Flowering Phenology Research Articles

Sympatric co-existence of two ecotypes of Impatiens noli-tangere (Balsaminaceae) with different morphology and flowering phenology.

In angiosperms, intraspecific variation of flowering phenology may affect reproductive isolation and, consequently, speciation. This study focused on Impatiens noli-tangere (Balsaminaceae), which is distributed over broad latitudinal and altitudinal ranges in Japan. We aimed to reveal the phenotypic mixture of two ecotypes of I. noli-tangere with different flowering phenology and morphological traits in a narrow contact zone. Previous studies have shown that I. noli-tangere has early- and late-flowering types. The early-flowering type makes buds in June and is distributed at high-elevation sites. The late-flowering type makes buds in July and is distributed at low-elevation sites. In this study, we analyzed the flowering phenology of individuals at an intermediate elevation site where the early- and late-flowering types grow in sympatry (contact zone). We found no individuals showing intermediate flowering phenology at the contact zone, and early- and late-flowering types were clearly distinguishable. We also found that the differences in many other phenotypic traits between the early- and late-flowering types were maintained, including the number of flowers produced (total number of chasmogamous and cleistogamous flowers), leaf morphology (aspect ratio, number of serrations), seed traits (aspect ratio), and flower bud formation positions on the plant. This study showed that these two flowering ecotypes maintain many different traits in sympatry.

Differences in flowering phenology and seed production of four morning glory (Ipomoea) species in Japan

AbstractThe spread of morning glory (Ipomoea spp.) in soybean fields in Japan has severely decreased soybean yield. Yet, current control measures do not control the proliferation of Ipomoea spp. As little is known about the flowering period and seed production among the different invading Ipomoea spp., it is challenging to create targeted control measures based on ecological characteristics. This study aimed to reveal the characteristics of the flowering phenology and seed production of four morning glory species, namely, Ipomoea coccinea L. (red morning glory), Ipomoea lacunosa L. (pitted morning glory), Ipomoea hederacea L. Jacq. var. integriuscula A. Gray (entireleaf morning glory), and Ipomoea triloba L. (three‐lobe morning glory). Between 2017 and 2019, the four selected study species were grown under similar conditions of soil quality, irrigation, and environmental influences and their flowering phenology and seed data were recorded. The flowering period ranged from 36 to 40 days, and the initial flowering of I. triloba was approximately 2 weeks later than the others. I. coccinea had the highest flowering number and seed production, followed by I. lacunosa, I. triloba, and I. hederacea var. integriuscula. The fruit setting rate of I. triloba decreased later in the reproductive stage but tended to increase as the daily mean temperature increased on each flowering day. Thus, we report that the flowering phenology and seed production differed greatly among the Ipomoea spp. These findings can provide crucial insights into designing targeted species‐specific control measures against the spread of Ipomoea spp. in Japan.

Genetic architecture of microhabitat adaptation traits in a pair of sympatric Primulina species

Exploring the genetic basis of adaptive divergence at fine spatial scales can broaden our basic understanding of evolution and how organisms may adapt to changing environments in the future. Cave-associated microhabitats provide a unique opportunity to gain insight into microgeographic adaptation. We studied the genetic architecture of microhabitat-related divergence in flower phenology and leaf traits between two sister species of Primulina, P. depressa and P. danxiaensis, which live in sympatry but occupy contrasting microhabitats. We identified 40 significant quantitative trait loci (QTLs) associated with the interspecific differences in these microhabitat adaptation traits. Flowering time was controlled by one major-effect and six minor-effect QTLs, while leaf traits were influenced by 9–12 QTLs of small to moderate effect. The genetic architecture of the flowering time and the specific leaf area was genetically independent of other traits. Our results suggest that microhabitat adaptation in sympatric populations of Primulina differs according to different traits, with leaf traits diverging with the accumulation of many small changes and flowering phenology being driven by major effect variance.

Muerte por reproducción sexual: El caso (sin resolver) de la floración de los bambúes

Bamboos belong to the grass family (or Poaceae). There are 1698 bamboo species distributed around the world in tropical, subtropical and temperate jungles and forests. In our country, there are five native genera that comprise 23 species. The least known characteristic of the woody bamboos is their flowering phenology. Four main types of flowering patterns have been described. However, the most interesting are those bamboo species that show a massive and cyclical flowering pattern, after a long period of vegetative growth. Such mass flowering events occur at roughly regular intervals and are followed by the death of the flowering individuals. The goal of this review is to provide an informative sample of the current knowledge of bamboo flowering, with an emphasis on the species native to Argentina. Currently, the approximate duration of the life cycle of most woody bamboo species in our country is known, based on a review of the collections of the most important national and international herbaria and an extensive bibliographic search. In most species, the average life cycles are multiples of 15-16years, with a 30-year cycle being the most common. The main hypotheses about the evolutionary forces that led bamboos to flower, seed and die synchronously are described. Likewise, environmental, genetic factors and the combination of both proposed as possible ‘causes’ of this atypical flowering pattern of bamboos are discussed. Finally, environmental and social consequences of this phenomenon are listed.

Impact of Chill and Heat Exposures under Diverse Climatic Conditions on Peach and Nectarine Flowering Phenology.

The present study aims to generalize cultivar-specific tree phenology responses to winter and spring temperatures and assess the effectiveness of the Tabuenca test and various chill and heat accumulation models in predicting bloom dates for a wide range of climatic conditions and years. To this end, we estimated the dates of rest completion and blooming and correlated them with observed bloom dates for 14 peach and nectarine cultivars that were evaluated in 11 locations across Europe (Greece, France, Italy, Romania and Spain), within the EUFRIN cultivar testing trial network. Chill accumulation varied considerably among the studied sites, ranging from 45 Chill Portions (CP) in Murcia-Torre Pacheco (Spain) to 97-98 CP in Cuneo (Italy) and Bucharest (Romania). Rest completion occurred latest or was not achieved at all for some cultivars in the southern sites in Murcia. Dormancy release happened earliest in Bucharest and Cuneo, sites where heat accumulation had a strong influence on the regulation of bloom time. Blooming occurred earliest in the moderately cold regions of Lleida (Spain) and Bellegarde (France), and 7-11 days later in the warmer locations of Rome (Italy) and Naoussa (Greece), suggesting that bloom timing is strongly influenced by delayed rest completion in these locations. The Dynamic Model resulted in both more homogeneous chill accumulation across years and better predictions of bloom dates, compared with the Utah, Positive Utah and Chilling Hours models. Prediction of bloom dates was less successful for low-chill cultivars than for medium- and high-chill cultivars. Further climatic and experimental data are needed to make estimates of the climatic needs of peach cultivars more robust and to generate reliable advice for enhancing the resilience of peach production under varying and changing climatic conditions.

Phenology of flowering and seed development of jernang rattan (Daemonorops spp.)

Abstract. Fridayanti N, Widajati E, Ilyas S, Budi SW, Palupi ER. 2023. Phenology of flowering and seed development of jernang rattan (Daemonorops spp.). Biodiversitas 24: 349-358. Jernang rattan has a high economic value due to its resin content in the exocarp, as the raw material of dyes, medicines, and cosmetics. The resin is highest in the immature fruit skin (exocarp); therefore, fruits are harvested before the seed is germinable. As a consequence, regeneration is very scarce, and the species is categorized as a rare plant. This research was aimed at investigating the flowering phenology and seed development of jernang rattan until they reach physiological maturity, when the viability and vigor are at their highest. The flowering phenology was observed based on Biologische Bundesanstalt Bundessortenamt and Chemische Industrie (BBCH), at the inflorescence stage, flowering stage, fruit development stage, and fruit ripening stage. The inflorescence development from flower bud until ready to bloom took 136.4 ±10.9 days for male plants and 141.6 ±16.4 days for female plants. The inflorescence of staminate flowers bloomed longer (29.4 ±2.7 days) than pistillate flowers (15.4 ± 4.0 days). Fruit abortion mostly occurs during the first six months of fruit development, coincides with the nuclear stage of endosperm, and the final seed set is 56%. It takes around 27 months of one reproduction cycle from the appearance of the inflorescence to seed maturity. The fruit reaches physiological maturity approximately at 22 MAA when the seed is of high viability and vigor, and harvesting at 22 MAA is best for seed production. It is recommended to set up a seed production area separated from the resin production area.

Flowering and leaf phenology are more variable and stronger associated to functional traits in herbaceous compared to tree species

Phenology of plants is changing rapidly due to global change which may have a large impact on many interactions in ecosystems. So far studies on the phenology of herbaceous species are largely underrepresented in phenology research which is mainly focused on trees and shrubs. In this study we investigated how different phenological stages during the annual life cycle differ between herbaceous species and trees and how they interact with functional traits. To answer these questions, we recorded multiple generative and vegetative phenological stages of 21 herbaceous and 19 tree species in the Botanical Garden of Jena in 2021. We further measured several functional traits for which relationships to flowering phenology have been found in comparable studies. We found evidence that the studied herbaceous species in comparison to the trees showed a larger variability in phenology indicated by a larger within compared to between growth form standard deviation for all phenological stages. This suggests that herbaceous species occupy more temporal niches to avoid competition. We also found that vegetative height is more strongly associated with the phenology of herbaceous species than with trees. For other functional traits, we were able to confirm known relationships between functional traits and phenology across both growth forms, whereby leaf dry matter content was particularly associated with phenological stages. This work is an explicit example of how useful phenological observations in botanical gardens can be to study and understand the complex relationships between plant phenology and functional traits. Further research is needed to investigate avenues to use widely available trait data to predict species-specific phenology.

Blooming plant species diversity patterns in two adjacent Costa Rican highland ecosystems.

The Costa Rican Paramo is a unique ecosystem with high levels of endemism that is geographically isolated from the Andean Paramos. Paramo ecosystems occur above Montane Forests, below the permanent snow level, and their vegetation differs notably from that of adjacent Montane Forests. We compared the composition and beta diversity of blooming plant species using phenological data from functional plant groups (i.e., insect-visited, bird-visited and insect + bird-visited plants) between a Paramo and a Montane Forest site in Costa Rica and analyzed seasonal changes in blooming plant diversity between the rainy and dry seasons. Species richness was higher in the Montane Forest for all plant categories, except for insect-visited plants, which was higher in the Paramo. Beta diversity and blooming plant composition differed between both ecosystems and seasons. Differences in species richness and beta diversity between Paramo and the adjacent Montane Forest are likely the result of dispersal events that occurred during the last glacial period and subsequent isolation, as climate turned to tropical conditions after the Pleistocene, and to stressful abiotic conditions in the Paramo ecosystem that limit species establishment. Differences in blooming plant composition between both ecosystems and seasons are likely attributed to differential effects of climatic cues triggering the flowering events in each ecosystem, but phylogenetic conservatism cannot be discarded. Analyses of species composition and richness based on flowering phenology data are useful to evaluate potential floral resources for floral visitors (insects and birds) and how these resources change spatially and temporarily in endangered ecosystems such as the Paramo.

The Effect Micro Climate on The Flowering Phenology of Forest Clove Plants (Zyzygium obtusifolium L)

Microclimate is one of the environmental factors that affect the growth, flowering and quality of clove flower production, including forest clove plants. This study aims to explain the effect of microclimate on the flowering phenology of forest clove plants and the length of the flowering phenoplast. The research lasted for 17 months, starting from January 2020 - May 2021. The field research was carried out on the island of Ambon, Maluku. The sampling location was determined using the purposive method. Measurement of temperature and relative humidity using a thermohydrometer, solar intensity was measured using a lux meter. Data analysis used principal component regression. The results showed that the length of the flowering phenology was 167.6 days. Microclimate parameters affect the flowering phenology of forest clove plants, R-square 0.93 and the correlation is very strong (R 0.95). Air temperature and intensity of sunlight, both between stands and below stands have a negative effect, meaning that with the influence of these three variables the flowering phenology takes place earlier. On the other hand, with the air humidity variable the effect is positive, meaning that the flowering phenology will be delayed. Air temperature is the variable that has the greatest influence on the flowering phenology of forest clove plants.

Individual flowering phenology shapes plant-pollinator interactions across ecological scales affecting plant reproduction.

The balance of pollination competition and facilitation among co-flowering plants and abiotic resource availability can modify plant species and individual reproduction. Floral resource succession and spatial heterogeneity modulate plant-pollinator interactions across ecological scales (individual plant, local assemblage, and interaction network of agroecological infrastructure across the farm). Intraspecific variation in flowering phenology can modulate the precise level of spatio-temporal heterogeneity in floral resources, pollen donor density, and pollinator interactions that a plant individual is exposed to, thereby affecting reproduction. We tested how abiotic resources and multi-scale plant-pollinator interactions affected individual plant seed set modulated by intraspecific variation in flowering phenology and spatio-temporal floral heterogeneity arising from agroecological infrastructure. We transplanted two focal insect-pollinated plant species (Cyanus segetum and Centaurea jacea, n=288) into agroecological infrastructure (10 sown wildflower and six legume-grass strips) across a farm-scale experiment (125 ha). We applied an individual-based phenologically explicit approach to match precisely the flowering period of plant individuals to the concomitant level of spatio-temporal heterogeneity in plant-pollinator interactions, potential pollen donors, floral resources, and abiotic conditions (temperature, water, and nitrogen). Individual plant attractiveness, assemblage floral density, and conspecific pollen donor density (C. jacea) improved seed set. Network linkage density increased focal species seed set and modified the effect of local assemblage richness and abundance on C. segetum. Mutual dependence on pollinators in networks increased C. segetum seed set, while C. jacea seed set was greatest where both specialization on pollinators and mutual dependence was high. Abiotic conditions were of little or no importance to seed set. Intra- and interspecific plant-pollinator interactions respond to spatio-temporal heterogeneity arising from agroecological management affecting wild plant species reproduction. The interplay of pollinator interactions within and between ecological scales affecting seed set implies a co-occurrence of pollinator-mediated facilitative and competitive interactions among plant species and individuals.

FLOWERING PHENOLOGY MAY SHAPE HYBRIDIZATION PATTERNS OF HAWTHORN (CRATAEGUS L.) SPECIES

Asynchronous flowering phenology is an important prezygotic barrier to hybridization, especially in the case of sympatric species, while the degree of overlap in flowering can influence hybridization odds and shift introgression. In our study, we investigated the flowering phenology of three sympatric Crataegus-species and their hybrids in Transylvania, Romania. C. laevigata flowered first at the end of April, followed by C. rhipidophylla and the hybrid taxa C. × subsphaerica and C.× media, C. × macrocarpa 8 days later, while C. monogyna flowered last, 3 days later. The parental species of the most frequent hybrid taxa C. × subsphaerica have been found to have the greatest overlap in their flowering, while hybrids of C. laevigata, which overlap narrowly in their flowering with the other two species, are rare. Interestingly, all three hybrid taxa overlapped almost perfectly in their flowering phenology with that of C. rhipidophylla, and except for C.× media, hybrid taxa are not intermediate in the timing of their flowering relative to their parents. Our results provide evidence that distribution patterns and frequency of Crataegus-hybrids in the landscape are at least partially shaped by the parental species’ overlap in flowering phenology, which influences hybridization odds and may shift introgression towards one of the parental species.

Environmental and genetic effects on phenotypic differences between Elaeocarpus photiniifolia (Elaeocarpaceae) ecotypes in dry and mesic habitats on a Japanese oceanic island

AbstractEcological speciation is a consequence of phenotypic and genetic differentiation, which is driven by divergent selection and reproductive isolation between different environments. In Elaeocarpus photiniifolia, a plant species endemic to the Bonin Islands, genetic differentiation between a shrub ecotype in dry habitats and a tree ecotype in mesic habitats occurs in the Chichijima Island Group, while gene flow between the ecotypes and migration between the habitats are feasible. To clarify environmental and genetic effects on traits different between the ecotypes, we examined the soil moisture content, nuclear microsatellite genotypes, plant height, and flowering phenology in dry and mesic habitats in two areas on Chichijima Island. The soil moisture content decreased from June to July in both areas and tended to be lower in dry habitats than in mesic habitats in July. Genetic structure indicated not only genetic differentiation between the ecotypes but also admixture between them and migration between the habitats. Both environmental and genetic effects were detected in plant height and flowering phenology: lower height and earlier flowering of the shrub ecotype in the dry habitats, indicating phenotypic plasticity in response to drought, and genetic variation between ecotypes in both traits. These findings indicate that phenotypic plasticity in response to different environments results in different flowering phenology, which facilitates reproductive isolation and genetic differentiation, leading to genetic variation in adaptive traits associated with the environments.

Flowering Phenology of Selected Elepidote Rhododendron L. Taxa

This study aims to evaluate the flowering phenology of selected 95 Elepidote Rhododendron taxa. The flowering period was assessed, distinguishing ten developmental stages. Flowering was observed every three days. The comparative scale prepared indicates the exact succession of bloom of taxa. Flowering of 95 taxa lasted from the end of April to the second half of June. The flowering period of individual cultivars ranged from 2 to 9 weeks. The flowering time of cultivars belonging to the same species was mostly similar. The term of cultivars flowering was in the following tendency order: R. caucasicum–R. wardii–R. forestii–R. williamsianum–R. catawbiense–R. ponticum.

Phenology and morphology of the invasive legume Lupinus polyphyllus along a latitudinal gradient in Europe

Plant phenology, i. e. the timing of life cycle events, is related to individual fitness and species distribution ranges. Temperature is one of the most important drivers of plant phenology together with day length. The adaptation of their phenology may be important for the success of invasive plant species. The present study aims at understanding how the performance and the phenology of the invasive legume Lupinus polyphyllus vary with latitude. We sampled data across a >2000 km latitudinal gradient from Central to Northern Europe. We quantified variation in phenology of flowering and fruiting of L. polyphyllus using >1600 digital photos of inflorescences from 220 individual plants observed weekly at 22 sites. The day of the year at which different phenological phases were reached, increased 1.3–1.8 days per degree latitude, whereas the growing degree days (gdd) required for these phenological phases decreased 5–16 gdd per degree latitude. However, this difference disappeared, when the day length of each day included in the calculation of gdd was considered. The day of the year of the earliest and the latest climatic zone to reach any of the three studied phenological phases differed by 23–30 days and temperature requirements to reach these stages differed between 62 and 236 gdd. Probably, the invasion of this species will further increase in the northern part of Europe over the next decades due to climate warming. For invasive species control, our results suggest that in countries with a large latitudinal extent, the mowing date should shift by ca. one week per 500 km at sites with similar elevations.

Genome-wide association study of 23 flowering phenology traits and 4 floral agronomic traits in tree peony (Paeonia section Moutan DC.) reveals five genes known to regulate flowering time.

Tree peony is a unique traditional flower in China, with large, fragrant, and colorful flowers. However, a relatively short and concentrated flowering period limits the applications and production of tree peony. A genome-wide association study (GWAS) was conducted to accelerate molecular breeding for the improvement of flowering phenology traits and ornamental phenotypes in tree peony. A diverse panel of 451 tree peony accessions was phenotyped for 23 flowering phenology traits and 4 floral agronomic traits over 3 years. Genotyping by sequencing (GBS) was used to obtain a large number of genome-wide single-nucleotide polymorphisms (SNPs) (107 050) for the panel genotypes, and 1047 candidate genes were identified by association mapping. Eighty-two related genes were observed during at least 2 years for flowering, and seven SNPs repeatedly identified for multiple flowering phenology traits over multiple years were highly significantly associated with five genes known to regulate flowering time. We validated the temporal expression profiles of these candidate genes and highlighted their possible roles in the regulation of flower bud differentiation and flowering time in tree peony. This study shows that GWAS based on GBS can be used to identify the genetic determinants of complex traits in tree peony. The results expand our understanding of flowering time control in perennial woody plants. Identification of markers closely related to these flowering phenology traits can be used in tree peony breeding programs for important agronomic traits.

Airborne cues accelerate flowering and promote photosynthesis in Brassica rapa

Abstract Volatile cues can induce and/or prime plant defences, but it is less well known if plants also respond by altering growth and reproduction‐related parameters. Here, we evaluated whether plant volatile cues can elicit changes in growth, flower production, net photosynthesis rate and defences in receiver plants and whether those responses are similar to those elicited in response to direct herbivore‐feeding. Our results demonstrate that exposure to volatiles emitted from damaged neighbours accelerated the time to first flowering, increased the number of flowers produced and the net photosynthesis rate, but did not alter the fresh harvested plant biomass and volatile defences, compared to non‐exposed plants. Earlier flowering was also observed for plants exposed to volatiles from undamaged plants. These responses differed from those of plants exposed to actual herbivore‐feeding for which feeding enhanced net photosynthesis rate but reduced growth and had no effect on reproduction and defence in response to subsequent herbivory. Synthesis. These findings document that plant airborne cues can influence floral traits of receiver plants. In particular, the flower phenology is modulated, and photosynthesis is enhanced, suggesting that carbon allocation could be directed toward reproduction.

Short Communication: Correlation of flowering phenology and heat unit of forest cloves (Syzygium obtusifolium) at different elevations in Maluku Province, Indonesia

Abstract. Kamsurya MY, Ala A, Musa Y, Rafiuddin. 2022. Short Communication: Correlation of flowering phenology and heat unit of forest cloves (Syzygium obtusifolium) at different elevations in Maluku Province, Indonesia. Biodiversitas 23: 5593-5599. The phenology and heat unit of the forest clove (Syzygium obtusifolium L.) are important parameters for the efficient maintenance of this plant. This study aimed to describe phenological flowering stages (PFS) and calculate growing degree days for different PFS, which will have a big impact on crop management and understanding the impact of climate variables on crucial phenological events. The research was conducted in Ambon, Maluku Province, Indonesia, for 16 months, from January 2020 to May 2021. Five sample points at different elevations were determined purposively, i.e: Halasi (6 m above sea level (m asl)), Tibang (11 m asl), Oli (125 m asl), Wanat (175 m asl), and Telaga Kodok (214 m asl). The phenology of flowering is separated into 6 stages: the flowering primordia, the appearance of the flower stalk, the perfect flower stalk, the appearance of the flower bud, the flower is fully formed, and the flower starts to bloom. The results showed that the phenological cycle of the forest clove plant was flowering periodically for 365 days. The average temperature of PFS (29oC) in Halasi was higher compared to other locations. It indicates that the lower the altitude, the faster the flowering period. This study found significant correlations between altitude and PFS, except flower stalks appear and flowers will appear. The phenology of clove plants is influenced by the accumulation of heat units, with the highest heat unit value in the flowers start to bloom stage, ranging from 2,983.23 dayso (Telaga Kodok) to 3,128.84 dayso (Halasi). As elevation increases, the number of heat units decreases, so the PFS is delayed. The primordial phase in Halasi appears in August-September while at Telaga Kodok in December.

Warming reduced flowering synchrony and extended community flowering season in an alpine meadow on the Tibetan Plateau.

The timing of phenological events is highly sensitive to climate change, and may influence ecosystem structure and function. Although changes in flowering phenology among species under climate change have been reported widely, how species-specific shifts will affect phenological synchrony and community-level phenology patterns remains unclear. We conducted a manipulative experiment of warming and precipitation addition and reduction to explore how climate change affected flowering phenology at the species and community levels in an alpine meadow on the eastern Tibetan Plateau. We found that warming advanced the first and last flowering times differently and with no consistent shifts in flowering duration among species, resulting in the entire flowering period of species emerging earlier in the growing season. Early-flowering species were more sensitive to warming than mid- and late-flowering species, thereby reducing flowering synchrony among species and extending the community-level flowering season. However, precipitation and its interactions with warming had no significant effects on flowering phenology. Our results suggest that temperature regulates flowering phenology from the species to community levels in this alpine meadow community, yet how species shifted their flowering timing and duration in response to warming varied. This species-level divergence may reshape flowering phenology in this alpine plant community. Decreasing flowering synchrony among species and the extension of community-level flowering seasons under warming may alter future trophic interactions, with cascading consequences to community and ecosystem function.

Genetic studies on continuous flowering in woody plant Osmanthus fragrans.

Continuous flowering is a key horticultural trait in ornamental plants, whereas the specific molecular regulation mechanism remains largely unknown. In sweet osmanthus (Osmanthus fragrans Lour.), plants based on their flowering characteristics are divided into once-flowering (OF) habit and continuous flowering (CF) habit. Here, we first described the flowering phenology shifts of OF and CF habits in sweet osmanthus through paraffin section and microscope assay. Phenotypic characterization showed that CF plants had constant new shoot growth, floral transition, and blooming for 1 year, which might lead to a continuous flowering trait. We performed the transcriptome sequencing of OF and CF sweet osmanthus and analyzed the transcriptional activity of flowering-related genes. Among the genes, three floral integrators, OfFT, OfTFL1, and OfBFT, had a differential expression during the floral transition process in OF and CF habits. The expression patterns of the three genes in 1 year were revealed. The results suggested that their accumulations corresponded to the new shoots occurring and the floral transition process. Function studies suggested that OfFT acted as a flowering activator, whereas OfBFT was a flowering inhibitor. Yeast one-hybrid assay indicated that OfSPL8 was a common upstream transcription factor of OfFT and OfBFT, suggesting the vital role of OfSPL8 in continuous flowering regulation. These results provide a novel insight into the molecular mechanism of continuous flowering.

A regionally coherent ecological fingerprint of climate change, evidenced from natural history collections.

Climate change has dramatic impacts on ecological systems, affecting a range of ecological factors including phenology, species abundance, diversity, and distribution. The breadth of climate change impacts on ecological systems leads to the occurrence of fingerprints of climate change. However, climate fingerprints are usually identified across broad geographical scales and are potentially influenced by publication biases. In this study, we used natural history collections spanning over 250 years, to quantify a range of ecological responses to climate change, including phenology, abundance, diversity, and distributions, across a range of taxa, including vertebrates, invertebrates, plants, and fungi, within a single region, Central Norway. We tested the hypotheses that ecological responses to climate change are apparent and coherent at a regional scale, that longer time series show stronger trends over time and in relation to temperature, and that ecological responses change in trajectory at the same time as shifts in temperature. We identified a clear regional coherence in climate signal, with decreasing abundances of limnic zooplankton (on average by 7691 individuals m-3°C-1) and boreal forest breeding birds (on average by 1.94 territories km-2°C-1), and earlier plant flowering phenology (on average 2 days °C-1) for every degree of temperature increase. In contrast, regional-scale species distributions and species diversity were largely stable. Surprisingly, the effect size of ecological response did not increase with study duration, and shifts in responses did not occur at the same time as shifts in temperature. This may be as the long-term studies include both periods of warming and temperature stability, and that ecological responses lag behind warming. Our findings demonstrate a regional climate fingerprint across a long timescale. We contend that natural history collections provide a unique window on a broad spectrum of ecological responses at timescales beyond most ecological monitoring programs. Natural history collections are thus an essential source for long-term ecological research.