Abstract

Concerns on use of excess amount of chemical fertilizier and pesticide in current farming system turns both of the producer and consumer of agricultural products to an organic farming which use a less chemicals and more natural manure. Rice-duck farming system is one of the strategy to meet the purpose and this experiment was carried out to find the effect of the rice-duck farming system on the quality and yields of rice. 20day-old rice seedling were mechanically transplanted in sandy-loam paddy field and 21 day-old ducks were raised from 3 weeks after transplanting with population of 30 heads per 10a. The plots were consists of reduce fertilizer(70%) with and without duck-raising. The conventional fertilizer treatment without duck-raising was used as check. The results obtained are summarized as follows. The weeds population of test plots which were raised with duck for 3 consecutive years was less than that of test plots without duck-raising, though a speciffic population of Echinochola crusgallis were increased. The weed control effect was higer in duck-raising than in check at the maximum tillering stage but, not at later stages of rice plant. It was found that the small animals and insects inhibiting in the rice field were reduced by duck-treatment, however, there were also damages of grass leaf roller at booting stage in the plots of duck-raising. In rice-duck plot, dark green leaf color were found: 41.8 of SPAD value than 38.6 of SPAD in check plot. Higher root activity and surface soil oxidation were also observed in rice-duck plot than check plot. 3% of the increase in yield was observed by duck-treatment. However, the expected increase of the palatability wsa not observed. This may be due to the unfavorable weather conditions during the rice growing in this expriment.

오리방사에 의한 화학제 기능대체 효과와 유기미의 수량 및 품질을 검토코자 사양질답에 관행 시비량의 70%를 감비하고 일품벼를 중묘 이앙하여 이앙 3주후에 3주령오리를 10a당 30마리 밀도로 방사하고 무농약으로 재배하여 시험한 결과는 다음과 같다. 1. 오리 3년차 방사논의 방사 직전 잡초 발생수는 무방사구보다 거의 반으로 줄어들었으나 피의 발생은 오히려 현저히 증가되었고 최고분얼기 잡초방제가는 관행 88%보다 92%로 높았으나 그 이후에 피의 방제는 효과가 적었다. 2. 오리 방사는 벼물바구미와 멸구류, 기타 곤충등과 소동물을 거의 포식하였으나 수잉기에 발생된 혹명나방피해는 방제하지 못하였다. 3. 오리 방사구는 관행구보다 표면수가 항상 현탁되어 있고 표층토의 산화환원전위차가 높아 유수형성기의 엽색이 관행 38.6보다 41.8로서 더 짙은 녹색을 유지하였으며 등숙기 까지 높은 근활력을 유지하였다. 4. 오리 방사구에서는 유기미 쌀수량이 648kg /10로서 관행구보다 3% 증수되었고 생산된 유기미는 '94년 고온년의 특이성으로 청미비율이 높아 관능검사에 의한 식미는 약간 나쁜 경미한 차이를 보였다.

Keywords

• Rice-duck farming;
• Weed control;
• Insect pest control;
• Reduction of fertilizer;
• Rice quality