育苗容器对紫叶紫薇容器苗生长、开花及生理的影响

Effects of seedling containers on the growth,flowering,and physiology of purple-leaf Lagerstroemia indica seedlings

【目的】探讨育苗容器类型和规格对紫叶紫薇容器苗生长、开花及生理的影响,筛选出培育紫叶紫薇容器苗的适宜育苗容器,为高效培育紫薇容器苗提供理论依据。【方法】以紫叶紫薇优良新品种‘丹红紫叶’2年生苗木为研究材料,选用黑色塑料营养杯(C1)、白色无纺布美植袋(C2)、黑色控根容器(C3)3个类型以及16×16(D1)、21×21(D2)、25×25(D3)3种规格(直径×高,cm),组成9种容器组合处理,测定不同处理容器苗生长、开花及生理指标。【结果】(1)不同育苗容器处理对紫叶紫薇容器苗的生长、开花及生理指标均影响显著,同一容器类型苗木的生长、根系、生物量、花期、花径、花序、可溶性蛋白含量、可溶性糖含量、相对叶绿素含量、净光合速率、气孔导度、蒸腾速率等指标均随着育苗容器规格的增大而显著增加。(2)地径生长量、总根长、总根表面积、总根体积、根尖数、地上部干质量、地下部干质量、总干质量、花期均以C3D3处理最大,比最小的C1D1处理分别显著提高817.12%、108.12%、94.60%、75.66%、144.14%、135.67%、228.45%、164.65%、34.48%;苗高生长量、冠幅生长量、叶面积、花序长和宽均以C1D3处理最高,比最低的C1D1处理分别显著提高116.05%、81.39%、114.95%、70.44%和65.79%;相对叶绿素含量、水分利用效率均以C3D3处理最大,可溶性蛋白和可溶性糖含量、净光合速率、气孔导度均以C1D3处理最高;胞间CO_(2)浓度、水分利用效率在各处理之间无显著差异。(3)各处理隶属函数法综合评价得分排序为:C3D3>C1D3>C2D3>C3D2>C2D2>C1D2>C2D1>C3D1>C1D1。【结论】黑色控根容器在地径生长量、根系生长指标、生物量、花期和花径、叶绿素相对含量及净光合速率方面表现最佳;紫叶紫薇2年生苗的最适宜育苗容器是直径25 cm、高25 cm的黑色控根容器。

[Objective]This study aims to examine the effects of container type and specification on the growth,blooming,and physiology of purple-leaf Lagerstroemia indica seedlings.The goal is to examine the optimal seedling container for the cultivation of purple-leaf L.indica seedlings and to provide basis for effective seedling breeding in containers.[Methods]Taking the excellent new variety‘Ebony Embers’of purple-leaf L.indica as research materials.Three type containers,black plastic nutrient cups(C1),white nonwoven beauty planting bags(C2),and black root-control containers(C3),with three specifications(diameter×height,cm)of 16×16(D1),21×21(D2),and 25×25(D3),were selected to set nine treatments.Seedlings under different treatments were measured for growth,flowering,and physiological indexes.[Results](1)Different nursery containers had significant effects on the growth,flowering,and physiology of purple-leaf L.indica seedlings.The growth,root system,biomass,flowering period,flower diameter,inflorescence,soluble protein content,soluble sugar content,relative chlorophyll content,net photosynthesis rate,stomatal conductance,transpiration rate,and other indexes in the same container type were increased with the increase in the specification of the containers.(2)Diameter growth,total root length,total root surface area,total root volume,number of root tips,aboveground dry mass,belowground dry mass,total dry mass,and flowering time were greatest in the C3D3 treatment,which was higher than the smallest C1D1 treatment by 817.12%,108.12%,94.60%,75.66%,144.14%,135.67%,228.45%,164.65%and 34.48%,respectively.Seedling height growth,crown growth,leaf area,and inflorescence length and width were the highest in the C1D3 treatment,which was higher than the lowest C1D1 treatment by 116.05%,81.39%,114.95%,70.44%,and 65.79%,respectively.Relative chlorophyll content and water use efficiency were the greatest in the C3D3 treatment,while soluble protein and soluble sugar content,net photosynthetic rate,and stomatal conductance were the highest in the C1D3 treatment.The intercellular CO_(2) concentration and water use efficiency did not differ significantly among the treatments.(3)The comprehensive analysis score for each index was as follows:C3D3>C1D3>C2D3>C3D2>C2D2>C1D2>C2D1>C3D1>C1D1.[Conclusion]The black root-control container performs well in terms of diameter growth,root growth index,biomass,flowering time and diameter,relative chlorophyll content,and net photosynthetic rate.The most suitable container for 2-year-old seedlings of purple-leaf L.indica is the black root-control container with a diameter of 25 cm and a height of 25 cm.