苗木假活假死的理论分析

The Theoretical Analysis of Pseudo-alive and Pseudo-dead Seedling

苗木假活、假死造成严重浪费。利用树木形态学、解剖学、生理学和土壤学基础知识分析苗木假活假死的本质。苗木成活是恢复重建末级根—叶片营养共同体,死亡则是由末端向基部的渐进式枯死过程。通过栈糖渠模型分析指出树木跨年度营养贮存是维持苗木活力的营养基础;利用形成层屏蔽假说揭示移植苗木成活的关键在于根尖分生能力的重建。进而揭示,苗木假活是残留根段吸收能力不足导致新梢枯死;假死则是断根愈伤并重建根尖分生能力的过程,宏观上表现为地上部分渐进式枯死。总之,根尖分生能力的恢复与重建是苗木假活、假死、枯死的关键。

The pseudo-alive and pseudo-dead seedling caused serious waste.Using the basic knowledge of tree morphology,anatomy,physiology and soil science to analyze the nature of pseudo-alive and pseudo-dead seedling.Seedling survival is the restoration and reconstruction of the final root-leaf nutritional community,while the death is a gradual process of dieback from the end to the base.Through the analysis of the‘sugar channel model’,which is pointed out that the cross-year nutrient storage of trees is the nutritional basis to maintain the vigor of seedlings.Using the‘cambium screening hypothesis’,it is suggested that the key to the survival of transplanted seedlings is the reconstruction of root apical meristem ability.Furthermore,it was revealed that the pseudo-alive seedling was caused by the lack of absorptive capacity of the residual root segment leading to the death of new shoots.While pseudo-dead is a process of callus and regeneration of root apical differentiation,which is manifested as gradual death of the aboveground part.In a word,the restoration and reconstruction of root tip differentiation ability is the key to pseudo-alive,pseudo-dead and dieback of seedlings.