兰州市园林树种晚霜冻害与国槐霜前疏枝桩橛萌蘖现象观察

The Observation of Freezing Damage to Landscape Tree Species and Germination of Branch-thinning Deadman of Sophora japonica before the Frost in Lanzhou

2018年4月5日,兰州市发生晚霜冻害。观察记录到市区内52种(品种)园林树种遭受冻害,受害器官及其受害程度、当年坐果能力受损程度因树种而异;春发嫩枝全部受冻干枯的树木均能再次发芽抽生新枝,重建枝冠叶幕;所见豆科树种绝大多数遭受冻害;霜前疏枝的国槐植株大量发生桩橛萌蘖现象。分析认为,受害树木再次发芽、霜前疏枝国槐植株桩橛萌蘖均为冻害消除顶端优势所致。进而提出形成层屏蔽模型,圆满解释了原发顶端优势形成与作用机制,以及树木萌蘖现象。

Late frost damage occurred in Lanzhou on April 5,2018.It was observed and recorded that 52 kinds(varieties)of landscape tree species in the urban area suffered from cold injury,and the damaged organs and their degree of damage,the degree of damage to the fruit-setting ability of that year vary according to the tree species;All the frozen and dried trees can sprout again to produce new branches and rebuild the canopy and leaf curtain;The vast majority of leguminous tree species suffered from cold injury;A large number of plants of Sophora japonica have sprouted with branch-thinning before the frost.And the analysis says,all of the germination of the affected trees and the Sophora japonica tillering were caused by freezing damage eliminates the apical dominance.The cambium shielding model was proposed to explain the formation and mechanism of primary apex dominance and the phenomenon of tree tillering.