Variation in Seed Metabolites between Two Indica Rice Accessions Differing in Seed Longevity

Abstract

For a better understanding of germination after seed storage, metabolite profiling was conducted using hybrid triple quadrupole time-of-flight (QTOF) mass spectrometry. After moisture content (MC) equilibration, seeds of “WAS170” (short-lived) and “IR65483” (long-lived) were stored at 10.9% MC and 45 °C. Samples for metabolite analysis were taken after 0 and 20 days of storage. Among 288 metabolites, two flavonoids (kaempferide and quercetin-3-arabinoside), one amino acid (S-sulfocysteine) and one sugar (D-glucose) increased in “IR65483” seeds after storage but were not detected in “WAS170” seeds. Based on the genome sequence database, we identified clear allelic differences with non-synonymous mutations on the six flavonol synthase genes regulating the accumulation of kaempferol- and quercetin-metabolites. On the other hand, two metabolites (thiamine monophosphate and harmaline) increased in short-lived seeds after storage; these metabolites could be potential biochemical indicators of seed deterioration.

Quercetin and Rutin as Tools to Enhance Antioxidant Profiles and Post-Priming Seed Storability in Medicago truncatula

“…Considered together, these results suggest potential protective effects by quercetin or rutin supplementation with priming in terms of enhanced antioxidant profiles. This antioxidant effect of quercetin and rutin is in line with several accounts in other experimental systems, including Apocynum pictum and venetum seeds under osmotic stress [44], G. max artificially aged seeds [43], O. sativa plants [45] and aging seeds [42], and others [41]. Despite the significant correlations, the collected data are not sufficient to distinguish the direct and indirect effects of quercetin or rutin on antioxidant profiles, germination rates and seedling growth, nor the relative contribution of other factors that reportedly contribute to seed longevity.…”

“…The contribution of endogenous flavonoids in seed longevity and storability is documented, including their antioxidant properties associated with their accumulation in seed coat and embryo [41]. Alleles of flavonoid genes and differential accumulation of flavonoids have been indicated as contributors to seed longevity in rice and soybean, respectively [42,43]. Protective effects are reported following the exogenous administration of quercetin, rutin or other flavonoids to seeds, seedlings or adult plants in the form of direct administration or priming treatments, with examples in numerous experimental systems where they reduce ROS accumulation and membrane damage [36,37,44,45].…”