Applying Benlate or Rizolex-T (3 g/kg seeds) gave the best results (90.0-96.7% survived seedlings; 3.3-6.7% rotted plants and 93.3% and 83.3% healthy mature plants). While, Rizolex-T and Vitavax-T used at rate of 2 Kg/feddan as soil treatments had no significant effect on disease incidence at seedling stage and produced the lowest significant effect at maturity stage (46.7% and 43.3% healthy mature plants, respectively. Meanwhile, under field conditions all tested seed, soil and seed/soil treatments were significantly effective in reducing charcoal rot disease incidence and increasing sesame seed yield production. However, the combined seed/soil treatments Rizolex-T/Amconil , Rizolex-T/Rizolex-T, Benlate/Vitavax-T and Benlate/Amconil gave the best results in this respect.
Sesame entries responded differently throughout the different stages of disease development under greenhouse conditions. The high susceptible sesame entries (strain 806, strain 792, strain 779, strain 799, B11, strain 772, Giza 32, and Toushka 2) produced < 50% healthy mature plants (3.3-40.0%) meanwhile, the resistant entries (strain 771, Toushka 3, Adnan 1(5/91), and Taka 2) produced 80 to < 90% (80.0-83.3%). The free and total phenols and reducing and total sugars, in general, were obviously higher in the resistant than the susceptible sesame entries. Based on protein bands, the similarity between 15 sesame entries was discussed in light of their disease reactions.
Under field conditions, the sesame entries Aceteru-M, Adnan 1 (5/91), Taka 2, B35 and Mutation 48 were the most resistant while, strain 806 and Giza 32 were the most susceptible. The entries Taka 2, Mutation 48 and Adnan 1 (5/91) produced the highest seed yield while, strain 806, B 11, strain 779, Giza 32, Tushka 1, Aceteru-M and strain 773, Taka 1 were the least in this respect. The seed yield of Tushka 2 "S" was significantly higher than the "R" entries Shandaweel 3 and Aceteru-M. Moreover, Shandaweel 3, Mutation 48 and Giza 32, Taka 3 and Tushka 2 showed the lowest reduction in oil content due to charcoal rot infection (2.53-4.66%) while, the highest reduction was associated with strain 806 (11.27%).
Key words: sesame, charcoal rot, Macrophomina phaseolina, entries, cultivar, fungicides, resistance, protein bands.
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