It can be managed by IPM

Tea is an evergreen plant. Different types of tea such as black tea, green tea, white tea are available, all produced from the same plant. The difference between them is only in processing procedures and not in varieties.

Several factors

Production of tea is affected by various biotic and abiotic factors. Among them fungal disease blister blight caused by Exobasidium vexans causes enormous yield losses of 40-50 per cent.

This disease can be managed through integrated management practices like:

Cultural practices: Severely infected tender young tea plants should be pruned immediately.

Pruning the branches of the shade trees to allow sunlight to fall on the tea plants. It is ideal to do it at the beginning of the monsoon season and during the tea leaf plucking stage.

Chemical control: Copper fungicides like copper oxychloride (COC) were found to control the disease most effectively. The copper fungicides act as protective chemicals against systemic fungicides such as Hexagonazole, Propiconazole, and Baycor.

Biological control: Foliar application of bio formulations of Pseudomonas fluorescens Pf1 at rate of 0.5 per cent on 7th,14th and 21st day intervals after planting was found to consistently reduce the infestation for two consecutive seasons, mid-June to October.

Agents

Antagonistic agents like Trichoderma harzianum, Gliocladium virens, and Bacillus subtilis were also found to control tea blister blight most effectively.

Growing resistant cultivars is the best another option to control the tea blister blight.

(A. Balamurugan, is in II M.Sc, (Agri) and Dr. M. Muthamilan is Prof and Head, Department of Plant Pathology, Agricultural College and Research Institute (Tamil Nadu Agricultural University),Madurai – 625 104, Tamil Nadu, Mobile: 09786260033, email: abalamurugan555@gmail.com)