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Appl. Environ. Microbiol. 1999 65 3850 3854 Khan, M.R. 2006a. Biological control of cereal

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Pot experiments using loamy soil were conducted to evaluate the effect of irrigation with industrial effluents on growth, uptake on growth, uptake of nutrients and yield of wheat (Triticum aestivumGiza 164) as a monocot and faba beans (Vicia fabaGiza 461) as a dicot plant. Also, irrigation by industrial effluents in combination with vesicular-arbuscular mycorrhiza (VAM) was used in trying to use a biological control to overcome the harmful effects of heavy metals pollution. Irrigation of plants with industrial effluents leads to marked changes in growth criteria depending on plant and/or the stage of growth. Industrial wastewater led also to marked changes in total carbohydrates and nitrogen in both shoots and roots. On the other hand, combination of industrial waste water with VAM caused an increase in the total carbohydrates and total nitrogen in shoots and roots of both wheat and bean plants. The yield components in wheat and bean were significantly increased with industrial effluents, but the biochemical concentrations were different. In wheat, the carbohydrate concentrations were increased, but protein- N and total-N were decreased, however mineral contents, especially ZN were increased. The reverse response was recorded with VAM. For bean the opposite occurred. Generally, bean plants were more sensitive to pollution with heavy metals, than those of wheat however this could influence be overcome by using VAM with irrigation.

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The need for more environmentally sound strategies of plant protection has become a driving force in physiological entomology to combat insect pests more efficiently. Since neuropeptides regulate key biological processes, these “special agents” or their synthetic analogues, mimetics, agonists or antagonists may be useful tools. We examined brain-suboesophageal ganglia and corpora cardiaca-corpora allata complexes of the cabbage moth, Mamestra brassicae , in order to obtain clues about possible peptide candidates which may be appropriate for the biological control of this pest. With the aid of bioassays, reversed phase high performance liquid chromatography, and mass spectrometry, five neuropeptides were unequivocally identified and the presence of a further three were inferred solely by comparing mass spectra with known peptides. Only one neuropeptide with adipokinetic capability was identified in M. brassicae . Data from the established homologous bioassay indicated that the cabbage moths rely on a lipid-based metabolism which is aided by an adipokinetic hormone (viz. Manse-AKH) that had previously been isolated in many different lepidopterans. Other groups of neuropeptides identified in this study are: FLRFamides, corazonin, allatostatin and pheromonotropic peptide.

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Acta Microbiologica et Immunologica Hungarica
Authors: L. Kredics, Zsuzsanna Antal, A. Szekeres, L. Manczinger, Ilona Dóczi, F. Kevei, and Elisabeth Nagy

Species belonging to the filamentous fungal genus Trichoderma are well known as potential candidates for the biological control of plant pathogenic fungi and as cellulase producers of biotechnological importance. Several data were published in the last decade also about the clinical importance of this genus, indicating that Trichoderma strains may be potential opportunistic pathogens in immunocompromised patients. However, there is a lack of information about the potential virulence factors of clinical Trichoderma strains. This study was designed to examine the extracellular proteolytic enzymes of six clinical T. longibrachiatum isolates. Supernatants from induced liquid cultures of the examined strains were screened for proteolytic enzyme activities with 11 different chromogenic p-nitroaniline substrates. The production of trypsin-like, chymotrypsin-like and chymoelastase-like protease activities cleaving N-Benzoyl-L-Phe-L-Val-L-Arg-p-nitroanilide, N-Succinyl-L-Ala-L-Ala-L-Pro-L-Phe-p-nitroanilide,and N-Succinyl-L- Ala-L-Ala-L-Pro-L-Leu-p-nitroanilide, respectively, was common among the strains examined. Separation of trypsin- and chymotrypsin-like activities by column chromatography revealed, that both systems are complex consisting of several isoenzymes. The pH-dependence of these two protease systems was also studied. Based on the results, the different isoenzymes seem to have different optimal pH values. Extracellular proteolytic enzymes may be involved in the pathogenecity of Trichoderma strains as facultative human pathogens.

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Pheromones have been detected in all fungal phylogenetic lineages. This came as a surprise, as the general role of pheromones in mate attraction was not envisioned for some fungi. Pheromones and pheromone receptor genes have been identified, however, in members of all true fungal lineages, and even for mycelia forming organisms of plant and amoeba lineages, like oomycetes and myxomycetes. The mating systems and genes governing the mating type are different in fungi, ranging from bipolar with two opposite mating types to tetrapolar mating systems (with four possible mating outcomes, only one of which leads to fertile sexual development) in homobasidioymcetes with more than 23,000 mating types occurring in nature. Pheromones and receptors specifically recognizing these pheromones have evolved with slightly different functions in these different systems. This review is dedicated to follow the evolution of pheromone/receptor systems from simple, biallelic bipolar systems to multiallelic, tetrapolar versions and to explain the slightly different functions the pheromone recognition and subsequent signal transduction cascades within the fungal kingdom. The biotechnological implications of a detailed understanding of mating systems for biological control and plant protection, in medicine, and in mushroom breeding are discussed.

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-Salam, A. H. and Abdel-Baky, N. F. (2010): Efficiency of certain parasitoids as bio-agents against some scale insects. Biological control of some scale insects using insect parasitoids. Ph D Thesis printed by VDM Publishing House, Berlin, 189 p

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flétrissement du pois chiche . Thèse de doctorat en Sciences Agronomiques . Institut National Agronomique . El Harrach, Alger , 153 p. Boureghda , H. and Bouznad , Z. ( 2009 ): Biological control of Fusarium wilt of chickpea using isolate of

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diets for arthropods . US Patent 6506597. Collier , T. and van Steenwyk , R. ( 2004 ): A critical evaluation of augmentative biological control . Bio. Cont. 31 , 245 – 256 . De Clercq , P. ( 2004 ): Culture of natural enemies on

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McMurtry, J. A. (1977): Biological control of citrus mites. Proc. Int. soc. Citric. 456–459. Biological control of citrus mites 456 459

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McMurtry, J. A. and Croft, B. A. (1997): Life-styles of phytoseiid mites and their roles in biological control. Annu. Rev. Entomol 42, 291–312. Croft B. A. Life-styles of phytoseiid mites

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