Is magnesium deficiency the major cause of needle chlorosis of Pinus taeda in Brazil?

作     者：Ant?nio Carlos Vargas Motta Shizuo Maeda Valdécio dos Santos dos Santos Rodrigues Tamires Maiara Ercole Stephen Arthur Prior Ana Elisa Lyra Brumat Amanda Pacheco Cardoso Moura Julierme Zimmer Barbosa Jo?o Bosco Vasconcellos Gomes 

作者机构：Department of Soil Sciences and Agriculture EngineeringFederal University of Paraná Brazilian Agricultural Research Company Embrapa Florestas  3. United States Department of Agriculture-Agricultural Research Service USDA-ARS National Soil Dynamics Laboratory  4. Reforestation Remasa  5. Federal Institute of Southeast of Minas Gerais 

出 版 物：《Journal of Forestry Research》 (林业研究(英文))

年 卷 期：2024年第2期

页      面：213-225页

核心收录：

学科分类：0907[农学-林学] 08[工学] 0829[工学-林业工程] 09[农学] 

基　　金：supported by the National council for scientific and technological development (CNPq) and Higher Education Personnel Improvement Coordination (CAPES) 

摘      要：Needle chlorosis(NC) in Pinus taeda L. systems in Brazil becomes more frequent after second and third harvest rotation cycles. In a study to identify factors contributing to yellowing needle chorosis(YNC), trees were grown in soils originating from contrasting parent materials, and soils and needles(whole, green and chlorotic portions) from 1-and 2-year-old branches and the first and second needle flush release at four sites with YNC on P. taeda were analyzed for various elements and properties. All soils had very low base levels(Ca2+, Mg2+and K+) and P, suggesting a possible lack of multiple elements. YNC symptoms started at needle tips, then extended toward the needle base with time. First flush needles had longer portions with YNC than second flush needles did. Needles from the lower crown also had more symptoms along their length than those higher in the canopy. Symptoms were similar to those reported for Mg. In chlorotic portions, Mg and Ca concentrations were well below critical values; in particular, Mg levels were only one third of the critical value of 0.3 g kg-1. Collectively, results suggest that Mg deficiency is the primary reason for NC of P. taeda in various parent soils in Brazil.