Glycine betaine modulates chromium (VI)-induced morpho-physiological and biochemical responses to mitigate chromium toxicity in chickpea (Cicer arietinum L.) cultivars

Abstract

Chromium (Cr) accumulation in crops reduces yield. Here, we grew two chickpea cultivars, Pusa 2085 (Cr-tolerant) and Pusa Green 112 (Cr-sensitive), in hydroponic and pot conditions under different Cr treatments: 0 and 120 µM Cr and 120 µM Cr + 100 mM glycine betaine (GB). For plants grown in the hydroponic media, we evaluated root morphological attributes and plasma membrane integrity via Evans blue uptake. We also estimated H+-ATPase activity in the roots and leaves of both cultivars. Plants in pots under conditions similar to those of the hydroponic setup were used to measure growth traits, oxidative stress, chlorophyll contents, enzymatic activities, proline levels, and nutrient elements at the seedling stage. Traits such as Cr uptake in different plant parts after 42 days and grain yield after 140 days of growth were also evaluated. In both cultivars, plant growth traits, chlorophyll contents, enzymatic activities, nutrient contents, and grain yield were significantly reduced under Cr stress, whereas oxidative stress and proline levels were increased compared to the control levels. Further, Cr uptake was remarkably decreased in the roots and leaves of Cr-tolerant than in Cr-sensitive cultivars. Application of GB led to improved root growth and morpho-physiological attributes and reduced oxidative stress along with reduced loss in plasma membrane integrity and subsequently increase in H+-ATPase activity. An increment in these parameters shows that the exogenous application of GB improves the Cr stress tolerance in chickpea plants.

Phytoremediation of chromium, iron and nickel by Indian Rice Plant (Oryza sativa L.): An opportunity for management of multi-metal contaminated tannery wastewaterPhytoremediation of chromium, iron and nickel by Indian Rice Plant (Oryza sativa L.): An opportunity for management of multi-metal contaminated tannery wastewater

“…This rise in chlorophyll levels in the leaves of the rice plant may be due to the presence of Cr, Fe, Ni, etc. These findings are in agreement with the earlier results reported (Farooq et al 2016;Amari et al 2017;Singh et al 2022). Moreover, a reduction was observed in chlorophyll and carotenoid level after the T4 (200mg/kg) PHTMs treatment levels (p<0.05).…”

“…This change may be due to the interference of metals in chlorophyll biosynthesis through direct inhibition of enzymatic steps. For example, high Cr is well reported to hinder the biosynthesis of chlorophyll and decrease total chlorophyll as well as chlorophyll a/b ratio (Singh et al 2022).…”

Hydrogen Sulfide and Silicon Together Alleviate Chromium (VI) Toxicity by Modulating Morpho-Physiological and Key Antioxidant Defense Systems in Chickpea (Cicer arietinum L.) Varieties

“…To measure enzymatic activities, 0.5 g of fresh leaf samples were ground in potassium phosphate buffer solution (pH-6.20) under pre-chilled condition. Different buffer solutions were used for each enzyme ( Singh et al, 2022 ). Thereafter, the samples were centrifuged at 10,000 × g for duration of 15 min at 4°C.…”

“…Plasma membrane (PM) H + -ATPase activity in the fresh leaf samples of chickpea plants based on the detailed protocol of Hejl and Koster (2004) and with minor modifications by Singh et al (2022) . PM H + -ATPase activity was measured by quantifying the release of inorganic phosphate at an absorbance of 700 nm using a spectrophotometer (BRS, Brussels, Belgium).…”

“…Nevertheless, despite its economic and ecological importance, chickpea production has remained low due to various biotic and abiotic stresses and changing environmental conditions ( Varshney, 2016 ; Deokar et al, 2019 ). Amongst abiotic stress, heavy metal stress such as Cr has been found to reduce the productivity of the chickpea cultivars by 72.49 and 86.81%, respectively ( Singh et al, 2022 ).…”