ABSTRACT

Phytoremediation has emerged as promising technology for reclamation of metal-polluted sites. The present study was conducted with an aim to assess the hyperaccumulation potential of Ricinus communis for cadmium, with the application of exogenous substances, [nitrogen (N), phosphorus (P) and potassium (K)] and phytohormones [Gibberellic acid (GA₃) and Indole acetic acid (IAA)]. These were applied to increase plant biomass, improve phytoextraction of Cd and its accumulation in aerial parts, with generation of endogenous proline and phenols in R. communis, grown in soil contaminated with 100 mg Cd/Kg. Plant hormones were used only as foliar spray while growth regulators were applied to soil and also used as foliar spray. T4 (Cd+NPK _AS) significantly increased root length, T12 (GA3+ NPK _FS) highly increased stem length and leaf length as compared to control C1 (plant only Cd). FBM was highly increased by N alone or in combination with P, K, and GA₃ foliar sprayed in R. communis. Conclusively, it was found that NPK (foliar) in combination with GA₃ followed by N and IAA, significantly increased biomass, Cd concentration and accumulation in all the treated plants of R. communis. Cadmium bio-concentration values for R. communis were higher than unity (1) i.e. ± 2.54. Highest significant concentration of phenolic and proline in R. communis were recorded in combination treatments of GA₃ and NPK foliar spray while in other plants in NPK addition into soil treatment. Thus, R. communis has the natural potential as hyperaccumulator and further study is required for its industrial implementation in polluted soil.

摘要

植物修复已成为回收金属污染场地的有前途的技术。本研究旨在评估蓖麻对镉的超积累潜力，应用外源物质 [氮 (N)、磷 (P) 和钾 (K)] 和植物激素 [赤霉酸 (GA ₃₎ ) 和吲哚乙酸 (IAA)]。这些被用于增加植物生物量，提高的Cd植物提取及其在地上部分积累，随着一代内源性脯氨酸和酚的蓖麻，生长在土壤污染用100mg镉/公斤。植物激素仅用作叶面喷雾，而生长调节剂用于土壤，也用作叶面喷雾。T4 (Cd+NPK _AS) 根长显着增加，T12 (GA3+ NPK _FS ) 与对照 C1（仅植物 Cd）相比，茎长和叶长显着增加。FBM是高度增加了单独的或与P，K，和GA组合Ñ ₃叶面喷洒在蓖麻。决定性，人们发现，NPK（叶面）与GA结合₃接着加入N和IAA，显著增加的生物量，镉浓度和积累在所有处理过的植物蓖麻。镉生物浓度值蓖麻比一（1），即±2.54更高。在酚类和脯氨酸的最高浓度显著蓖麻记录了GA的组合治疗₃和NPK叶面喷施同时在其他植物中加入NPK进行土壤处理。因此，R.communis具有作为超富集植物的天然潜力，需要进一步研究其在污染土壤中的工业应用。