Effects of chitosan seed treatment on Colletotrichum sp. and seedling growth of chili cv. 'Jinda'.

摘要

The effects of chitosan on the growth of Colletotrichum sp. that caused anthracnose disease in chilli (Capsicum annuum) were investigated. Chitosan was homogeneously added to potato dextrose agar (PDA) at pH 5.6. The optimum concentration of chitosan to control mycelial growth was 0.8%. In the following experiments, seeds treated with chitosan solution for 60 minutes placed on a wet paper surface inoculated with a spore suspension showed reduced fungal infection. Chitosan treatment, particularly at 0.8%, also increased seedling survival to 77% whereas, without chitosan, ~33%. Similarly, seedling survival of in vivo seeds collected from chilli fruits and inoculated with Colletotrichum sp. increased with chitosan treatments above 0.4%. The lignin content of seedlings obtained from chitosan-treated seeds was higher than that without chitosan treatment. The results demonstrate that chitosan seed treatment could reduce Colletotrichum sp. infection and improve seedling performance..