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Intraspecific variation in seed production schedule and its effects on seed characteristics were examined in the deciduous oak species Quercus serrata in Iwate Prefecture, northern Japan. Seed production schedule differed markedly among 31 individual trees. The median dates of seed production differed by over 1 month between the earliest and latest individuals. Relationships between seed production schedule and seed characteristics were investigated at two different scales: the among-tree scale and the within-tree scale. At the within-tree scale, analyses revealed that the seeds dispersed by a tree later in the season tended to be larger in size and lower in tannin concentration. Similarly, at the among-tree scale, analysis revealed that trees with a later seed production schedule produced on average larger acorns. However, no clear tendency was observed between seed production schedule and mean tannin concentration. The observed variation in seed production schedule is likely to affect seed fate per se, and also via changes in seed characteristics. [ABSTRACT FROM AUTHOR]

Abstract: Tannins are very common among plant seeds but their effects on the fate of seeds, for example, via mediation of the feeding preferences of scatter-hoarding rodents, are poorly understood. In this study, we created a series of artificial ‘seeds’ that only differed in tannin concentration and the type of tannin, and placed them in a pine forest in the Shangri-La Alpine Botanical Garden, Yunnan Province of China. Two rodent species (Apodemus latronum and A. chevrieri) showed significant preferences for ‘seeds’ with different tannin concentrations. A significantly higher proportion of seeds with low tannin concentration were consumed in situ compared with seeds with a higher tannin concentration. Meanwhile, the tannin concentration was significantly positively correlated with the proportion of seeds cached. The different types of tannin (hydrolysable tannin vs condensed tannin) did not differ significantly in their effect on the proportion of seeds eaten in situ vs seeds cached. Tannin concentrations had no significant effect on the distance that cached seeds were carried, which suggests that rodents may respond to different seed traits in deciding whether or not to cache seeds and how far they will transport seeds. [Copyright &y& Elsevier]

• Aroma does not have a main effect on taste or mouthfeel perception of red wines. • The only effect of aroma was observed for oily mouthfeel. • Oily mouthfeel was masked by earthy aromas and enhanced by alcoholic nuances. • Independent dimensions were related to dry/silky, grainy, prickly and oily. • Tannin concentration and activity and pH drove wine dryness. The present study was aimed at increasing the understanding of red wine mouthfeel by investigating the potential cross-modal effect of aroma and establishing relationships between sensory dimensions and chemical measurements. Investigations involved a set of 42 non-wooded red wines that were described with a novel application of a variant of the rate-all-that-apply sensory methodology ("rate- K attributes") by a group of Spanish wine experts under two conditions: (1) with no aroma perception (using nose clips) and (2) with aroma perception. In parallel, ethanol content, pH, titratable acidity, tannin activity, concentration of tannins, and spectroscopic measures of wines were determined. Results suggest that aroma does not play a main effect on taste or mouthfeel perception of red wines, except for oily mouthfeel, which was hypothesised to be masked by earthy aromas and enhanced by alcoholic nuances attributed to cognitive interactions. Independent and non-correlated mouthfeel dimensions such as dry/silky and sticky, grainy, prickly or oily were also identified. Tannin activity was shown to be highly positively correlated to dry on the palate, and tannin concentration with both overall dry and dry on the palate. A significant partial least squares regression model showed that tannin concentration and activity (positive contribution) as well as pH values (negative) were good predictors of the mouthfeel dimension mainly related to dry and sticky terms. [ABSTRACT FROM AUTHOR]