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The fungicide Kitazin and the mycoflora of rice

ABSTRACT The effect of foliar spray of Kitazin (0, 0-Diethyl-S-benzyl thiophosphate) on the rhizosphere, rhizoplane and phyllosphere
mycofloras of rice (Oryza sativa L.) var. Co. 18 was studied. There was significant lowering of the number of fungal propagules per gram of dry soil in the
rhizosphere following spray. Where soil was not covered while spraying, there was greater reduction in the number of fungal
propagules in the rhizosphere than in the covered plots. Between three dilutions of the fungicide used, however, there was
no significant difference in the effect on the mycoflora. In the rhizoplane lesser number of species were isolated from the
sprayed plants as compared to controls. In the phyllosphere, where there was direct contact of the chemical, there was much
more inhibition of fungi. However, comparing the total number of fungal species in the rhizosphere, rhizoplane and phyllosphere,
there is dimunition in number with increasing concentration of the chemical in the rhizoplane and phyllosphere but this is
not so in the rhizosphere. From the data presented, the fungicide appears to be toxic to many saprophytic fungi in the rhizosphere,
rhizoplane and phyllosphere of rice under tropical field conditions.

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    International Journal of Pest Management - INT J PEST MANAGE. 01/1972; 18(1):1-33.