Effect of Nitrogen Split Application on Growth and Quality of Okro Tea Leaves(Camellia sinensis var. sinensis)

질소 분시횟수가 옥로차엽의 생육과 품질에 미치는 영향

The split application of a nitrogen fertilizer was applied at the levels to 3, 4, 5, 6 and 7 time. The results of yield and quality of Okro tea are summarized as follows: Among five treatments, the growth and yield were somewhat more excellent in the five time split treatments compared with other treatments. The chemical components such as total nitrogen, total amino acid and vitamin C were somewhat higher in the five time split treatment compared with other treatment. However, the content of components such as tannin, caffeine, chlorophyll were not different among plots of $4{\sim}7$ time split application except three time split application manuring. The content of fatty acid was producted $2,888{\sim}2,933mg/100g$. Especially, the content of oleic acid, linoleic acid and linolenic acid was the higheat in the five time split application. Sixteen kinds of free amino acid including theanine as a good taste component of Okro tea were isolated and measured by HPLC. Theanine in the five time split application was higher with value of $72{\sim}513mg/100g$ than in other treatment. In scoring test, tea appearance and interal qualities of 3 time split application become lower than any other treatment as 80.2 point, while five time application had the highest with 84.7 point. Conquently, those results meant that five time split application was optimum split application of fertilizer for high yield and good quality of Okro tea.

질소비료를 $3{\sim}7$회 분시하여 옥로차의 수량 및 품질을 분석한 결과는 다음과 같다. 5회 분시가 타처리에 비해 생육과 수량이 많고 타처리에 비해 총질소, 총아미노산, 비타민C 함량이 약간 많았으며 탄닌, 카페인, 엽록소, 총유리당 함량은 3회분시를 제외하고 $4{\sim}7$회 분시에서 거의 차이가 없었다. 지방산 함량은 $2,888{\sim}2,933mg/100g$이었고, 특히 5회 분시에서는 oleic acid, linoleic acid, linolenic acild 함량이 가장 많았다. 옥로차 감칠맛 성분인 theanine을 포함해 16종이 아미노산을 분리 정량한 결과 5회 분시가 타처리에 비해 theanine 함량이 $72{\sim}513mg/100g$더 많았다. 관능평가에서 3회 분시가 80.2점으로서 다른 처리보다 낮았고, 5회 처리가 84.7점으로 가장 높았다. 결론적으로 5회 분시처리가 다른처리에 비해 수량도 양호하고 차 품질도 우수하여 옥로차의 적정 분시첫수라고 생각된다.