벼 栽培樣式에 따른 綬效性 肥料의 施用量이 生育과 收量에 미치는 影響

To find out the optimum application method of slow-releasing fertilizer(SRF) and conventional fertilizer (CF) with different fertilization rate under two culture methods [10-day old seedling machine transplanting (MT) and direct-sowing on dry paddy(DS)] in the south-western region (clay loam soil) of Korea, used were Chosun slow-releasing fertilizer (silicate latex coated fertilizer : N-P 2 O 5 -K 2 O = 18-12-13) and conventional fertilizer. Plant height and number of tillers with different two culture methods were higher at MT than DS in early growth. The ratio of dry weight in heading stage was higher at CF than SRF in MT than DS and especially, SRF 80% + CF 20% than SRF 100% or CF 100%. Leaf area index (LAI) in heading stage was higher at CF in MT but higher at SRF in DS than their counterparts. Chlorophyll content was higher at SRF than in CF expect for heading stage(HS), especially in DS. It was highest at HS in CF without its difference during maximum tillering stage (MTS) and panicle formation stage (PFS), while highest at PFS in SRF with tendency of gradual increase and decrease before and after PFS, respectively. Heading was delayed 2~3 days at SRF in two cultrue methods and 4~5 days at SRF in DS in comparison with CF in MT with delay of 2 days at DS compared with MT. Culm length was longer at CF in MT and at SRF in DS than their counterparts. Panicle number per m² was more at SRF and in DS. Filled grain ratio was higher at CF and in MT. Yield was obtained 101 and 100% at 100% and 80% level of SRF in DS respectively, and 96% at 80% level of CF in MT, compared with conventional application method (516kg/10a), and increased 2~4% at DS and 0~3% at MT in SRF. Yield was high in order of 100%(SRF) = 80%(SRF) + 20%(CF) > 100%(SRF) + 20%(CF) > 80%(SRF) at MT and 80%(SRF) + 20%(CF) = 100%(SRF) > 80%(SRF) = 100%(SRF) + 20%(CF) at DS.