Abstract Background and Aims In species with specialized pollination, floral traits are expected to be relatively invariant and decoupled from the phenotypic variation affecting vegetative traits.
This study investigates photoperiodic responses in natural populations of Arabidopsis thaliana from high northern latitudes and their significance for local adaptation.
Thirty lineages from ten local A. We studied relationships between variation in photoperiodic sensitivity of flowering time, altitude, and climatic factors associated with the sites of origin.
We found that variation in response to photoperiod is significantly correlated with altitude and climatic variables associated with the sites of origin of the populations.
Populations originating from lower altitudes showed stronger photoperiodic sensitivity than populations from higher altitudes. Our results indicate that the altitudinal climatic gradient generates clinal variation in adaptive traits in A.
Introduction Photoperiod is an environmental cue that many organisms use to regulate seasonal changes in behavior, migration, and reproduction Kardailsky et al.
At temperate and subarctic latitudes, photoperiod, light quality, and temperature are major environmental signals that plants sense in order to synchronize their flowering time with the changing seasons Bradshaw et al. Variation in flowering time of plants contributes to local adaptation to different growth conditions, and hence clinal variation in flowering time is believed to be a sign of adaptive evolution Endler, Arabidopsis thaliana is a facultative long-day plant and flowering time in response to photoperiod has been studied extensively Lee and Amasino, ; Onouchi and Coupland, ; Simpson and Dean, ; El-Assal et al.
Since it is crucial for populations originating from higher northern latitudes to reproduce at a proper time of the year, one would expect that they are more sensitive to changes in photoperiod than populations from lower latitudes.
However, contradictory findings have been reported. Moreover, Samis et al. However, latitudinal clines in flowering time Stinchcombe et al. On a continental-wide scale, essential climatic factors vary with latitude and therefore latitudinal coordinates may be a significant proxy for climatic factors such as temperature and photoperiod.
However, on smaller geographic scales, transects are present at the same latitude, e. In these cases, latitude is not a suitable proxy for ecologically important environmental cues.
Furthermore, an earlier study in our group found that altitude, and not latitude, is a better proxy for environmental cues at the northernmost range of distribution of a species, like A. Due to the influence of the North Atlantic Current, the temperature fluctuates during the winter season in coastal and low-altitude regions of Norway and the precipitation comes not only in the form of snow but more often in the form of rain, sleet and hail.
Moderate winter temperatures, and increased winter and yearly precipitation characterize these locations.
On the contrary, in regions at higher altitudes, stable low temperatures during the winter season and moderate winter and yearly precipitation result in a long lasting snow cover. In the same way as environmental cues, varying across broad geographic regions, will impose natural selection on flowering time Engelmann and Purugganan, ; Hall and Willis, ; Verhoeven et al.
The photoperiod that plants experience during the growing season at higher northern latitudes depends not only on latitude of origin but also on the duration of the snow cover, determined by temperature and precipitation during autumn and winter.
In the present study, we used lineages derived from high and low altitude local populations of A. · It is possible that a relationship exists between flower size and the development of fruits, and that those larger flowers presented smaller concentration of some nutrients due to dilution effect.
That would explain the observed negative ashio-midori.com · Moreover, the difference in the total number of floral organs between ‘Malmaison’ and ‘St Anne's’ also suggests a difference in floral meristem size.
Floral Morphogenesis at Early Stages in ‘Malmaison’ and ‘St Anne's’ashio-midori.com?id=/ashio-midori.com Abstract. Over three years the flowering phenology of individuals of Lotus corniculatus has been studied in relation to fruit set and seed predation to determine the relationships between four components of flowering time, plant size and reproductive success.
· Reporting selection differentials (which measure direct and indirect selection through correlated traits) acting on flowering time and duration (and possibly flower number or display size, e.g.
Sandring & Ågren, ), along with the correlation between them, is ashio-midori.com Experimental manipulations of flowers provide powerful support for pollinator-mediated selection on flower size and other floral characteristics through both male (pollen transfer) and female (fruit and seed set) components of reproductive success (Dudash et al., ; Fenster et al., ; Galen and Cuba, ; Parachnowitsch and Kessler, ; Sandring and Ågren, ).
Investigation of the Correlation between Flower Size to Size of Reproduction Organs and Concentration of Anthocyanin.
Abstract: In this study, the relationship of the flower size in comparison to the ovary mass, stamen mass, and the anthocyanin concentration was an ashio-midori.com