Muscadine Grape Response to Drip Irrigation Rate.

During 1997 through 1999 mature 'Southland' muscadine grapes were grown in Griffin, Ga., with different rates of daily irrigation. Irrigation rates were 0, 15, 22.5, and 30 L·d-1, supplied to individual plants through two emitters. Substantial water deficit occurred during August 1997, May and June 1998, and July and August 1999. The greatest yield response to irrigation was observed during 1998. No significant response to irrigation was observed during 1999, even though soil water was greatly depleted in the upper 30 cm late in the season for control plants. The 3-year average response of total yield indicated a significant response to irrigation, with the greatest yield occurring at the 22.5-L·d-1 rate. Together these data suggest that muscadine grapes respond to irrigation, especially when water deficits during the early to midseason are prevalent. With single trellis vines, 22.5 L·d-1 should provide adequate water in warm, humid regions similar to the southeastern U.S. [ABSTRACT FROM AUTHOR]