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The fungi commonly associated with the spoilage of solanaceous vegetables viz., tomato, brinjal and chilli under storage conditions were studied for a continuous period of one year during 1993.
Tomato fruits were found to be damaged by Aspergillus flavus, Fusarium solani, F. oxysporum, colletotrichum gloeosporioides and Alternaria solani. These fungi were present throughout the year, while Rhizoctonia solani, Mucor hiemalis and Choanephora cucurbitarum were seasonal in occurrence. Mucor hiemalis and C. cucurbitarum recorded in the present study are new reports.
With brinjal the common pathogens inoculated Alternaria solani, Fusarium solani, Colletotrichum gloeosporioides, Penicillium sp. Botrytis cinerea, Rhizopus nigricans, Curvularia lunata and Botryodiplodia theobromae. While Phomopsis vexans, Phytophthora palmivora, Pythium aphanidermatum and Rhizoctonia solani were confined to the rainy periods of the year.

Rhizopus. Nigricans and P. palmivora recorded in the present study are new reports on brinjal.
Studies with chilli yielded fungi like Fusarium solani, F. oxysporum and Colletotrichum capsici throughout the year. Phutophtnora capsici and Mucor hiemalis were recorded during the rainy seasons only.
Mucor hiemalies and Penicillium italicum recorded in the present study are new reports in chilli.
The nature and extent of damage caused by major pathogens were studied for all the three crops. Based on the frequency of occurrence and extent of damage two pathogens were selected for each crop for further in vitro studies. This included F. solani and R. solani for tomato and F. solani and A. solani and A. solani for brinjal. For chilli, the pathogens selected included F. solani and C. capsici.
Studies on the occurrence of fungal pathogens and their correlation with weather parameters have showed minimum spoilage during the dry periods of the year viz., January, February and March. A drift in the fungal flora was notices with changing seasons. Low temperature coupled with high relative humidity and rainfall were found to be favourable for growth and sporulation of fungi. Fungi like Phytophthora, Pythium, Rhizoctonia and Mucor were found to occur during this period.

The phylloplane fungi associated with tomato, brinjal and chilli were studied. The plants were raised in pots and observations were recorded at fortnightly intervals for a continuous period of four months. Brinjal leaves harboured the maximum fungal population followed by tomato and chilli. The fungi included the common pathogens and saprophytes. Fungi like Botryodiplodia theobromae, Pestalotia palmarum, Phoma sp., Trichoderma viride. A. niger, A. flavus and A. terréus were common to all the three crops and were selected for in vitro studies, along with the common pathogens of the specific crops in search for a suitable antagonist.
Based on the above studies B. theobromae, T. viride and Aspergillus spp. Viz., A. niger, A. flavus and A. terrus were selected as suitable antagonist. But only T. viride was utilised for further studies.
The mechanism of action of Trichoderma viride towards Fusarium solani was through coiling and penetration while with R. solani the inhibition was through coiling and disintegration of hyphase. Penetration and disintegration was found with A. solani while for C. capasici it was by penetration alone.
The role of Trichoderma as a biological antagonist against the common fruit rot pathogens were studied. Fresh samples of tomato, brinjal and chilli were collected and sprayed with the conidial suspension of T. viride, airdried and inoculated with their respective pathogens and the extent of damage recorded and compared with the control. It was observed that T. viride was effective in reducing the fruit rot of tomato caused by the major pathogens viz., F. solani and R. solani by 52 and 50 percent respectively up to 12 days of storage under artificial inoculated conditions at room temperature. Similar results were also obtained with F. solani in brinjal (48 percent) and C. capsici in chilli (43 percent).
The study thus highlighted the effectiveness of utilising Trichoderma as a biological antagonist against the major storage pathogens of tomato, brinjal and chilli.