Antifungal Activity of Securinine against Some Plant Pathogenic Fungi

The alkaloid securinine was assessed against spore germination of some plant pathogenic and saprophytic fungi (Alternaria alternata, Alternaria brassicae, Alternaria brassicicola, Curvularia lunata, Curvularia maculans, Curvularia pallenscens, Colletotrichum musae, Colletotrichum sp., Erysiphe pisi, Helminthosporium echinoclova, Helminthosporium spiciferum, Heterosporium sp.). Spore germinations of all the tested fungi were inhibited. Alternaria brassicicola, C. lunata, C. pallenscens and H. spiciferum were highly sensitive as complete inhibition of spore germination was observed at very low concentrations (200 ppm).

Antifungal Activity of Narceine Methyl Ester and Narceine Isolated from Corydalis longipes Against Some Phytopathogenic Fungi

Narceine methyl ester and narceine are potent alkaloids which were isolated from Corydalis longipes were found effective in vitro at very low concentration, i.e., 100~500 ppm against spore germination of some test plant pathogenic fungi (Alternaria solani, A. tagetica, Cercospora abelmoschi, Curvularia maculans, Erysiphe cichoracearum, E. pisi, Fusarium udum, Helminthosporium oryzae, H. penniseti, Ustilago cynodontis). Among the test, phytopathogens the spores of F. udum, C. maculans and H. penniseti were highly sensitive at 200 ppm. However, spores of E. pisi, A. solani and A. tagetica were less sensitive at low concentration followed by other test fungi. Most of the fungi showed zero or nearly zero percent spore germination at 400 and 500 ppm.

Effect of the Mixture of Two Plant Alkaloids Isolated from Corydalis longipes Against Balsam Powdery Mildew on Detached Leaves and Pea Powdery Mildew in Field

N-Methylhydrasteine hydroxylactam and 1-methoxyberberine chloride, both alkaloids, extracted from Corydalis longipes have been assayed for their activities against two powdery mildews. The spore germination of Erysiphe cichoracearum on detached leaf of balsam(Impatiens balsaminia) following pre- and post-inoculation treatments by their mixture has shown high efficacy against the pathogen at 100, 200 and 300 microg/ml. The mixture was also effective at both pre- and post-inoculation treatments at 500, 1000, 1500 microg/ml doses against E. pisi causing pea powdery mildew in pea(Pisum sativum) under field conditions. The significant efficacy of the mixture of two compounds against spore germination on detached leaves of balsam and also under field conditions in pea warrants its inclusion in trials against some other diseases under field conditions.