養液栽培におけるイチゴ‘麗紅’の養水分吸収に及ぼす根温の影響

Abstract

This experiment was undertaken to find the effects of root temperature on apparent absorption of water and uptake of nutrients of ‘Reiko’ strawberry plants grown hydroponically. The roots were exposed to 8°, 13°, 18°, and 23°C.1. The rate of water absorption was apparently hastened by higher root temperature at the beginning of treatment and subsequently decreased.2. Higher nutrient uptake resulted at the beginning of the experiment by exposing roots to higher temperature. Nutrient uptake by strawberry roots exposed to 8°C gradually increased over 5 days, whereas it decreased in those exposed to 18° or 23°C.3. After 11 days, the most rapid nutrient uptake by roots was recorded at 18°C. The uptake of P, Ca, Mg, NO3-N, and K was suppressed in that order at lower root temperature; that of NO3-N, Mg, Ca, K, and P was suppressed in that order at higher root temperature 11 to 31 days after experiment was started.4. The highest inorganic nutrient accumulation by whole plants was recorded in plants whose roots were exposed to 18°C. The Ca, P, K, and Mg content per plant decreased with decreasing root temperature. The significant decreases in N and Mg contents were observed in plants whose roots were in nutrient solutions kept at 23°C rather than those roots bathed at 18°C.