Abstract:
The present study focuses on the aetiology of leaf spot
disease and its impact on beetroot production in the Jaffna
peninsula. A survey and field study was carried out to under stand present status of the disease. The fungus associated
with the leaf spot lesions was isolated and identified based
on morphological features and sequence analysis. The survey
has shown drawbacks in the cultivation practices, such as
selection of cultivation season, selection of variety and inad equate weed management practices. The initial symptoms
were noted in seedling stage, and the disease incidence and
severity progressed with time. The disease incidence and
severity index were 85% and 2.71 at 48days. The field exper iment has revealed the negative correlation between leaf
spot disease development and yield. The fungal isolates
produced obclavate shape, hyaline, multiseptated conidia
on dark coloured unbranched sparingly septate conidio phores. The isolates showed 99.25% sequence identity with
Cercospora beticola.
