栽植密度对枣园冠层结构与果实性状的影响

为探讨栽植密度对枣园冠层结构特征及果实性状的影响，以新疆阿克苏温宿县10 a生骏枣园为研究对象，利用LAI-2200植物冠层分析仪测定4种栽植密度(A.0.5 m×4.0 m、B.1.0 m×4.0 m、C.1.5 m×4.0 m、D.2.0 m×4.0 m)枣园叶面积指数(LAI)、平均叶倾角(MTA)、冠层开度(DIFN)与相对光合有效辐射(PAR)的物候变化，分析果实性状。结果表明，随着物候推进，枣园LAI和DIFN均呈现出先增大后减小的趋势，与不同物候期叶幕体积大小有关。随着株距不断增大，枣园LAI减小，树冠DIFN增大，相对PAR增强，光能利用率提高。C的单果重、可溶性糖含量、单株产量及每公顷产量均高于A和B,可滴定酸含量则明显低于A和B,糖酸比显著高于其他3种栽植密度。综合以上结果可知，1.5 m×4 m栽植密度能有效改善枣园冠层结构特征与光能利用效率，在稳定枣果产量的前提下提升了枣果品质。

Effects of Planting Density on Canopy Structure and Fruit Characters in Jujube Orchards

In order to explore the effects of planting density on canopy structure characteristics and fruit characters in jujube orchards,10-year-old jujube orchards (Ziziphus jujuba cv.Junzao) with four planting densities (A.0.5 m×4.0 m; B.1.0 m×4.0 m; C.1.5 m×4.0 m; D.2.0 m×4.0 m) were selected as the research objects in Wensu County,Aksu,Xinjiang.The phenological changes of leaf area index (LAI),mean tilt angle (MTA),canopy opening (DIFN) and relative photosynthetically active radiation (PAR) were measured with LAI-2200 plant canopy analyzer,and the fruit characters of jujube were investigated.The results showed that,with the advance of phenology,the LAI and DIFN all increased first and then decreased,which was related to the volume of leaf curtain in different phenological periods.With the increase of plant spacing,the LAI decreased,the DIFN increased,the relative PAR enhanced,and the light utilization efficiency increased.The single fruit weight,soluble sugar content,yield per plant and per hectare of C were higher than A and B,the titratable acid content was significantly lower than A and B,while the sugar-acid ratio was significantly higher than those of the other three planting densities.These results collectively suggested that the 1.5 m×4 m planting density could effectively improve the canopy structure characteristics and light utilization efficiency of jujube orchard,and improve the jujube fruit quality on the premise of stabilizing the yield.