溫度對鳥梨實生後裔幼苗生長之影響

Effect of Temperature on Plant Growth of Lindley Pear (Pyrus lindeyi Redh.) Seedlings

採自卓蘭與大湖地區之鳥梨開放授粉種子，經2週5℃處理後，播種取得之實生後裔以6吋盆種植，置於日夜溫分別為30/25℃、25/20℃、20/15℃、15/13℃之生長環境下，並以自然條件作為對照比較其生長狀況。初期（100日內）生長隨溫度之增高而增加，處理150日後，20/15℃以上及自然狀況之植株生長急速減緩，但在15/13℃處理生長速率維持不變，甚至於略增，導致其在處理結束後，其株高反而最高。各處理間節數差異不大，但節間長度明顯隨著溫度上升而縮短，此外，幹徑、幹截面積間呈一次迴歸，枝刺數、分枝數均會因溫度之不同而改變。卓蘭地區鳥梨之株高與節數、節問長度、幹徑和幹截面積之相關性均可達極顯著或顯著水準，且較不受溫度所影響；大湖地區鳥梨則在幹徑與截面積之表現比較穩定。由試驗結果顯示，二地區鳥梨在表現型上的差異極大，且部份性狀會隨著溫度而改變，故以高度為選拔目標時，溫度變級的處理應是必要的措施。

The open pollination seedlings of Lindley pear from Chuo-Lan and Do-Hu area were treated under 5℃ for two weeks, planted /n 6-inch pots. The seedlings were treated with day/night temperature of 30/25℃. 25/20℃, 20/15℃. 15/113℃ (day/night℃), with the field condition as the control. At the beginning the growth and growth rate of the seedlings were proportional lathe temperature. After 150 day's treatment. the growth rate of above 20/15 temperature treatments and control was decreased sharply. On the contrary, the growth of 15/13℃ treatment remains steadily or slight increased, resulting in the greatest plant height when the experiment completed. The number of nodes under different treatment was close to each other. The length of internode decreased significantly with increasing temperature. Also, the stem diameter, the cross Section area of the stem, the number of thorns and branches all differ under different treatment. Plants collected Bum Chao-lan. showed constant and high significant linear regression and high multiple correlation coefficient between plant height and other 4 characters. Which was number of nodes, length of internode, stem diameter, and trunk crass section area in all treatments. While in the population collected from Da-hu, temperature seemed more affective in the relationships between plant height and ether characteristics. The resells results that the phenotype is quite different between Chua-lan and Da-ha Lindley pears' seedlings and some plant characteristics would be affected by temperature. Therefore it is necessary to treat the selected population with temperature be sure their performances, especially plant height.