溫度對不同粒重水稻品種頴果浸潤、澱粉－分解酶活性及秧苗生育之影響

Temperature and Grain-Weight Effects on the Imbibition and Amylase Activity of Caryopsis and Seedling Growth in Rice

劉大江(D. J. Liu) ； 魏夢麗(M. L. Wei) ； 林淑雰(S. F. Lin)

《中華農業研究》 37卷3期 (1988/09) Pp. 239-249

https://doi.org/10.29951/JARC.198809.0002

摘要

本試驗採用大粒型水稻品種Pegonil與中粒型栽培品種臺農67號爲材料，探討溫度處理（15、25與35℃）對穎果浸潤吸水能力與澱粉分解酶活性之影響；又於生長箱及田間培育秧苗，比較在不同溫度下之生長勢，以明瞭溫度與粒重對水稻穎果及幼苗生育生理的可能作用。Pegonil單一穎果重爲臺農67號之兩倍，以單一穎果爲基礎表示時，其浸潤吸水速率自然較高，但澱粉分解酶活性之差異則較不顯著；如改以單位重穎果爲基礎表示，在較低溫(15℃)時Pegonil仍具有較臺農67號爲高之吸水能力與酵素活性，並與高溫時之表現有異，顯示此一大粒型品種對低溫的特殊適應性。在28/20與23/15℃生長箱及第一期作田間低溫環境下，Pegonil秧苗之苗高、葉面積、可溶性蛋白質濃度及鮮、乾物重均顯著優於臺農67號，亦即具有較佳的生長勢；秧苗C/N比值變異未能用以解釋生長勢之差異，但Pegonil品種的苗重與苗長比值較高，而高浸潤速率與澱粉分解酶活性亦可能爲低溫下秧苗生長快速的部份原因。試驗結果建議應確切瞭解不同粒重水稻種源對低溫的適應性，並在耐冷性研究方面兼重存活能力與秧苗生長勢，或有助於第一期作培育適於機插之秧苗及移植後早期在低溫環境下之本田生育。

並列摘要

One large-grain rice variety, Pegonil and one medium-grain variety, Tainung 67 were used in this experiment to study the influence of temperature on the imbibition rate and amylase activity of caryopsis and seedling growth vigor. Weight per grain of Pegonil was two times higher than that of Tainung 67 and thus a higher water uptake rate per grain was observed upon imbibition of the caryopsis. However, the difference in amylase activity per grain was less clear. If the results were expressed on a per unit weight of grain basis, Pegonil variety still showed higher water uptake rate and amylase activity than Tainung 67 at 15℃ which were different from the results of higher temperature treatments, indicating special adaptability of the large-grain variety to low temperature. Growth-chamber study at 28/20 and 23/15℃ and field study under low temperature of the first crop season showed that plant height, leaf area, soluble protein concentration, and fresh and dry weight of Pegonil seedlings were significantly higher than those of Tainung 67, or a superior seedling vigor was observed. Result of C/N ratio failed to explain the difference in seedling vigor between varieties, whereas higher weight/height ratio, water uptake rate and amylase activity may be used, at least in part, as the mechanism of high seedling vigor of Pegonil variety cultivated under low temperature. Experimental results suggested that a better understanding of the caryopsis and seedling response to temperature by large-grain varieties is meaningful. Furthermore, the use of seedling growth vigor in addition to survival rate in the study of chilling injury on rice might be essential to seedling nursery and adaptation of rice plants after transplanting in the first crop season when low temperature prevails.