Authors : Parul Trivedi Mishra
Page Nos : 193-197
Description :
Cotton (Gossypium L.) is one of the commercial fibre yielding crop of India. It occupies a premier place
in the national economy of our country due to its high-grade fibre rich in vitamins, enzymes and oil
used as medicine and oil yielding cash crop. So the present investigation was done in order to check
the efficacy of fungitoxicants like Agrosan G.N., Aureofungin, Captan etc. on the pathogenic effect of
Alternaria alternata in causing lesion development on cotton leaves. For this, fresh healthy leaves of
same age having no disease symptoms were excised and collected in polythene bags. Fungitoxicants in
dilution 0.05, 0.10, 0.15…… and 0.40 percent were inoculated by spraying with an automizer at the
point of injury made. Afterwards leaves were inoculated by spraying with one drop of 0.001 ml of spore
suspension at four points of leaf lamina and were kept in petridishes in moist chamber over surface
sterilized bent glass rods to avoid direct contact with moist filter paper. All sets were incubated at room
temperature 25 ± 1oC. It was evident from the data that all the fungitoxicants, used in different
concentration were better in performance in comparison to control. Out of the 24 fungicides and an
antibiotic (Aureofungin) tested, Agrosan G.N., Captan, Ceresan and Vitavax etc. proved to be most
effective by not producing any pathogenic effect. Other fungitoxicants viz. Brassicol, Calixin were found
effective in producing light yellow lesions, while extensive brown spots were observed in the treatment
with Bavistin.