EFFECT OF FUNGICIDES ON COCHLIOBOLUS SATIVUS AND OTHER FUNGI ON BARLEY SEED IN SOIL

Abstract

Nineteen seed-treatment fungicides were tested for their effects on the microflora of barley seed. The barley seed, naturally infested with Cochliobolus sativus, Alternaria alternata and Streptomyces species, was treated, placed m soil for seven days at 20 °C, and then examined. The wide-spectrum fungicides Ceresan M, Panogen PX and Dithane M 45 provided the best control of C. sativus; the more selective fungicides provided little or no control. Alternaria alternata was controlled (P < 0.05) by all fungicides except SWF 850 and G 696. In contrast, growth of Streptomyces spp. was enhanced by Chemagro 4497, G 696, SWF 860, SWF 800, F 735 and SWF 850; the other chemicals had no effect. Because of general agreement between soil and filter paper techniques and the amount of work involved in the former, the filter paper technique is recommended for initial screening of fungicides.