Effects of Root Restriction on Carbohydrate Metabolism in Tree Peony（Paeonia suffruticosa） Leaves | 根域限制对牡丹叶片碳代谢的影响

Chinese. 以‘洛阳红’牡丹为材料,研究根域限制（盆栽）对牡丹叶片碳代谢的影响。结果表明：根域限制能显著降低牡丹叶片的净光合速率（Pn）,蔗糖磷酸合成酶（SPS）和酸性转化酶（AI）的活性。根域限制下,牡丹叶片中SPS和AI活性的降低表明其源强和库强都受到抑制。盛花期之前,牡丹叶片中蔗糖、淀粉的含量显著低于对照（大田栽培）;从盛花期到开花后期,库强拉动蔗糖运输到库器官的动力不足,淀粉水解少,蔗糖、淀粉在叶片中累积;盛花前后己糖变化平稳,含量总体低于对照。库强小是牡丹Pn降低的主要原因,还与叶面积小和碳水化合物在叶片中的累积有一定的相关性。

English. This study analyzed the effect of root restriction（potted cultivated） on carbohydrate metabolism in ＇Luoyanghong＇ tree peony（Paeonia suffruticosa luoyanghong） leaves.The result showed that root restriction significantly reduced the net photosynthetic rate（Pn）,sucrose phosphate synthase（SPS） activity and acid invertase（AI） activity of tree peony leaves.The declined SPS activity and AI activity in tree peony leaves showed that both source and sink strength were inhibited by root restriction.Before anthesis,sucrose and starch levels were significantly lower in root restriction tree peony leaves than that in control.However,from flowering-stage to late-flowering stage,sucrose and starch were accumulated in root restriction tree peony leaves mainly because of the low sink strength which limited the driving force to transport sucrose to sink organ and to hydrolyze starch.Hexose content in root restriction tree peony leaves were lower than the control overall and its change was smooth during anthesis period.The reduced Pn of root restriction tree peony was mainly because of the lower level of sink strength,and the reduction of leaf area and accumulation of carbohydrates in leaves can also explain it to a certain extent.