Effects of Summer Temperature and Nitrogen Application on Carbohydydrate and Fiber Contents in Orchardgrass Stubble

하계기온 및 질소시용이 Orchardgrass 그루터기의 저장탄수화물과 섬유소함양에 미치는 영향

This experiment was carried out to compare the effects of summer temperature and nitrogen application on carbohydrates and fiber contents in orchardrass stubble grown in the cool summer year, 1980 and in the hot summer year, 1984. For this study, the contents of carbohydrates, neutral detergent fiber (NDF), acid detergent fiber(ADF) and hemicellulose in orchardgrass stubble were investigated. 1. Total water soluble carbohydrates(TSC) in orchardrass stubble were accumulated during the period of cool season and were declined when the weather was hot and dry. The reserve level of those were decreased when a new leaf emerged after the start of plant growth and then were increased as the plant was in full flourish. 2. The reserve of carbohydrate content in orchardgrass stubble was about twice times higher in cool summer year than that in hot summer year, and the reserve rate of carbohydrates showed to be fast in cool summer year. When the nitrogen fertilizer applied, the content of TSC in orchardgrass stubble more lowered but not significantly different(p<0.05). 3. The contents of NDF, ADF and hemicellulose in orchardgrass stubble in cool summer year were not significantly different from those in hot summer year. These contents showed also no significant difference among different levels of nitrogen applications. 4. The relationship of carbohydrate, NDF, ADF and hemicelluose contents according to the levels of nitrogen applications were negatively correlated in cool summer year. But there was no consistency in hot summer year.

본 연구는 하계기온 및 질소시용이 orchardgrass 그루터기의 저장탄수화물과 섬유소함양에 미치는 영향을 구명하기 위하여 냉해가 심했던 1980년과 하고현상이 심했던 1984년의 자료를 비교 검토할 목적으로 수행되었는데 orchardgrass 그루터기에 있어서 탄수화물함양과 NDF, ADF 및 hemicellulose의 함양을 대상으로 비교분석하였다. 1. Orchardgrass 그루터 기의 수용성탄수화물함량은 서늘한 계절에 축적되었고 고온기간에 감소하였다. 그리고 생육을 개시한후 신엽발생시 감소한 다음 생육이 진전됨에 따라 증가하였다. 2. 여름철 orchardgrass 그루터기의 저장탄수화물함양은 냉해가 심했던 년도가 하고가 심했던 년도의 두배정도 높았고, 저장속도가 더 빠르게 나타났다. 그리고 저장탄수화물함양은 질소시용에 의하여 낮은 경향을 나타냈으나 유의차는 없었다(p<. 05). 3, 여름철 orchardgrass 그루터기의 DNF, ADF 및 hemicellulose함양은 냉해가 심했던 년도와 하고가 심했던 년도간에 큰 차이가 없었다. 그러고 질소시비수준에 의해서도 차이가 나타나지 않았다. 4. 여름철 시비수준별 orchardgrass 그루터기의 탄수화물함양과 NDF, ADF 및 hemicellulose함양과의 상관관계는 냉해가 심했던 년도에는 모두 부의 상관관계 경향을 나타났으나 하고가 심했던 년도에는 일관성이 없었다.