Anatomic features, tolerance index, secondary metabolites and protein content of chickpea (Cicer arietinum) seedlings under cadmium induction and identification of PCS and FC genes.

ABSTRACT

ABSTRACT Chickpea (Cicer arietinum) belonging to the Fabaceae family is a major legume crop and is a good source of protein and carbohydrates. Industrialization has resulted in soil contamination with heavy metals such as cadmium. Adsorption of cadmium by plants can lead to reduced yields and heavy metal toxicity. In the current study, changes in the anatomical, morphological features and biochemical properties of the chickpea plant were evaluated. Two indexes DWSTI and PHSTI were determined. Anatomically, there was a change in the number of xylem poles within the root structure which was most significant at treatments of 125 µg cadmium. There was also a noticeable change in leaf pigmentation, the total phenolics and soluble protein in the plant. Cadmium levels were elevated attaining concentrations of 0.21, 0.40 and 0.52 mg per gram dry weight in plants exposed to 62, 125 and 250 µg/g Perlit cadmium after a period of 30 days. A noticeable increase in the level of cadmium in the plant was observed. Two PCS genes, glutathione gamma-glutamylcysteinyltransferase 1 and glutathione gamma-glutamylcysteinyltransferase and four FC genes, 4 proteins and 4 mRNA were detected in chickpeas. Bioinformatics tools were utilized to predict enzyme structure and binding sites. Chickpea may be classified as a cadmium hyperaccumulator and may be considered for use in phytoremediation. This study provides a better understanding with regards to the response of chickpeas to cadmium and the genetic mechanism by which the plant regulates heavy metal toxicity.