Influence of Meterological Factors On Soybean Seed Size in Southern Korea.

Seed size of soybean is an important agricultural characteristics which influences on marketing price in Korea. To analyze meteorological factors influencing seed size, seeds of three varieties, Daol(MGII), Daewon(MG V) and Daepung(MG V) were sown from April 30 to June 30 at 20 day interval in two regions, Miryang(35°48′N128°73′E, alititude : 12m) and Muju(36.°00′N127°71′E, altitude : 600m) during two years from 2005 to 2006. We divided into three reproductive growth periods, from R2 to R4, from R4 to R6 and from R6 to R8 to analyzed multiple regression(stepwise) for seed size. The estimated regression equations for each soybean were as follow; Dawon = 90.8-1.89×Mean temp.(R2-R4)-0.71×Mean temp.(R4∼R6), Daepung= 52.8-1.22×Mean temp.(R2∼R4)-0.006×Rainfall(R2∼R4) and Daol= 56.1-0.935×Mean temp.(R2∼R4). Those equations were able to estimate seed size of Daewon , Daepung and Daol varieties with 98.1%, 96.6% and 81.3% probability, respectively. This result could be useful for selection of proper soybean cultivation site for high quality soybean production.