Little leaf of brinjal is one of the most serious diseases of brinjal in the areas of its cultivation. "Brinjal" is a common name in some areas for the plant species Solanum melongena, the eggplant. The disease is known to cause heavy economic losses in India. As the name indicates, symptoms of the disease include shortening of the petioles and production of leaves which are much smaller in size than are normal for the species. Petioles are so short that leaves appear to be glued to the stem. They become soft, glabrous, somewhat yellow. Affected plants do not bear any flowers or fruits if infection is in early stages of plant growth. In cases of late season infections, fruits may remain small, become hard and unfit for consumption or marketing. The disease is caused by a plant pathogenic mollicute, Phytoplasma (earlier known as mycoplasmalike organism or MLO) and is transmitted by the insect vector, Hishimonus phycitis which belongs to the group of leafhoppers.
Control Measures
Management of the insect vector by means of insecticides and cultivation of resistant varieties are the principal means of management of the disease.
Other techniques include
burning of infected plants
crop rotation to ensure death of disease-causing pathogen
spraying of varavion at a regular interval of 15 days
Tetracycline antibiotic can also be used to treat the disease.
Sources
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