Among the heavy metal pollutants, Cr (VI) is very toxic to plants because of its mobile nature. Silicon (Si) is a metalloid and is reported to ease the negative effects of heavy metal stress in plants. Thus, the current study was conducted to examine the influence of chromium (Cr) toxicity and the mitigating role of silicon (Si) in tomato plants. Chromium toxicity induced high accumulation of Cr in roots and shoots, thereby decreasing plant growth and biomass yield. Silicon supplementation enhanced the afore-mentioned parameters except Cr accumulation. Silicon also enhanced the translocation factor, total chlorophyll, F_v/F_m, Φ_PSII, Φ_exc and q_p but at the same time it decreased NPQ in Cr-stressed plants. The gaseous exchange and relative water content (LRWC) of leaf were improved by Si, that were initially decreased by Cr noxiousness. Malondialdehyde (MDA), hydrogen peroxide, (H₂O₂) and electrolyte leakage (EL) increased with Cr toxicity, but were reduced with Si application. Cr toxicity boosts the enzyme concentration, and Si supplementation thereafter increased the activities of the enzymes as well as metabolite cycle (Asc–Glu). Chromium stress increased methylglyoxal (MG) by 116.87%, which was reduced by Si supplementation. Silicon increased GlyI (EC: 4.4.1.5) and GlyII (EC: 3.1.2.6) thereby making the glyoxalase system more active for providing tolerance to tomato plants. In conclusion, Cr toxicity triggers detrimental effect on plant growth and physio-biochemical processes. However, Si supplementation reversed partially the Cr toxicity by modulating the levels of osmoprotectants, antioxidant enzyme activities, Asc–Glu cycle and the glyoxalase system.

在重金属污染物中，Cr (VI) 因其可移动性而对植物具有很强的毒性。硅 (Si) 是一种准金属，据报道可以缓解植物中重金属胁迫的负面影响。因此，目前的研究旨在检查铬 (Cr) 毒性的影响和硅 (Si) 在番茄植物中的缓解作用。铬毒性会导致根和芽中 Cr 的大量积累，从而降低植物生长和生物量产量。除 Cr 积累外，硅补充增强了上述参数。硅还增强了易位因子、总叶绿素、F _v / F _m、Φ _PSII、Φ _exc和q _p但同时它降低了 Cr 胁迫植物的 NPQ。Si提高了叶片的气体交换和相对含水量（LRWC），而Cr毒性最初降低了叶片的气体交换和相对含水量（LRWC）。丙二醛 (MDA)、过氧化氢、(H ₂ O ₂ ) 和电解液泄漏 (EL) 会随着 Cr 的毒性而增加，但随着 Si 的应用而减少。Cr 毒性会提高酶浓度，此后补充 Si 会增加酶的活性以及代谢物循环 (Asc-Glu)。铬胁迫使甲基乙二醛 (MG) 增加了 116.87%，而 Si 补充则减少了。硅增加 GlyI ( EC: 4.4.1.5 )和 GlyII (EC: 3.1.2.6) 从而使乙二醛酶系统更活跃，以提供对番茄植物的耐受性。总之，Cr 毒性对植物生长和生理生化过程产生不利影响。然而，Si 补充通过调节渗透保护剂、抗氧化酶活性、Asc-Glu 循环和乙二醛酶系统的水平部分逆转了 Cr 毒性。