oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Interspecific interactions between Cotesia plutellae and Oomyzus sokolowskii, two major parasitoids of diamondback moth, Plutella xylostella
小菜蛾主要寄生性天敌——菜蛾绒茧蜂与菜蛾啮小蜂间的相互作用

SHI Zuhua,LIU Shusheng,
施祖华
,刘树生

应用生态学报 , 2003,
Abstract: The interspecific interactions between Cotesia plutellae (Kurdjumov) (Hym.: Braconidae) and Oomyzus sokolowskii (Kurdjumov) (Hym.: Eulophidae) were investigated at 28 degrees C in laboratory, by exposing the 3rd instar larvae of diamondback moth, Plutella xylostella L. (Lep.: Plutellidae) to two parasitoids concurrently, or to either species alone, and by exposing the host larvae already exposed to one species to another species. Compared with those exposures of host larvae to either one species at a time, the parasitism rates by C. plutellae were not reduced by the presence of O. sokolowskii, but the rates of parasitism by O. sokolowskii were significantly reduced by the presence of C. plutellae, when the host larvae were exposed to the two species of parasitoid concurrently. No significant differences were found between the parasitism rates done by the two species together, and those done by either one of the two species alone. When host larvae were exposed to O. sokolowskii after exposure to C. plutellae, the successful parasitism rates by C. plutellae were unaffected, while the parasitism rates by O. sokolowskii were only 8-13%. However, O. sokolowskii could parasitize the old larvae of C. plutellae developed inside host larvae. Cotesia plutellae could parasitize the host larvae parasitized previously by O. sokolowskii, and some individuals of C. plutellae in these multiparasitized hosts could develop normally and survive to adult emergence. When O. sokolowskii wasps were exposed to healthy host larvae and host larvae parasitized by C. plutellae, they preferred to parasitize the healthy ones. These results suggest that C. plutellae is the stronger competitor, but its competition capacity will be reduced by the parasitism by O. sokolowskii.
Mortality of Plutella xylostella (Lepidoptera, Plutellidae) by parasitoids in the Province of Santa Fe, Argentina
Bertolaccini, Isabel;Sánchez, Daniel E.;Arregui, María C.;Favaro, Juan C.;Theiler, Natalia;
Revista Brasileira de Entomologia , 2011, DOI: 10.1590/S0085-56262011005000029
Abstract: mortality of plutella xylostella (lepidoptera, plutellidae) by parasitoids in the province of santa fe, argentina. plutella xylostella (linnaeus, 1758) (lepidoptera, plutellidae) larvae cause severe economic damage on cabbage, brassica oleracea l. variety capitata (brassicaceae), in the horticultural fields in the province of santa fe, argentina. overuse of broad spectrum insecticides affects the action of natural enemies of this insect on cabbage. the objectives of this work were to identify the parasitoids of p. xylostella and to determine their influence on larva and pupa mortality. weekly collections of larvae and pupae were randomly conducted in cabbage crops during spring 2006 and 2007. the immature forms collected were classified according to their developmental stage: l1 and l2 (ls = small larvae), l3 (lm = medium larvae), l4 (ll = large larvae), pre-pupae and pupae (p). each individual was observed daily in the laboratory until the adult pest or parasitoid emergence. we identified parasitoids, the number of instar and the percentage of mortality of p. xylostella for each species of parasitoid. parasitoids recorded were: diadegma insulare (cresson, 1875) (hymenoptera, ichneumonidae), oomyzus sokolowskii (kurdjumov, 1912) (hymenoptera, eulophidae), cotesia plutellae (kurdjumov, 1912) (hymenoptera, braconidae) and an unidentified species of chalcididae (hymenoptera). besides parasitoids, an unidentified entomopathogenic fungus was also recorded in 2006 and 2007. in 2006, the most successful parasitoids were d. insulare and o. sokolowskii, while in 2007 only d. insulare exerted a satisfactory control and it attacked the early instars of the pest.
New records of natural enemies of Plutella xylostella (L.) (Lepidoptera: Plutellidae) in Pernambuco, Brazil
Silva-Torres, Christian S A;Pontes, Itillio V A F;Torres, Jorge B;Barros, Reginaldo;
Neotropical Entomology , 2010, DOI: 10.1590/S1519-566X2010000500028
Abstract: we report the occurrence of natural enemies of plutella xylostela (l.) in organically farmed kale in pernambuco, brazil. seven natural enemies were observed parasitizing or preying on larvae and pupae of p. xylostella - three parasitoids: cotesia plutellae kurdjumov (hym.: braconidae), conura pseudofulvovariegata (becker) (hym.: chalcididae) and tetrastichus howardi (olliff) (hym.: eulophidae), and four predators: cheiracanthium inclusum (hentz) (araneae: miturgidae), pheidole sp.westwood (hym.: formicidae), nymphs and adults of podisus nigrispinus (dallas) (hem.: pentatomidae), and one unidentified species of solitary wasp. beyond recording these natural enemies, data on predation of p. xylostella larvae in the field and laboratory by c. inclusum are presented.
Development and Ultrastructure of Cotesia plutellae (Kurdjumov) teratocytes
菜蛾盘绒茧蜂畸形细胞发育及其超微形态结构

白素芬,陈学新,程家安,符文俊,何俊华
浙江大学学报(农业与生命科学版) , 2002,
Abstract: 首次以菜蛾盘绒茧蜂Cotesiaplutellae(Kurdjumov)]—小菜蛾Plutellaxylostella(Linnaeus)]为体系研究了畸形细胞的发生和发育.结果表明,畸形细胞来源于卵的浆膜层;雌蜂产卵后33~36h,幼蜂孵化时,每胚胎平均释放192个畸形细胞;畸形细胞的直径可随寄生日龄的增加,由初始的(15.31±3.06)μm,增大到(63.25±12.65)μm,最大可达118.75μm;但其数目却呈明显下降的趋势.扫描电镜显示:畸形细胞表面覆有微绒毛,4日龄比1日龄的更长、更密,预示着强的吸收和分泌功能.透射电镜显示:成熟的畸形细胞细胞核树状分枝明显、较初形成的细胞含有更多的内质网和丰富的线粒体.发育后期,溶酶体大量出现,且糖原、脂滴的积累增加,这表明畸形细胞代谢活动旺盛,具有合成和分泌蛋白质的能力.本文对畸形细胞的发生来源进行了探讨.
Biological Study of Plutella xylostella (L.) (Lep: Plutellidae) and Its Solitary Endoparasitoid, Cotesia vestalis (haliday) (Hym. Braconidae) under Laboratory Conditions  [PDF]
M. Alizadeh,G.R. Rassoulian,J. Karimzadeh,V. Hosseini- Naveh
Pakistan Journal of Biological Sciences , 2011,
Abstract: Plutella xylostellae (L.) (Lep: Plutellidae), is a destructive pest of brassicaceous crops in the world. Cotesia vestalis (Haliday) is one of most important biological control agents of P. xylostella in the world and Iran. Both of P. xylostella and C.vestalis biology were carried out in laboratory condition. Results showed that development time of immature stages of P. xylostella including egg, Instar I, Instar II, Instar III, Instar IV, prepupa, pupa were 2.390.17, 2.180.17, 2.060.28, 2.140.14,2.540.12, 0.400.12 and 4.230.23 days, respectively. Longevity of female and male were 28.260.05 and 30.220.05 days. By dissecting the parasitized larvae, the egg incubation period of C. vestalis was recorded 1.730.06 days. In long-term oviposition trials, females laid eggs on P. xylostella larvae for up to 10 days. Larval development of the parasitoid in host only required 6.47 days: the first instar larva required 3.250.047 days; the second instar larva needed 2.780.1 days and the third instar larvae exited the host and pupated in, 0.40.07 days. Prepupal and pupal period of wasp were 1.9.0.06 and 2.130.09 day, respectively. Unmated female and male longevity of wasp were 16.830.37, 16.250.17 and sex ratio is male-biased. When a mixed group and isolated of instars were presented for parasitoid, the 2nd and 3rd instar larvae were so preferred and the 4th instar was less attractive for selection. In choice experiment, the percentage parasitism of 2nd, 3rd and 4th instars was 78.58, 69.94 and 4.36%, respectively. The rapid oviposition rate, short life duration and high percentage parasitism increases parasitoid potential for suppression of host population. Present results suggest that C. vestalis has considerable potential as a biological control agent for P. xylostella.
Effects of host plant on the oviposition preference of Plutella xylostella ( L.) and host- selection behavior of Cotesia plutellae (Kurdjmov).
寄主植物对小菜蛾产卵选择性及菜蛾绒茧蜂寄主选择行为的影响

JIANG Li-hui,WANG Dong,LIU Shu-sheng,
江丽辉
,王栋,刘树生

浙江大学学报(农业与生命科学版) , 2001,
Abstract: The ovipositional preference of the diamondback moth, Plutella xylostella (L.) between different Brassica vegetable plants and the host selection by Cotesia plutellae (Kurdjmov) between host larvae on different Brassica plants were studied. With the presence of both the Chinese cabbage, B. campestris L. ssp. pekinensis, the common cabbage, Brassica oleracea L. var. capitata, P. xylostella, moths laid three times as many eggs on the former as that on the latter plants. When C. plutellae wasps were provided with equal numbers of larvae of P. xylostella on both species of plants in one area, parasitism rate of hosts on B. campestris was almost five times that on B. oleracea. The possible effects of infochemicals from the Brassica plants on the oviposition preference of P. xylostella and on the host selection by C. plutellae were discussed.
Intera??o de Metarhizium anisopliae (Metsch.) Sorok., Beauveria bassiana (Bals.) Vuill. e o parasitóide Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae) sobre larvas da tra?a-das-crucíferas, Plutella xylostella (L.) (Lepidoptera: Plutellidae)
Santos Jr., Hugo J.G. dos;Marques, Edmilson J.;Barros, Reginaldo;Gondim Jr., Manoel G.C.;
Neotropical Entomology , 2006, DOI: 10.1590/S1519-566X2006000200013
Abstract: chemical insecticides are broadly applied to control diamondback moth, plutella xylostella (l.). diamondback moth is a major pest of cruciferous worldwide, and resistance of this pest to insecticide has been often reported. thus, this research investigated the interactions among the fungi metarhizium anisopliae (metsch.) sorok., beauveria bassiana (bals.) vuill., and the larval-pupal parasitoid oomyzus sokolowskii (kurdjumov) before and after application of the fungi on dbm larvae offered to the parasitoid. the experiment was carried out at 26 ± 1oc, 75 ± 5% rh and 12h photophase using a completely randomized design, with eight treatments with six replications each. the isolates e9 of m. anisopliae and esalq 447 of b. bassiana, were used at the concentration of 107 conidia ml-1. the results showed that m. anisopliae and b. bassiana reduced the parasitism of p. xylostella by o. sokolowskii. additive effects were found on the mortality of p. xylostella with the different combinations among the fungi and parasitoid, except for the treatment b. bassiana inoculated 24h before exposition of the larvae to o. sokolowskii. the isolates were more efficacious when applied after exposition of the larvae to the parasitoid. the efficiency of o. sokolowskii was negatively influenced by the presence of the fungi, mainly when the fungi were applied 24h before diamondback's larvae were exposed to the parasitoid. the association of the fungi with the parasitoid presents potential to be tested in field. the use of these natural enemies in the integrated management of p. xylostella may economically improve the cabbage productive system, especially for organic farming.
The effect of host age on biological characteristics of Cotesia plutellae
寄主龄期对菜蛾绒茧蜂生物学特性的影响

LI Yuan xi,LIU Shu sheng,
李元喜
,刘树生

浙江大学学报(农业与生命科学版) , 2001,
Abstract: The effects of larval instars and ages of Plutellae xylostella at initial parasitization on developmental time, rate of cocoon formation, and parasitic capacity of resultant female wasp of Cotesia plutellae , were observed. The results showed that the development of egg and larva of parasitoid initially parasitizing in the 3rd instar larva was faster than development of those initially parasitizing in the 2 nd and the 4 th instars larvae. The rate of cocoon formation and parasitic capacity of resultant female wasps were also higher in former, indicating that the 3 rd instar larva of P. xylostella was more suitable than the 2 nd and the 4 th instars larvae for C. plutellae , though host age at parasitization had no effect on the emergence rate of parasitoids. In all host instars and ages tested, there were some parasitized individuals that died before the parasitoid larva matured and ate out of the host. For host larvae initially parasitized at the 2 nd and the 3 rd instars, these deaths occurred mainly during larval development; for those larvae initially parasitized at the 4 th instar, many deaths occurred during pupal development. When host larvae were initially parasitized at the 3 rd day of the 4 th instar, 62.5% of parasitized larvae died at the pupal stage. The relationship between suitability of host age and oviposition preference of parasitoid was also discussed.
Parasitoid and Parasitization of Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) in South Sumatera  [PDF]
SITI HERLINDA
HAYATI Journal of Biosciences , 2005,
Abstract: Surveys from May 2003 to January 2004 in South Sumatera were conducted to determine parasitoid attacking Plutella xylostella (L.) and to estimate P. xylostella parasitization by the parasitoids. The eggs and the larvae of P. xylostella were collected from brassicaceous crops, i.e. mustard, Indian mustard, and cabbage. Six parasitoids found were Trichogrammatoidea cojuangcoi Nagaraja (Hymenoptera: Trichogrammatidae), Cotesia plutellae (Kurdj.) (Hymenoptera: Braconidae), Diadegma semiclausum Hellen (Hymenoptera: Ichneumonidae), Oomyzus sokolowskii (Kurdj.) (Hymenoptera: Eulophidae), Tetrastichus (Hymenoptera: Eulophidae), and a ceraphronid wasp (unidentified species). Trichogrammatoidea cojuangcoi parasitized P. xylostella eggs, however, the others parasitized the larvae except the ceraphronid wasp. In South Sumatera, the ceraphronid wasp was reported for the first time parasitizing D. semiclausum pupae, and its parasitization reached 6.2%. Oomyzus sokolowskii and Tetrastichus were found in this area for the first time, as well. In the highland, D. semiclausum was the most abundant compared to the others where its parasitization reached 79.2%. In the lowland P. xylostella larvae was mainly attacked by C. plutellae with the parasitization reaching 64.9%. In the dry and rainy seasons, the parasitization was mainly exerted by T. cojuangcoi (77.0%) and D. semiclausum (79.2%).
Seletividade fisiológica de inseticidas aos inimigos naturais de Plutella xylostella (L.) (Lepidoptera: Plutellidae) em brássicas Insecticide physiological selectivity to natural enemies of Plutella xylostella (L.) (Lepidoptera: Plutellidae) in Brassicae  [cached]
Leandro Bacci,Marcelo Coutinho Pican?o,ézio Marques da Silva,Júlio Cláudio Martins
Ciência e Agrotecnologia , 2009, DOI: 10.1590/s1413-70542009000700058
Abstract: A conserva o de inimigos naturais é um componente fundamental no manejo integrado de pragas. Neste trabalho, estudou-se a seletividade de sete inseticidas usados no manejo de Plutella xylostella (L.) (Lepidoptera: Plutellidae) ao parasitóide Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae) e aos predadores Discodon sp. (Coleoptera: Cantharidae) e Lasiochilus sp. (Hemiptera: Anthocoridae). Os organofosforados metamidofós e paratiom metílico e o carbamato carbaril foram altamente tóxicos aos três inimigos naturais estudados. Dimetoato apresentou seletividade em favor do Discodon sp., na dose e subdose. O inseticida acefato apresentou alto impacto ao Discodon sp., no momento da aplica o e seu efeito foi reduzido com a metade da concentra o do princípio ativo. Deltametrina apresentou seletividade à O. sokolowskii nas duas dosagens. Já permetrina foi seletiva a Lasiochilus sp., somente na subdose. Discodon sp. foi mais tolerante à dose e subdose do dimetoato e à subdose do acefato do que O. sokolowskii e Lasiochilus sp. O predador Lasiochilus sp. foi mais tolerante à dose e subdose da permetrina do que O. sokolowskii e Discodon sp. O parasitóide O. sokolowskii foi mais tolerante à dose e subdose da deltametrina do que Lasiochilus sp. e Discodon sp. Os resultados desta pesquisa foram obtidos em condi es de exposi o extrema, portanto indicam que os inseticidas seletivos possivelmente n o ser o prejudiciais aos inimigos naturais, em condi es de campo. The conservation of natural enemies is a fundamental component in the integrated pest management. In this work, one studied the selectivity of seven insecticides, used in the management of Plutella xylostella (L.) (Lepidoptera: Plutellidae), to the parasitoid Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae), and to the predators Discodon sp. (Coleoptera: Cantharidae) and Lasiochilus sp. (Hemiptera: Anthocoridae). The organophosphates methamidophos and methyl parathion, and the carbamate carbaryl showed high toxicity to the three natural enemies studied. Dimethoate showed selectivity in favor of Discodon sp. in the dose and sub-dose. The insecticide acephate showed a high impact on Discodon sp. at the time of the application, and its effect was reduced with half of the concentration of the active ingredient. Deltamethrin showed selectivity to O. sokolowskii in both dosages. Permethrin was selective to Lasiochilus sp. only in the sub-dose. Discodon sp. was more tolerant to the dose and sub-dose of dimethoate and to the sub-dose of acephate than O. sokolowskii and Lasiochilus sp. The predator
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.