追施钾肥对苹果叶片光合作用、矿质营养及果实品质的影响  

Effects of topdressing potassium fertilizer on photosynthesis,mineral nutrition of apple leaves and fruit quality

作　　者：张东东 李琪 储宝华 邹养军[1] ZHANG Dongdong;LI Qi;Chu Saohua;ZOU Yangjun(College of Horticulture,Northwest A&F University,Yangling,Shaanxi 712100,China)

机构地区：[1]西北农林科技大学园艺学院,陕西杨凌712100

出　　处：《西北农林科技大学学报（自然科学版）》2023年第4期102-109,共8页Journal of Northwest A&F University(Natural Science Edition)

基　　金：国家重点研发计划项目(2020YFD1000201)。

摘　　要：【目的】探究果实膨大期追施钾肥对苹果叶片光合作用、叶片和果实矿质元素含量及果实品质的影响,为合理施用钾肥提供理论依据。【方法】以陕西省洛川县10年生‘长富2号’苹果树作为试验材料,采用田间试验,研究不同钾肥(K_(2)O)追施量(0(CK),168(K_(1)),336(K_(2)),504(K_(3))和672(K_(4))kg/hm^(2))对新梢叶片的光合作用(净光合速率(Pn)、胞间CO_(2)浓度(C_(i))、气孔导度(G_(s))、蒸腾速率(T_(r))),新梢叶片及果实的矿质元素含量(N、P、K、Ca、Mg)以及果实品质(单果质量、果形指数、果实硬度、可滴定酸、可溶性固形物含量)的影响。【结果】与CK相比,果实膨大期追施钾肥可以显著提高新梢叶片的P_(n)、T_(r)以及G_(s),降低C_(i)。随着施钾量的增加,叶片的N、P、K含量均呈先增加后降低的趋势,在K_(3)处理达到最大值;叶片的Ca、Mg含量均呈先降低后增加的趋势,在K_(3)处理达到最低值。各处理苹果果实的矿质元素含量均表现为K>N>Ca>Mg>P,施钾处理的果实N、P和K含量均显著高于CK,以K_(3)处理最高;施钾处理果实的Ca、Mg含量均显著低于CK。与CK相比,施钾处理的果实可滴定酸含量显著降低,可溶性固形物含量显著提高(除K_(1)处理之外);施钾处理的果实单果质量增加,果形指数增大,果实硬度降低,但与CK差异均未达到显著水平。【结论】在果实膨大期追施钾肥,可以显著提高新梢叶片的光合作用,影响新梢叶片和果实的元素含量,改善果实的外观与内在品质,在本试验条件下推荐钾肥用量为504 kg/hm^(2),但追施钾肥的同时应增加钙肥的配施。【Objective】The effects of topdressing potassium fertilizer on photosynthesis,mineral element contents and fruit quality during fruit expansion period to provide basis for rational application of potassium fertilizer.【Method】A short field experiment was implemented in Luochuan,Shaanxi from June to November 2020 on 10-year-old Changfu-2 apple trees.Field experiments were conducted to study the effects of different potassium fertilizer topdressing rates(0(CK),168(K_(1)),336(K_(2)),504(K_(3))and 672(K_(4))kg/hm^(2))on photosynthesis of new shoot leaves(net photosynthetic rate P_(n),intercellular CO2 concentration Ci,stomatal conductance Gs and transpiration rate T_(r)),mineral elements of new shoot leaves and fruits(nitrogen N,phosphorus P,potassium K,calcium Ca and magnesium Mg)and fruit quality(single fruit quality,fruit shape index,fruit hardness,titratable acid and soluble solid contents).【Result】Topdressing potassium fertilizer at fruit expansion period significantly increased Pn,Tr and Gs of new shoots and leaves while reduced C_(i).With the increase of potassium application,contents of N,P and K in leaves increased first and then decreased with the maximum in K_(3) treatment.Contents of Ca and Mg in leaves decreased first and then increased with the lowest values in K_(3) treatment.The mineral elements of apple fruits were in the order of K>N>Ca>Mg>P.Contents of N,P and K in potassium treatment were significantly higher than CK,and K_(3) treatment had the highest values.Contents of Ca and Mg in fruits treated with potassium were significantly lower than those of CK.The titratable acid content of fruits treated with potassium decreased significantly,and soluble solid content increased significantly excepting K_(1) treatment.The single fruit quality and fruit shape index increased,while the fruit hardness decreased without significant differences.【Conclusion】Topdressing potassium fertilizer during the fruit expansion period could significantly improve photosynthesis of new shoot leaves,affect ele

关 键 词：苹果栽培 施钾量 光合作用 矿质元素 果实品质 

分 类 号：S661.1[农业科学—果树学]