Potential of Plant Growth Regulators to Enhance Arsenic Phytostabilization by Pennisetum purpureum cv. Mott

Abstract

The limited translocation of arsenic from contaminated soil to plant biomass is one way to decrease human exposure to arsenic (As). Plant growth regulators (PGR), including salicylic acid, indole butyric acid, and calcium, have been reported to alleviate toxicity and decrease the accumulation of heavy metals in many plants. Thus, this study has investigated the effect of plant growth regulators, including salicylic acid, salicylic acid + calcium chloride, indole butyric acid, and indole butyric acid + calcium chloride, to stimulate the growth and phytostabilization of Pennisetum purpureum cv. Mott grew in arsenic-spiked soil. The results showed shoot growth, root growth, and total chlorophyll content of P. purpureum cv. Mott grown in non-spiked soil were not significantly different from those grown in arsenic-spiked soil. Only the root-to-shoot ratio of plants grown under arsenic-spiked soil (0.28) was higher than that of non-spiked soil (0.19). Exogenous plant growth regulator application of each formula did not stimulate the growth of plants grown under both soil conditions. The most suitable plant growth regulator was indole butyric acid + calcium chloride, as the highest arsenic accumulation in plant roots was detected (47.38 mg/kg). It corresponds with the arsenic bioaccumulation factor, translocation factor, and efficiency, which were 4.52, 0.06, and 9.77% when using exogenously indole butyric acid + calcium chloride. Meanwhile, arsenic’s translocation factor and efficiency were low when using the other formulae of plant growth regulators. Thus, 0.001 mM indole butyric acid + 20 mM calcium chloride may be used for the cultivation of P. purpureum cv. Mott as a forage crop in areas with low levels of arsenic contamination because it could limit the amount of arsenic entering the food chain.

Nutrient Value and In Vitro Digestibility of Pennisetum purpureum cv. Mott under Varying Gamma Irradiation Doses in Acidic Soil

“…purpureum cv. Mott, also known as elephant grass or Napier grass, is a versatile forage crop with remarkable characteristics (Chouychai & Somtrakoon, 2022). It is well-suited for cultivation in marginal lands due to its adaptability to various environmental conditions (Putra et al, 2022b).…”

Radiosensitivity Assessment and the Impact of Gamma Radiation on the Growth and Diversity of Pennisetum purpureum Cv Mot in Marginal Land

“…Furthermore, Pennisetum purpureum cv. Mott has found utility in phytoremediation, specifically in soils contaminated with substances such as Arsenic (As) (Chouychai and Somtrakoon, 2022;Kowitwiwat and Sampanpanish, 2020) and heavy metals (Putra et al, 2022), However, it exhibits limitations in adapting to saline soil conditions (Pongtongkam et al, 2006) and faces challenges related to biomass production and root growth in acidic soils (Putra et al, 2022;Kowitwiwat and Sampanpanish, 2020) reported reduced chlorophyll content in Pennisetum purpureum cv. Mott when grown in tailing soil contaminated with heavy metals.…”

Application of Salicylic Acid and Gibberellic Acid Increase Stem Cutting Growth of Pennisetum purpureum cv. Mahasarakham and Pennisetum purpureum x Pennisetum americanum

“…Napier grass was reported to be an effective choice for phytoremediation. Dwarf Napier grass has been reported to phytostabilize arsenic in soil (Chouychai & Somtrakoon, 2022;Kowitwiwat & Sampanpanish, 2020). This grass species is also reportedly used in the phytoremediation of petroleum hydrocarboncontaminated soil (Ologidi et al, 2022).…”