THE EFFECT OF ROOT ZONE TEMPERATURE ON NUTRIENT-UPTAKE OF TOMATO

Tomato (Lvcopersicon esculentum cv. Burpee Big Boy Hybrid) was grown in a growth chamber under six root zone temperature treatments: 10, 15.6, 21.1, 26.7, 32.2, and 37.8 °C. with four replications per treatment. Ambient air temperature was 21.1 'C. The experiment was repeated three times and the treatments were completely randomized. All treatments received the same nutrient concentrations. Nutrient uptake for each element generally peaked at 26.7 °C. Uptake of all mineral elements was significantly different with each temperature treatment except for B, Fe, and Mo which did not respond to temperature. Root and shoot dry weight, rate of shoot growth, plant height, and water use also peaked at 25 °C. Optimal temperature appears to be approximately 25 °c for uptake of the majority of mineral elements and all plant growth responses measured. © 1990, Taylor & Francis Group, LLC. All rights reserved.