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81.
82.
Carlos Romero F. Oliveira Leda Rita D'A. Faroni Raul Narciso C. Guedes Angelo Pallini 《BioControl》2003,48(5):503-513
Recent reports of the biocontrolpotential of the mite species Acarophenaxlacunatus (Cross & Krantz) (Prostigmata:Acarophenacidae) and the lack of biologicalstudies on this regulatory agent led to thepresent study carried out under laboratoryconditions. The objective of the investigationwas to assess the host range of A. lacunatus,so far only reported as egg parasite ofRhyzopertha dominica (F.) (Coleoptera:Bostrichidae). Four Coleoptera species ofstored cereals were used: R. dominica,Tribolium castaneum (Herbst) (Tenebrionidae),Cryptolestes ferrugineus (Stephens)(Laemophloeidae) and Oryzaephilus surinamensis (L.) (Cucujidae). The highest rates of eggparasitism were observed on R. dominica and T.castaneum, leading to a significant decrease ofpopulations of both species and reduced wheatweight loss. A. lacunatus was also able toparasitize eggs of C. ferrugineus, but not ofO. surinamensis. These results indicate abroader host range of A. lacunatus thaninitially suspected and also strengthen itspossibility of use in integrated pestmanagement programs in storage environments. 相似文献
83.
The introduction of several plant pests into Europe in the 19th century with disastrous consequences called for the development
of plant quarantine measures to prevent the spread and introduction of pests of plants and plant products. With the purpose
of harmonising these measures, and of promoting measures for pest control, the International Plant Protection Convention (IPPC)
was developed to address organisms that are both directly and indirectly injurious to plants. It supplies a framework for
measures against invasive alien species according to the Convention on Biological Diversity, as far as they are plant pests.
Three examples of invasive alien species within the scope of the IPPC are given in the article: the fungus Ceratocystis fagacearum, the pinewood nematode Bursaphelenchus xylophilus and the flatworm Arthurdendyus triangulatus. In its 1997 revision, the IPPC provides for the establishment of International Standards for Phytosanitary Measures, being
acknowledged by the Agreement on the Application of Sanitary and Phytosanitary Measures of the World Trade Organisation. Standards
most important for invasive alien species are those on pest risk analysis, on requirements for the establishment of pest-free
areas, on surveillance, on pest eradication programmes, and on the import and release of exotic biological agents. Phytosanitary
regulations in the European Union (EU) have been harmonised and up to now have regulated about 300 plant pests. The requirements
also have a protective horizontal effect against the unintentional introduction of many other species, but the existing broader
IPPC mandate for alien plant pests is not fully applied by the EU regulations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
84.
Biological control of marine invasive species: cautionary tales and land-based lessons 总被引:1,自引:0,他引:1
David Secord 《Biological invasions》2003,5(1-2):117-131
Biological control (biocontrol) has successfully regulated pest populations in terrestrial agroecosystems, but it has also caused negative unintended consequences for native species. Marine biologists and resource managers have recently published a growing number of proposals to include biocontrol in integrated pest management programs in oceans, seas and estuaries. Here, I review six ecologically and taxonomically diverse case studies of marine biocontrol programs at various stages of planning and implementation. Proposals include viral or microbial control of harmful algal blooms, predatory control of the ctenophore Mnemiopsis leidyi in the Black Sea, parasitic regulation of the European green crab Carcinus maenas, castration by ciliates of the seastar Asterias amurensis in Australia, herbivory of the toxic green alga Caulerpa taxifolia in the Mediterranean by sacoglossan sea slugs, and insect biocontrol by the planthopper Prokelesia marginata to ameliorate ecological impacts of the saltmarsh cordgrass Spartina alterniflora. Where data exist, I evaluate these examples in terms of lessons marine invasion biologists can glean from the rich history of terrestrial biocontrol, and explicitly contrast agroecosystems with invaded marine habitats. Host specificity cannot be guaranteed in the marine biocontrol proposals examined. Feasible alternatives to classical biocontrol in the marine realm should be emphasized, including more investment in invasion prevention tools, early detection and eradication while invasions are small, and increased attention to native natural enemies to control exotic pests. Biocontrol in marine habitats is risky: it poses many more uncertainties and has a much sparser history than its counterpart on land. 相似文献
85.
作物抗虫种质资源的研究与应用 总被引:12,自引:0,他引:12
农业害虫给农作物产量和品质造成了重大经济损失,利用农作物抗虫特性,选育和种植抗虫品种是防治虫害最经济、有效的措施。抗虫种质资源是进行农作物抗虫育种的基础。目前,作物抗虫资源的研究涉及抗虫材料的收集、鉴定、评价、保存、利用以及抗虫种质资源创新等方面,对农作物抗虫基因的发掘与应用、抗虫品种的培育产生了积极促进作用。 相似文献
86.
87.
Development and reproduction of the predatory mite Parasitus consanguineus Oudemans et Voigts (Acari: Parasitidae) reared on a diet of first and second instars of Megaselia halterata (Diptera: Phoridae) or Lycoriella ingenua (Diptera: Sciaridae) were studied. Mites were allowed to feed on these diets until death. The developmental time of immature
stages of P. consanguineus was significantly longer when reared on L. ingenua than on M. halterata larvae (8.3 vs. 7.9 days, respectively). Survival to adulthood of P. consanguineus reared on L. ingenua or M. halterata larvae was 63 and 49%, and mite fecundity was 17.8 and 12.3 eggs/female, respectively. Adult females reared on L. ingenua lived on average 6.9 days, whereas those reared on M. halterata lived for 5.7 days. Mite survival, female longevity and fecundity were significantly different among the two diet types. 相似文献
88.
S. B. Hu P. Liu X. Z. Ding L. Yan Y. J. Sun Y. M. Zhang W. P. Li L. Q. Xia 《Applied microbiology and biotechnology》2009,82(6):1157-1167
Previous studies revealed that chitinase could enhance the insecticidal activity of Bacillus thuringiensis and it has been used in combination with B. thuringiensis widely. However, the expression of B. thuringiensis chitinase is rather low and needs induction by chitin, which limits its field application. It would make sense to constitutively
express the chitinase at a sufficiently high level to offer advantages in biological control of pests. In this study, a signal
peptide-encoding sequence-deleted chitinase gene from B. thuringiensis strain 4.0718 under the control of dual overlapping promoters plus Shine–Dalgarno sequence and terminator sequence of cry1Ac3 gene was cloned into shuttle vector pHT315 and introduced into an acrystalliferous B. thuringiensis strain Cry−B. The recombinant plasmid was stably maintained over 240 generations in Cry−B. Chitinase was overexpressed within the sporangial mother cells in the form of spherical crystal-like inclusion bodies.
The chitinase inclusions could be solubilized and exhibit chitinolytic activity in 30 mmol l−1 Na2CO3–0.2% β-mercaptoethanol buffer at a wide range of alkaline pH values, and what’s more, the chitinase inclusions potentiated
the insecticidal effect of Cry1Ac protoxin when used against larvae of Spodoptera exigua and Helicoverpa armigera. 相似文献
89.
90.
In silkworms, sex-limited strains are either obtained spontaneously or induced by X-rays or gamma rays. When a fragment of an autosome carrying a dominant allele of those genes responsible for certain characters is translocated onto a W chromosome, the female of the successive generations will express these phenotypic characters and sex discrimination can be facilitated. Gensei-kouken strains are sex-limited strains of silkworms developed by irradiating the pupae with gamma rays, by which a portion of the second chromosome is translocated onto the W chromosome. In these improved strains, the females are yellow-blooded and spin yellow cocoons. By using the EST-cDNA clones mapped on the Z chromosome, we identified the sex according to the polymorphic banding pattern or intensity of the signals. Furthermore, by using the clones on the second chromosome, the region of the second chromosome translocated onto the W chromosome was also defined. In both the A95 and A 96 strains selected for the present study, only the mid-portion of the second chromosome was translocated. The differences in length of the fragments translocated in these strains are discussed. 相似文献