Chitosan enhances rice seedling growth via gene expression network between nucleus and chloroplast

Abstract

Chitosan, a partially deacetylated form of the natural and biodegradable biopolymer chitin, has been used as plant growth promoter in agriculture. The aim of this work was to investigate the growth promoting responses induced by chitosan at the physiological and molecular level in rice (Oryza sativa L.) seedlings. The combination of the degree of deacetylation (DD), molecular weight and concentration of chitosan had differing effects on the rice seedling growth. For the best enhancement, oligomeric chitosan with an 80 % DD applied at 40 mg/L significantly enhanced the vegetative growth, in terms of the leaf and root fresh weights and dry weights of rice seedlings compared to the control. At the proteomics level, of the 352 rice leaf proteins that could be resolved using the Multi Experiment Viewer software, 105 showed a significantly different expression level in rice leaves treated with chitosan compared to the control. Co-expression network analysis revealed nine of these proteins had significant coexpression with other genes from the three main biochemical network systems of photosynthesis, carbohydrate metabolism and cell redox homeostasis. More than 90 % of the genes positively co-expressed with these nine chitosanresponsive proteins were localized in chloroplasts, suggesting that chitosan enhanced the plant growth of rice seedlings via multiple and complex networks between the nucleus and chloroplast.

Biostimulant activity of chitosan in horticulture

“…Moreover, changes in the expression level of the chloroplastic gene, ycf1, after 48 h of chitosan application in Dendrobium 'Eiskul' were detected, followed by chloroplast enlargement after 68 weeks (Limpanavech et al, 2008). A subsequent proteomics analysis for chitosan responsive proteins in rice leaves revealed that chitosan induced significant expression level changes in 352 proteins, while a co-expression network analysis revealed that many co-expressed proteins were localized in the chloroplasts (Chamnanmanoontham et al, 2015).…”

Preparation and Foliar Application of Oligochitosan - Nanosilica on the Enhancement of Soybean Seed Yield

“…Therefore, Yin et al (2010) supposed oligochitosan as a plant vaccine that is similar with general animal vaccine [8]. Beside elicitation effect, oligochitosan also exhibits growth promotion effect for plant such as rice [9], soybean [10,11], etc. It is interesting to note that application of oligochitosan either by seed treatment [10] or through hyponex solution [11] increased seed yield of soybean from 15 to about 36%.…”

Inhibition of IAA oxidase activity of wheat anionic peroxidase by chitooligosaccharides

“…The products of these genes include proteins of kinase cascade, lectin-like proteins, and zinc finger protein, as well as the protein kinase AtMPK3, which is involved in the signaling cascade and performs the reception functions, signal transduction, and transcriptional regulation. A number of proteins responsible for the growth and formation of close associations of nuclear and chloroplast genomes that accumulated under the effect of chitosan (352 proteins) were detected as the result of the analysis of the rice plant proteome [1].…”

“…Among bioactive compounds, oligosaccharides, which may possess growth-regulatory activities depending on their structure, origin, and concentration, are of particular interest [1,2]. Thus, the growth of orchids (Dendrobium bigibbum var.…”