The Effect of Lime Application after Cultivating Winter Forage Crops on the Change of Major Characters and Yield of Peanut

동계사료작물 재배후 석회물질 시용이 땅콩의 주요 형질 및 수량에 미치는 영향

These experiments were conducted for decrease of injury by continuous cropping in the peanut fields of Chonbuk Wangkungarea. The continuous cropping field for four years was used in this experiment. Italian ryegrass and rye were cultivated andlime materials were distributed for improvement of soil fertility. The results were as follows; 1. Forage crops were cultivatedand lime materials were distributed on the continuous cropping field of peanut. The organic matter content of the expermentalplot cultivating Italian ryegrass was only 1.25%. The organic matter content of soil cultivated Italian ryegrass after distributedmagnesium lime was 1.37% and that of soil cultivated Italian ryegrass after distributed gypsum was 1.30%. It was highcontent comparing to that of soil distributed lime materials only. The organic matter content of soil cultivated rye after distributed gypsum was 1.77%. 2. The phosphate content of soil cutivated Italian ryegrass was 332ppm. The phosphate content ofsoil cultivated Italian ryegrass after distributed magnesium lime was 34Oppm and that of soil cultivated Italian ryegrass afterdistributed gypsum was 31 2ppm. The phosphate content of soil cultivated rye only was 386ppm. The phosphate content ofsoil cultivated rye after distributed gypsum was 41 8ppm. This phosphate content was lower than that of soil distributed limematerials only. 3. The phytotoxin content of soil cultivated Italian ryegrass after distributed magnesium lime was decreased to17.7% and that of soil cultivated Italian ryegrass after distributed gypsum was decreased to 25.3%. The phytotoxin content ofsoil cultivated rye after distributed magnesium lime was decreased to 12.0% and that of soil cultivated rye after distributedgypsum was decreased to 12.8% comparing to the phytotoxin content of soil distributed lime materials only. Italian ryegrasswas effective to decrease phytotoxin among the forage crops and gypsum was effective among the lime materials. 4. Abacterial wilt and a late spot of peanut which were known as, main reason of continuous cropping failure were surveyed.lnccidence of a bacterial wilt was 3.4% in the plot cultivated Italian ryegrass only and that was 2.9% in the plot cultivated ryeonly. lnccidence of a bacterial wilt was 2.5% in the plot cultivated Italian ryegrass after distributed magnesium lime and thatwas 2.3% in the plot cultivated rye after distributed gypsum. Inccidence plot cultivated forage crops was lower than that of plotdistributed lime materials. 5. Inccidence of a late spot was high in the plot cultivated forage crops ony, but it was low in the plotcultivated forage crops after distributed lime materials comparing to that of the control plot. 6. The growth and yield of peanutwere bad in the plot cultivated forage crops only comparing to the control plot distributed lime materials only. These resultswere same in the plot cultivated rye after distributed lime materials, but the growth and yield were grown up in the plotcultured Italian ryegrass after distributed lime materials.

전북 익산군 왕궁면 땅콩 4년 연속 연작한 토양 연작장해를 감소시키기 위하여 흡비력이 강한 이탈리안 라이그라스와 호밀을 동계에 재배하고, 토양개량 효과를 증진시키기 위하여 석회물질을 시용한 결과는 다음과 같다. 1. 땅콩 연작지 토양에 동계 사료작물을 재배하고 석회물질을 시용한 결과 토양중 유기물함량은 이탈리안 라이그라스만 재배한 구 1.25%, 이탈리안 라이그라스를 재배한 후 석회고토를 시용한 구 1.37%, 석고를 시용한 대조구 1.1%에 비해 높게 나타났다. 또한 호밀만 재배한 구는 1.70%, 호밀재배후 석회고토 시용구 1.73%, 석고 시용구 1.77%로써 사료작물 재배구의 유기물함량이 높았다. 2. 인산함량은 이탈리안 라이그라스만 재배하고 석회물질을 시용하지 않은 구 332ppm, 호밀을 재배하고 석회물질을 시용하지 않은 구 386ppm, 이탈리안 라이그라스 재배후 석회고토 시용구 340ppm, 석고시용구 312ppm, 호밀시용후 석회고토 시용구 386ppm, 석고 시용구 418ppm으로써 석회물질만 시용한 대조구 549ppm 보다 월등히 낮았다. 3. 연작장해 요인중의 하나로 알려진 phytotoxin함량을 분석한 결과, 이탈리안 라이그라스 재배후 석회고토 시용구 19.7%, 석고 시용구 25.3%, 호밀 재배후 석회고토 시용구 12.0%, 석고 시용구 12.8%의 phytotoxin 감소효과를 나타냈다. 따라서 사료작물에서는 이탈리안 라이그라스가 phytotoxin 감소에 효과적이었고 석회물질은 석회고토보다 석회가 효과적이었다. 4. 연작장해의 가장 큰 요인으로 알려진 땅콩의 주요 병해인 풋마름병과 검은무늬병의 발병률을 조사하여 본 결과 풋마름병 이병주율이 이탈리안 라이그라스만 재배한 구 3.4%, 호밀 재배구 2.9%, 이탈리안 라이그라스 재배후 석회고토 시용구 2.5%, 석고 시용구 2.3%, 호밀 재배후 석회고토 시용구 2.6%, 석고시용구 2.3%로써 석회물질을 시용한 것 보다 사료작물을 재배한 것이 이병주율이 낮았고, 사료작물만 재배한 것 보다는 석회물질을 함께 사용한 것이 효과가 컸다. 5. 검은무늬병 발병률은 이탈리안 라이그라스만 재배한 구에서 5.6%, 호밀만 재배한 구에서 7.9%, 이탈리안 라이그라스 재배후 석회고토 시용구에서 4.6%, 석고시용구에서 3.4%, 호밀 재배후 석회고토 시용구에서 5.3%, 석고 시용구에서 5.2%였다. 그러나 사료작물만 재배구의 5.6%와 7.9%의 발병률은 석회물질만 시용한 대조구 5.8%와 비슷하거나 높게 나타나 석회물질을 시용하지 않고 사료작물만 재배하면 오히려 병이 조장되는 것으로 나타났다. 6. 이탈리안 라이그라스만 재배한 구와 호밀만 재배한 구 공히 석회물질만 시용한 대조구에 비해 생육상황이 나빴고, 수량도 각각 202kg/10a 및 186kg/10a로써 대조구 210kg/10a보다 낮은 것으로 나타났다. 그러나 이탈리안 라이그라스 재배후 석회고토 시용 구 및 고토 시용구는 생육상황도 양호하였고, 수량도 각각 217-225kg/10a 와 225-237kg/10a를 기록하였다.