不同基质对苹果幼树生长发育及叶片生理特性的影响

本研究旨在筛选出适合苹果幼树栽培的基质配方。以2 年生富士芽苗为试材，采用玉米秸杆、园土、草炭土、珍珠岩和牛粪为基质原料，研究不同基质配方对苹果幼树的生长、生物量、根系形态特性和叶片生理特性等参数的影响。研究结果表明：T3（园土:草炭土:牛粪:珍珠岩=2:3:1:1）和T4（园土:玉米秸秆:牛粪:珍珠岩=2:3:1:1）基质最佳，其理化性质理想，栽培的苹果幼树生长量（苗高、茎粗、新梢长、新梢粗、地上部干物质重）、根系发育情况（根系总长、根表面积、根体积、根尖数）和叶片生理特性（净光合速率、蒸腾速率、气孔导度和胞间CO2浓度）等指标都显著高于对照，根冠比和根平均直径则显著低于对照。因此，腐熟后的玉米秸杆完全可代替草炭土在苹果幼树容器栽培中使用，T4 基质可作为培育苹果容器大苗的优良基质在生产上推广应用。

Effects of Substrates on Growth and Leaf Physiological Characteristics of Young Apple Trees

This study aims to screen out the suitable substrate formulations for cultivating young apple trees. Taking 2-year-old Fuji bud seedlings as test materials, and corn straws, orchard soil, peat soil, perlite and cow dung as substrate materials, effects of different substrate formulations on the growth, biomass, root morphological characteristics and leaf physiological characteristics of young apple trees were studied. Results showed that T3 (orchard soil: peat soil: cow dung: perlite=2:3:1:1) and T4 (orchard soil: corn straw: cow dung: perlite=2:3:1:1) were the optimal substrates with ideally physical and chemical properties, the indexes including growth of young apple trees (seedling height, stem diameter, shoot length, shoot diameter, dry matter weight above ground), root development (total root length, root surface area, root volume, number of tips) and physiological characteristics of leaves (net photosynthetic rate , transpiration rate, stomatal conductance and intercellular CO2 concentration) were all higher than those of the control, while the root-shoot ratio and the average diameter of root was significantly lower than those of the control. Therefore, thoroughly decomposed corn straws could completely replace peat soil in the application of container cultivation of young apple trees, and T4 substrate could be promoted as an excellent matrix for cultivation of big apple seedlings in containers.