摘要
以苹果砧木G935幼苗为试材,采用13C同位素示踪技术,以适宜供钾(6 mmol·L^(-1))为对照,水培条件下研究了高钾(18 mmol·L^(-1))下不同镁水平(0.1、3、6 mmol·L^(-1))对苹果生长和光合碳代谢的影响。结果表明:与适宜供钾相比,高钾处理显著降低了叶片净光合速率和碳代谢酶活性,抑制了光合产物向根系的分配,最终抑制了植株生长。而添加镁缓解了高钾对苹果植株生长的抑制,3和6 mmol·L^(-1)Mg处理下苹果幼苗生物重分别比0.1 mmol·L^(-1)Mg处理提高55.69%和66.45%。高钾条件下添加镁显著提高了苹果幼苗的Pn、Gs、光能捕获能力和光合电子传递能力,与0.1 mmol·L^(-1)Mg处理相比,6 mmol·L^(-1)Mg处理的Pn、Gs、PSⅡ最大光化学效率(Fv/Fm)和PSⅡ实际光化学效率(ΦPSⅡ)分别提高204%、159%、12.67%和36.44%。高钾条件下,随着供镁水平的增加,6-磷酸山梨醇脱氢酶(S6PDH)、蔗糖合成酶(SS)和蔗糖磷酸合成酶(SPS)活性逐渐上升,13C积累量也随供镁水平的提高而增加;而且镁还显著促进了叶片13C光合产物向根系的运输。综上,高钾条件下供镁提高了叶片净光合速率,增加了光合产物的积累量,并促进了光合产物向根系的分配,为根的生长发育提供了充足的能量和碳骨架,最终缓解了高钾对苹果植株生长的抑制。
This experiment was carried out to study the effects of different magnesium levels(0.1,3,and 6 mmol·L^(-1))on apple dwarfing rootstock G935 seedlings growth and photosynthetic carbon metabolism under suitable(6 mmol·L^(-1))and high potassium(18 mmol·L^(-1))conditions,using 13C isotopic tracer technology,and conducted under hydroponic conditions.The results showed that high K treatment significantly reduced the net photosynthetic rate of leaves and carbon metabolic enzyme activity,inhibited the allocation of photosynthetic products to the root system,and inhibited plant growth compared to suitable K treatment.In contrast,adding Mg alleviated the inhibition of high K on apple plant growth,compared to the K18Mg0.1 treatment,the apple seedlings'biomass weight increased by 55.69%and 66.45%under the K18Mg3 and K18Mg6 treatments,respectively.Under high K conditions,Mg significantly increased Pn,Gs,the light energy capture ability and photosynthetic electron transport capacity.Compared to the K18Mg0.1 treatment,Pn,Gs,Fv/Fm andΦPSⅡin the K18Mg6 treatment increased by 204%,159%,12.67%and 36.44%,respectively.Under high K conditions,as the Mg supply level increases,the activities of 6-phosphoribosyl dehydrogenase(S6PDH),sucrose synthase(SS),and sucrose phosphate synthase(SPS)gradually increased,the accumulation of 13C also intensified with the boost in magnesium supply level,and magnesium significantly promoted the transportation of 13C photosynthetic products from leaves to roots In summary,providing magnesium under high potassium conditions enhances the net photosynthetic rate of leaves,increases the accumulation of photosynthetic products,and facilitates the distribution of photosynthetic products to roots.This ensures an adequate supply of energy and carbon skeletons for root growth and development,ultimately alleviating the growth inhibition imposed by high potassium on apple plants.
作者
覃寒晗
汪秋依
倪伟
谢洪梅
关亚菲
朱占玲
葛顺峰
姜远茂
QIN Hanhan;WANG Qiuyi;NI Wei;XIE Hongmei;GUAN Yafei;ZHU Zhanling;GE Shunfeng;JIANG Yuanmao(College of Horticulture Science and Engineering,Shandong Agricultural University,Apple Technology Innovation Center of Shandong Province,Collaborative Innovation Center of Fruit&Vegetable Quality and Efficient Production of Shandong Province,Taian,Shandong 271018,China)
出处
《植物生理学报》
CAS
CSCD
北大核心
2024年第6期998-1006,共9页
Plant Physiology Journal
基金
国家重点研发计划项目(2023YFD2301000)
国家现代农业产业技术体系建设资金项目(CARS–27)
山东省自然科学基金项目(ZR2021MC093)。
关键词
苹果
钾
镁
光合
碳代谢
13C
apple
potassium
magnesium
photosynthetic
carbon metabolism
13C
