中部地區酪梨乾物變化趨勢及到達最低採收成熟度時間初報

Trend of Dry Matter Weight Change on Avocado for Minimum Harvest Maturity in Central Taiwan

徐錦木(Hsu, Ching-Mu)

《臺中區農業改良場研究彙報》 151期 (2021/06) Pp. 1-12

摘要

酪梨果實在樹上不會後熟的生理特性，在採收時均為不可食用的狀態，栽培者如何判斷果實的生理成熟度，是產業發展上的一個重要的課題。本研究以2020年在海拔高度19m的彰化縣大村鄉與海拔376m臺中市東勢區為採樣區，分別在該品種成熟期前開始，隔週採取樹上較大的果實進行分析。酪梨果實乾物（dry matter, DM）與油脂含量（oil content, OC）隨著生長時間增加有緩慢上升的趨勢，到一定時間後上升趨勢會轉為平緩不再上升，但在外觀上並無明顯的變化。臺中市東勢區的‘哈斯’（hass）品種在10月中旬，‘佛也得’（fuerte）在9月下旬，‘平克頓’（pinkerton）在10月上旬，達到美國加州建議的最低採收DM以上，彰化大村的‘嘉選3號’在7月下旬，‘厚兒’（hall）在10月中旬DM也能達到20%以上，但‘黑美人’則無法達到20%以上。栽種地的海拔高度對於同一品種成熟度會有影響。本研究結果顯示‘黑美人’、‘嘉選3號’及‘厚兒’3個品種DM到達同一數值的時間，在海拔較低的大村地區較東勢地區（海拔高度差350m）提早約2－4星期，此項特性也會影響國內不同產地酪梨採收時間。國內酪梨品種需累積更多資料才能訂出適合的採收期標準。

關鍵字

乾物重 ； 油脂含量 ； 品種 ； 成熟度

並列摘要

The physiological characteristics of avocado fruit that will not ripen on the tree are inedible until harvested. How to distinguish the physiological maturity of the fruit is a crucial subject on the avocado industry. This experiment was conducted at Dacun Township, 19 m above sea level in Changhua Coutny, and Dongshi District, 376 m above sea level in Taichung City in 2020. The larger fruits of every variety were taken for analysis every other week before the maturity. The percentage of dry matter (DM) and percentage of oil content (OC) of avocado fruit have a slow upward trend with the growth time and then reaches a plateau. However, there is no obvious change in appearance. In Taichung Dongshi, it shows that the time for every variety to reach the minimum DM recommended by California is as follows: 'Hass' in mid-October, 'Fuerte' in late-September and 'Pinkerton' in early-October. In Chunghua Dacun, 'Jiaxuan No. 3' in late-July and 'Hall' in mid-October can reach the minimum DM of 20%, but 'Black Beauty' cannot. The experiment indicates that the altitude of the planting area will affect the maturity of avocado for the same variety. 'Black Beauty', 'Jiaxuan No.3' and 'Hall' in Dacun take approximately 2-4 weeks earlier to reach the same value of DM than in Donsshi with the altitude difference of 350 m. This result will be the reference to the harvest time of avocado in different production areas in center Taiwan. Finally, it's worth devoting more research to provide an commercial criteria on avocado maturity.

並列關鍵字

dry matter (DM) ； oil content (OC) ； variety ； maturity