TEMPERATURE EFFECT ON SEED-GERMINATION, SEEDLING ROOT DEVELOPMENT AND GROWTH OF SEVERAL VEGETABLES

Experiments were conducted to study the effect of temperature and nutrition on seed germination and plant growth of different plant species. The nutrition studies of vegetables showed a normal response to fertilization rates on deficient soils at temperatures above their critical minimum. At soil temperatures below this litte or no response was obtained to increased P concentration. Plant growth as affected by soil temperature was studied on beans, corn, cucumber, eggplant, pea, pepper, radish, spinach, and watermelon. Growth of peas, radish and spinach was significantly reduced by soil temperatures 10-degrees-C or lower. Corn growth was restricted when soil temperatures were maintained in the range of 12.3-14.5-degrees-C or lower, while growth of bean, cucumber, eggplant, pepper and watermelon was limited when soil temperatures were maintained in the 16.7-18.9-degrees-C temperature range or lower.