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Sclerotium rolfsii Sacc. is known to be a serious pathogen on many crops of economic importance including cucurbits. Due to proliferic growth and ability to forming sclerotia, this pathogen is the major constraint in successful cultivation of cucumber. The present investigation was thus carried out to evaluate the potential of nine different fungicides i.e. carbendazim, thiophenate methyl, vinclozoline, captan, copper oxychloride, mancozeb, hexaconazole, mycobutanil and propiconazole at different concentrations of 10, 50, 100 and 150 ppm, on the growth inhibition of S. rolfsii. The primary assessment was made on in vitro screening of fungicides and its concentration whereby hexaconazole at lowest concentration (10 ppm) rendered the most vital effect (P<0.0001) on growth reduction ability followed by propiconazole and mycobutanil. No growth of S. rolfsii observed on plates amended with hexaconazole when the concentration was further increased. Similar effect was traced in an experiment conducted on root trainer. The percent infected plant also provided the same impact of fungicides received in toxic-assay experiment. Maximum seedlings protection of cucumber was achieved through seed application of hexaconazole even at lowest concentration (P<0.01); similarly, no mortality was detected on higher concentration of this fungicide. Although our result directly claiming the best effect of hexaconazole but we propose to use a combination of fungicides from different groups in order to avoid resistance development in S. rolfsii against a particular fungicide. A combination of carbendazim and hexaconazole is hereby proposed for seedling protection of cucumber to S. rolfsii.How to view point the article : Kumar, Ritesh, Ghatak, Abhijeet and Bhagat, Arun P. (2018). Assessing fungicides for seedling protection of cucumber to collar rot disease caused by Sclerotium rolfsii. Internat. J. Plant Protec., 11(1) : 10-17,

Geminiviruses infect many crop plants, and are limiting factors for vegetable crop production. Begomoviruses (Geminiviridae) cause typical symptoms of leaf curling and puckering in nightshade (Solanum nigrum), a seasonal weed in Bihar, India. To investigate if nightshade was an intermediate host for begomovirus, virus DNA was extracted and characterized. The DNA-A of the virus yielded 2737 nt and DNA-B yielded 2706 nt. The intergenic region (IR) showed a conserved nonanucleotide sequence that potentially forms a stem-loop structure. The genomic sequence of DNA-A shared 94% identity with that of Tomato leaf curl New Delhi virus (ToLCNDV)-ivy gourd isolate. However, the sequence of DNA-B showed 95% identity with a bitter gourd isolate. PCR-based detection revealed the presence ToLCNDV in bottle gourd, pumpkin, sponge gourd, and bitter gourd. The IR sequences of the viruses isolated from these cucurbits and tomato were 100% identical. Whitefly-mediated transmission of the virus to cucurbits and tomato from nightshade was also demonstrated. These results indicate that nightshade may act as reservoir of ToLCNDV, and is involved in developing epidemics in cucurbit species. The strain of ToLCNDV has probably adapted from solanaceous to cucurbitaceous hosts. This is the first report of ToLCNDV infecting nightshade in India, highlighting this virus as a possible cause of disease epidemics in economically important cucurbits.

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