Effects of leaf-defoliation and different nitrogen, phosphorus and potassium application on maturity and yield of rice

질소 인산 가리의 시용량의 차이 및 전엽처리가 수도의 등숙 및 수량에 미치는 영향

Field experiment was conducted to disclose some effects of leaf defoliation in heading time and the application of different combinations of nitrogen, phosphorus and potassium on the maturity and yield of paddy rice. The results obtained are as follows; 1.All were components considered were increased as the amounts of nitrogen, phospgorus and potassium applied were increased, except the maturity rate had the tendancy to be decreased with the increase of the above fertilizer applications. 2.As the rate of cutting leaves went higher, the weight of rough rice, the maturity rate and the weight of 1, 000 kernels of perferct brown rice were decreased, and there were significant differences among the treatments of leaf blade cutting. 3. The contribution of each leaf to yield through the maturity, number of spikelets per panicle and 1, 000 kernel weight were 61.87-66.18-65.61% respectively for the flag leaf, 17.50-20.65-23.41%for the 2nd leaf, 12-71-12.73-10.11%for the 3rd lead and 7.93-6.44-0.87%for the 4th leaf respectively. This simply indicared that the effects of the leaves to the yield were decreased as their position went down. This tendency was specially emphasized in the case of the weight of 1, 000 kernels of perfect brown rice.

1. 질소 인산 가리의 증시에 따라 수량구성요소는 각각 증대되였으나 등숙률만은 질소의 증시로 저하되는 경향이었다. 2. 전엽의 정도가 클수록 정조중 등숙률 및 완전현미 1,000입중이 저하되었으며 전엽처리간에 유의차가 인정되었다. 3. 엽위별 엽신이 등숙률 정조중 및 완전현미 1,000 입중을 통한 생산에 미치는 영향은 지엽이 61.87-60.18-65.1%, 제2위엽이 17.50-20.65-23.41%, 제3위엽이 12.71-12.73-10.11%, 제4위엽은 7.93-6.44-0.87%로서 하위엽일수록 그의 생산효과가 낮아지는 경향을 보였다.