Author
|
Submitted to: Proceedings of Southern Weed Science Society
Publication Type: Proceedings Publication Acceptance Date: 1/18/2008 Publication Date: 1/28/2008 Citation: Johnson, W.C. 2008. Cultural control of yellow nutedge (Cyperus esculentus) in transplanted cantaloupe by varying application and timing and type of thin-film mulches. Proceedings of the Southern Weed Science Society Meeting, January 28-30, 2008, Jacksonville, Florida. 61:135. Interpretive Summary: Technical Abstract: Perennial nutsedges are among the most common and troublesome weeds of cucurbit crops in the southeastern U. S. Both species reduce yield of cucurbit crops and are costly to control. Many cantaloupe and watermelon growers in the southeastern U. S. use a system of hybrid transplants on narrow (40 cm wide) thin-film mulch covered seedbeds, overhead irrigation, and use the seedbeds for only one crop in the growing season. The major objective of weed control in this modified system is to simply prevent yield loss from weeds, with little concern in maintaining the integrity of the thin-film mulch. Cucurbits are aggressive crops that offer the potential to be effective competitors with shade-sensitive perennial nutsedges. Furthermore, transplanting crops creates an artificial size differential that beneficially alters the competitive relationship between crops and weeds. The aggressive growth habit of transplanted cucurbits could be capitalized to suppress emergence of perennial nutsedges through the thin-film mulch. Irrigated field trials were conducted from 2004 to 2006 at the Coastal Plain Experiment Station Ponder Farm near Tifton, GA. These sites had heavy natural infestation of yellow nutsedge (<75 plants/m2). Treatments evaluated included all possible combinations of four thin-film mulch application times (3-wk pre-transplant, 2-wk pre-transplant, 1-wk pre-transplant, and day of transplanting) and four types of thin-film mulching material (clear LDPE, black LDPE, white on black LDPE, and bareground). Neither fumigants nor herbicides for yellow nutsedge control were applied in this study. Yellow nutsedge emergence in transplanted cantaloupe was suppressed by the combined effects of a physical barrier provided by thin-film mulches and competitive size differential provided by using cantaloupe transplants. All of the thin-film mulches applied to freshly prepared seedbeds either the day of transplanting or 1-wk before transplanting effectively suppressed yellow nutsedge, without the need for fumigants or herbicides. Yellow nutsedge suppression in bareground seedbeds freshly prepared within 1-wk of transplanting was nearly as effective as suppression from thin-film mulches. Seedbed preparation and applying thin-film mulch 2-wk or 3-wk before transplanting did not effectively suppress yellow nutsedge and cantaloupe yields were reduced by weed competition. In production systems that feature seedbeds used for only a single crop and the integrity of the thin-film mulch is not overly important, this system of cultural weed control offers potential without having to use fumigants or herbicides. Compressing the crop production events such that seedbed preparation, mulch application, and transplanting are in rapid sequence will alter the competitive relationship between cucurbit crops and perennial nutsedges. This practice is consistent with the principles of weed management in organic cropping systems and can be easily implemented. |
