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Onion is widely cultivated crop and attacked by different fungi. Purple blotch of onion caused by Alternaria porri is a continuous threat to Pakistan agriculture industry for the last few years. Generally, fungicides give satisfactory control but due to the environmental concerns, their use should be restricted. In integrated disease management program, cost effective and eco-friendly approach is used to cope with plant pathogens. Therefore, the present study was planned to evaluate the antifungal efficacy of different plants extracts such as Pongamia pinnata, Polyalthia longifolia, Cassia fistula, and Citrus sinensis against A. porri alone as well as synergistically with different concentrations of Mancozeb under in vitro conditions. Methanolic leaves extracts of these plants were mixed with different concentrations (25, 50, and 75%) of fungicide and screened via poisoned food technique to measure percent inhibition of fungal growth. The results indicated that plant extracts alone gave appreciable amount of fungal reduction but when used in combination with fungicide, performed best. Among them P. longifolia gave 73%inhibition, C. sinensis 49%, P. pinnata 70%and Cassia fistula showed46% inhibition respectively. In combination with fungicide, 25% of recommended dose, P. longifolia gave 82.93%, P. pinnata gave 77.07 %, C. sinensis 73.17% and C. fistula gave 62.92% inhibition as compared to control against A. porri. With the increase of fungicide in combination, more reduction in the fungal growth was observed. It is concluded that extracts can be used synergistically with fungicides. The combinations will protect the environment by reducing the amount of fungicide

Cotton is grown all over the world including Asian countries. Severe foliar disease symptoms were observed on cotton in fields from different districts of cotton zone of the province of Punjab, Pakistan. Infected plant leaves were sampled from various areas and processed for the isolation of the causal organism. Fungal isolates were identified morphologically. The conidia of the fungus were observed oblong to ellipsoid, hyaline, and aseptate, but occasionally 1-septate with dimensions ranging from 2.7 to 7.8 × 1.6 to 3.5 μm. A total of two isolates were characterized further for genetic diversity. Both the isolates showed moderate reactions to the NaOH test for E metabolite. The pathogen was morphologically identified as Boeremia exigua. Further, the internal transcribed spacer region (ITS) and TUB gene of the fungal isolates were amplified and analyzed. The sequence of partial ITS and TUB showed 99% homology with the isolates of B. exigua. The pathogenicity test was performed on three months old cotton plants by using two isolates of B. exigua. After 15 days of inoculation, necrotic spots started developing on the leaves that were very similar to those observed in the field. The fungal pathogen was re-isolated from the leaves of all the inoculated plants, identified morphologically following Koch's postulates. This disease might be a potential threat to cotton production in Pakistan in the future. However, further studies are required to know the virulence, behavior, alternate hosts, and spreading nature of the pathogen.

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