Lanthanum chloride enhances the photosynthetic characteristics and increases konjac glucomannan contents in Amorphophallus sinensis Belval

Abstract

Lanthanum (La) has been used as agricultural inputs in order to enhance yield and improve crop quality. However, little is known about the effect of La on the photosynthesis and growth of Amorphophallus sinensis, a worldwide food source. The effects of La on the photosynthetic and chlorophyll fluorescence parameters, photosynthetic pigments, corm yield, and konjac glucomannan (KGM) of Amorphophallus sinensis were investigated via field experiments. The leaves were sprayed with different concentrations of LaCl3 (20, 80, 160, and 240 mg L-1). The results exhibited an increasing effect of LaCl3 on photosynthetic rate, stomatal conductance, intercellular CO2 concentration, chlorophyll fluorescence parameters, photosynthetic pigments, corm yield, and KGM, when concentration was between 20 and 240 mg L-1 , and the most effective concentration was 160 mg L-1. Therefore, moderate LaCl3 concentration may increase yield of Amorphophallus sinensis by enhancing the photosynthetic efficiency, increasing the corm yield, and KGM contents.

Role of beneficial elements in plants: implications for the photosynthetic process

“…Ma et al (2015) also observed that, in plant roots, about 80% of La NPS were transformed into La carboxylates and phosphates, and only these two forms were found in leaves at similar abundances. In general, the supply of Ce or La to plants, grown with or without stress, improves the PN values, in some cases due to an increase in gs, as it was reported in La-treated plants of Amorphophallus sinensis (Li et al 2020), Ce-treated plants of Phaseolus vulgaris and S. bicolor (Djanaguiraman et al 2018, Salgado et al 2020, or in La-treated Z. mays plants (Cui et al 2019) (Table 6). Moreover, Wu et al (2017) reported that (Djanaguiraman et al 2018, Salgado et al 2020.…”

“…Besides their capability to increase the Chl content improving the light-harvesting complex (Liu et al 2007a, Liu et al 2009, Li et al 2020, Ce increases light absorption as well as the energy transfer within LHCII and from tyrosine residues on the oxidizing side of PSII II to Chl a in the PSII reaction centres (Liu et al 2007b). This is probably explained by the results of Hong et al (2002) in Spinacia oleracea, where they found that La or Ce can replace Mg in the Chl assembling and promote the formation of PSII more significantly than that of PSI.…”

Physiological and Biochemical Behaviours and Antioxidant Response of Helianthus annuus under Lanthanum and Cerium Stress

“…Modulated chlorophyll a fluorescence measurements were performed in Helianthus annuus leaves using a MINI-PAM Portable Chlorophyll Fluorometer (Heinz Walz GmbH, Germany). The maximal photochemical yield (Fv/Fm) and the photochemical efficiency (Fv'/Fm') of photosystem-II (PSII), as well as the non-photochemical quenching coefficient (NPQ), were determined [6,25,26]. The electron transport rate (ETR) and the photosynthetically active radiation (PAR) were also measured.…”

“…Lanthanum (La) and cerium (Ce) are two of the 15 lanthanides of the rare earth elements (REEs) group which are naturally and abundantly existent in the Earth's crust [1][2][3], where the average abundance is 35 µg g −1 in La and 66 µg g −1 in Ce [4]. REEs are widely used in new developed technologies, including electronics, chemical engineering, the electronic aerospace industry, renewable energy, medical sciences, and in agricultural fertilisers [5,6].…”