Genetic control of aluminium tolerance in pigeonpea (Cajanus cajan L.)

Aluminium toxicity is a major factor limiting plant growth in acid soil and more adequate genetic tolerance is needed to improve pigeonpea adaptation and production in affected areas. To study the inheritance, tolerant lines IPA7-10, T-7 were crossed with sensitive lines Pusa 9 and Bahar. The parents, F1, F2 and F3 generations were grown in a nutrient solution containing 30 ppm aluminium for hematoxylin staining and root re-growth measure and classified for tolerance by staining of root tips and root re-growth. The segregation ratios obtained for aluminium tolerance in the F2 and F3 generations were 15 : 1 and 7 : 8 : 1, respectively. These results indicated that aluminium tolerance is controlled by two dominant genes.