Inheritance pattern of aluminum tolerance in pea

Abstract

An understanding of the inheritance of aluminum (Al) tolerance is important to breed for Al tolerant genotypes of pea (Pisum sativum L.). Therefore, an investigation was undertaken to infer genes governing Al tolerance in pea. To study the inheritance of Al tolerance, tolerant lines ÔAzad P1Õ and ÔPC-55-11-1-2Õ were crossed with sensitive lines ÔPC-493-5Õ and ÔPSM-2Õ. Parental, F 1 , F 2 and backcross generations were grown in a nutrient solution containing 30 ppm of Al for haematoxylin staining and root regrowth and classified for tolerance by staining of root tips and root regrowth. The F 1 hybrids responded similarly to the tolerant parents indicating dominance of Al tolerance over sensitivity. Segregation for tolerance vs. sensitivity in F 2 fitted well with the 3 : 1 ratio expected for a single gene. The backcrosses involving dominant parents showed the dominant reaction on all the plants while those involving susceptible parents segregated into one tolerant to one sensitive ratio. Experimental results showed that Al tolerance is a monogenic dominant trait that can be easily transferred to desirable lines through backcross breeding programme.

Screening of pigeonpea genotypes for nutrient uptake efficiency under aluminium toxicity

“…Root re-growth virtually ceased in Bahar, Pusa 2002-2 and Pusa 9 at higher Al concentrations (123 or 205 μM Al) due to irreversible damage caused to the root tips. For efficient discrimination among genotypes against Al toxicity through root regrowth assay, 123 μM Al level was found optimum as has also been observed in other crops (Echart et al 2002;Nava et al 2006;Singh and Choudhary 2010). The variable response of pigeonpea genotypes to Al toxicity was most likely due to difference in genetic potential of pigeonpea genotypes.…”

“…However, breeding for aluminium tolerance requires a rapid and effective technique to discriminate between tolerant and sensitive genotypes. The two most commonly used techniques are hematoxylin staining and root re-growth assay (Singh and Choudhary 2010). These two techniques have unconditional advantages over field screening because reliable ranking of tolerance in the field screening is difficult due to the large temporal and spatial variation in acidic soils.…”

“…Most of the grain legumes including chickpea (Singh and Chaturvedi 2007), pigeonpea (Singh and Choudhary 2009), pea (Singh and Choudhary 2010) and alfalfa (Campbell et al 1988) are sensitive to aluminium. Considerable variation for tolerance to aluminium toxicity in plant species and genotypes within species has been reported (Kinraide et al 1985;Singh and Choudhary 2009).…”

Variation of aluminium tolerance in lentil (Lens culinaris Medik.)

“…2008). Inhibition of root elongation has been widely recognized as a trait for the screening of aluminium (Al) stress (Delhaize and Ryan 1995, Gallego and Benito 1997) and is mostly used in genetic studies (Singh and Choudhary 2010, Singh and Raje 2011a, Khatiwada et al. 1996).…”

“…The haematoxylin staining and root regrowth are frequently used techniques because they have produced consistent results (Singh et al. 2009, Singh and Choudhary 2010, Singh and Raje 2011a, Singh et al. 2011c, Singh 2012).…”