Inheritance pattern of aluminum tolerance in pea

P>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 'Azad P1' and 'PC-55-11-1-2' were crossed with sensitive lines 'PC-493-5' and 'PSM-2'. 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.