Effect of Salicyclic Acid and Indole Acetic Acid on Tomato Crop under Induced Salinity and Cadmium Stressed Environment: A Review

Abstract

Tomato is one of the common garden fruits in India and is cultivated worldwide because of its edible fruits that are rich in antioxidants, such as lycopene and carotenoid etc. Although densities of ascorbic acid and B-carotene in tomato are modest compared to some other vegetables, tomato ranks high as a source of vitamins A and C in human diets because of high consumption in many countries of the world. Cadmium (Cd) is probably one of the most toxic heavy metals, particularly at high concentrations, inhibiting plant growth and development, whereas at low concentrations Cadmium may also stimulate growth depending on the plant species. Cadmium can also negatively interfere with important plant processes such as water transport, oxidative phosphorylation in mitochondria, photosynthesis and chlorophyll contents. Salinity reduces plant productivity first by reducing plant growth during the phase of osmotic stress and subsequently by inducing leaf senescence during the phase of toxicity. Salicyclic Acid (SA) and Indole acetic acid (IAA) are involved in the protection of plants against multiple stresses, Such as salinity, water stress, drought stress, and herbicides. Indeed, this may be also reported that Salicyclic acid and Indole acetic acide can ameliorate the injurious effects of heavy metals on plants.

Heavy metal induced regulation of plant biology: Recent insights

“…Ethylene biosynthetic enzyme activities were enhanced upon HM stress by phosphorylation of ACS2 and ACS6 due to activation of MAPKs (Bücker‐Neto et al, 2017). Salicylic acid may reduce HM toxicity by regulating various plant metabolic processes (Guo et al, 2018; Kohli et al, 2018; Safari et al, 2019; Wei et al, 2018), the scavenging, and/or reduced accumulations of ROS and/or an enhancement of antioxidant defence systems (Malik et al, 2019; Mostofa et al, 2019; Wang et al, 2019), the safeguarding and security of the membrane stability (Belkadhi et al, 2015), the interaction with plant hormones (Tamás et al, 2015), the increase of hemoxygenase (Cui et al, 2012), and the enhancement of efficiency.…”

The Role of Salicylic Acid in Plants Exposed to Heavy Metals

“…Recently, it has also been demonstrated that SA could play a pivotal role in protecting plants from environmental stress, including heavy metals (HM). In fact, several recent manuscripts reported that SA can alleviate HM toxicity influencing both their uptake and/or accumulation in plant organs [32][33][34][35][36][37][38], as well as scavenging of reactive oxygen species (ROS) and/or decreasing their accumulation and/or enhancing the antioxidant defense system [39][40][41][42], protecting membrane stability and integrity [43], interacting with plant hormones [44], upregulating heme oxygenase [45], and improving the performance of the photosynthetic machinery [42,46,47].…”