Morphological and physiological alterations in the diatom Gomphonema pseudoaugur due to heavy metal stress

Periphytic diatom communities were analyzed from several heavy metal contaminated water bodies of Haryana, India. Among the analyzed sites, site HO3 (Saraswati Dham, Kurukshetra, Pehowa) showed significant response in the periphytic diatom community in terms of community shift (dominance of Gomphonema pseudoaugur) and lower biodiversity indices (species richness and Shannon index). Gomphonema pseudoaugur responded more specifically through induction of lipid bodies and occurrence of deformities in diatom frustules. PCA analysis showed that site HO3 is contaminated with heavy metals, especially Pb and Se. Pearson's correlation analysis showed a positive and statistically strong relationship between induction of lipid bodies and deformities with heavy metals (Pb and Se). Finally, from the present study, we concluded that heavy metal stress induces increased lipid body (LBs) size and deformities in the diatom species Gomphonema pseudoaugur, which could be a valuable indicator species for biomonitoring and a consideration in biofuel production.