초록
비닐피복작물 재배시 시비효율 증대 및 생력시비기술 확립을 목적으로 토중시비기를 개발하였고 2000년 부터 2001년까지 2년 동안 이를 이용하여 양파를 재배한 후 토양개량, 양분이용률 및 수량성에 미치는 영향을 평가하였으며 그 결과는 다음과 같다. 시험 전 토양보다 모든 처리에서 치환성칼륨 함량은 증가되었으나 유효인산 함량은 감소되었다. 생육시기별 토양 중 질산태질소 함량은 모든 처리에서 생육초기에 가장 높았으며 특히 관행시비에 비하여 토중시비에서 $30-60mg\;kg^{-1}$ 높았고 3회 추비에서 생육후기까지 높게 발현되었다. 양파의 생장속도는 토중시비에서 높았고 생육중기 이후 차이가 크게 나타났으나 토중시비 추비횟수 사이에는 유의성이 없었다. 시비질소 흡수량은 관행시비($78kg\;ha^{-1}$)에 비하여 토중시비에서 59-69% 많았고 질소이용률은 추비 2회>추비 1회>추비 3회 순으로 18-20% 높았다. 시비칼리 흡수량은 관생시비($63kg\;ha^{-1}$)에 비하여 토중시비에서 52-71% 많았으며 칼리이용률은 13-17% 높았다. 시비방법별 시비질소 잔존량은 관행시비에 비해 토중시비에서 8-14% 많았고 시비질소 손실량은 관행($154kg\;ha^{-1}$)에 비해 토중시비에서 26-34% 적은 반면에 시비칼리 잔존량은 13-18% 많았고 시비칼리 손실량은 29-31% 적었다. 양파 생육 및 수량은 토중시비에서 엽초경과 구경이 굵고 구중이 무거워 관행시비($45.91Mg\;ha^{-1}$) 대비 7-13% 증수되었으며 질소시비효율이 22-42% 증대되었다.
It is very important to improve fertilizer use efficiency for the saving of fertilizers and for environmental purposes as well. However, there was no effective ways for the fertilization in the mid of growth under the plastic film mulching cultivation so far. For this, a Band Spotty Fertilization (BSF) machine was developed recently. So, we tried to establish a low input fertilization technique using this BSF machine in the vinyl mulching cultivation of onion (Allium cepa L.). Fertilization efficiency, soil properties, and crop yield were examined and compared among treatments from 2000 to 2001. The content of exchangeable K in soils were higher after fertilization but that of available $P_2O_5$ was lower than before the experiment in all plots. The content of nitrate-N was highest at the early growth stage, and higher in BSF plots than that of conventional fertilization (CF). BSF plot showed higher growth rate, and uptake amount of nitrogen of onion by 59-69% than that of CF. N use efficiency in BSF was higher in the order of two time-split application, one time-split application, and three time application. K use efficiency was high 13-17% BSF plots than that in CF($63kg\;ha^{-1}$) plots. The amount of residual N in soils was high by 8-14% in BSF plots compared to that in CF plots, and the loss of N was lowered 26-34% by BSF. Also, the amount of residual K in soils was high by 13-18% and the loss of K was low by 29-31% in BSF plots compared to that in CF plots. The yield of onions increased by 7-13% by BSF due to increased diameter and weight of bulbs. As the results, N fertilization efficiency increased by 22-42% by BSF.
