Combined Kinetin and Spermidine Treatments Ameliorate Growth and Photosynthetic Inhibition in Vigna angularis by Up-Regulating Antioxidant and Nitrogen Metabolism under Cadmium Stress

Abstract

Pot experiments were conducted to investigate the probable beneficial role of the individual as well as combined application of kinetin (50 μM Kn) and spermidine (200 μM Spd) on Vigna angularis under cadmium (Cd) stress. Cd treatment reduced growth by declining the content of chlorophylls and carotenoids, photosynthesis, and gas exchange parameters. Exogenously, Kn and Spd application enhanced the photosynthetic parameters and up-regulated the antioxidant system by improving the activities of antioxidant enzymes and the content of non-enzymatic components. In addition, the application of Kn and Spd resulted in significant improvement in the content of sugars, proline, and glycine betaine, ameliorating the decline in relative water content. Oxidative stress parameters including hydrogen peroxide, superoxide, lipid peroxidation, lipoxygenase activity, and electrolyte leakage increased due to Cd stress; however, the application of Kn and Spd imparted a significant decline in all these parameters. Further, reduced Cd uptake was also observed due to Kn and Spd application. Total phenols and flavonoids also increased due to Kn and Spd treatments under normal as well as Cd stress conditions, which may have further helped with the elimination of reactive oxygen species. Reduction in the activity of nitrate reductase and the content of nitrogen was ameliorated due to the exogenous application of Kn and Spd. Therefore, the exogenous application of Kn and Spd benefited Vigna angularis counteracting the damaging effects of Cd stress by up-regulating the tolerance mechanisms, including antioxidant and osmolyte metabolism.

Kinetin mitigates Cd-induced damagesto growth, photosynthesis and PS II photochemistry of Trigonella seedlings by up-regulating ascorbate-glutathione cycle

“…Cytokinins (CKs) for example, take part in numerous physiological activities such as cell division and morphogenesis, flower and seed development and chloroplast development [12][13][14][15][16]. CKs can also regulate the abiotic stresses by the up-regulation of nitrogen metabolism and antioxidant defense system of plants [12,[17][18][19][20][21]; the importance of CKs in the regulation of heavy metal stress tolerance in plants is well known [11,17,18,22], but the mechanism of CKs induced regulation of heavy metal stress tolerance needs further investigation. The work reported here aimed to determine the effect of exogenous application of different level of KN (KN L , KN M and KN H ) on Trigonella seedlings (in order to counteract Cd phyto-toxicity) by examining their effects on growth and photochemistry of the PS II and AsA-GSH cycles.…”

Reactive Oxygen Species and Antioxidant Defense in Plants under Abiotic Stress: Revisiting the Crucial Role of a Universal Defense Regulator

“…For example, Cd stress (100 µM CdCl 2 ) resulted in increased MDA and H 2 O 2 in Arabidopsis thaliana [ 103 ] and Cucumis sativus seedlings [ 104 ]. In a recent study, Ahanger et al [ 105 ] reported that lipid peroxidation, EL, H 2 O 2 , and O 2 •− contents as well as LOX activity were markedly increased in V. angularis seedlings under Cd stress (100 µM CdCl 2 , 20 d), while a similar increase in EL, H 2 O 2 and TBARS contents was recorded in Mentha arvensis under Cd stress (50 µM CdCl 2 , 100 d) [ 106 ]. Hasanuzzaman et al [ 107 ] demonstrated higher MDA, H 2 O 2 , and O 2 •− content in wheat plants subjected to lead (Pb) stress (0.5 and 1.0 mM Pb(NO 3 ) 2 ) compared with control.…”

“…Moreover, Ni stress-induced enhancement of SOD, GPX, APX, MDHAR, DHAR, and GR activities, which was further upregulated by Si supplementation that helped to minimize Ni toxicity. Ahanger et al [ 105 ] reported an increment in GSH and tocopherol content along with SOD, GST, and DHAR activities with higher H 2 O 2 (61%) and O 2 •− (47%) content in Cd-stressed (100 µM CdCl 2 , 20 d) V. angularis seedlings, whereas AsA levels and CAT activity declined. Contrarily, SOD, CAT, POX, and GR activities were upregulated with higher content of H 2 O 2 (53.45% and 69.83%, respectively) under Cd stress (50 µM CdCl 2 , 100 d) in two Mentha arvensis (cv.…”

Effect of the diverse combinations of useful microbes and chemical fertilizers on important traits of potato

“…But, the inappropriate application of fertilizers, drastically disturbs the soil ecosystem and increases heavy metal intoxication ( Ozturk et al, 2011 , Saini et al, 2019a ). Pb, Cd, Ni and Cr are the significant elements present in fertilizers and pesticides can cause biomagnification, out of which Pb and Cd are toxic to potato plant and humans upon consumption even at low concentration ( John et al, 2009 , Bali et al, 2018 , Bali et al, 2019a , Bali et al, 2019b , Jan et al, 2018 , Kaur et al, 2017 , Kaya et al, 2020a , Kaya et al, 2020b , Kaya et al, 2020c , Ahanger et al, 2020 ).…”