹污灯蛾(Spilarectia subcarnea)、美国白蛾(Hlyphantria cunea)、大造桥虫(Ascotissele naria)、黄斑星天牛(Anoplophora nobilis)等4种昆虫的幼虫中含有微量DNJ,而褶翅尺蠖(Zamacra excauvata)、枣尺蠖(Sucra jujuba)、桑毛虫(Euproctis similis xanthocampa)幼虫和桑天牛(Apriona ger-mari)成虫中不含DNJ。豆天蛾幼虫(Clanis bilineata)等13种非食桑昆虫体内均不含DNJ。研究结果也提示取食桑叶的昆虫对DNJ的富集能力存在很大差异。 相似文献
57.
Summary In Hungary the bird cherry-oat aphid (Rhopalosiphum padi L.) is the most frequent aphid species in winter wheat (Triticum aestivum L.). Estimations of infestation by R. padi as well as measurements of grain yield and thousand-kernel mass were carried out in 26 winter wheat genotypes in conditions of naturally infested and not infested (protected) control plots. The experiment was performed in isolated conditions in two field cages covered by nets. The aphids overwintered on wheat and got into cage, extremely quickly multiplied, therefore there was no need to apply any artificial aphid infestation. Highly significant differences were demonstrated among genotypes in infestation severity of R. padi as well as in losses of grain yield and thousand-kernel mass. The most resistant variety GK Zombor had 25% infestation, and the most susceptible one GK Lili had 79.2%. The reduction of grain yield of the most tolerant genotypes (GK Korány, Downy, Mv 4, Jubilejnaja 50, Mv 8, GK Kincsö and GK Zombor) was 26–33%, and that of thousand-kernel mass was 23–30%. The most sensitive genotypes (GK Lili, GK Örzse, GK Koppány and Mv 13) suffered 58–63% losses in yield, and 40–50% in thousand-kernel mass. A close correlation was found between infestation of R. padi in different wheat genotypes and losses of grain yield (r=0.7572, P<0.001). Also there were tolerance differences among genotypes even within the same level of infestation. The reductions of thousand-kernel mass correlated very closely with the reductions of grain yield (r=0.9212, P<0.001), that makes screening possible by reductions of thousand-kernel mass. These results have found application in breeding. The leaf pubescence of the varieties studied did not generally influence the infestation by R. padi. 相似文献
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59.
印度谷螟是松花粉的重要仓储害虫,为有效控制仓储害虫,确保产品质量安全,进行了干燥、过筛、灭菌及破壁等松花粉产品主要工艺过程防控印度谷螟的试验。结果表明:在松花粉产品加工流程中,采用180目以上筛网过筛,49 ℃、120 min加温干燥,12 kGy 60Coγ辐照灭菌,机械破壁或压片成型,7 g·m-3、6.5 h硫酰氟熏蒸或-8 ℃、24 h冷冻贮藏等任一工艺处理,都能防杀印度谷螟卵或幼虫。各措施组合应用能有效防控印度谷螟侵入或危害,且经济、实用和安全。 相似文献
60.