biologia plantarum

Biologia plantarum 59:83-91, 2015 | DOI: 10.1007/s10535-014-0474-x

Marker-assisted breeding for TaALMT1, a major gene conferring aluminium tolerance to wheat

B. J. Soto-Cerda^1,2, C. Inostroza-Blancheteau^2,3, M. Mathías⁴, E. Peñaloza⁵, J. Zuñiga⁴, G. Muñoz⁶, Z. Rengel⁷, H. Salvo-Garrido^1,4,*

¹ Agriaquaculture Nutritional Genomic Center CGNA, Genomics and Bioinformatics Unit, Temuco, Chile

² Núcleo de Investigación en Producción Alimentaría, Facultad de Recursos Naturales, Temuco, Chile

³ Escuela de Agronomía, Universidad Católica de Temuco, Temuco, Chile

⁴ Centro Regional de Investigación Carillanca, INIA, Temuco, Chile

⁵ Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile

⁶ Facultad de Ciencias Biológicas, Universidad Andrés Bello, Talcahuano, Chile

⁷ School of Earth and Environment, University of Western Australia, Crawley, Australia

Aluminium toxicity in acid soils is the main limitation to crop production worldwide. In wheat (Triticum aestivum L.), the Al-activated malate transporter (TaALMT1) gene located on chromosome 4DL is associated with malate efflux and Al-tolerance. To introgress Al-tolerance from the breeding line CAR3911 into the high yielding Al-sensitive cultivar Kumpa-INIA, phenotypic and molecular characterizations of gene/QTL underlying Al-tolerance in CAR3911 followed by marker-assisted backcrossing (MAS-BC) were undertaken. Al-tolerant backcross (BC) lines were selected using the functional marker ALMT1-4 designed immediately upstream of the TaALMT1 coding region. Foreground and background selections using ALMT1-4 and microsatellite markers were conducted. Linkage and sequence analyses suggest that the TaALMT1 gene could underly the Al-tolerance in CAR3911, possessing the same promoter type (V) as the Al-tolerant genotypes Carazinho and ET8. The MAS-BC strategy allowed the selection of Al-tolerant lines with the smallest introgressed region (6 cM) on 4D and the highest recurrent parent genome (RPG) (98 %) covering 2 194 cM of the wheat genome. The homozygous BC3F2 line named Kumpa-INIA-TaALMT1 expressed a 3-fold higher Al-tolerance than its isogenic line Kumpa-INIA at 40 μM Al in the hydroponic solution, and similarly to CAR3911 and Carazinho. The MAS-BC strategy was successful for the introgression of the TaALMT1 gene into Kumpa-INIA in only three BC generations, shortening the breeding cycle to 24 months, which promises to increase wheat production and a greater yield stability in the acid soils of Southern Chile.

Keywords: acid soils; backcross lines; gene expression; introgression; malate transporter; microsatellite markers

Subjects: marker-assisted selection; aluminum; gene expression; microsatellite markers; malate transporter; linkage mapping; wheat

Received: February 13, 2014; Revised: April 16, 2014; Accepted: August 18, 2014; Published: January 1, 2015  Show citation