Involvement of Acetaldehyde in Seed Deterioration of Some Recalcitrant Woody Species through the Acceleration of Aerobic Respiration

Abstract

The rate of acetaldehyde (Ald) evolution in the deterioration of recalcitrant woody seeds was investigated. Four plant species, Ligustrum japonicum, Quercus serrata, Quercus myrsinaefolia and Camellia japonica, were used for the experiments. Similar to orthodox seeds, all of the recalcitrant seeds used contained Ald in addition to methanol and ethanol, although the amount of Ald in Camellia, a typical oil seed, was very small. These volatiles were accumulated in a container in which Ligustrum and Q. serrata seeds were stored for a short period. Moreover, all of the seeds that had been previously exposed to Ald for only 6 d at 3 or 13 degrees C lost their vigor rapidly in proportion to the concentration of Ald. The occasional removal by decompression of Ald accumulated in the container prolonged the life span of Q. serrata seeds from 4 to 6 months. These findings suggest that a short life span of the hydrated recalcitrant seeds may involve Ald synthesis as in the orthodox seeds. However, the action mechanism of Ald in Ligustrum and Quercus seeds in which storage substances were polysaccharides seems to differ slightly from that in orthodox seeds, because their aerobic respiration was significantly stimulated by exposure to exogenously applied Ald. It was, therefore, thought that the rapid deterioration of some recalcitrant seeds in woody species may result from a decline in vigor, not only due to the denaturation of functional proteins by Ald as in the orthodox seeds but also due to the rapid consumption of direct substrates for the Ald-stimulated aerobic respiration and related co-enzymes within seeds. In contrast, in the oil-bearing Camellia seeds, Ald was slightly produced and their aerobic respiration was not enhanced by Ald, although they were very sensitive to Ald. Desiccation storage of Camellia seeds caused the deterioration of their outer part, which was accelerated by exogenously applied Ald, which suggests that in Camellia Ald acts only to denature the functional proteins as in orthodox seeds. Thus, the short longevity of these woody recalcitrant seeds is discussed in relation to the actions of Ald produced endogenously.

Optimization and sensitivity analysis of fast ethanol assay in maize seeds

“…The mitochondrial membrane is known to be among the primary sites of deterioration, for instance, during seed ageing, because mitochondrial activity has been clearly demonstrated to be the primary source of energy (adenosine triphosphate) for cells (Delouche and Baskin, 1973;Nelson and Cox, 2012). A decrease in the mitochondrial efficiency is correlated with an increase in the production of volatile compounds, especially ethanol (Akimoto et al, 2004;Colville et al, 2012;Mira et al, 2016;Woodstock and Taylorson, 1981). In the past, the method has been based on benchtop multiparameter instruments, using gas chromatography or enzyme sensor technology, both of which are slow and costly for routine analyses of multiple samples (Bicanic et al, 2003;Kataki and Taylor, 2001;Mira et al, 2010;Mira et al, 2016).…”

“…Kodde et al (2012) reported a fast and reliable method to evaluate seed viability or deterioration using a modified ethanol sensor, or breath analyser, a so-called fast ethanol assay. In a fast ethanol assay, ethanol production by partially imbibed seed is a potential indicator of seed vigour because production from deteriorated seed is relatively high compared to that from high-vigour seed (Akimoto et al, 2004;Buckley and Huang, 2011;Kataki and Taylor, 2001;Kodde et al, 2012). The generation of ethanol can indicate loss of mitochondrial membrane integrity (Brand and Nicholls, 2011;Cossins and Beevers, 1963;Logan et al, 2001).…”

Volatile fingerprints of seeds of four species indicate the involvement of alcoholic fermentation, lipid peroxidation, and Maillard reactions in seed deterioration during ageing and desiccation stress

“…Dehydration of desiccation-sensitive tissues of pea and cucumber radicles was associated with the production of acetaldehyde, indicative of a switch to fermentation, possibly triggered by a disruption of flux through glycolysis, the tricarboxylic acid cycle, or oxidative phosphorylation (Leprince et al ., 2000). Volatile production during deterioration of recalcitrant seeds is not widely reported in the literature, although a study of four recalcitrant species ( Ligustrum japonicum , Quercus serrata , Quercus myrsinaefolia , and Camellia japonica ) found that seeds produced methanol, ethanol, and acetaldehyde during storage, and that the application of exogenous acetaldehyde accelerated deterioration (Akimoto et al ., 2004). …”

Mechanisms underlying detection of seed dormancy by a scatter‐hoarding rodent

“…To test whether low molecular weight lipid peroxidation byproducts could influence seed fate, we presented red oak seeds coated with acetaldehyde to squirrels. Given that lipid peroxidation is potentially involved in the breakdown of waxes in red oak acorns, release of byproducts including acetaldehyde from seeds may be expected (Akimoto et al 2004). Our results show that acetaldehyde-treated seeds were 7 times more likely to be consumed than control seeds (Table 2).…”