基于叶片显微结构筛选耐盐碱苹果砧木

Screening of Salt-Alkali Tolerant Apple Rootstocks Based on Leaf Microstructure

从叶片解剖学角度分析不同苹果砧木品种的耐盐碱性,旨在筛选适宜新疆南疆盐碱土壤栽培的优良苹果砧木。本研究以7种四年生苹果砧木为试验材料,将NaCl、Na_(2)SO_(4)、NaHCO_(3)、Na_(2)CO_(3)按1:9:9:1的比例混合,盆栽浇灌1/2 Hoagland营养液,模拟浓度为60 mmol/L的盐碱复合胁迫,对照浇灌1/2 Hoagland营养液。通过光学显微镜观察14项叶片解剖结构,并结合主成分分析法和聚类系统法综合评价各砧木的耐盐碱性。研究发现盐碱复合胁迫对砧木叶片叶肉解剖结构产生的影响大于叶脉结构;盐碱复合胁迫后,耐盐碱性较强的砧木叶片的栅栏组织细胞、维管束结构和厚薄壁组织细胞变得发达,组织紧实度增大,而耐盐碱性较弱的砧木叶片的栅栏组织细胞短缩,海绵组织疏松,组织疏松度变大,主脉厚度减小。结果表明,7种供试材料的耐盐碱性分为三类,包括耐盐碱性强的八棱海棠,较强的小金海棠和平邑甜茶,较弱的野苹果、白海棠、山定子、湖北海棠。本研究结果为耐盐碱性强的苹果砧木选育提供一定的理论依据和参考价值。

The salt-alkali tolerance of different apple rootstocks was analyzed from the perspective of leaf anatomy in order to select the superior apple rootstocks suitable for salt-alkali soil cultivation in Southern Xinjiang.Us ing 7 four-year-old apple rootstocks as test materials,mix NaCl,Na_(2)SO_(4),NaHCO_(3),and Na_(2)CO_(3)at a ratio of 1:9:9:1,and water the pot with 1/2 Hoagland nutrient solution,with a simulated concentration of 60 mmol/L saline alkali compound stress,the control was poured 1/2 Hoagland nutrient solution.14 anatomical structures of leaves were observed by optical microscope,and the salt-alkali tolerance of each rootstock was evaluated by principal component analysis and clustering system method.The study found that the salt-alkali complex stress has greater influence on the anatomical structure of the leaf flesh of the rootstock than the vein structure.After salt-alkali complex stress,palisade tissue cells,vascular bundle structure and parenchyma tissue cells of strong salt-alkali tolerance rootstock leaves became developed and tissue compactness increased,while palisade tissue cells of weak salt-alkali tolerance rootstock leaves shortened,spongy tissue became loose,tissue looseness increased and main vein thickness decreased.The results showed that the salt-alkali tolerance of the 7 tested materials could be divided into three categories,including the strong salt-alkali tolerance of M.robusta,the stronger M.xiaojinensis and M.hupehensis var.pingyiensis,and the weaker M.sieversii,M.chaenomeles,M.baccata,M.hupehensis.The results of this study provide some theoretical basis and reference value for the breeding of apple rootstocks with strong salt-alkali tolerance.