Effects of exogenous melatonin on antioxidant system in leaves of kiwifruit seedlings under cadmium stress

Higgs

Ashraf

et al. 2019

Physiologia Plantarum

249

109

There seems to be no report in the literature on the effect of melatonin (MT) in relieving the detrimental effects of combined application of salt stress (SS) and iron deficiency (ID). Therefore, the effect of MT on the accumulation/synthesis of endogenous nitric oxide (NO) and hydrogen sulphide (H2S) and how far these molecules are involved in MT‐improved tolerance to the combined application of ID and SS in pepper (Capsicum annuum L) were tested. Hence, two individual trials were set up. The treatments in the first experiment comprised: Control, ID (0.1 mM FeSO4), SS (100 mM NaCl) and ID + SS. The detrimental effects of combined stresses were more prominent than those by either of the single stress, with respect to growth, oxidative stress and antioxidant defense attributes. Single stress or both in combination improved the endogenous H2S and NO, and foliar‐applied MT (100 µM) led to a further increase in NO and H2S levels. In the second experiment, 0.1 mM scavenger of NO, 2‐(4‐carboxyphenyl)‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide potassium salt (cPTIO) and that of H2S, hypotuarine (HT) were applied along with MT to get further evidence whether NO and H2S are involved in MT‐induced tolerance to ID and SS. MT combined with cPTIO and HT under a single or combined stress showed that NO effect was reversed by the NO scavenger, cPTIO, alone but the H2S effect was inhibited by both scavengers. These findings suggested that tolerance to ID and SS induced by MT may be involved in downstream signal crosstalk between NO and H2S.

Section: Introductionmentioning

confidence: 99%

Integrative roles of nitric oxide and hydrogen sulfide in melatonin‐induced tolerance of pepper (Capsicum annuum L.) plants to iron deficiency and salt stress alone or in combination

Higgs

Ashraf

et al. 2019

Physiologia Plantarum

249

109

“…This chemical substance has recently gained a ground, because its application to plants can enable them to thrive well under multiple stresses. For example, Huang et al (2017) showed that MT application to kiwi fruit assuaged the injurious effects of Cd by upregulating the antioxidant defense system as well as in peach fruit placed in a cold storage (Cao et al, 2016). MT is also believed to play a promising role in the signal mechanisms of abiotically stressed plants (Martinez et al, 2018) as well as it acts as a powerful ROS scavenger (Allegra et al, 2003).…”

Section: Introductionmentioning

confidence: 99%

Melatonin improves tolerance to salt stress and boron toxicity in soybean and pepper plants

Sarıoğlu

Int. J. Appl. Exp. Biol.

2022

The role of melatonin (MT) in promoting tolerance to salt stress and boron toxicity in soybean and pepper plants was investigated. The treatments comprised: Control (C), salt stress (SS; 100 mM NaCl), boron toxicity (BT; 2 mM B) and SS + BT. Harmful effects of combined stresses resulted in a greater decrease in plant biomass and chlorophyll contents in both plants compared to those of a single stress. However, SS and BT increased electron leakage, and contents of H2O2, proline and MDA, while an increase was observed in the activities of POD, SOD and CAT. Foliar applied MT (100 μM) caused an increase in fresh and dry mass and photosynthetic pigments of plants of both crops under both stresses imposed singly or in combination. However, melatonin reduced electron leakage, and the contents of H2O2 and MDA. Proline contents in the pepper plants increased with MT application, while they decreased in the soybean plants. The activities of vital antioxidant enzymes, POD, SOD and CAT were found to be increased with MT application in both plants.

Effect of bacteria and melatonin application on soil microbial activity on soybean plants grown under salt stress and boron toxicity conditions

Sarıoğlu

Harran Tarım Ve Gıda Bilimleri Dergisi

2021

Bu çalışmada, tuz stresi (TS) ve bor toksisitesi (BT) şartlarında soya bitkisine yapraktan yapılan melatonin (MT) uygulaması ve tohumdan bakteri aşılamasının bitki gelişimi ile topraktaki bazı mikrobiyal aktivitelere etkisi araştırılmıştır. Bu araştırma sera denemesi olarak toprak ortamında saksılarda yürütülmüştür. Araştırma konuları; kontrol, TS (100mM NaCl), BT (2mM B) ve TS+BT (100mM NaCl+2mM B) olarak belirlenmiştir. Araştırma sonuçlarına göre, soya bitkisinde en fazla zarar TS+BT birlikte uygulamasında görülmüştür. Genel olarak yapılan stres uygulamaları bitki yaş ve kuru ağırlıklarında ve DHA, MBC ve CO2 gibi toprak mikrobiyal aktivite içeriklerinde önemli azalmaya neden olmaktadır. Bunun yanı sıra, stres etkilerine karşı yapılan uygulamalardan özellikle bakteri aşılaması (BA) stresin etkilerini hafifletmede etkili olduğu belirlenmiştir. Bununla birlikte yapılan melatonin (MT) uygulaması ise, tek başına BA uygulaması kadar etkili olmamış fakat BA ile stres etkilerini daha fazla azaltmada destek görevi görmüştür. Yapılan BA ve MT uygulamaları ile soya bitkisinde, bitki yaş ve kuru ağırlıklarında ve toprak mikrobiyal aktivitelerinde (DHA, MBC ve CO2) artışlar olduğu tespit edilmiş ve bu artışlar istatistiki (P≤0.05) olarak önemli bulunmuştur.