部分根域施有机肥对梨幼树生长与生理特性的影响

Changes of growth and physiological characteristics of young pear trees with partial root-zone applied organic manure

【目的】探讨梨园有机肥施用方法与合理的施肥量。【方法】以3 a生分根盆栽梨幼树为材料,研究砂土、壤土2/4根域用10%、20%、30%有机肥改良对新梢生长和枝类组成等生长指标,叶片水势、净光合速率、蒸腾速率和气孔导度等生理指标的影响。【结果】砂土、壤土2/4根域改良均显著促进梨幼树新梢生长,调控长、中、短枝数量和枝类组成。其中,随有机肥水平增加,砂土栽培梨幼树新梢生长量与总枝量等先增加后降低;壤土栽培时则逐渐降低,且砂土、壤土分别以20%、10%有机肥处理最大。2/4根域施用有机肥能有效调控梨幼树叶片水势、净光合速率、蒸腾速率和气孔导度等生理指标。砂土上10%有机肥处理,有机肥施用量不足,对叶片生理特性指标的促进作用较小;砂土栽培30%有机肥及壤土栽培20%、30%有机肥处理,有机肥施用量偏高,对梨幼树叶片生理特性有抑制效应。【结论】从促进梨幼树树体生长和叶片生理特性指标考虑,2/4根域改良条件下,砂土施用20%有机肥、壤土施用10%有机肥的效果最好。

【Objective】The objective of this study is to explore the method of fertilization and quantity for organic manure in pear orchard.【Methods】Two-year-old pear trees potted in sandy and loam soil were used as materials to investigate the changes of growth and physiological characteristics including growth and type of new shoots,leaf water potential,net photosynthetic rate（Pn）,transpiration rate（Tr） and stomatal conductance（Gs） after the fertilization of 10%,20% and 30% organic manure only in 2/4 root-zone.【Results】The results indicated that the growth of new shoots as well as the number of long,medium and short shoots and the type of new shoots increased significantly when 2/4 root-zone was improved by organic manure. The shoot growth rate and total number of shoots increased first and then decreased with the increase of organic manure in sandy soil. However,those declined gradually in loam soil. The treatment of 20% and 10% organic manure obtained the largest growth rate in sandy and loam soil,respectively. Leaf physiological characteristics such as water potential,Pn,Tr and Gs were also regulated by organic manure. The leaf physiological characteristics did not changed much with 2/4 root-zone improved by 10% organic manure. However,the higher levels of organic manure application,such as 30% organic manure insandy soil or 20%,30% in loam soil in hibited physiological characteristics to some degree.【Conclusion】Considering the growth and leaf physiological characteristics,20% organic manure in sandy soil and 10%in loam soil are the optimal treatments.