Feral rye is an agricultural and ruderal weed of the western United States. We investigated how it has phenotypically diverged from its cultivated ancestor, domesticated cereal rye, and across its range since the introduction of its progenitor. Vegetative growth, flowering phenology, and reproductive characters of feral populations from across a 13° range in latitude in the northwestern United States were compared to that of rye cultivars under both vernalized (cold-treated) and nonvernalized conditions. Feral populations as a whole had smaller seeds, thinner culms, and a delay in flowering relative to cultivars, regardless of cold treatment. Vernalized feral populations from northern latitudes (northern California and eastern Washington) produced more, but smaller leaves and more tillers than both vernalized rye cultivars and southern California feral populations. Northern feral populations also flowered significantly later, irrespective of vernalization treatment. We conclude that feral rye is phenotypically distinct from domesticated cereal rye and that feral populations have diverged regionally from one another. Reproductive isolation from domesticated rye, due both to the loss in popularity of the crop and to phenological shifts in feral rye relative to cultivars, may be contributing to the rapid evolution of this weed away from its domesticated ancestor in less than 120 yr since its introduction.

In mammals, short photoperiod is associated with high depression- and anxiety-like behaviours with low levels of the brain serotonin and its precursor tryptophan (Trp). Because the brain Trp levels are regulated by its ratio to large neutral amino acids (Trp:LNAA) in circulation, this study elucidated whether diets of various protein sources that contain different Trp:LNAA affect depression- and anxiety-like behaviours in C57BL/6J mice under short-day conditions (SD). In the control mice on a casein diet, time spent in the central area in the open field test (OFT) was lower in the mice under SD than in those under long-day conditions (LD), indicating that SD exposure induces anxiety-like behaviour. The SD-induced anxiety-like behaviour was countered by an α-lactalbumin diet given under SD. In the mice that were on a gluten diet before transition to SD, the time spent in the central area in the OFT under SD was higher than that in the SD control mice. Alternatively, mice that ingested soya protein before the transition to SD had lower immobility in the forced swim test, a depression-like behaviour, compared with the SD control. Analysis of Trp:LNAA revealed lower Trp:LNAA in the SD control compared with the LD control, which was counteracted by an α-lactalbumin diet under SD. Furthermore, mice on gluten or soya protein diets before transition to SD exhibited high Trp:LNAA levels in plasma under SD. In conclusion, ingestion of specific proteins at different times relative to photoperiodic transition may modulate anxiety- and/or depression-like behaviours, partially through changes in plasma Trp:LNAA.

The trajectory of retinal projections and the location of retinorecipient nuclei in the quail brain was examined after application of horseradish peroxidase (HRP) either to the cut end of the optic nerve or following intraocular injection of HRP. Retinal projections to the hypothalamus, dorsalateral anterior thalamus (rostralateral part, magnocellular part, and lateral part), lateral anterior thalamus, lateroventral geniculate nucleus, lateral geniculate intercalated nuclei (rostral and caudal parts), ventrolateral thalamus, superficial synencephalic nucleus, external nucleus, tectal gray, diffuse pretectal area, pretectal optic area, ectomammillary nucleus, and optic tectum were revealed. Retinal projections observed in quail were compared with results obtained in other avian species and considered in relation to possible anatomic pathways underlying photoperiodism and circadian rhythms.

Biological rhythms are ubiquitous in eukaryotes, and the best understood of these occur with a period of approximately a day – circadian rhythms. Such rhythms persist even when the organism is placed under constant conditions, with a period that is close, but not exactly equal, to 24 h, and are driven by an endogenous timer – one of the many ‘biological clocks’. In plants, research into circadian rhythms has been driven forward by genetic experiments using Arabidopsis. Higher plant genomes include a particularly large number of genes involved in metabolism, and circadian rhythms may well provide the necessary coordination for the control of these – for example, around the diurnal rhythm of photosynthesis – to suit changing developmental or environmental conditions. The endogenous timer must be flexible enough to support these requirements. Current research supports this notion most strongly for the input pathway, in which multiple photoreceptors have been shown to mediate light input to the clock. Both input and output components are now related to putative circadian oscillator mechanisms by sequence homology or by experimental observation. It appears that the pathways linking some domains of the basic clock model may be very short indeed, or the mechanisms of these domains may overlap. Components of the first plant circadian output pathway to be identified unequivocally will help to determine exactly how many output pathways control the various phases of overt rhythms in plants.