INCREASED YIELD OF HEAT-TOLERANT TOMATOES WITH DEEP TRANSPLANTING, MORNING IRRIGATION, AND WHITE MULCH

Studies mere conducted in Fall 1994 and Summer 1995 to determine growt h and yield response of heat-tolerant tomatoes (Lycopersicon esculentu m Mill.) to transplant depth, time of daily irrigation, and polyethyle ne mulch color. Five-meek-old tomato transplants were planted to a dep th of either 7.5 or 15.0 cm, drip irrigated every other day for 2.5 h starting at either 7:30 AM or 2:30 PM for 80 d following transplanting , and mulched with white-surface (white on black) or black poly ethyle ne. Son temperatures were recorded daily at 4:00 PM for 21 d from the beginning of fruit set (2 weeks following transplanting) until the tom ato canopy shaded the mulch surface. Transplanting tomatoes to a depth of 15.0 cm significantly increased marketable field in both gears and the total yield in 1 gear of this study. Mean fruit mass was not infl uenced by transplant depth, but plant dry mass was significantly incre ased by deeper transplanting in 1995. Morning irrigation increased the marketable and total yields and mean fruit mass in both years and pla nt dry mass in 1995. White-surface mulch had a similar effect on yield and fruit mass. Soil temperature was significantly lower at the 15.0- cm depth than at 7.5 cm in both Sears. Morning irrigation and white-su rface polyethylene mulch also significantly reduced soil temperature i n both years.