신간척지에서 염해경감 및 등숙률 향상을 위한 완전낙수시기 구명

Establishment of Perfect-Drainage Period for Reduction of Salt Injury and Improvement of Grain Filling Ratio in the Newly Reclaimed Land

This research was carried out to establish perfect-drainage time in order to stabilize rice yield and improve rice quality. Treatments of perfect-drainage were conducted 5 days interval during 25 days to 50 days after heading date in the field of Saemangeum Gyehwa, newly reclaimed land. Accumulated temperature after heading date in 2010 increased about 100℃ and precipitation amount decreased a little compared to normal year harvesting time. Average panicle number was 16.5 and spikelet per panicle was 88. Perfect drainage time treatment after 40~50 days was 3% higher in percent ripened grain and 0.6 g heavier in 1,000 grain weight than treatment after 25~35 days. There was no difference of rice yield between perfect drainage time treatment after 25 days and 30~35 days, but rice yield was 7~8% higher in treatment after 40~50 days than 25 days. Head rice ratio in treatment after 35 days was the highest and the sooner perfect drainage time, the lower protein content. Soil moisture negatively correlated with soil hardness and EC in this result. With this results, we proposed that the time of perfect drainage in newly reclaimed land to stable rice production is 40~50 days after heading date.