哈密瓜採收成熟度之研究

Studies on the Maturity Indices of Hami-Gua Melon

李國明(Kuo-Ming Lee) ； 呂文通(Wen-Tong Leu) ； 王自存(Tsu-Tsuen Wang)

《花蓮區農業改良場研究彙報》 5期 (1989/05) Pp. 15-16

摘要

本研究係為探討哈密瓜在其不同生育過程間之生長、開花、結果之習性，並調查其物理及化學性狀之變化，以供訂定果實採收成熟度之指標，確定品質與熟度。試驗工作於民國77年春作辦理，品種為新世紀哈密瓜，4月9日植於本田，經15天後摘心，留本葉三葉，分枝數為3枝，定植後36天花器出現，而40天後為開花期，開花翌日為落花期，雌雄花數之比為雌花佔9.6%。試驗結果，哈密瓜果實生長發育過程中之果重變化，由開花後5天調查為14.98公克，經40天時為3,435公克。果長方面，開花後5天僅3.10公分，經25天後為19.03公分，果實成長快速呈顯著變化，開花後25天到40天為成熟階段，果長的變化則不顯著。果寬方面，由開花後5天的1.35公分到40天的17.90公分，各生長階段均呈顯著差異。果實網紋之變化，著果初期幼果皮有絨毛，開花後10天消失而出現平面無凸起的細網紋，20天起則有凸起之網紋明顯展開，35天時網紋為60∼80%，開花後40天果實網紋可達85∼100%。果實糖度測定結果，開花後5天為4.35°Brix，經40天後為12.18°Brix。本試驗於開花後30天開始測定果實硬度，將果皮削去2公厘測定果肉硬度，30天為7.05公斤，35天為4.38公斤，40天則為3.40公斤，果實硬度減低，表示果實成熟度增加，並逐漸軟化。綜合上述結果，宜蘭地區之哈密瓜採收期為開花後35天左右，此時果重約2.5到3公斤，果皮網紋面積80%左右，果皮色澤由墨綠色轉青綠色，果肉顏色呈橙黃色，果實硬度約4∼5公斤，而糖度在11°Brix以上。

並列摘要

This experiment was codcucted for the prupose of obtaining information regarding growth and maturation of Hami-Gus Melon. Growth habits and changes in physical and Chemical characters of the fruit of Hami-Gua Melon at different stages of growth were investigated. The results were as follows: After flowering, fresh fruit weight increased from 14.98 gm at 5 days to 3,435 gm at 40 days. Fruit length was 3.10 cm at 5 days and 19.03 cm at 25 days. Rapid growth in fruit length was observed during the period from the day of flowering to the 25th day. The width of the fruit, increased from 1.35 cm at 5 days to 17.90 cm at 40 days. There were significant differences among all stages of growth, At young fruit stage there were only fine haire on the surface of the fruit, which is about 10 days after flowering. Followed by the development of flat net-stripes. Significant projection of net-stripe began to form at the 20th day. By the time of the 35th day, 60-80% of the fruit surface were vovered with net-stripes and corresponded to about 70-80% of full maturity. Net-stripes were completely formed by the 40th day. Sugar content increased from 4.35°Brix at 5th day to 12.18°Brix at 40th day. Firmness of the fruit, which was measured after peeling off 2mm of skin, was 7.05, 4.38 and 3.40 kg at 30th, 35th and 40th day, respectively. The gradual decrease in the firmness of the fruit reflected that the fruit was progressing toward maturation. In conclusion, the optimum harvesting date for Hami-Gua Melon is around 35 days after flowering. During this stage the fruit weight is 2.5-3 kg, 80% of its surface has developed netstripe, the color of the fruit skin has changed from dark green to light green, and the pulp color is orange-yellow, the firmness of the flesh is around 4-5 kg, and the sugar content of the pulp is above 11°Brix.