苹果幼树根际和根内细菌丰度及根际酶活性对土壤紧实胁迫的响应特征  

Response Characteristics of Rhizosphere and Root Endosphere Bacteria and Rhizosphere Enzyme Activities to Soil Compaction Stress in Young Apple Tree

作　　者：李佳琦 荀咪 石钧元 宋建飞 石宇佳 张玮玮[1] 杨洪强[1] LI JiaQi;XUN Mi;SHI JunYuan;SONG JianFei;SHI YuJia;ZHANG WeiWei;YANG HongQiang(College of Horticulture Science and Engineering,Shandong Agricultural University/State Key Laboratory of Crop Biology,Tai’an 271018,Shandong)

机构地区：[1]山东农业大学园艺科学与工程学院/作物生物学国家重点实验室,山东泰安271018

出　　处：《中国农业科学》2023年第13期2563-2573,共11页Scientia Agricultura Sinica

基　　金：国家自然科学基金(32172517);国家重点研发计划(2019YFD1000103)。

摘　　要：【目的】明确引起紧实胁迫下苹果根系微域环境中细菌丰度变化的主要因子,揭示土壤胁迫下苹果根际生物学特征,为果园土壤管理提供参考。【方法】以砧木分别为平邑甜茶(Malus hupehensis Rehd.)和八棱海棠(Malus robusta Rehd.)的2年生‘红富士’苹果(Malus domestica Borkh.cv.Red Fuji)盆栽幼树为试材,通过镇压土壤设置紧实胁迫,检测根际矿质养分含量和土壤酶活性以及根际细菌和根系内生细菌丰度。【结果】无论是红富士/平邑甜茶还是红富士/八棱海棠,土壤紧实胁迫均明显提高苹果根际速效磷和有效钾含量,提高根际过氧化氢酶活性;显著降低根际碱解氮含量和根际蔗糖酶、脲酶、酸性磷酸酶活性,以及根系内生细菌的丰度,并改变根际微生物组成结构。土壤紧实胁迫下,根际细菌数量和丰度、根际荧光素二乙酸酯(fluorescein diacetate,FDA)水解酶活性的变化因砧木而不同,它们在红富士/平邑甜茶中显著降低,降低幅度分别为46.88%、50.50%和29.13%;在红富士/八棱海棠中则显著升高,升高幅度分别为51.41%、20.22%和13.76%。土壤紧实胁迫下,红富士/平邑甜茶根际碱解氮含量、水解酶(蔗糖酶、脲酶、酸性磷酸酶)活性以及根内细菌丰度的下降幅度大于红富士/八棱海棠;红富士/八棱海棠根际比红富士/平邑甜茶具有更强的FDA水解酶活性。冗余分析显示,土壤紧实胁迫下,根际有效钾、碱解氮和FDA水解酶活性对苹果根际和根内细菌丰度变异的解释率最高。【结论】土壤紧实胁迫显著影响苹果根际微生物组成,进而改变根际土壤酶活性和根际有效性矿质养分的含量。根际细菌和FDA水解酶活性的变化因砧木而不同,其在红富士/平邑甜茶中受到土壤紧实胁迫的抑制程度较高。土壤紧实胁迫下,苹果根际有效钾和碱解氮磷含量以及FAD水解酶酶活性的改变与根际和根内细菌丰度的变化存在更密切【Objective】The aim of this study was to identify the main factors causing bacterial abundance changed in the apple roots microenvironment under compaction stress,so as to provide a reference for further revealing the biological characteristics of apple rhizosphere and orchard soil management under soil stress.【Method】The experimental materials were potted young apple(Malus domestica Borkh.cv.Red Fuji)tree with the rootstocks of Malus hupehensis Rehd.and Malus robusta Rehd.,respectively.After pressing the potted soil to form compaction stress, the rhizosphere mineral nutrient content, soil enzyme activity and the bacterial abundance of rhizosphere and root endosphere were measured.【Result】In both M. huphensis and M. robusta, the soil compaction stress significantly increased rhizosphere available phosphorus content, available potassium content and catalase activity, however, significantly decreased rhizosphere alkaline-hydrolyzed nitrogen content, sucrase activity, urease activity, acid phosphatase activity and root endosphere bacterial abundance. Furthermore, the soil compaction stress also changed the composition and structure of rhizosphere microorganisms. Under soil compaction stress, the amount and abundance of rhizosphere bacterial and the activity of fluorescein diacetate (FDA) hydrolase changed with different rootstocks;however, which were significantly decreased in Red Fuji/M. hupehensis, with the reduction rates were 46.88%, 50.50% and 29.13%, respectively, and significantly increased in Red Fuji/M. robusta, with the increases were 51.41%, 20.22% and 13.76%, respectively. In compacted soil, rhizosphere alkali- hydrolyzed nitrogen content, hydrolase (sucrase, urease, acid phosphatase) activities and the bacterial abundance of root endosphere in Red Fuji/M. hupehensis decreased more than that in Red Fuji/M. robusta. Compared with Red Fuji/M. hupehensis, Red Fuji/M. robusta had stronger FDA hydrolase activity and recruited more rhizosphere bacteria. Redundancy analysis showed that rhizosphere av

关 键 词：土壤紧实 苹果砧木 根际 土壤酶 根内生细菌 

分 类 号：S661.1[农业科学—果树学]