Cell Wall Metabolism in Response to Abiotic Stress

Abstract

This review focuses on the responses of the plant cell wall to several abiotic stresses including drought, flooding, heat, cold, salt, heavy metals, light, and air pollutants. The effects of stress on cell wall metabolism are discussed at the physiological (morphogenic), transcriptomic, proteomic and biochemical levels. The analysis of a large set of data shows that the plant response is highly complex. The overall effects of most abiotic stress are often dependent on the plant species, the genotype, the age of the plant, the timing of the stress application, and the intensity of this stress. This shows the difficulty of identifying a common pattern of stress response in cell wall architecture that could enable adaptation and/or resistance to abiotic stress. However, in most cases, two main mechanisms can be highlighted: (i) an increased level in xyloglucan endotransglucosylase/hydrolase (XTH) and expansin proteins, associated with an increase in the degree of rhamnogalacturonan I branching that maintains cell wall plasticity and (ii) an increased cell wall thickening by reinforcement of the secondary wall with hemicellulose and lignin deposition. Taken together, these results show the need to undertake large-scale analyses, using multidisciplinary approaches, to unravel the consequences of stress on the cell wall. This will help identify the key components that could be targeted to improve biomass production under stress conditions.

Genetic variability in storage root bulking of cassava genotypes under irrigation and no irrigation

“…This pattern depends on the growth conditions, particularly moisture, which may affect the choice of sink [4,20]. Different plant organs are affected differentially by stress conditions and could show different trends [28,29]. The pattern of storage root development in this study varied among the genotypes under irrigation and no irrigation as shown by the trend in the storage root length: girth ratio.…”

Physiological, Morphological and Molecular Mechanisms for Drought Tolerance in Rice

“…Responses to drought stress are commonly dependent on plant genotypes, plant species, age of plant, its developmental stage and the severity of drought (Ali et al, 2011;Gall et al, 2015). Three mechanisms, namely drought escape, drought avoidance and drought tolerance are involved in drought resistance.…”

Efeito do déficit hí­drico e CO₂ elevado sobre substâncias fenólicas e ligninas do sorgo var. 'BRS 330'

“…Todos esses constituintes conferem flexibilidade, rigidez e resistência necessárias para o crescimento, manutenção e defesa da célula (Le Gall et al, 2015). A parede celular submetida a fatores internos e externos (ambientais) devem resistir a pressões de turgescência, expansão e relaxamento .…”

“…Alterações nos fatores bióticos e abióticos promovem modificações no acúmulo de ligninas e de outros componentes da parede celular (Moura et al, 2010;Le Gall et al, 2015). Nesse sentido, absorção insuficiente de água, motivada por déficit hídrico severo, limita o desenvolvimento normal das culturas.…”

“…Sinais fenotípicos em gramíneas, como murchas antecipadas, enrolamento das folhas e diminuição do comprimento dos entrenós de colmos têm sido associados a mecanismos adaptativos ao déficit hídrico (Le Gall et al, 2015;Perrier et al, 2017).…”