| Popis: |
Inducer resistance chemicals (IRCs) Bion (BTH), chitosan and salicylic acid, bacterial bioagents, i.e. Bacillus chitinosporus, B. megaterium, B. pumilus, B. subtilis, B. thuringiensis, Pseudomonas fluorescens and P. putida and compost tea caused a reduction to the linear growth of the fungus Verticillium dahliae, in culture plates. In general, P. fluorescens followed by B. subtilis were the most efficient in reducing the linear growth of V. dahliae. The viability of microsclerotia of V. dahliae was greatly reduced by the tested bacterial bioagents. In addition, B. megaterium, B. subtilis, P. fluorescens and P. putida were the most efficient bioagents, where no microsclerotia germinated three weeks after treatment with these bioagents. In addition, few of microsclerotia germinated when treated with B. chitinosporus, B. pumilus and B. thuringiensis. However, all the microsclerotia of the control treatment were viable even three weeks after treatment with bioagents. The combination and use singly of BTH, B. subtilis, P. fluorescens and compost resulted in a reduction of verticillium wilt in pepper and increase of fruit, photosynthetic pigments, and vitamin-C compared with the control treatment (infested with the causal fungus). Compost was the most efficient of single tactics in disease management. Moreover, no apparent infection was detected when BTH, the two bioagents B. subtilis and P. fluorescens and compost were used together and the fruit yield, photosynthesis pigments and vitamin-C were, similar to the control treatment (un-infested soil). Photosynthesis pigments including chlorophyll a, chlorophyll b and carotenoids as well as free and total ascorbic acid (vitamin-C) were greatly increased due to the tested treatments, i.e. BTH, both bioagents and compost in pepper plants grown in infested soil compared with those of untreated plants (grown in infested soil only). Compost was the best single treatment for minimizing the reduction in photosynthesis pigments in plants grown in infested soil with V. dahliae, as well as free and total ascorbic acid compared with plants grown in soil infested with the causal fungus without any another treatment. |
