Transplant Age Has Little Influence on Yield of Muskmelon (Cucumis melo L.)

Abstract

Fig. 1. Mean cumulative yields resulting from 2-, 4-, 6-, and 8-week-old muskmelon transplants and a direct-seeded control (1993 only). Transplants are used extensively in the southeastern United States for vegetable crops, including muskmelon. Transplant age is important because growers often contract to receive transplants at a specific time and the performance of older transplants is uncertain. The relationship between transplant age and yield in several crops is not clear (Kratky et al., 1982; Lamont, 1992; Leskovar et al., 1991; McCraw and Greig, 1986; Weston, 1988; Weston and Zandstra, 1989). Recently, research with squash (Cucurbita pepo L.) (NeSmith, 1993) and watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] (Vavrina et al., 1993) indicated that transplant age had no influence on early and total yields of these cucurbit crops. The objective of this research was to examine the influence of transplant age on muskmelon yield. ‘Cordele’ muskmelon transplants of varying ages were grown in field experiments during 1992 and 1993 at the Georgia Station Horticultural Research Farm in Griffin. Transplants for both years were grown in 50-cm cells containing a commercial growing medium (Metro-Mix 300; W.R. Grace and Co., Cambridge, Mass.). Single seeds were planted in cells at different times so that transplants of designated ages (2, 4, 6, and 8 weeks old) were available for planting in the field on a common date. The transplants were watered daily and fertilized three times weekly with a solution of commercial fertilizer (20N–8.8P–16.6K plus micronutrients at a concentration of 200 ppm N; Peters Professional General Purpose Fertilizer, W.R. Grace and Co.). Minima and maxima in the greenhouse for transplant production were 20 to 21C and 25 to 30C. Only natural light was used, and its transmission into the greenhouse was ≈70% of sunlight. On 4 May 1992 and 27 Apr. 1993, transplants of all ages were hand-planted to a Cecil sandy clay loam (clayey, kaolinitic, Thermic Typic Hapludult) soil. Also included in the 1993 experiment was a direct-seeded treatment for comparison. Rows were 1.5 m apart,