Qualidade sanitária e fisiológica de sementes de feijão-caupi (Vigna unguiculata L.Walp)

Abstract

Sanity and physiological quality of seeds interfere directly in success of crop. In this work, to study the incidence of fungi associated at cowpea seeds of germoplasm bane from Embrapa Meio Norte. To detect fungi utilized blotter test method, to evaluate bactérias utilized the plating in semi selective culture and the germination and vigora test was according to Regra para Análises de Sementes. Was utilized 4 replications with 50 seeds for all the tests and the analyses realized in Microbiology Laboratory in Universidade Estadual do Maranhão. Were identified two contaminates genera of fungi, observing in all genotypes the Aspergillus genera and in small frequency Penicillium genera. Phytopathogenics fungi was detected too like Fusarium sp, Colletotrichum sp e Macrophomina phaseolina that are common fungi in cowpea seeds. The genotype BR 17 Gurgéia show 39 % and MNC — 99-5056-11 20 % of Fusarium sp. The genera Colletotrichum, was verified in some genotypes like MNC-99-5106-16 (10,5 %), TE 97-3096-18 (12 %), TE 97-304-4 (9,5 %), and in the others the index was 0 a 6 %. Macrophomia phaseolina is one of fungi more importante to cowpea crop, because causes deseases like podridão cinzenta do caule. Verifyed the presence of this, in genotypes like: MNC - 99-5056-11 (7 %), MNC-99-5086 -8 (12 %) e BR 17 Gurguéia (4 %). Was identified only bactérias of genera Xanthomonas, with small incidence, in seed from Maranhão State. In respect the physiological analisys, in Maranhão seeds, observe the better values of germination and vigora. In that of germoplasm bane from Embrapa, had small values, some that with zero vigora.