벼의 수량과 품질은 등숙기의 고온에 의해 영향을 받는다. 본 연구는 남부지방에서 벼 조기재배로 인한 고온 등숙에 벼의 수량과 미질이 적합한 벼 품종 선정을 위하여 수행하였다. 조생종 14품종을 파종 후 20일인 4월 20일에 이앙하여 수확 후 수량과 도정된 쌀의 품질을 조사하였다. 쌀 수량은 단위 면적 당 영화수가 가장 많았던 운광이 가장 많았고 주남조생, 조광, 황금보라, 만나, 운미, 밀양238 및 조아미 순이었다. 완전미 수량은 밀양247이 가장 높았고, 조광, 만나, 산들진미 순이었다. 단백질 함량은 6.0∼6.9% 범위를 나타내었고, 밀양247, 산들진미, 조아미, 만나, 보석 및 조광 품종이 취반미윤기치가 비교적 높게 나타났다. 따라서 남부지방 평야지 벼 조기재배시 산들진미, 조광, 만나 그리고 밀양247이 적합한 품종으로 판단된다.

Chinese milkvetch(CM) has been cultivated as green manure source for environment friendly farming in southern area. This experiment was conducted to produce good quality rice through studying the changes of yield, quality and leaf colors as affected by the amount of CM biomass retuned to paddy field. We growed rice, transplanted in June 10 with cultivar dongjinilho, in four different plots retuned green manure with 0, 1.5, 3.0, and 4.5 ㎏ m-2 CM biomass in May 30. Nitrogen amounts were 5.5g by 1.5㎏CM biomass, 11.1g by 3.0㎏, and 16.6g by 4.5㎏ in late May. There were no different SPAD values among treatments in 10 days after transplanting. However, the more the CM biomass from 20 days after transplanting, the higher the SPAD values were. the plot of CM biomass to 3.0 ㎏ m-2 had same heading date but the plot of 4.5 ㎏ m-2 was one day late heading date as compared with the others. There were no different plant height, number of panicle, panicle length, number of leaf and ripening ratio among the CM biomass amounts. The higher the CM biomass amount, the more likely the plant was lodge. the plot retuned CM fresh biomass 1.5 ㎏ m-2 showed the higher rice yield than the plot retuned 3.0 and 4.5 ㎏ m-2 in 2006, but all plots had similar rice yields in 2007. There was no different whiteness of rice among all treatments . The more the CM biomass amount retuned to plot, the higher the protein content of rice.