Mycoflora and Population Dynamics of Some Seedborne Fungi in Relation to the Fungicide Benlate

Abstract

Summary A total of 1478 and 1108 fungal isolates were associated to one gram seeds of Convolvulus arvensis and Rumex dentatus respectively. The dominant genera were Aspergillus and Penicillium followed by Paecilomyces, Rhizopus and Fusarium. Aspergillus niger, A. flavus and A. humicole , were common on both seeds. A. granulosus, Penicillium expansum were restricted to C. arvensis seeds while A. carbonarius and P. lanosum were recovered only from R. dentatus seeds. The dynamic balance of some seedborne fungi fluctuates on soaking of either seeds in the fungicide Benlate, depending on the dose, soaking period and seed sample. The leachable substances which contain sugar, amino acids and phenolics are believed to have antifungicidal effect after prolonged soaking of the seeds in the fungicide. The germination of both seeds stimulated at the lower doses of the fungicide and the stimulation is more pronounced as the soaking period was extended. However, the higher doses were inhibitory to germination of both seeds.