Botany

Permanent URI for this collectionhttp://repository.kln.ac.lk/handle/123456789/3747

Browse

Subject: search.filters.subject.crown rot

Search Results

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Evaluation of antifungal effect of Croton aromaticus on storage life extension of banana
    (2016) Dilhani, S.; Wimalasiri, S.; Abeywickrama, K.; Kannangara, S.
    Effect of Croton aromaticus aqueous, hot water and ethanolic leaf extracts alone and in combination with alum against banana crown rot causing fungal pathogens were investigated using 96 well plate bioassay and liquid bioassay in vitro. According to the results of 96 well plate assay, C. aromaticus aqueous extract successfully inhibited conidial germination of C. musae up to 96.9%. Percentage germination inhibition of F. proliferatum is less than that of C. musae. Hot water extract expressed higher conidial germination inhibition of F. proliferatum. Conidial germination of C. musae was 100% inhibited at the concentration of 600 (%w/v) of ethanoic extract and at the same concentration F. proliferatum was inhibited by 90.4 %. Alum was fungicidal against C. musae and L. theobromae. C. aromaticus leaf extract in combination with alum controlled F. proliferatum more effectively compared to leaf extract alone. During liquid bioassay, ethanolic leaf extract totally inhibited the mycelial growth of test pathogens at the concentration of 800 (%w/v). Among three tested extracts, ethanolic extract was most effective in inhibiting both spore germination and mycelial growth of crown rot causing fungal pathogens.
  • No Thumbnail Available
    Item
    Cymbopogon citratus (lemongrass) and citral a+ b spray treatments alone or in combination with sodium bicarbonate in controlling crown rot in Embul banana (Musa acuminata AAB)
    (2004) Abeywickrama, K.P.; Kularathna, L.; Sarananda, K.; Abeygunawardena, D.
    The mounting pressure against synthetic fungicidal dips and sprays, restrict their use in controlling crown rot, a major post-harvest disease in banana. Generally regarded as safe (GRAS) compounds have a great potential to be used as alternatives to fungicides. Identification of chemical constituents of Cymbopogon citratus oil revealed the presence of citral as the main component. Cymbopogon citratus and citral with sodium bicarbonate (SBC) was fungicidal against the 3 banana fungal pathogens at 0.10-0.20 % v/v and 0.07-0.08 % v/v respectively. Embul banana sprayed with C. citratus alone or in combination with SBC after induced ripening, indicated a crown rot severity of 25 - 5 0% whereas, citral treatment resulted in a slightly lower disease severity. The physico-chemical parameters tested were not affected by the treatments. Oil/citral, SBC treated bananas and control were ranked good to excellent with respect to odour, flavour, taste and overall acceptability. The low disease severity of crown rot due to spray treatment of citral and SBC highlights the importance in adapting this simple, alternate treatment strategy for quality maintenance.
  • Thumbnail Image
    Item
    In vitro application of selected essential oils and their major components in controlling fungal pathogens of crown rot in Embul banana (Musa acuminata – AAB)
    (International Journal of Food Science and Technology, 2008) Herath, H.; Abeywickrama, K.P.
    The necessity for pesticide-free fresh produce have prompted investigating the effect of selected essential oils and their major components on inhibition of conidial germination, appressoria formation and membrane permeability changes of the pathogens responsible for crown rot of banana. Eugenol, which is the major component of the essential oil of Ocimum basilicum, was the most effective chemical component in inhibiting conidial germination of Colletotrichum musae and Fusarium proliferatum in vitro while Cymbopogon citratus oil was the least effective. Both O. basilicum and C. citratus oils and their major components (Eugenol, citral a + b) inhibited appressoria formation by C. musae and changed the selective permeability of conidial membranes. Ocimum basilicum oil, eugenol and citral a + b could be satisfactorily used for inhibition of conidial germination and disruption of conidial activity of banana pathogens