不同生长势梨种质矮化预选指标的比较研究

Comparative Study on the Dwarfing Preselected Indices of Pear Germplasm with Different Growth Potential

[目的]为育种选择、选配亲本及性状的早期鉴定提供理论依据。[方法]以S2×山梨(乔化)、S2×山梨(矮化)、S2、山梨、极矮化种质为材料,从叶片气孔密度、枝皮率、叶片厚度、栅栏组织厚度、栅海比、导管密度等指标来判断各种质的矮化性状。[结果]5种梨种质中生长势强的山梨枝皮率、叶片厚度、栅栏组织厚度及栅海比最小,而气孔密度和导管密度最大。生长势弱的梨极矮化种质枝皮率、叶片厚度、栅栏组织厚度、栅海比最大,而气孔密度和导管密度最小。各种质在气孔密度、枝皮率、叶片厚度、栅栏组织厚度、栅海比、导管密度之间存在差异。[结论]气孔密度、枝皮率、叶片厚度、栅栏组织厚度、栅海比以及导管密度可作为梨树体生长势早期鉴定的指标。

[ Objective ] The aim was to provide a theoretical basis for breeding selection, matching parents and the identification of traits during early period. [Method] WithS2×Shanli （Pyros ussuriensis Maxim） （vigorous）, S2× Shanli （dwarfing）, S2,Shanli, super-dwarfing germplasm as the materials, the dwarfing traits of each germplasm were identified by indices including leaf stomata density, branch-cortex ratio, leaf thickness, palisade tissue thickness, palsade-spongy ratio and vessel density. [ Result] Among five kinds of pear germplasms, Shanli with strong growth potential had the smallest branch-cortex ratio, leaf thickness, palisade tissue thickness and palisade-spongy ratio, but the largest stomata density and vessel density. On the contrary, super-dwarfing germplasm with weak growth potential had the largest branch-cortex ratio, leaf thickness, palisade tissue thickness and palisade-spongy ratio, but the smallest stomata density and vessel density. There was a difference in stomata density, branch-cortex ratio, leaf thickness, palisade tissue thickness, palisade-spongy ratio and vessel density for every germplasm. [Conclusion ] Stomata density, branch-cortex ratio, leaf thickness, palisade tissue thickness, palisade-spongy ratio and vessel density can be used as indices of identification for pear growth potential in early period.