栽植密度对柑桔树光合生产、生长和结实的影响

Effect of Planting Density on Photosynthetic Production,Growth and Fruit-Bearing of a Citrus Tree

栽植密度显著影响柑桔树冠内的光能分布和利用水平,制约树冠叶群的光合生产能力,从而进一步影响树体的生长发育状况,以及营养生长和生殖生长水平,最终表现出果实产量和品质的差异。枳砧温州蜜柑实行合理密植栽培的行距宜控制在3～4m,株距2m左右,当树冠内相对光照水平下降到40%时,必须加强整枝修剪或及时间移。

In this study,it was found that distribution and utilization of photosynthetically active radition (PAR) in citrus canopy were remarkably affected by its planting density,which had further influenees on development of the tree,its vegetative and reproductive growth, and finally the fruit yield and quality. According to the results, the optimum distance for rational dense planting of Citrus unshiu on Poncitrus trifoliata should be 4～3m×2m,with a planting density of 1250～1667 trees per hm^2. Suitable indices of the tree canopy at mature age should be controlled as follows:trunk height 0.2～0.3m,canopy height 2.1～2.5m,mean of canopy thickness 1.4～1.6m,and mean of leaf area index(LAI)in the canopy 5.5～6.5. When LAI was above 6.5,and relative PAR in the canopy was as low as 40%,a series of measure should be adopted in training and pruning of the canopy as well as in removing some trees as to control the optimum LAI. Only by this way, can high yield and superior quality of citrus fruits be attained year by year.