Inheritance of aluminum tolerance in maize

Abstract

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Selection of maize hybrids for tolerance to aluminum in minimal solution

“…After 10 days of exposure, marked differences in root growth were observed between tolerant and sensitive strains. Boni et al (2009) subsequently confirmed the phenotypic differences in Al tolerance between the parental lines at this same concentration.…”

“…Discrepancies found in the literature regarding the most appropriate concentration of Al for identifying sources of Al tolerance in cereal crops may be linked to the genetic basis of the tested genotypes, composition of the nutrient solution, and exposure time and pH of the solution. Several authors have used concentrations of 4.5 mg/L Al (Machado and Pereira, 1990;Paterniani and Furlani, 2002;Prioli et al, 2002;Boni et al, 2009) or 6 mg/L Al (Martins et al, 1999;Sibov et al, 1999;Mazzocato et al, 2002) for this purpose. Other studies, based on complete nutrient solution, adjusted the activity (effective concentration) of Al (27-50 mM) based on the genotypes assessed (Doncheva et al, 2005;Piñeros et al, 2005;Caniato et al, 2007;Maron et al, 2008Maron et al, , 2010.…”

Genetic control of aluminum tolerance in tropical maize germplasm

“…Th ese authors concluded that the high Al tolerance of Cateto maize are conditioned mainly by additive eff ects genes, which are concentrated, probably, on the origin variety, considering that the cultivation of this maize was done by indigenous and ancient farmers, in areas of soil with high Al content. Th e results obtained by Sawazaki and Furlani (1987) corroborate with the hypothesis that the Cateto maize race, of ancient origin, is considered an important Al tolerant source (Prioli and Silva 1984;Sibov et al 1999;Boni et al 2009). According Prioli and Silva (1984), the tolerant lines are in the most of fl int endosperm, originated from Cateto race, while the most sensitive, are dent, type Tuxpeño.…”

“…Possibly, the absence of perfect symmetry in the frequency distribution graphs could be associated to the environmental effect on tolerance expression of the individuals, the possibility of evaluators' errors in phenotyping, size of the F 2 populations evaluated, and in some families the presence of the dominance effect of Al tolerance. Prioli et al (2000) and Boni et al (2009) reported a pattern of bimodal frequency distribution for the F 2 generation individuals from the cross of contrasting lines for tolerance. The authors emphasize that this type of distribution is an indicative of monogenic inheritance with complete dominance to Al tolerance.…”

“…The great divergence of results for Al tolerance in maize may be correlated to the type of germplasm used and the different genotypic constitutions, which can generate conflicting phenotypic expressions (Boni et al 2009). Therefore, further scientific studies are required on the genetic inheritance involved in Al tolerance in maize.…”