The wastewater utilization for irrigation purposes is common practice in peri-urban areas located in vicinity of developed cities. This water contains elements like chromium (Cr), nickel (Ni), cadmium (Cd) and nitrate (NO₃-N) that poses health risk when exposed to human. In this study effect of wastewater irrigation from Chakara wastewater plant, Faisalabad on growth of wheat and health risks was assessed. Pot experiment was conducted at Institute of Soil and Environmental, University of Agriculture, Faisalabad using different concentration of wastewater as treatment 100% tap water, 25% wastewater + 75% tap water, 50% wastewater + 50% tap water, 75% wastewater + 25% tap water, 100% wastewater. The results indicated that the wastewater irrigation negatively effects the plant growth and physiological parameters. The minimum plant height, grain weight, spike length, osmotic potential and SPAD values were recorded 50.33 cm, 1.47 g plant^-1, 7.00 cm, 423 and 38.91 respectively in 100% wastewater irrigation. The risk quotient (RQ _TEs) for each toxic element and cumulative risk index (RI _TEs) values were calculated. The cadmium risk quotient (Cd _RQ) for adults was on margin and value was >1 for in 75% wastewater + 25% tap water and 100% wastewater irrigation, while the RQ for Ni and Cr was <1. Maximum RI _TEs values calculated in 100% wastewater irrigation 0.424 and 0.294 for children and adults respectively. Hence it was concluded that wastewater irrigation significantly increased the accumulation rate of metals and nitrate in wheat and cause potential health risks for children and adults.

Soil salinity, drought, and increasing temperatures are serious environmental issues that drastically reduce crop productivity worldwide. Quinoa (Chenopodium quinoa Willd) is an important crop for food security under the changing climate. This study examined the physio-biochemical responses, plant growth, and grain yield of four quinoa genotypes (A7, Titicaca, Vikinga, and Puno) grown in pots containing normal (non-saline) or salt-affected soil exposed to drought and elevated-temperature treatments. Combinations of drought, salinity, and high-temperature stress decreased plant growth and yield more than the individual stresses. The combined drought, salinity, and heat stress treatment decreased the shoot biomass of A7, Puno, Titicaca, and Vikinga by 27, 36, 41, and 50%, respectively, compared to that of control plants. Similar trends were observed for grain yield, chlorophyll contents, and stomatal conductance. The combined application of these three stresses increased Na concentrations but decreased K concentrations in roots and shoots relative to control. Moreover, in the combined salinity, drought, and high-temperature treatment, A7, Puno, Titicaca, and Vikinga had 7.3-, 6.9-, 8-, and 12.6-fold higher hydrogen peroxide contents than control plants. All four quinoa genotypes increased antioxidant enzyme activities (CAT, SOD, and POD) to overcome oxidative stress. Despite A7 producing the highest biomass under stress, it did not translate into increased grain production. We conclude that Puno and Titicaca are more tolerant than Vikinga for cultivation in salt-affected soils prone to drought and heat stress.

There is a very narrow margin in selenium deficiency and toxicity although it is an important element for humans, animals, and plants. Effects of selenium (Se) on the growth and physiomorphological parameters in maize were studied grown in soil spiked with sodium selenate (Na₂SeO₄) in 5 different concentrations (i.e., 0. 2.5, 5.0, 10.0, and 20.0mgkg⁻¹). The growth of plants was affected by high Se concentration. However, maximum increases in plant height and root length were observed at low Se (2.5mgkg⁻¹) which were 17.89 and 23.17, respectively. At higher Se concentrations (20mgkg⁻¹), a considerable reduction was observed in dry matter, root length, antioxidant enzymes, and other physiological parameters. The dry matter of plants was also analyzed for nutrient (Fe and Zn) concentrations. Results indicated that Se stress inhibits plant growth. Gas exchange parameters were also found to be decreased under stress conditions, but at a lower Se level (2.5mgkg⁻¹), improvement in transpiration rate (63.46), photosynthetic rate (47.47), and stomatal conductance (54.55) was observed. The reduction in growth attributes may be due to the high accumulation of Se in roots and the disturbance in gas exchange parameters. However, the principal component analysis revealed that higher Se levels were more hazardous for maize growth and physiological responses as compared to low Se levels.