Six different genera of fungi namely; Alternaria spp., Botrytis cinerea, Fusarium spp., Mucar sp., Penecillium spp. and Sclerotinia sclerotiorum were isolated from different location of Egypt on bean and pea pods. S. sclerotiorum and B. cinerea were most dominant and frequently. All isolated fungi were able to infect pods of snap bean cv. Paulista, while, only B. cinerea and S. sclerotiorum were able to infection of snow snap pea under pathogenicity test.
Under storage conditions, boric and palmitic acids as well as maxgurad, sodium bicarbonate and bafry salts were highly effective on disease reduction when used at 3000 ppm on bean pods that infestation with B. cinerea and S. sclerotiorum also under the natural infestation. Using of atmosphere level contained of 3% O2, 15% CO2 and N 82% was more effective than two levels of atmosphere and caused complete inhibition for growth of B. cinerea and 80.57% growth reduction of S. sclerotiorum on snap bean pods; also it caused protective and improvements the green color of pods by it gave the highest amounts of chlorophyll A, chlorophyll B and A+B compared with the control treatment (Natural air) as well as it increased of phenols contents and decreased of sugars contents. Sprayed of calcium sulphate and potassium salphate (as pre harvest) were more effective on the decreasing of disease caused by B. cinerea and S. sclerotiorum under storage. Meanwhile, salicylic acid was more effective in this respect. Potassium sulphate was the only effective and increase of chlorophyll a, b and a+b when used at 3000 ppm compared with other salts and acids and control treatment. Also their improving of phenols and sugars contents in pods of bean.
On the other side, B. cinerea was more active for production of PG than S. sclerotiorum. Also, it found positive correlation between the enzymes product and the culture age and the reaction time of the two pathogenic fungi. B. cinera was less active for production of CX than S. sclerotiorum after 30 minutes from the 15 days incubation under in vitro and in vivo. The PME enzyme was starting, in bean pods that infected by B. cinerea, S. sclerotiorum or under the natural infection, after 15 days also the % reduction in viscosity was increased according the longed of time reaction from 15 to 30 min.
Key words: bean, B. cinerea, S. sclerotiorum, storage, biochemical, enzymes, salts, acids, atmosphere.
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