Conductivity of the phloem in mango (Mangifera indica L.)  

作　　者：Miguel Barcelo-Anguiano Jose I.Hormaza Juan M.Losada 

机构地区：[1]Instituto de Hortofruticultura Subtropical y Mediterranea La Mayora(IHSM La Mayora-CSIC-UMA),Avda Dr.Wienberg s/n.29750,Algarrobo-Costa,Malaga,Spain

出　　处：《Horticulture Research》2021年第1期2045-2053,共9页园艺研究（英文）

基　　金：J.I.H.was supported by the‘Ministerio de Ciencia e Innovacion’-European Regional Development Fund,European Union(PID-2019-109566RB-100);Junta de Andalucia(P18-RT-3272).

摘　　要：Mango(Mangifera indica L.,Anacardiaceae),the fifth most consumed fruit worldwide,is one of the most important fruit crops in tropical regions,but its vascular anatomy is quite unexplored.Previous studies examined the xylem structure in the stems of mango,but the anatomy of the phloem has remained elusive,leaving the long-distance transport of photoassimilates understudied.We combined fluorescence and electron microscopy to evaluate the structure of the phloem tissue in the tapering branches of mango trees,and used this information to describe the hydraulic conductivity of its sieve tube elements following current models of fluid transport in trees.We revealed that the anatomy of the phloem changes from current year branches,where it was protected by pericyclic fibres,to older ones,where the lack of fibres was concomitant with laticiferous canals embedded in the phloem tissue.Callose was present in the sieve plates,but also in the walls of the phloem sieve cells,making them discernible from other phloem cells.A scaling geometry of the sieve tube elements-including the number of sieve areas and the pore size across tapering branches-resulted in an exponential conductivity towards the base of the tree.These evaluations in mangofit with previous measurements of the phloem architecture in the stems of forest trees,suggesting that,despite agronomic management,the phloem sieve cells scale with the tapering branches.The pipe model theory applied to the continuous tubing system of the phloem appears as a good approach to understand the hydraulic transport of photoassimilates in fruit trees.

关 键 词：transport ANATOMY walls 

分 类 号：S667.7[农业科学—果树学]