PRODUCTION OF BIPOLARIS EUPHORBIAE IN SOLID AND LIQUID CULTURE MEDIA OBTAINED FROM GRAINS AND AGRICULTURAL INDUSTRY RESIDUES

摘要

The introduction of Bipolaris euphorbiae as a bioagent for Euphorbia heterophylla control depends on fungal conidia production in large amount. This work evaluate to solid and liquid culture media obtained from grains and residues from agriculture industries for conidial production of B. euphorbiae. The fungus was Cultivated in different solid media obtained from grains of rice, wheat and sorghun, cracked rice, corn and wheat, ground sorghun, rice, wheat and soybean brans, cassava and soybean peels, cassava peel + soybean bran, sugar-cane bagasse and sugar-cane bagasse + soluble starch. The liquid media were obtained from grains of rice, sorghum and wheat, cracked corn, wheat, soybean and rice bran, cassava and soybean peels, sugar-cane vinasse and water from cassava bran production. The production and viability of conidia and virulence of the fungus were evaluated, and in liquid media assay the micelial biomass was also mesuared. The conidial production is influenced by the type Of Culture medium and was higher on solid media. The larger productions were obtained using sorghum grains and soybean peel as substrates (474 x 10(6) conidia g(-1) and 472 X 10(6) conidia g(-1), respectively). Among the liquid media, the larger conidial production was verified using wheat bran as substrate (1.33 x 10(6) conidia ml(-1)). The fungal virulence and viability of B. euphorbiae is not affected by the preparation of solid or liquid media and by the composition of the culture medium. The conidial viability obtained from most solid and liquid media was greater that 98%. Only conidia produced in the solid media obtained from cracked rice, cassava + soybean peels and soybean bran showed significantly lower viability.