During systematic survey of parasitic fungi at Faizabad (U.P.), author came across a new leaf spot disease of harsingar (Nyctanthes arbor-tristis L.) caused by Mycothecium verrucaria (Alb. & Schw.)Ditam. ex Fr.
The small spherical yellowish leaf spots become visible in the month of September. With time the spots increase in size and finally become greyish followed by light brown and the death of the leaf tissues.
The pathogen was isolated on PDA medium by usual method. Healthy leaves when inoculated artificially by spore suspension, developed spots characteristics in nature after 15 days. Reisolations of the artificially infected spots yielded Myrothecium verrucaria.
The morphological obsrvations were made in culture and in nature. The mycelium is septate, white to olive green and become olivaceous black with ageing. Conidiophore about 70-78 µ long, smooth, erect, septate and brached above penicillately producing conidia borne in chains, directly and on phialids. Conidia elongate, to ovate, smooth, dusky, olive green to olivaceous black and about 6-9.7X1.46-4.0 µ.
On the basis of morphological characters the fungus was identified as Myrothecium verrucaria (Alb. & Schw.) Ditm ex Fr.
Myrothecium verrucaria has earlier been reported from soil and perhaps not as parasite hence this has been described as a causal organism of leaf spot disease of N. arbor-tritis L. earlier not reported from India.
This fungus has been deposited in the Herbarium CMI as IMI. 209313 and Herbarium K.S. Saket P.G. College,Faizabad as RSK-154/S.
Cited this as: Kanaujia R.S. (1977): A new leaf spot disease of Nyctanthes arbor-tristis caused by Myrothecium verrucaria from India. Indian Phytopathology. 30(2): 291-292.
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