Biochemical changes and protein profiling by sds-page of cajanus cajan during the early stages of seedling growth in response to cadmium stress

Pigeonpea is an important pulse crop in India. Seedlings of pigeonpea (Cajanus cajan L. Mill.) grown on treated with different cadmium (Cd) concentrations representing 0, 0.02, 0.04 and 0.06 mM were used in three pigeonpea cultivars, LRG30, LRG41 and ICPL85063 on protein, amino acid, free organic acids, proline and leaf storage protein profiles using SDS-PAGE were studied. Total protein content was exhibited higher levels in cv.LRG30 and lower levels of total free amino acid content when compared to LRG41 and ICPL85063 in response to Cd stress among the three pigeonpea cultivars. The changes in protein and amino acid contents in different organs of pigeonpea seedlings suggest that Cd affected the mobilization, hydrolysis and translocation of the storage substances to the growing axis from the cotyledons. The accumulation of free organic acids was relatively less in cv.LRG30 than in LRG41 and ICPL85063. The pigeonpea cultivars, LRG41 and ICPL85063 registered lower values of proline content when compared to LRG30 in response to Cd ions supplied indicating that LRG30 possesses better tolerance with more proline content. A change in leaf protein pattern was expressed differently among the three cultivars of pigeonpea. Among the three cultivars, LRG30 showed sharp and thick band pattern, where as thin and light coloured bands were observed in cv.LRG41 and ICPL85063 when compared to their controls.