Effects of Root Temperature on Some Physiological and Ecological Characteristics of Strawberry Plants ^|^prime;Reiko^|^prime; Grown in Nutrient Solution

This experiment was undertaken in order to find the effects of root temperature on physiological and ecological characteristics of ′Reiko′ strawberry plants grown in hydroponics. Temperatures were 8, 13 and 18°C in cool season and 13, 18 and 23°C in hot season, respectively.1. Higher root temperatures resulted in more elongation of newly developed roots, leaf blades and petioles in short time, while causing brown colouring of roots, growth depression of newly developed roots, and decreased root dry weight over a long time.2. Higher root temperatures resulted in higher sugar content and rate of respiration in newly developed roots.3. Higher root temperatures resulted in more water absorption by plants and a higher transpiration rate of newly developed leaves, whereas, root temperature showed little effect on water saturation deficit of newly developed leaves.4. Higher root temperatures resulted in less water-vapour diffusion resistance, although chlorophyll content decreased considerably. Net photosynthesis per leaf area of newly developed leaves decreased as root temperature increased; conversely, net photosynthesis per plant was increased.