Back to Acid Soil Fields: The Citrate Transporter SbMATE Is a Major Asset for Sustainable Grain Yield for Sorghum Cultivated on Acid Soils.
Aluminum (Al) toxicity damages plant roots and limits crop production on acid soils, which comprise up to 50% of the world's arable lands. A major Al tolerance locus on chromosome 3, AltSB, controls aluminum tolerance in sorghum [Sorghum bicolor (L.) Moench] via SbMATE, an Al-activated plasma membrane transporter that mediates Al exclusion from sensitive regions in the root apex. As is the case with other known Al tolerance genes, SbMATE was cloned based on studies conducted under controlled environmental conditions, in nutrient solution. Therefore, its impact on grain yield on acid soils remains undetermined. To determine the real world impact of SbMATE, multi-trait quantitative trait loci (QTL) mapping in hydroponics, and, in the field, revealed a large-effect QTL colocalized with the Al tolerance locus AltSB, where SbMATE lies, conferring a 0.6 ton ha(-1) grain yield increase on acid soils. A second QTL for Al tolerance in hydroponics, where the positive allele was also donated by the Al tolerant parent, SC283, was found on chromosome 9, indicating the presence of distinct Al tolerance genes in the sorghum genome, or genes acting in the SbMATE pathway leading to Al-activated citrate release. There was no yield penalty for AltSB, consistent with the highly localized Al regulated SbMATE expression in the root tip, and Al-dependent transport activity. A female effect of 0.5 ton ha(-1) independently demonstrated the effectiveness of AltSB in hybrids. Al tolerance conferred by AltSB is thus an indispensable asset for sorghum production and food security on acid soils, many of which are located in developing countries.
['Carvalho|Geraldo|G|', 'Schaffert|Robert Eugene|RE|', 'Malosetti|Marcos|M|', 'Viana|Joao Herbert Moreira|JH|', 'Menezes|Cicero Bezerra|CB|', 'Silva|Lidianne Assis|LA|', 'Guimaraes|Claudia Teixeira|CT|', 'Coelho|Antonio Marcos|AM|', 'Kochian|Leon V|LV|', 'van Eeuwijk|Fred A|FA|', 'Magalhaes|Jurandir Vieira|JV|']
D000535:Aluminum D002352:Carrier Proteins D002523:Edible Grain D008040:Genetic Linkage D005819:Genetic Markers D007178:Inbreeding D010641:Phenotype D040641:Quantitative Trait Loci D019655:Quantitative Trait, Heritable D055049:Salt Tolerance D012987:Soil D045868:Sorghum
Al tolerance AltSB Sorghum bicolor QTL mapping field trials