Application of chitosan on plant responses with special reference to abiotic stress

Abstract

Chitosan is a natural biopolymer modified from chitins which act as a potential biostimulant and elicitor in agriculture. It is non-toxic, biodegradable and biocompatible which favors potentially broad application. It enhances the physiological response and mitigates the adverse effect of abiotic stresses through stress transduction pathway via secondary messenger(s). Chitosan treatment stimulates photosynthetic rate, stomatal closure through ABA synthesis; enhances antioxidant enzymes via nitric oxide and hydrogen peroxide signaling pathways, and induces production of organic acids, sugars, amino acids and other metabolites which are required for the osmotic adjustment, stress signaling, and energy metabolism under stresses. It is also known to form complexes with heavy metals and used as tool for phytoremediation and bioremediation of soil. Besides, this is used as antitranspirant compound through foliar application in many plants thus reducing water use and ensures protection from other negative effects. Based on such beneficial properties, chitosan is utilized in sustainable agricultural practices owing to changing climates. Our review gathers the recent information on chitosan centered upon the abiotic stress responses which could be useful in future crop improvement programs.

Chitosan Application in Vineyards (Vitis vinifera L. cv. Tinto Cão) Induces Accumulation of Anthocyanins and Other Phenolics in Berries, Mediated by Modifications in the Transcription of Secondary Metabolism Genes

“…The potential of chitosan application has been studied in many horticultural crops, towards inducement of defense mechanisms, improved agronomic traits, easier post-harvest management of fruits and vegetables, augmented plant growth and physiological activities, including as a bio-fertilizer/fertilizer protectant [5], and enhanced abiotic stress management properties [6]. Some reports demonstrated its potential effect on powdery mildew [7] and gray mold control [8] in grapevine.…”

Foliar Application of Chitosan Increases Tomato Growth and Influences Mycorrhization and Expression of Endochitinase-Encoding Genes

“…El Amerany et al [24] found similar result in tomato plant grown in soil amended with chitosan and compost. The positive effects of Ch on tomato growth and flowering might be due to its properties to act as anti-transpirant, to activate ROS scavenging system, to enhance stomatal conductance, and to stimulate growth of xylem vessels [24,36]. Moreover, application of Ch to leaves is known to increase the rate of photosynthesis leading to improved growth and overall plant development [37].…”

Sugar Beet (Beta vulgaris) Guard Cells Responses to Salinity Stress: A Proteomic Analysis

“…This protein is homologous of chitinase V in Arabidopsis which has a significant role in salt stress in addition to defense against pathogenic attack [43], and loss of function of the gene encoding chitinase-like protein results in overaccumulation of Na + in the cytosol [44]. In stomata, it has been reported that chitosan, which can be produced by chitinase, mediates stomatal narrowing and it may be advantageous for both the salt stress responses and plant defense [45,46].…”