흑색 P. E. Film 피복에서 초당옥수수의 생육기간을 표시하는 GDD 모델 개발

A GDD Model for Super Sweet Corn Grown under Black P. E. Film Mulch

GDD models of corn were developed in baresoil, while sweet and super sweet corns are grown underblack polyethylene (P. E.) film mulch in Korea. To developa suitable GDD model under black P. E. film mulch, a supersweet corn hybrid Cambella-90 was planted from 1 Aprilto 30 June in 2003 at he 10-day intervals under black P. E.film mulch and in bare soil. In bare soil the best GDDmodel was GD = [(H +L )/2 - 10 ], where H was daily∑ ℃maximum temperature but is was substituted for 30 -℃℃ ℃and L was daily minimum temperature, but it was sub-stituted for 10 when lower than 10 . The same GDD℃ ℃model could be adapted for corn grown under black P. E.film mulch, but base temperature was substituted for 9 .℃To determine planting date for the scheduled harvests, accu-mulated GDDs were calculated using 30-year average tem-perature data during the growing season. Under black P. E.film mulch planting dates were determined by subtractingGDD of the hybrid, 970 , from accumulated GDD of℃scheduled harvest dates.