Efficacy of certain fungicide treatments for the control of seedborne diseases of soybean

The results found no significant increase in seed germination and no difference in percentage of basal stem rot disease caused by Sclerotium rolfsii among treatments. Seed treatment alone could not control seedborn pathogen. Seed treatment followed by 1-2 applications of sprayed fungicide in the dry season gave satisfactory results. However, seed treatment followed by 3 applications of tested fungicide gave highest percentage of healthy normal seed and less percentage of infected seed. No significant increase in seed yield and no seed discoloration were found in dry season. In wet season, the results also found no significant increase in seed germination and no difference in percentage of basal stem rot disease caused by Sclerotium rolfsii among treatments. Seed treatment alone could not control seedborne pathogens. Three applications of myclobutanil without seed treatment gave very effective control of soybean rust, anthracnose and bacterial pustule in the wet season. Seed treatment followed by 2 applications of sprayed fungicide in the wet season gave satisfactory results. However, seed treatment followed by 3 applications of tested fungicid gave highest percentage of healthy normal seed and less percentage of infected seed. In the wet season applications of myclobutanil alone gave the highest yield but this was not significantly different from treated seed plus 2 or 3 applications of tested fungicide. The percentage of purple seed found between 2.75-6.50 percent. Fungi found to be associated with soybean seed grown during the dry season included: Penicillium sp., Aspergillus flavus, Diaporthe phaseolorum, Aspergillus niger, Macrophomina phasealina, Fusarium sp. and Curvularia sp. Seed grown during the wet season: Phoma sp., Cercospora sojina, Aspergillus niger, Diaporthe phaseolorum and Cercospora kikuchii were found in association with the harvested seed