파종시기별 유효적산온도(GDD)가 옥수수의 생육 및 수량변화에 미치는 영향

Effects of Growing Degree Days on Growth and Yield of Maize Depending on the Sowing Date

A total of 15 different corn hybrids, Kwangpyeongok, Gangdaok, Yanganok, Singwangok, Jangdaok, Cheonganok, Cheongdaok, Andaok, Dapyeongok, Pyeongkangok, Pyeonganok, Daanok, Sunwon 184, Gangilok, and P3394 was used to investigate the growth and yield depending on the sowing date. The sowing dates were April 5, June 25, and July 5 and each experiments was performed in triplicste. The growth of Gangdaok was the highest. However, although the growth of Kwangpyeongok, was lower thanthar of Gangdaok, its stem height to ear height ratio was lower than that of Gangdaok, thus , Kwangpyeongok may be more suitable for stable cultivation. Both growth and yield of Daanok were low, regardless of planting date, but yield and ear shape of Pyeongkangok and Dapyeongok were for fresh corn. Growth and yield of the 15 different corn hybrids varied depending on the planting date, However, the growth degree days (GDD) was the most important factor governing the maturity of corn. More than 1500°C of GDD was sufficient to harvest mature corn hybrids in the central region of Korea. Besides yield and growth, other characteristics, such as sweetness and taste of the hybrids, should be investigated further the selection of the best corn hybrid.