Ali, M., Osman, E., Ibrahim, T., Khalafalla, G., Amin, G. (2004). IN VITRO ANTAGONISM BETWEEN SOILRHIZOSPHERE MICROORGANISMS AND A. Strictum THE CAUSAL FUNGUS OF ACREMONIUM WILT IN GRAIN SORGHUM.. Journal of Agricultural Chemistry and Biotechnology, 29(10), 5821-5833. doi: 10.21608/jacb.2004.242699
M. A. Ali; Ettimad A. Osman; Thanaa F. Ibrahim; G. Khalafalla; G. Amin. "IN VITRO ANTAGONISM BETWEEN SOILRHIZOSPHERE MICROORGANISMS AND A. Strictum THE CAUSAL FUNGUS OF ACREMONIUM WILT IN GRAIN SORGHUM.". Journal of Agricultural Chemistry and Biotechnology, 29, 10, 2004, 5821-5833. doi: 10.21608/jacb.2004.242699
Ali, M., Osman, E., Ibrahim, T., Khalafalla, G., Amin, G. (2004). 'IN VITRO ANTAGONISM BETWEEN SOILRHIZOSPHERE MICROORGANISMS AND A. Strictum THE CAUSAL FUNGUS OF ACREMONIUM WILT IN GRAIN SORGHUM.', Journal of Agricultural Chemistry and Biotechnology, 29(10), pp. 5821-5833. doi: 10.21608/jacb.2004.242699
Ali, M., Osman, E., Ibrahim, T., Khalafalla, G., Amin, G. IN VITRO ANTAGONISM BETWEEN SOILRHIZOSPHERE MICROORGANISMS AND A. Strictum THE CAUSAL FUNGUS OF ACREMONIUM WILT IN GRAIN SORGHUM.. Journal of Agricultural Chemistry and Biotechnology, 2004; 29(10): 5821-5833. doi: 10.21608/jacb.2004.242699
IN VITRO ANTAGONISM BETWEEN SOILRHIZOSPHERE MICROORGANISMS AND A. Strictum THE CAUSAL FUNGUS OF ACREMONIUM WILT IN GRAIN SORGHUM.
1Agricultural Microbiology Dept., Fac. of Agric.,Cairo Univ.,Giza.
2Maize, Sugar and Foliage Crops Dis. Res. Dept.,Plant Pathol. Res. Inst., Agric. Res. Center, Giza.
Abstract
Population densities of bacteria, sporeformers, actinomycetes and fungi were enumerated in soil and rhizosphere samples collected from fields cultivated either with a susceptible(Giza-113) or a resistant (Dorado) grain sorghum cultivars after 15,30,45, and 90 days of sward establishment. Results revealed that the rhizosphere of both cultivars harboured higher counts of the examined microorganisms than those found in soil apart .Counts of total bacteria, spore-formers and fungi increased as the plant growth increased till the45-day period and gradually decreased thereafter. Bacteria were the highest followed by actinomycetes, fungi and sporeformers being 34.2, 8.1, 0.6 and 0.3 x 106 cfu/g soil,respectively. During the earlier plant growth periods, counts of each type of microorganisms increased in the rhizosphere of both cultivars being higher with resistant plants.Out of 367 isolates (291 bacteria, 51 actinomycetes and 25 fungi) isolated from soil and the rhizosphere of Dorado and Giza 113 plants, 183 isolates (151 bacteria and 32 actinomycetes) proved to be effective against A. strictum. Twenty isolates of bacteria (identified as Bacillus spp.) and 9 isolates of actinomycetes (identified as Streptomyces spp.) showed the highest antagonistic effect. Isolate No. (9) of Bacillus spp. (identified as B. subti/is) and Streptomyces spp. No. (3) were the most antagonistic isolates. Culture filtrates of both bioagents individually singly or in combination (1: 1) inhibited the mycelial growth of A. strictum