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): Oviposition behaviour of Bracon brevicornis Wesmael (Hymenoptera: Braconidae) . Agric. Res. J. Kerala , 18 , 239 – 241 . Rukshana , K. and Majeed , P. P. ( 2014 ): The effectiveness of biocontrol of Opisina arenosella (Lepidoptera: Oecophoridae

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Byeon, Y. W., Tudam, M., Kim, J. H. and Choi, M. Y. (2011): Functional responses of aphid parasitoids, Aphidius colemani (Hymenoptera: Braconidae) and Aphelinus asychis (Hymenoptera: Aphelinidae). Biocontrol Science and Technology 21, 57

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A total of 36 UV-induced mutants with altered colony morphology were isolated from strain Trichoderma harzianum T334, a potential biocontrol agent against plant pathogenic fungi with the ability to produce constitutively low levels of chitinases. The level of constitutive β -1,4- N -acetyl-glucosaminidase production in standing and shaken cultures under non-inductive conditions was tested in mutants and compared to that of the parental strain. About 30% of the mutants showed significantly increased levels of enzyme production, with strain T334 col26a being the best producer. This mutant and the parental strain were subjected to in vitro confrontation assays with plant pathogenic Fusarium culmorum, Pythium debaryanum and Rhizoctonia solani strains. The mutant derivative could be characterized by significantly higher biocontrol index values than the parental strain in each experiment, suggesting, that mutants with improved constitutive extracellular chitinase secretion could be applied for biocontrol purposes against fungal plant pathogens.

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Chaetomium globosum Kunze Ex. Fries has been identified as a potential antagonist of Bipolaris sorokiniana and Ascochyta rabiei. Nine isolates of this biocontrol agent were characterized based on RAPD technique using 40 random primers of OPB and OPM series, out of which 24 primers gave a total of 356 amplification products, showing 91% polymorphism. RAPD analysis revealed that C. globosum isolates taken under study formed genetically two distinct clusters, with isolates Cg2, Cg3 and Cg4 in one cluster and the remaining isolates in another cluster, which in turn was grouped separately into two subclusters separating isolates Cg6 and Cg8 from Cg1, Cg5, Cg7 and Cg9. Similarity matrix indicated that Cg1 and Cg2 were genetically distinct as they showed only 29.4% similarity followed by Cg2 and Cg7 showing 31.1% similarity, while isolates Cg7 and Cg9 were found to be genetically similar with 68.9% similarity index.

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Laboratory studies were conducted to assess 1) the ovipositional preference of Encarsia citrina for host’s age by exposing it to 5–20-day-old scales 2) the effect of temperature (17.5, 20, 25, and 28 °C) and parasitoid density (1, 2, 3, 4, and 5 females/30 2nd instar) on host foraging efficiency of E. citrina. E. citrina significantly preferred 10-day-old scales with the highest emergence rate. Temperature had significant effect on the searching efficiency of E. citrina over the range of 17.5–28 °C. The highest rate of search was obtained at 20 °C. Although the increase in parasitoid density at 20 °C reduced the progeny production in E. citrina, due to the increase of mutual interference, it was able to distribute its progenies among the hosts more regularly. The highest values of killing power (k-value) were also obtained at 20 °C and the ratio of 4 parasitoid females/30 hosts. The shortest and longest handling time (Th) was measured at 20 and 17.5 °C, respectively. Accordingly, 20 °C is suitable condition to Encarsia reproductive and activity. E. citrina seems to be a promise candidate to control U. euonymi from late spring to early summer as well as during autumn, where the temperature is frequently around 20 °C. Therefore, parasitoid releases within this period on the early 2nd instar (10 days old) with a ratio of 1 parasitoid: 7.5 hosts have to be considered in the future biocontrol program of U. euonymi.

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.: Inhibitory furanone produced by the biocontrol agent Trichoderma harzianum . Phytochemistry 31 , 485-486 (1992). Inhibitory furanone produced by the biocontrol agent Trichoderma harzianum Phytochemistry 31 485 486 Haran, S

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The blowfly Lucilia sericata (Meigen, 1826) (Diptera: Calliphoridae) is the primary agent of cutaneous myiasis of sheep in northern Europe, southern Africa, Australia and New Zealand. As the application of chemicals has several disadvantages, alternative control measures of traumatic myiasis of livestock must be developed. In this study, the use of entomopathogenic nematodes (EPNs) as potential biocontrol agents against second instar larvae of Lucilia sericata was considered. The following nematode species were tested: Heterorhabditis bacteriophora (IS 5, HHU 1, Hmo1, HNC 1, HAZ 36, Hbrecon, HHU 2, HAZ 29, HHP 88, HHU 3, HHU 4 and HGua), Steinernema intermedia, NC513 strain of S. glaserii, S. anomali, S. riobrave, Steinernema sp. and 5 strains of S. feltiae (22, Vija Norway, HU 1, scp, and IS 6). None of the examined EPN species or strains showed larvicidal efficacy at 37°C (no killing effect was observed in the case of the two heat-tolerant strains - H. bacteriophora and S. feltiae) against L. sericata larvae. At lower temperatures (20°C and 25°C) only strainsof S. feltiae were found to be active. The overall odds ratios calculated for L. sericata maggots to contract S. feltiae nematode infection show significant (p < 0.05) effect only in the case of strains HU 1, 22 and IS 6. In the case of strains HU 1 and 22 parasitic forms of S. feltiae could be detected in the dead larvae of L. sericata. Strain IS 6 (and also Vija Norway at 20°C) penetrated and killed fly larvae, but only adult forms of the nematode occurred in the cadavers.

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record of an important agent in scales biocontrol, Pharoscymnus horni (Weise, 1900) (Coleoptera: Coccinellidae) from Iran . J. Entomology and Zoology Studies. 5 , 310 – 311 . Seago , A. E. , Giorgi , J. A. , Li , J. and Ślipiński , A

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Acta Alimentaria
Authors: M.Y. Jiang, Z.R. Wang, K.W. Chen, J.Q. Kan, K.T. Wang, Zs. Zalán, F. Hegyi, K. Takács, and M.Y. Du

. Droby , S. , Wisniewski , M. , Macarisin , D. & Wilson , C. ( 2009 ): Twenty years of postharvest biocontrol research: Is it time for a new paradigm . Postharvest Biol. Tec. , 52 , 137 – 145

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257 260 Grabenweger, G. (2003): Parasitism of different larval stages of Cameraria ohridella . BioControl 48, 671–684. Grabenweger

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