大果木蓮種子萌發及其生理特性1)

李宗艷　　　　　　肖娟

(西南林業大學，昆明，650224)　　　　(云南森林自然中心)

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大果木蓮種子萌發及其生理特性1)

李宗艷肖娟

(西南林業大學，昆明，650224)(云南森林自然中心)

摘要以大果木蓮種子為材料，比較赤霉素(GA3)浸種、磨破種皮和層積40 d種子萌發特性和萌發生理代謝差異，結果表明：冷藏1個月的大果木蓮種子在較佳萌發溫度25 ℃/15 ℃(晝/夜)下，種子萌發率僅為21.33%；當GA3質量濃度達到800 mg·L(-1)時，種子萌發率均超過53%，且差異不顯著，萌發率受溫度的影響不大；GA3處理能有效提高在非萌發適溫下種子的發芽指數，但對萌發適溫下的種子發芽指數無顯著促進效果。磨破種皮和層積40 d處理對提高種子萌發率無顯著作用。隨著萌發進程，800 mg·L(-1)GA3處理能顯著地提高種子內可溶性糖質量分數和過氧化氫酶(CAT)活性，清除體內的丙二醛(MDA)，但對過氧化物酶(POD)活性無明顯影響；層積組和對照組種子的可溶性糖質量分數、CAT和POD活性隨萌發進程的變化無明顯差異，僅在清除MDA的速度上，層積組要優于對照處理。在大果木蓮種子萌發的生理代謝變化中，CAT活性與可溶性糖質量分數變化呈極顯著正相關，可溶性糖質量分數與MDA質量摩爾濃度、CAT活性與MDA質量摩爾濃度之間均呈極顯著負相關；經主成分分析，CAT、POD活性的變化對種子發芽的貢獻較大。

關鍵詞大果木蓮；種子萌發率；過氧化氫酶；生理代謝

分類號Q945.53

Seed Germination and Physiological Characters ofManglietiagrandis

Li Zongyan

(Southwest Forestry University, Kunming 650224, P. R. China); Xiao Juan(Yunnan Nature Conservation Center)//Journal of Northeast Forestry University，2016,44(3)：37-41.

We studied the germination characters and physiological metabolism ofManglietiagrandisunder the GA3-soaked, seed coat-destroyed and 40-d cold stratification treatments. The germination rate of 30-d cold storage seeds reached to 21.33% even under the appropriate temperature. Seeds soaked with GA3had higher germination rate which was related with its concentration and temperature. Seed germination rates were above 53% and had no significant difference under all three temperature when seeds were soaked with 800 mgL-1GA3. Germination index could be effectively increased in no suitability temperature, but not increased significantly in an appropriate temperature. Germination rate had no significant difference under seed coat-destroyed and 40-d cold stratification treatments. Soluble sugar content and CAT activities were increased effectively and MDA was quickly cleaned under GA3treatment, while POD activity was kept stably. But soluble sugar content, CAT and POD activity had no significant difference between cold stratification and contrast treatment, except a quick clearance of MDA in cold stratification. CAT activity had a significant positive-correlation with soluble sugar content. Otherwise, there was a negative correlation between soluble sugar content and MDA content, and between CAT and MDA. By the principle component analysis of four physiological indexes, CAT and POD activity had much more contribution rate to seed germination.

KeywordsManglietia grandis; Germination rate; CAT activity; Physiological metabolism

種子的萌發受種子特性和環境因素的影響，種子萌發數量決定種群的更新能力。瀕危物種就是不能依靠繁殖來維持野外生存的最小種群數量的物種。……