环剥对火炬树克隆分株光合特性及生长状况的影响

以1a火炬树克隆分株为研究材料,采用人工环剥的方法(距地面10cm - 12cm,环剥宽度约为10cm)模拟平茬干扰处理,比较分析火炬树克隆分株的光合参数及形态生长指标的差异.结果表明:(1)环剥7d与同期对照相比,火炬树克隆分株的光合参数差异显著(P =0.042 ＜0.05),最大净光合速率下降68％,光补偿点升高129.8％,暗呼吸速率上升53.04％.(2)环剥处理7d,1a火炬树克隆分株的芽高、叶高分别降低50％和43.2％,前端水平侧根直径和后端水平侧根直径分别减少10.92％和7.96％.(3)环剥处理15d后,自环剥以上部位枝叶出现枯亡现象,而下部萌发新叶,1a火炬树克隆分株的净光合速率和表观量子效率等与同期对照相比,差异性不显著(P=0.498 ＞0.05),火炬树生理生长状况趋于正常.表明环剥对1a生火炬树克隆分株的抑制作用是暂时的.

EFFECT OF GIRDLING ON PHOTOSYNTHETIC CHARACTERISTICHS AND GROWTH CONDITION OF RHUS TYPHINA RAMETS

In order to analyze the effect of girdling on photosynthetic characteristics and growth condition of Rhus typhina ramets,we choosed 1 year Rhus typhina ramets as the material,adopt the method of girdling treatment by manpower(were girdled about10 cm wide at the position10-20 cm to base of tree),then analyze the changes of physiological indexes and morphological parameter.The experimental results showed that:1)At the beginning of girdling(7d),the maximum net photosynthetic rate of 1a Rhus typhina ramet compared with ck decreased by 68%;light compensation point and dark respiration rose by 129.8% and 53.04%;the significance of the photosynthetic parameters was Significant difference(P=0.042<0.05).2)After girdling treatment(7d),the width of the front and back part in the 1a clonal ramets decreased by 10.92% and 7.96%;the bud high、leaf high decreased by 50% and 43.2%.3)After 15 days later of girdling,at the top of 1a clonal ramets gradually died but the underpart germinated young leaves,the significance of the net photosynthetic rate and apparent quantum efficiency was inconspicuous compared with concurrent controls(P=0.498>0.05).Therefore,this paper shows that the effect of girdling on 1 year Rhus typhina L ramets were temporary.