ARS | Publication request: Organic watermelon production systems

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: November 1, 2009
Publication Date: May 1, 2010
Citation: Webber III, C.L., Davis, A.R., Shrefler, J.W. 2010. Organic watermelon production systems [abstract]. In: Proceedings of the Oklahoma Academy of Science. November 6, 2009. Ada, Oklahoma. Vol. 89:95.

Technical Abstract: The increasing perception by consumers that organic food tastes better and is healthier continues to expand the demand for organically produced crops. Research investigating certified organic production requires a systems approach to determine the optimum combination of individual components to maximize crop yields. Research was conducted at two locations on organically certified land to determine the impact of weed control and variety selection on watermelon (Citrullus lanatus var. lanatus L.) yields. Six watermelon varieties were transplanted at two locations (Lane, Ok and Center Point, OK), into randomized complete block designed experiments with four replications. The six varieties included three seeded varieties (‘Early Moonbeam,’ ‘Sugar Baby,’ and ‘Allsweet’) and three seedless varieties (‘Triple Crown,’ ‘Triple Prize,’ and ‘Triple Star’). The weed control system at Lane utilized black plastic mulch on the crop row, while the area between rows was cultivated to control weeds. The no-till organic system at Center Point used a mowed rye and vetch cover crop, hand weeding, and vinegar (5% acetic acid) for weed control. When averaged across watermelon varieties, the organic production system at Lane produced significantly more fruit per plant (4.2 vs. 2.3 fruit/plant), greater marketable yields (35.2 vs. 18.5 lb/plants), and higher average marketable weight per fruit (13.4 vs. 8.9 lb) than at Center Point. Plants at Center Point produced a greater percentage of marketable fruit, 92%, compared to plants at Lane, 63%. When comparison was made between locations, four of six varieties had significantly greater numbers of fruit per plant and higher marketable yields at Lane than at Center Point. Except for ‘Early Moonbeam,’ all other varieties produced significantly heavier fruit at Lane than at Center Point. In contrast, the Center Point location produced a greater percentage of marketable fruit for all varieties except ‘Allsweet.’ The plastic mulch and cultivation between crop rows was a successful method of weed control at the Lane location and provided a stronger weed barrier to prevent than the cover crop mulch at Center Point. Further research will specifically investigate the impact of weed competition on watermelon fruit quality.