Rajinder Kaur Gill is working as Associate Professor in the Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, Punjab, India. Her area of research is environmental sciences, solid waste management, pytotoxicity of environmental pollutant on aquatic as well as terrestrial plants. She has more than 35 publications including research papers and book chapters in reputed journals and books. She has also published a book entitled: Flowering Plants for Bioaesthetic Planning.

The presence of phthalate esters (PAEs) in different components of environment has raised serious concern because of their adverse health effects on man, animal and plant life (Kumari and Kaur, 2018). They are organic compounds and exist in a free and leachable form in the matrix of many usable products such as polyvinylchloride. Some of PAEs has been classified as ‘priority control environmental pollutants’ by the United States Environmental Protection Agency (Liao et al., 2010). Most of these PAEs have endocrine disrupting properties with possible effects on general metabolism and reproductive health (Safe Drinking Water and Toxic Enforcement Act of (1986). In the present study, the effect of two phthalates viz. benzyl butyl phthalate (BBP) and di-n-butyl phthalate  (DBP) on Hordeum valgare L. (barley) was investigated.

Barley is least explored crop plant under phthalates stress. It is an important cereal crop and belongs to family Poaceae. The studies were carried out under in vitro and in vivo conditions. The effect of phthalates was observed on seed germination and seedling development under in vitro conditions for 7 days, while under in vivo conditions the effect was studied on barley plants grown in earthen pots under normal environmental conditions for 120 days.

In germination studies, the effect of phthalates was studied for percent germination, germination speed, peak value, germination vigour index, germination rate index, seed mortality, mean daily germination, mean germination time and germination value. The growth of seedlings in terms of shoot length, root length, shoot fresh weight, root fresh weight, shoot dry weight, root dry weight, shoot weight ratio, root weight ratio, shoot/root ratio, root/shoot ratio and net primary productivity was also investigated. In these 7 days studies, we found that BBP and DBP adversely affected the germination and growth of barley seedlings. The toxic effects of these phthalates on seedlings are evident in confocal and SEM studies. When plants were grown under in vivo conditions, marked changes in morphology and physiology were observed in treated plants as compared to control. To visualize the effect biochemical studies were done by observing the content of pigments, carbohydrate, protein, proline, hydrogen peroxide, malondialdehyde and the specific activities of different antioxidative enzymes viz. superoxide dismutase, guaiacol peroxidase, catalase, ascorbate peroxidase and glutathione reductase. A significant alteration in biochemical parameters of treated plants were observed as compared to control. In most of the observations, the effect was found dose dependent.