Mechanism of Tea Dormancy : Effect of Temperature on Growth and Dormancy of Tea Plant

Abstract

Tea plants of N. E. India remain dormant during the winter season when the minimum night temperature goes below 120 C for a period of about 3 to 4 months and the day length also drops below 11 hr 15 min. Maintenance of high day (27.50C ± 20C) and night (200C ± 20C) tem¬peratures during the entire winter season from November to March could not prevent dormancy but exposure to high temperature during winter advanced bud break by about a month. Exposure of plants to 50C± 20C day and night temperature during summer stopped growth completely but growth started soon after raising the temperature to 27.50C±20C. Besides low temperature, day length is also involved in the mechanism of dormancy. The role played by high and low temperatures on growth and dormancy of the tea plant is discussed.