Characterization of cold-induced changes in the fatty acids profile of rice seedlings

Abstract

Rice, a staple food for more than one half of the world's population, is one of the most cold-sensitive cereals. Breeding programs aimed at increasing rice production are expected to reduce cold-imposed grain losses. Several reports have demonstrated that cold induce differential effects on the fatty acids profile of membranes in chilling-sensitive and chilling-tolerant plants. In this work, we evaluated changes in fatty acid (FA) composition as a potential screening tool to evaluate chilling sensitivity of rice accessions. Cold exposure led to the preferential accumulation of the polyunsaturated linolenic and linoleic FAs and reduction of palmitic and stearic FAs, besides showing increased lignoceric acid content in roots of the variety. Similarly, roots of cold-exposed line Quila 66304 also presented preferential accumulation of linolenic and linoleic FAs and reduction of palmitic and stearic FAs. Cold exposure also led to enhanced levels of palmitic acid in shoots of Amaroo and, in a smaller extent, in shoots of Quila 66304. Linolenic acid was reduced in the shoots of both Amaroo and Quila 66304, while oleic acid content was reduced in shoots of Amaroo and slightly increased in shoots of Quila 66304. Double-bond index analysis indicated that 18 carbons FAs DBI for roots might be a good screening tool for cold response in rice. Results in this report demonstrate that cold-induced changes in FA profile represent a useful screening tool for early identification of differences in cold acclimation potential among rice accessions. Keywords Cold sensitivity Á Double-bond index Á Oryza sativa Á Polyunsaturated fatty acid Communicated by J.-H. Liu.

Speed versus endurance tradeoff in plants: Leaves with higher photosynthetic rates show stronger seasonal declines

“…In addition, this tradeoff could arise in part from variation in relative investment in biochemical chilling resistance. Chilling resistance is related to the desaturation degree of the membrane fatty acids 28 , high plasticity of photochemistry 29 , compatible solute concentration 30 , and proteins related to soluble sugar synthesis and antioxidant processes 31 , all of which may potentially decrease the nutrient investment in photosynthetic capacity and contribute to the formation of the trade-off between maximum performance and seasonal maintenance. Additionally, leaves with high photosynthetic capacity generally require high water transport to meet the associated high transpirational demand, which may be associated with greater vulnerability to loss of hydraulic conductance and larger declines in photosynthesis under adverse conditions 32 .…”

Fructan metabolism and changes in fructan composition during cold acclimation in perennial ryegrass

“…Rearrangements of cytoskeletal structures in response to low-temperature stress are important for morphological and physiological changes in roots required for the acquisition of freezing tolerance (Kerr and Carter, 1990 ). Plasma membrane lipid alterations such as compositional changes in fatty acids have also been shown as adaptive traits during cold acclimation (Lee et al, 2005 ; Sassaki et al, 2013 ). Exposure of rice roots to low-temperature stress resulted in a gradual increase of root water uptake and induction of genes encoding aquaporins (Ahamed et al, 2012 ).…”

“…A period of low temperature stress (cold acclimation) induces morphological, physiological, and biochemical changes in both shoot and root tissues that are required for the acquisition of freezing tolerance in cold-tolerant plants (Kerr and Carter, 1990 ; Goulas et al, 2003 ; Hoffmann et al, 2010 ). The alterations in cytoskeletal structures (Kerr and Carter, 1990 ), plasma membrane lipid alterations (Sassaki et al, 2013 ), accumulation of compatible solutes (Castonguay et al, 1995 ) has been shown in the root tissues. Cold acclimation has been shown by upregulation of proteins involved in stress responses and metabolic activities such as glycolysis, nucleoside metabolism, and carbohydrate metabolism.…”

Characteristic Identification of Heat Exposure Based on Disaster Events for Single-Season Rice along the Middle and Lower Reaches of the Yangtze River, China

“…Rice (Oryza sativa L.) is a crucial cereal grain worldwide, serving as a primary source of sustenance for over 50% of the world's population. Around 160 million hectares of agricultural land are dedicated to rice cultivation worldwide [1]. Experts estimate that the production of rice and other crops must increase by over 70% to meet the dietary demands of the world's rapidly growing population by the year 2050.…”

“…In this paper, we used historical rice heat-disaster representations in MLRYR to determine the triggering threshold of heat stress occurrence and characterize single-season rice exposure to heat stress. The main objectives are: (1) to investigate the key phenological stages of rice exposure to heat stress based on the historical disaster data; (2) to quantify the critical temperature threshold for heat stress to single-season rice at different phenological stages; and (3) to delineate the characteristics of heat exposure, which can help us to develop strategies for adaptation to heat stress in MLRYR.…”