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[Display omitted] • Fusarium species is the most destructive storage pathogen of stored potato tubers. • Mixed infection of Fusarium aggravates the dry rot occurrence during storage. • The fungal infection caused a significant reduction in starch and amylose content of the tubers. • Amylopectin, reducing sugars, sucrose and total soluble sugar content were increased after fungal infection. • Overall there was deterioration in quality parameters of potato tuber due to fungal infection. Fusarium is a major spoilage fungus of potato tubers during post-harvest storage. The dry rot disease caused by Fusarium species severely affects the harvested potatoes and impose a critical loss to processing industries and consumers. In our experiment, we investigated the occurrence of Fusarium sambucinum (FS) and Fusarium oxysporum (FO) as major storage fungus causing Fusarium dry rot in potato tubers. Further, we performed morpho-molecular identification of both the fungi and confirmed their pathogenicity on potato tuber during storage. We evaluated the susceptibility parameters and quality attributes during infection in two popular cultivars namely 'Kufri Pukhraj' (table purpose) and 'Kufri Chipsona 3' (processing purpose). Out of two cultivars, 'Kufri Pukhraj' was shown to have greater susceptibility as compared to 'Kufri Chipsona 3' in terms of lesion diameter, fungus penetration and rot volume during periodic observation of 20, 40 and 60 d of storage. FS was highly aggressive as compared to FO. However, a mixed inoculum of Fusarium species caused higher damage irrespective of cultivars. The physicochemical analysis revealed that fungus infection (individual or mixed inoculum) leads to a reduction in starch and amylose content in both the cultivars after 60 d of storage. Moreover, amylopectin, reducing sugars, sucrose and total soluble sugar content were increased in response to fungal infection in both cultivars. Pearson correlation analysis indicated that lesion diameter and rot volume was negatively correlated (R < -0.80) with starch and amylose content. However, amylopectin, reducing sugar, sucrose and total soluble sugar was positively correlated with susceptibility parameters. This study highlights the impact of storage fungus infection on the nutritional quality parameters of potato tubers which is a critical concern for consumers and processing industries. [ABSTRACT FROM AUTHOR]

Abstract: The major objectives of the present work were to express, purify and investigate the antifungal activity of the recombinant rice chitinase in controlling grey mould onset after loquat harvest. Rice class I chitinase gene was inserted into the vector pPIC9 to construct pPIC9/Chi, and then expressed in Pichia pastoris strain GS115. The expression level and antifungal activity of the recombinant chitinase against Botrytis cinerea on loquat were analysed. As a result, the chitinase was successfully expressed at a high level in the host yeasts and was enzymatically active. In addition, the chitinase significantly inhibited the spread of the grey mould on the rot region of loquat. Taken together, the present study demonstrates that the chitinase has antifungal activities against grey mould and may be developed for an effective biocontrol agent for fruit storage. [Copyright &y& Elsevier]