Seed borne fungi adversely affect the health of seeds and seedlings of Ethopian mustard Brassica carinata by causing seed rot, black, spots and seedlings blight and leaf spot diseases (Kumar, 1997). As a spice the main areas of production are North America. The United Kingdom and Denmark. In India it is cultivated for breeding purposes only. No study has yet performed on these seeds with regard to fungal association.. Therefore, the seed mycoflora of there different cultivars of B. carinata was studied by using blotter paper and agar plate methods. During incubation test, it was found that six fungi viz. Alternaria brassicicola, A. brassicae, A.alternata, Aspergillus flavus, A.niger and Penicillium sp. showed some signs of being pathogenic by showing symptoms on the cotyledonary leaves of the seedlings. Therefore, it was considered desirable to test the pathogenicity of these fungi in plot tests. Seeds of there varieties of B. carinata viz., CM-1, Carinata-234 and Carinata-241 were obtained from Genetic division of IARL New Delhi and were subjected to incubation test by blotter and agar plate methods (Anonymous, 1976). For internal seed mycoflora. seeds were surface sterilized with 0.5% NaOCI for 5 minutes. In this studies, two hundred seeds of each varieties were used by the methods employed. For patho-genicity test, the isolates of these fungi were grown on Richard's medium in 250 ml flasks, except of A. brassicae which was obtained on Potato dextrose agar plate methods (Anonymous, 1976). For internal seed mycoflora, seeds were surface sterilized with 0.5% NaOcl for 5 minutes. In these studies, two hundred seeds of each variety were used by the methods employed. For pathogenicity test, the isolates of these fungi were grown on Richard's mediumin 250 ml flasks, except of A. brassicae which was obtained on Potato dextrose agar (PDA) medium. Freshly harvested fungi of 15 days old cultivars were rolled with the surface sterilized healthy seeds of CM-1. For post test, pre-sterilized seeds rolledwith the fungus were sown in 15 cm diameter clay pots containing autoclaved soil (5 seeds/pot). Pathogenic capabilities of the isolated fungi were first tested on filter rolls half immersed in distilled water in wide mouth tubes (Kumar et al, 1983). Thenin infested soil in pots and by inoculating the foliar parts of the 30 day-old plants of CM-1 with 7 day-old spore cum mycelia suspension. There replications were made for each fungus and the control. Nine fungicides namely Agosan G.N. (3 g/Kg seed). Indofil M-45, Indofil Z-18, Bavistin. Jkstein. Brassicol, Difolatan, Captan and Thirm (each 2g/Kg seed) were evaluated for their efficacy in controlling the seed-borne fungi. The fungitoxicants, were uniformly applied on seed by shaking thoroughly in a conical flasks. The treated and untreated seeds were tested by standard blotter methods after 24 hours of treatment for the control of fungi. Untreated seeds served as control.
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