الفهرس | Only 14 pages are availabe for public view |
Abstract The aim of the present study was undertaken to control the common seed-borne fungi of faba bean by using safe biological control agents such as antioxidants. Seed health teat were applied on eighteen seed samples of Vicia faba plant at different sites in Dakahlia Governorate were collected from commercial markets, and a total number of 28 fungal species belonging to 17 genera were observed and identified. Pathogenicity test revealed that the most pathogenic isolates on pre-, post-emergence and stunted seedlings were Fusarium oxysporum, Fusarium semitectum and Fusarium moniliforme. Also, it was shown that the most effective antioxidant or formulations of antioxidant for the inhibition of linear growth of the selected fungi was GAWDA and salicylic acid. Concerning the growth and physiological criteria, the obtained results showed that infection with Fusarium sp caused noticeable reduction in root and shoot growth. Moreover, infection induced marked decrease in pigments content, total soluble sugars and total protein. On the other hand the treatment with the antioxidants increase root and shoot vigor, pigments content, T.S.S and total protein. Fusarium sp infection caused noticeable increase in the activity of defense enzymes (i.e, POD, PPO and PAL) and phenol content in infected faba bean plants. In the majority of cases, the applied antioxidants compounds induced significant increase in such enzymes. Fusarium sp infection caused marked decreases in the yield and its components of faba bean plants. On the other hand, seed presoaking in the studied antioxidants improve the yield components.Vicia faba chromosomal aberration test was applied on the studied antioxidants for two different exposure time and mitotic index, phase index, total abnormalities were counted and recorded. Chromosomal aberrations were characterized and classified .SDS- PAGE of M2 seed storage protein revealed a total number of recorded bands was 13 with molecular weights ranging between 15.6 and 133.24 KDa. Such bands are not always expressed in all samples. Six bands were common to all different M2 seeds whose parents were exposed to different treatments of antioxidants. Also, the changes include the appearance and disappearance of bands. The highest percentage of polymorphic bands is 40%, it appears in three samples combination 2, combination 3 and salicylic acid. While the polymorphism in GAWDA is being 0%. Keywords: Vicia faba - Biological control – antioxidants - Fusarium sp – Genotoxicity - chromosome aberration- protein banding pattern. |