Pot experiments were conducted in a completely randomisedstrip-plot design to investigate the root morphological variations, flowering stages (no. of buds, no. of buds blooming and no. of mature flowers) toxicological, physiological and biochemical changes in an ornamental plant Zinnia elegans (L.) using graded concentrations of hexavalent chromium (K₂Cr₂O₇). The study also assessed the chromium bioaccumulation and translocation potential of Zinnia elegans from the contaminated soil. The physio-morphological parameters such as Chlorophyll a fluorescence transient (O–J–I–P), quantum yield of photosystem II ($\phi$P₀), photosynthetic performance index of primary photochemistry (PI${}_{\mathrm{\phi }}$), length of roots and shoots, biomass, total chlorophyll, carotenoid, protein, proline, reducing sugar content and activity of antioxidant enzymes viz guaiacol peroxidase (POX), ascorbate peroxidase (APX), superoxide dismutase (SOD) and catalase (CAT) were analysed after 30, 45 and 60d of treatment. The experiment showed a relationship between an increase in the accumulation of chromium in root and shoot of plants and an increase in the concentrations of hexavalent chromium. However, the length, biomass, $\phi$P₀, PI${}_{\mathrm{\phi }}$, area under OJIP curve, chlorophyll and protein contents of the plants were decreased at higher concentration of Cr${}^{+6}$ (75ppm). disturbance indices $M_0$ and $V_{\mathrm{J}}$ derived from Chl. a fluorescence exhibited higher values indicating Cr${}^{+6}$ induced stress at higher concentrations (>50ppm). However, the activity of antioxidant enzymes and proline contents were increased with the application of higher concentration of chromium, which indicates that the plants adaptive defense system relating to elevated Cr${}^{+6}$ induced oxidative stress. The number of root hairs initially decreased with increase in the concentration of Cr${}^{+6}$ but at higher concentration of Cr${}^{+6}$ (75ppm) the number of root hairs were increased. The number of flowers and overall photosynthetic performance increased with the increase in Cr${}^{+6}$ concentration up to 25ppm. At the highest concentration of Cr${}^{+6}$ (75ppm), treated plants exhibited the least number of mature flowers. The experiments suggest that the Cr${}^{+6}$ stress leads leads to early flowering in Zinnia elegans L. species. This study demonstrates that phytoremedation of Cr${}^{+6}$ contaminated soils in mining sectors can be effectively carried out using non edible ornamental plants, thereby arresting the effects of the ion in the food chain.

在完全随机的带状图设计中进行盆栽实验，以研究观赏植物百日草线虫的根系形态变化，开花阶段（芽数，芽数和成熟花数）的毒理，生理和生化变化（L.）使用分级浓度的六价铬（K ₂ Cr ₂ O ₇）。该研究还评估了被污染土壤中百日草的铬生物富集和迁移潜力。诸如叶绿素a荧光瞬态（O–J–I–P），光系统II的量子产率（$\phi$P ₀），初级光化学的光合性能指数（PI${}_{\mathrm{\phi }}$），根和芽的长度，生物量，总叶绿素，类胡萝卜素，蛋白质，脯氨酸，还原糖含量和抗氧化酶的活性，例如愈创木酚过氧化物酶（POX），抗坏血酸过氧化物酶（APX），超氧化物歧化酶（SOD）和过氧化氢酶（CAT）在治疗30、45和60天后进行分析。实验表明，植物根部和枝条中铬的积累量增加与六价铬浓度的增加之间存在关系。但是，长度，生物量，$\phi$P ₀，${}_{\mathrm{\phi }}$Cr浓度高时，OJIP曲线下的面积，叶绿素和蛋白质含量降低${}^{+6}$（75ppm）。干扰指数${\mathrm{中号}}_0$ 和 $V_{\mathrm{Ĵ}}$衍生自Chl。一个荧光表现出较高的值指示的Cr${}^{+6}$较高浓度（> 50ppm）时引起的压力。然而，随着铬浓度的增加，抗氧化酶的活性和脯氨酸的含量增加，这表明植物的适应防御系统与铬的升高有关。${}^{+6}$诱导的氧化应激。根毛的数量最初随着Cr浓度的增加而减少${}^{+6}$ 但铬含量较高${}^{+6}$（75ppm）的根毛数量增加了。随着Cr含量的增加，花的数量和整体光合性能均升高${}^{+6}$浓度高达25ppm。铬含量最高时${}^{+6}$（75ppm），处理过的植物显示出最少数量的成熟花。实验表明，铬${}^{+6}$胁迫导致百日草线虫物种早开花 。这项研究表明铬的植物除草剂${}^{+6}$ 使用非食用观赏植物可以有效地开采采矿业中被污染的土壤，从而抑制食物链中离子的影响。