Abstract
This experiment was conducted to understand the response on sowing rates at furrow sowing of rice in paddy field. As sowing rates was increased, the number of seedling stand per$m^2$ was icreased, while panicie number per plant was decreased slightly. Leaf area at heading stage and effective tiller ratio were decreased with increasing of sowing rates, but heading date was not defferent among sowing rates. According to sowing rates was increased, culm length, panicle length, breaking strength, culm diameter were decreased, while lodging index was increased. Also, field lodging was observed in the higer sowing rates over 5kg/l0a. Althougth the panicle number per $m^2$ was increased with increasing of sowing rates, spike let per panicle and percent of filled spikelet were decreased. According to the result from the path coefficient analysis, percent of filled spikelets well identified to be the most influential variables on the variability in rice yield, so that improving percent of filled spikelets by inhibition of field lodging was the important matter to increase the yield. The optimal sowing rate and the number of seedling stand were estimated to be 4.5kg/l0a and 105 per $m^2$ respectively.
벼 생력 직파재배양식으로 최근에 개발 보급된 무논골뿌림재배의 파종 피술체계확립의 일환으로 파종량에 따른 생육 및 수량반응을 검토하고자 시험을 실시하였던바, 그 결과를 요약하면 다음과 같다. 1. 파종량이 증가할수록 $m^2$당 입모수는 직선적으로 증가하였으나, 개체당 수수는 입모수 증가에 따라 완만하게 감소하는 경향이었다. 2. 유효경 비율 및 출수기 경당엽면적은 파종량이 증가함에따라 감소하였으며 출수기는 큰차이가 없었다. 3. 도복관련 형질중 간장, 수장, 좌절량, 줄기굵기 등이 파종량 증가와 함께 감소하는 경향이었고, 10a당 7kg이상에서는 포장도복이 심하게 발생되었다. 4. $m^2$당의 수수증가에 따라 수당립수와 등숙비율이 감소하였으며, 수량은 10a당 5kg을 기점으로하여 점차 감소하는 경향이었다. 5. 수량에 대한 수량구성요소의 경로계수 분석결과에 의하면 등숙비율의 직접효리가 가장컸으며, 최대수량을 얻기위한 $m^2$당 입모수는 105개 정도, 이때의 10a당 파종량은 4.5kg 수준이었다.
