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Levels of Three Antifungal Proteins During Development, Germination and in Response to Fungal Infection in Grain Sorghum Kumari, R. Sunitha; Chandrashekar, A. & Frekeriksen, R.A. Abstract An enzyme linked immunosorbent assay (ELISA) for the levels of three antifungal proteins (18, 26 and 30 kDa) in sorghum (Sorghum bicolor (L.) Moench) varieties susceptible and resistant to grain moulds was analysed. The results suggested that hard and mould resistant grains have higher levels of the 18 kDa and 30 kDa antifungal proteins. The levels of these proteins were also analysed at 7, 14, 21, 28, 35 and 42 days alter anthesis during seed development using SDS-PAGE and ELISA in a variety that was hard and resistant to fungal infection (E-35-1) and a soft susceptible variety(M-35-I). A 30 kDa antifungal protein increased in amount in developing seeds from 7 days after anthesis up to 28 days and decreased thereafter. Two other antifungal proteins (18 and 26 kDa) appeared in seed sample 14 days after anthesis. The resistant variety contained more of 30 and 18 kDa antifungal proteins at all developmental stages. Levels of the 26 kDa protein increased in the susceptible variety after inoculation of grains with Fusarium moniliforme, suggesting its inducibility. There was little change in the resistant variety in the levels Of all the three antifungal proteins after inoculation. During germination the levels of the three proteins, especially that of the 18 kDa, increased in extractibility. A complex regulatory mechanism controlling the levels of three proteins during development and germination is shown by the present study. Keywords Disease resistance, ELISA, grain moulds, inducibility, kDa protein

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Kumari, R. Sunitha; Chandrashekar, A. & Frekeriksen, R.A. Résumé Un test d'ELISA etait utilise pour determiner les niveaux de trois proteines antichampignons (18. 26 et 30 KDa) sur les varietes du sorgho (Sorghum bicolor (L.) Moench) susceptibles et resistantes au "grain mould". Les resultats ont montre que les grains resistants ont des niveaux eleves (18 KDa et 30 KDa) de proteines antichampignons. Les niveaux de ces proteines etaient aussi analyses a 7 14 21 28 35 et 42 jours apres l'anthese pendant le developpement de la semence moyennant les tests de SDS-PAGE et ELISA sur une variete a grains durs et resistante a l'infection au champignon (E-35-1) et une variete susceptible a grains moux (M-35-1 ). La quantite de proteine antichampignon 30 KDa augmentait dans les semences a partir de 7 jours apres l'anthese jusqu'a 28 jours puis decroissait. Deux autres proteines antichampignons (18 et 26 KDa) apparaissaient 14 jours apres l'anthese dans l'echantillon de semences. La variete resistante contenait plus de proteines antichampignons 10 et 18 KDa a tous les stades de developpement. Des niveaux de proteines de 26 KDa augmentaient sur la variete susceptible apres inoculation de grains avec le Fusarium monoliforme, ce qui prouve son effet par induction. Il y a peu de changement pour une variete resistante aux niveaux de tousles trois proteines antichampignons apres leur inoculation. Durant la germination, les niveaux de trois proteines particulierement le 18 KDa, augmentaient leur extraction. Un mecanisme complexe de regulation controllant les niveaux de trois proteines durant le developpement et la germination est montre dans la presente etude. Mots Clés Resistance a la maladie, ELISA, grain mould, effet d'induction, proteine kDa

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