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Summary Vernalization and photoperiod pathways converging at FT1 control the transition to flowering in wheat. Here, we identified a gain‐of‐function mutation in FT‐D1 that results in earlier heading date (HD), and shorter plant height and spike length in the gamma ray‐induced eh1 wheat mutant. Knockout of the wild‐type and overexpression of the mutated FT‐D1 indicate that both alleles are functional to affect HD and plant height. Protein interaction assays demonstrated that the frameshift mutation in FT‐D1eh1 exon 3 led to gain‐of‐function interactions with 14‐3‐3A and FDL6, thereby enabling the formation of florigen activation complex (FAC) and consequently activating a flowering‐related transcriptomic programme. This mutation did not affect FT‐D1eh1 interactions with TaNaKR5 or TaFTIP7, both of which could modulate HD, potentially via mediating FT‐D1 translocation to the shoot apical meristem. Furthermore, the ‘Segment B’ external loop is essential for FT‐D1 interaction with FDL6, while residue Y85 is required for interactions with TaNaKR5 and TaFTIP7. Finally, the flowering regulatory hub gene, ELF5, was identified as the FT‐D1 regulatory target. This study illustrates FT‐D1 function in determining wheat HD with a suite of interaction partners and provides genetic resources for tuning HD in elite wheat lines. [ABSTRACT FROM AUTHOR]

Long-term exposure to cold during the winter season, so-called vernalization, triggers the transition from the vegetative to the reproductive stage in many biennial and perennial plants. In the last decades, intensive researches have revealed the molecular mechanisms underlying this phenomenon, particularly using Arabidopsis model plant. Most Brassicaceae family plants, including the Arabidopsis, require vernalization for floral transition. Brassicaceae family plants can be classified into two groups: seed vernalization responsive type and plant vernalization responsive type. Cabbage belongs to plant vernalization responsive type. Molecular details on plant vernalization responsive trait of cabbage on vernalization are still poorly understood. In this study, we conducted a transcriptomic analysis of the cabbage inbred line 'BN2348' in response to vernalization. Similar to the case of Arabidopsis, two VIN3 homologs (BoVIN3.C3 and BoVIN3.C2) were highly induced by the exposure to long-term cold in B. oleracea. Our transcriptome analysis identified that two FT homologs (BoFT.C2 and BoFT.C6) and three SOC1 homologs (BoSOC1.1.C4, BoSOC1.2.C4, and BoSOC1.C3) were functioning for the regulation of floral transition in B. oleracea. In addition, by phylogenic and syntenic analyses, a total of five FLC homologs, named BoFLC1.a, BoFLC1.b, BoFLC2, BoFLC3, and BoFLC5, were identified in the genome of B. oleracea. Transcriptomic analysis indicated that these genes could be grouped into vernalization-responsive (BoFLC2 and BoFLC3) and vernalization-insensitive genes (BoFLC1.a, BoFLC1.b, and BoFLC5). As green plant vernalization type, it might suggest the existence of vernalization-insensitive BoFLC homologs in young seedlings might be the reason why cabbage exhibits longer exposure of cold compared to seed vernalization type plants such as Chinese cabbage and Arabidopsis. These findings improve our understanding of the molecular dynamics underlying floral transition in cabbage plants. [ABSTRACT FROM AUTHOR]

Background: White lupin (Lupinus albus L.) is a high-protein Old World grain legume with remarkable food and feed production interest. It is sown in autumn or early spring, depending on the local agroclimatic conditions. This study aimed to identify allelic variants associated with vernalization responsiveness, in order to improve our knowledge of legume flowering regulatory pathways and develop molecular selection tools for the desired phenology as required for current breeding and adaptation to the changing climate. Results: Some 120 white lupin accessions originating from a wide range of environments of Europe, Africa, and Asia were phenotyped under field conditions in three environments with different intensities of vernalization, namely, a Mediterranean and a subcontinental climate sites of Italy under autumn sowing, and a suboceanic climate site of France under spring sowing. Two hundred sixty-two individual genotypes extracted from them were phenotyped in a greenhouse under long-day photoperiod without vernalization. Phenology data, and marker data generated by Diversity Arrays Technology sequencing (DArT-seq) and by PCR-based screening targeting published quantitative trait loci (QTLs) from linkage map and newly identified insertion/deletion polymorphisms in the promoter region of the FLOWERING LOCUS T homolog, LalbFTc1 gene (Lalb_Chr14g0364281), were subjected to a genome-wide association study (GWAS). Population structure followed differences in phenology and isolation by distance pattern. The GWAS highlighted numerous loci significantly associated with flowering time, including four LalbFTc1 gene promoter deletions: 2388 bp and 2126 bp deletions at the 5' end, a 264 bp deletion in the middle and a 28 bp deletion at the 3' end of the promoter. Besides LalbFTc1 deletions, this set contained DArT-seq markers that matched previously published major QTLs in chromosomes Lalb_Chr02, Lalb_Chr13 and Lalb_Chr16, and newly discovered QTLs in other chromosomes. Conclusions: This study highlighted novel QTLs for flowering time and validated those already published, thereby providing novel evidence on the convergence of FTc1 gene functional evolution into the vernalization pathway in Old World lupin species. Moreover, this research provided the set of loci specific for extreme phenotypes (the earliest or the latest) awaiting further implementation in marker-assisted selection for spring- or winter sowing. [ABSTRACT FROM AUTHOR]

Background and Aims The timing of flowering onset is often correlated with latitude, indicative of climatic gradients. Flowering onset in temperate species commonly requires exposure to cold temperatures, known as vernalization. Hence, population differentiation of flowering onset with latitude might reflect adaptation to the local climatic conditions experienced by populations. Methods Within its western range, seeds from Linum bienne populations (the wild relative of cultivated Linum usitatissimum) were used to describe the latitudinal differentiation of flowering onset to determine its association with the local climate of the population. A vernalization experiment including different crop cultivars was used to determine how vernalization accelerates flowering onset, in addition to the vernalization sensitivity response among populations and cultivars. Additionally, genetic differentiation of L. bienne populations along the latitudinal range was scrutinized using microsatellite markers. Key Results Flowering onset varied with latitude of origin, with southern populations flowering earlier than their northern counterparts. Vernalization reduced the number of days to flowering onset, but vernalization sensitivity was greater in northern populations compared with southern ones. Conversely, vernalization delayed flowering onset in the crop, exhibiting less variation in sensitivity. In L. bienne , both flowering onset and vernalization sensitivity were better predicted by the local climate of the population than by latitude itself. Microsatellite data unveiled genetic differentiation of populations, forming two groups geographically partitioned along latitude. Conclusions The consistent finding of latitudinal variation across experiments suggests that both flowering onset and vernalization sensitivity in L. bienne populations are under genetic regulation and might depend on climatic cues at the place of origin. The association with climatic gradients along latitude suggests that the climate experienced locally drives population differentiation of the flowering onset and vernalization sensitivity patterns. The genetic population structure suggests that past population history could have influenced the flowering initiation patterns detected, which deserves further work. [ABSTRACT FROM AUTHOR]

Bolting and flowering of vegetables are induced by vernalization in their early growth stage. This phenomenon is called premature bolting, and it has caused massive losses in production of vegetables such as cabbage, celery, carrot, radish, and spinach, etc. This review aimed to summarize studies on bolting and flowering pathways, physiological and biochemical changes, and underlined molecular mechanisms of various vegetable crop bolting involving genome and transcriptome analysis, and its association with vegetable breeding. This review could provide basic knowledge to carry out research on vegetable genetics and breeding and vegetable cultivation. [ABSTRACT FROM AUTHOR]

Abstract Background White lupin (Lupinus albus L.) is a high-protein Old World grain legume with remarkable food and feed production interest. It is sown in autumn or early spring, depending on the local agroclimatic conditions. This study aimed to identify allelic variants associated with vernalization responsiveness, in order to improve our knowledge of legume flowering regulatory pathways and develop molecular selection tools for the desired phenology as required for current breeding and adaptation to the changing climate. Results Some 120 white lupin accessions originating from a wide range of environments of Europe, Africa, and Asia were phenotyped under field conditions in three environments with different intensities of vernalization, namely, a Mediterranean and a subcontinental climate sites of Italy under autumn sowing, and a suboceanic climate site of France under spring sowing. Two hundred sixty-two individual genotypes extracted from them were phenotyped in a greenhouse under long-day photoperiod without vernalization. Phenology data, and marker data generated by Diversity Arrays Technology sequencing (DArT-seq) and by PCR-based screening targeting published quantitative trait loci (QTLs) from linkage map and newly identified insertion/deletion polymorphisms in the promoter region of the FLOWERING LOCUS T homolog, LalbFTc1 gene (Lalb_Chr14g0364281), were subjected to a genome-wide association study (GWAS). Population structure followed differences in phenology and isolation by distance pattern. The GWAS highlighted numerous loci significantly associated with flowering time, including four LalbFTc1 gene promoter deletions: 2388 bp and 2126 bp deletions at the 5’ end, a 264 bp deletion in the middle and a 28 bp deletion at the 3’ end of the promoter. Besides LalbFTc1 deletions, this set contained DArT-seq markers that matched previously published major QTLs in chromosomes Lalb_Chr02, Lalb_Chr13 and Lalb_Chr16, and newly discovered QTLs in other chromosomes. Conclusions This study highlighted novel QTLs for flowering time and validated those already published, thereby providing novel evidence on the convergence of FTc1 gene functional evolution into the vernalization pathway in Old World lupin species. Moreover, this research provided the set of loci specific for extreme phenotypes (the earliest or the latest) awaiting further implementation in marker-assisted selection for spring- or winter sowing.

Abstract Background Winter wheat undergoes vernalization, a process activated by prolonged exposure to low temperatures. During this phase, flowering signals are generated and transported to the apical meristems, stimulating the transition to the inflorescence meristem while inhibiting tiller bud elongation. Although some vernalization genes have been identified, the key cis-regulatory elements and precise mechanisms governing this process in wheat remain largely unknown. Results In this study, we construct extensive epigenomic and transcriptomic profiling across multiple tissues—leaf, axillary bud, and shoot apex—during the vernalization of winter wheat. Epigenetic modifications play a crucial role in eliciting tissue-specific responses and sub-genome-divergent expressions during vernalization. Notably, we observe that H3K27me3 primarily regulates vernalization-induced genes and has limited influence on vernalization-repressed genes. The integration of these datasets enables the identification of 10,600 putative vernalization-related regulatory elements including distal accessible chromatin regions (ACRs) situated 30Kb upstream of VRN3, contributing to the construction of a comprehensive regulatory network. Furthermore, we discover that TaSPL7/15, integral components of the aging-related flowering pathway, interact with the VRN1 promoter and VRN3 distal regulatory elements. These interactions finely regulate their expressions, consequently impacting the vernalization process and flowering. Conclusions Our study offers critical insights into wheat vernalization’s epigenomic dynamics and identifies the putative regulatory elements crucial for developing wheat germplasm with varied vernalization characteristics. It also establishes a vernalization-related transcriptional network, and uncovers that TaSPL7/15 from the aging pathway participates in vernalization by directly binding to the VRN1 promoter and VRN3 distal regulatory elements.

Properly regulated flowering time is pivotal for successful plant reproduction. The floral transition from vegetative growth to reproductive growth is regulated by a complex gene regulatory network that integrates environmental signals and internal conditions to ensure that flowering takes place under favorable conditions. Brassica rapa is a diploid Cruciferae species that includes several varieties that are cultivated as vegetable or oil crops. Flowering time is one of the most important agricultural traits of B. rapa crops because of its influence on yield and quality. The transition to flowering in B. rapa is regulated by several environmental and developmental cues, which are perceived by several signaling pathways, including the vernalization pathway, the autonomous pathway, the circadian clock, the thermosensory pathway, and gibberellin (GA) signaling. These signals are integrated to control the expression of floral integrators BrFTs and BrSOC1s to regulate flowering. In this review, we summarized current research advances on the molecular mechanisms that govern flowering time regulation in B. rapa and compare this to what is known in Arabidopsis.

Vernalization is necessary for winter wheat to flower. However, it is unclear whether vernalization is also required for spring wheat, which is frequently sown in fall, and what molecular mechanisms underlie the vernalization response in wheat varieties. In this study, we examined the molecular mechanisms that regulate vernalization response in winter and spring wheat varieties. For this purpose, we determined how major vernalization genes (VRN1, VRN2, and VRN3) respond to vernalization in these varieties and whether modifications to histones play a role in changes in gene expression. We also identified genes that are differentially regulated in response to vernalization in winter and spring wheat varieties. We found that in winter wheat, but not in spring wheat, VRN1 expression decreases when returned to warm temperature following vernalization. This finding may be associated with differences between spring and winter wheat in the levels of tri-methylation of lysine 27 on histone H3 (H3K27me3) and tri-methylation of lysine 4 on histone H3 (H3K4me3) at the VRN1 gene. Analysis of winter wheat transcriptomes before and after vernalization revealed that vernalization influences the expression of several genes, including those involved in leucine catabolism, cysteine biosynthesis, and flavonoid biosynthesis. These findings provide new candidates for further study on the mechanism of vernalization regulation in wheat.

SUMMARY: Histone 2B ubiquitination (H2Bub) and trimethylation of H3 at lysine 4 (H3K4me3) are associated with transcription activation. However, the function of these modifications in transcription in plants remains largely unknown. Here, we report that coordination of H2Bub and H3K4me3 deposition with the binding of the RNA polymerase‐associated factor VERNALIZATION INDEPENDENCE2 (VIP2) to FLOWERING LOCUS C (FLC) modulates flowering time in Arabidopsis. We found that RING domain protein HISTONE MONOUBIQUITINATION1 (HUB1) and HUB2 (we refer as HUB1/2), which are responsible for H2Bub, interact with ARABIDOPSIS TRITHORAX1 (ATX1), which is required for H3K4me3 deposition, to promote the transcription of FLC and repress the flowering time. The atx1‐2 hub1‐10 hub2‐2 triple mutant in FRIGIDIA (FRI) background displayed early flowering like FRI hub1‐10 hub2‐2 and overexpression of ATX1 failed to rescue the early flowering phenotype of hub1‐10 hub2‐2. Mutations in HUB1 and HUB2 reduced the ATX1 enrichment at FLC, indicating that HUB1 and HUB2 are required for ATX1 recruitment and H3K4me3 deposition at FLC. We also found that the VIP2 directly binds to HUB1, HUB2, and ATX1 and that loss of VIP2 in FRI hub1‐10 hub2‐2 and FRI atx1‐2 plants resulted in early flowering like that observed in FRI vip2‐10. Loss of function of HUB2 and ATX1 impaired VIP2 enrichment at FLC, and reduced the transcription initiation and elongation of FLC. In addition, mutations in VIP2 reduced HUB1 and ATX1 enrichment and H2Bub and H3K4me3 levels at FLC. Together, our findings revealed that HUB1/2, ATX1, and VIP2 coordinately modulate H2Bub and H3K4me3 deposition, FLC transcription, and flowering time. Significance Statement: Flowering at appropriate time is a critical trait for environmental adaption for plant pollination, and seed production. Here, we show that H2Bub, H3K4me3, and VIP2 coordinately modulate the transcription process and flowering time in Arabidopsis. [ABSTRACT FROM AUTHOR]

Wheat is a major food crop that plays a crucial role in the human diet. Various breeding technologies have been developed and refined to meet the increasing global wheat demand. Several studies have suggested breeding strategies that combine generation acceleration systems and molecular breeding methods to maximize breeding efficiency. However, real-world examples demonstrating the effective utilization of these strategies in breeding programs are lacking. In this study, we designed and demonstrated a synergized breeding strategy (SBS) that combines rapid and efficient breeding techniques, including speed breeding, speed vernalization, phenotypic selection, backcrossing, and marker-assisted selection. These breeding techniques were tailored to the specific characteristics of the breeding materials and objectives. Using the SBS approach, from artificial crossing to the initial observed yield trial under field conditions only took 3.5 years, resulting in a 53% reduction in the time required to develop a BC2 nearisogenic line (NIL) and achieving a higher recurrent genome recovery of 91.5% compared to traditional field conditions. We developed a new wheat NIL derived from cv. Jokyoung, a leading cultivar in Korea. Milyang56 exhibited improved protein content, sodium dodecyl sulfate-sedimentation value, and loaf volume compared to Jokyoung, which were attributed to introgression of the Glu-B1i allele from the donor parent, cv. Garnet. SBS represents a flexible breeding model that can be applied by breeders for developing breeding materials and mapping populations, as well as analyzing the environmental effects of specific genes or loci and for trait stacking. [ABSTRACT FROM AUTHOR]

Botanical seeds, also known as True Shallot Seed (TSS), are a new development to ensure the long-term availability of shallot seeds in the Bangka Belitung Islands. Apart from analyzing the effect of vernalization and gibberellin (GA3) on TSS production, this research aims to develop basic standard operating procedures for shallot TSS production in Bangka Belitung. This research was carried out on a plantation belonging to the Timur Makmur Farmers Group, Central Bangka. This research used a Randomized Block Design with two factors. Gibberellin concentration, namely 0, 50, 100, or 200 ppm, is the first factor, followed by vernalization time as the second factor, namely 0, 2, 4 weeks with 4 repetitions. Data were processed using the F test and the DMRT further test at the α = 5% level. Analysis of various uses of gibberellin and vernalization treatments showed that neither the Bima Brebes nor Biru Lancor varieties of shallots had any effect on height, number of leaves, or number of tillers. In both shallot varieties, the effect of gibberellin and vernalization treatment on flowering age, number of flowers set, and number of TSS seeds set had no effect. Vernalization treatment on shallots of the Bima Brebes variety can extend the flowering period of the Bima Brebes variety. Gibberellins and vernalization were not able to produce flowering in the Blue Lancor shallot variety. [ABSTRACT FROM AUTHOR]

Sugar beet (Beta vulgaris L.), a biennial sugar crop, contributes about 16% of the world’s sugar production. The transition from vegetative growth, during which sugar accumulated in beet, to reproductive growth, during which sugar exhausted in beet, is determined by vernalization and photoperiod. GIGANTEA (GI) is a key photoperiodic flowering gene that is induced by vernalization in sugar beet. To identify the upstream regulatory factors of BvGI, candidate transcription factors (TF) that were co-expressed with BvGI and could bind to the BvGI promoter were screened based on weighted gene co-expression network analysis (WGCNA) and TF binding site prediction. Subsequently, their transcriptional regulatory role on the BvGI was validated through subcellular localization, dual-luciferase assays and yeast transformation tests. A total of 7,586 differentially expressed genes were identified after vernalization and divided into 18 co-expression modules by WGCNA, of which one (MEcyan) and two (MEdarkorange2 and MEmidnightblue) modules were positively and negatively correlated with the expression of BvGI, respectively. TF binding site predictions using PlantTFDB enabled the screening of BvLHY, BvTCP4 and BvCRF4 as candidate TFs that negatively regulated the expression of BvGI by affecting its transcription. Subcellular localization showed that BvLHY, BvTCP4 and BvCRF4 were localized to the nucleus. The results of dual-luciferase assays and yeast transformation tests showed that the relative luciferase activity and expression of HIS3 was reduced in the BvLHY, BvTCP4 and BvCRF4 transformants, which suggested that the three TFs inhibited the BvGI promoter. In addition, real-time quantitative reverse transcription PCR showed that BvLHY and BvTCP4 exhibited rhythmic expression characteristics similar to that of BvGI, while BvCRF4 did not. Our results revealed that vernalization crosstalked with the photoperiod pathway to initiate bolting in sugar beet by inhibiting the transcriptional repressors of BvGI.Key message: BvLHY, BvTCP4 and BvCRF4, which were negative regulatory transcription factors of BvGI, were repressed by vernalization for bolting in sugar beet. [ABSTRACT FROM AUTHOR]

Synchronizing the timing of reproduction with the environment is crucial in the wild. Among the multiple mechanisms, annual plants evolved to sense their environment, the requirement of cold-mediated vernalization is a major process that prevents individuals from flowering during winter. In many annual plants including crops, both a long and short vernalization requirement can be observed within species, resulting in so-called early-(spring) and late-(winter) flowering genotypes. Here, using the grass model Brachypodium distachyon , we explored the link between flowering-time-related traits (vernalization requirement and flowering time), environmental variation, and diversity at flowering-time genes by combining measurements under greenhouse and outdoor conditions. These experiments confirmed that B. distachyon natural accessions display large differences regarding vernalization requirements and ultimately flowering time. We underline significant, albeit quantitative effects of current environmental conditions on flowering-time-related traits. While disentangling the confounding effects of population structure on flowering-time-related traits remains challenging, population genomics analyses indicate that well-characterized flowering-time genes may contribute significantly to flowering-time variation and display signs of polygenic selection. Flowering-time genes, however, do not colocalize with genome-wide association peaks obtained with outdoor measurements, suggesting that additional genetic factors contribute to flowering-time variation in the wild. Altogether, our study fosters our understanding of the polygenic architecture of flowering time in a natural grass system and opens new avenues of research to investigate the gene-by-environment interaction at play for this trait. [ABSTRACT FROM AUTHOR]

Summary: Many plant populations exhibit synchronous flowering, which can be advantageous in plant reproduction. However, molecular mechanisms underlying flowering synchrony remain poorly understood. We studied the role of known vernalization‐response and flower‐promoting pathways in facilitating synchronized flowering in Arabidopsis thaliana.Using the vernalization‐responsive Col‐FRI genotype, we experimentally varied germination dates and daylength among individuals to test flowering synchrony in field and controlled environments. We assessed the activity of flowering regulation pathways by measuring gene expression across leaves produced at different time points during development and through a mutant analysis.We observed flowering synchrony across germination cohorts in both environments and discovered a previously unknown process where flower‐promoting and repressing signals are differentially regulated between leaves that developed under different environmental conditions. We hypothesized this mechanism may underlie synchronization. However, our experiments demonstrated that signals originating from sources other than leaves must also play a pivotal role in synchronizing flowering time, especially in germination cohorts with prolonged growth before vernalization.Our results suggest flowering synchrony is promoted by a plant‐wide integration of flowering signals across leaves and among organs. To summarize our findings, we propose a new conceptual model of vernalization‐induced flowering synchrony and provide suggestions for future research in this field. [ABSTRACT FROM AUTHOR]

In the last few years, the world has experienced the impacts of climate change, such as elevated mean annual temperature, extreme weather events, drought, etc. Among living organisms, perennial plant species are the ones mostly exposed to climate change impacts, as they may experience different extreme events within the same year, such as flooding during some periods and drought in summer months, extremely low temperatures in winter but excessively high temperatures in summer, etc. Climate change affects a range of physiological functions of temperate fruit and nut tree species, such as their phenophases, bud dormancy release and vernalization, pollination and fruit set, fruit growth and quality, as well as bud sprouting and growth initiation. Besides these, the impact of climate change on pests, diseases, and weeds may generate significant negative interactions with tree physiology, threatening food production, food safety, and human welfare. In the present manuscript, a general aspect of climate change impacts on fruits’ and nut trees’ physiological functions is described and commented on.

In the last few years, the world has experienced the impacts of climate change, such as elevated mean annual temperature, extreme weather events, drought, etc. Among living organisms, perennial plant species are the ones mostly exposed to climate change impacts, as they may experience different extreme events within the same year, such as flooding during some periods and drought in summer months, extremely low temperatures in winter but excessively high temperatures in summer, etc. Climate change affects a range of physiological functions of temperate fruit and nut tree species, such as their phenophases, bud dormancy release and vernalization, pollination and fruit set, fruit growth and quality, as well as bud sprouting and growth initiation. Besides these, the impact of climate change on pests, diseases, and weeds may generate significant negative interactions with tree physiology, threatening food production, food safety, and human welfare. In the present manuscript, a general aspect of climate change impacts on fruits' and nut trees' physiological functions is described and commented on. [ABSTRACT FROM AUTHOR]

Adaptability of wheat to various environmental conditions, and wheat's seasonal growth habits and the development rate are mainly controlled by allelic diversity of VRN1 genes. Dominant allele Vrn-A1a is a major determinant of the spring growth habit of wheat. Recently, copy number variation of this allele was revealed. The present study is the first report on copy number variation of allele Vrn-A1a in European varieties of spring wheat. Unexpectedly, European varieties of wheat vary greatly in Vrn-A1a duplication. Although Vrn-A1a expression proved to be high enough to promote early flowering of wheat, despite its copy number in the genome, all the latest-flowering varieties carry a single haploid copy of this allele, implying an association of duplicated Vrn-A1a with early flowering of wheat. Vrn-A1a transcript abundance in dry embryos and expression dynamics of this allele during vegetative growth were analyzed in wheat varieties differing in this allele's copy number. Duplicated Vrn-A1a showed at least twofold higher expression at all developmental stages. The expression increase rate of this allele during wheat growth positively correlated with its basal transcription level. Although in some varieties, the expression of Vrn-A1a could decrease during wheat growth, this pattern was not found to be typical for this allele. Analysis of diurnal expression of Vrn-A1a uncovered a specific pattern with a peak of transcriptional activity at the beginning of the photoperiod and a subsequent decline. This pattern was similar to that observed for the Vrn-A1e allele and opposite to that of Vrn-A1b and Vrn-A1c. [ABSTRACT FROM AUTHOR]

Summary: Wheat needs different durations of vernalization, which accelerates flowering by exposure to cold temperature, to ensure reproductive development at the optimum time, as that is critical for adaptability and high yield. TaVRN1 is the central flowering regulator in the vernalization pathway and encodes a MADS‐box transcription factor (TF) that usually works by forming hetero‐ or homo‐dimers. We previously identified that TaVRN1 bound to an MADS‐box TF TaSOC1 whose orthologues are flowering activators in other plants. The specific function of TaSOC1 and the biological implication of its interaction with TaVRN1 remained unknown. Here, we demonstrated that TaSOC1 was a flowering repressor in the vernalization and photoperiod pathways by overexpression and knockout assays. We confirmed the physical interaction between TaSOC1 and TaVRN1 in wheat protoplasts and in planta, and further validated their genetic interplay. A Flowering Promoting Factor 1‐like gene TaFPF1‐2B was identified as a common downstream target of TaSOC1 and TaVRN1 through transcriptome and chromatin immunoprecipitation analyses. TaSOC1 competed with TaVRT2, another MADS‐box flowering regulator, to bind to TaVRN1; their coding genes synergistically control TaFPF1‐2B expression and flowering initiation in response to photoperiod and low temperature. We identified major haplotypes of TaSOC1 and found that TaSOC1‐Hap1 conferred earlier flowering than TaSOC1‐Hap2 and had been subjected to positive selection in wheat breeding. We also revealed that wheat SOC1 family members were important domestication loci and expanded by tandem and segmental duplication events. These findings offer new insights into the regulatory mechanism underlying flowering control along with useful genetic resources for wheat improvement. [ABSTRACT FROM AUTHOR]

Eleocharis carniolica W.D.J. Koch (Cyperaceae) is an endangered wetland spike rush mainly threatened by habitat loss and fragmentation. Understanding the germination ecology of this species is essential to perform successful conservation and restoration actions. In this study, we investigated the effect of vernalization (i.e. cold stratification), gibberellic acid (GA3) and chemical scarification on seed germination of E. carniolica from wild populations in northern Italy. The results showed that vernalization (i.e. 8-weeks at 4 °C) significantly improved germination probability, speed, and uniformity compared to non-stratified seeds. Gibberellic acid treatment alone or in combination with vernalization did not show a significant improvement in germination. Chemical scarification using sodium hypochlorite increased germination probability, with 8 h of scarification showing the highest success rate. However, 24-h scarification had a negative impact on germination. Overall, vernalization was found to be the most effective method to enhance germination in E. carniolica. These findings provide valuable insights into the seed germination ecology of this endangered species, aiding in its exsitu conservation, propagation, and in-situ restoration efforts. Moreover, they have important implications on future germination dynamics of this endangered species, especially with predicted climate change scenarios. [ABSTRACT FROM AUTHOR]

Cardiocrinum giganteum is an endemic species of east Asia which is famous for its showy inflorescence and medicinal bulbs. Its inflorescence is a determinate raceme and the flowers bloom synchronously. Morphological observation and time-course transcriptomic analysis were combined to study the process of inflorescence and flower development of C. giganteum. The results show that the autonomic pathway, GA pathway, and the vernalization pathway are involved in the flower formation pathway of C. giganteum. A varied ABCDE flowering model was deduced from the main development process. Moreover, it was found that the flowers in different parts of the raceme in C. giganteum gradually synchronized during development, which is highly important for both evolution and ecology. The results obtained in this work improve our understanding of the process and mechanism of inflorescence and flower development and could be useful for the flowering period regulation and breeding of C. giganteum. [ABSTRACT FROM AUTHOR]

Vernalization plays a crucial role in the flowering and yield of Chinese cabbage, a process intricately influenced by long non-coding RNAs (lncRNAs). Our research focused on lncFLC1, lncFLC2a, and lncFLC2b, which emerged as key players in this process. These lncRNAs exhibited an inverse expression pattern to the flowering repressor genes FLOWERING LOCUS C 1 (BrFLC1) and FLOWERING LOCUS C 2 (BrFLC2) during vernalization, suggesting a complex regulatory mechanism. Notably, their expression in the shoot apex and leaves was confirmed through in fluorescent in situ hybridization (FISH). Furthermore, when these lncRNAs were overexpressed in Arabidopsis, a noticeable acceleration in flowering was observed, unveiling functional similarities to Arabidopsis's COLD ASSISTED INTRONIC NONCODING RNA (COOLAIR). This resemblance suggests a potentially conserved regulatory mechanism across species. This study not only enhances our understanding of lncRNAs in flowering regulation, but also opens up new possibilities for their application in agricultural practices. [ABSTRACT FROM AUTHOR]

Rapid climate changes, with higher warming rates during winter and spring seasons, dramatically affect the vernalization requirements, one of the most critical processes for the induction of wheat reproductive growth, with severe consequences on flowering time, grain filling, and grain yield. Specifically, the Vrn genes play a major role in the transition from vegetative to reproductive growth in wheat. Recent advances in wheat genomics have significantly improved the understanding of the molecular mechanisms of Vrn genes (Vrn-1, Vrn-2, Vrn-3, and Vrn-4), unveiling a diverse array of natural allelic variations. In this review, we have examined the current knowledge of Vrn genes from a functional and structural point of view, considering the studies conducted on Vrn alleles at different ploidy levels (diploid, tetraploid, and hexaploid). The molecular characterization of Vrn-1 alleles has been a focal point, revealing a diverse array of allelic forms with implications for flowering time. We have highlighted the structural complexity of the different allelic forms and the problems linked to the different nomenclature of some Vrn alleles. Addressing these issues will be crucial for harmonizing research efforts and enhancing our understanding of Vrn gene function and evolution. The increasing availability of genome and transcriptome sequences, along with the improvements in bioinformatics and computational biology, offers a versatile range of possibilities for enriching genomic regions surrounding the target sites of Vrn genes, paving the way for innovative approaches to manipulate flowering time and improve wheat productivity. [ABSTRACT FROM AUTHOR]

The flowering loci of cabbage must be understood to boost their productivity. In this study, to clarify the flowering mechanisms of cabbage, we examined the three flowering repressors BoFLC1, 2 and 3, and the flowering regulators BoGI, BoCOOLAIR, and BoVIN3 of early (CAB1), middle (CAB3), and late (CAB5) flowering cabbage genotypes. Analysis of allele-specifically amplified genomic DNA and various sequence alignments demonstrated that maximal insertions and deletions influenced cabbage flowering behavior, notably in CAB3 and CAB5. Phylogenetic studies showed that BoFLC1, 2, and 3 in the CAB1, 3, and 5 genotypes had the highest homologies to other Brassica species, with CAB3 and 5 the most similar. Although CAB3 and CAB5 have comparable genetic patterns, flowering repressors and flowering regulators were investigated individually with and without vernalization to determine their minor flowering differences. The expression investigation revealed that vernalized CAB5 downregulated all BoFLC genes compared to CAB3 and, in contrast, CAB3 exhibited upregulated BoCOOLAIR. We hypothesized that the CAB3 BoFLC locus' additional insertions may have led to BoCOOLAIR overexpression and BoFLC downregulation. This study sheds light on cabbage genotypes—particularly those of CAB1 and CAB5—and suggests that structural variations in BoFLC2 and 3 bind flowering regulators, such as COOLAIR, which may affect cabbage flowering time. [ABSTRACT FROM AUTHOR]

A biennial sugar beet (Beta vulgaris) generally takes two years to flower and complete its life cycle. In year one, the plant grows vegetatively and then enters a cold winter period. In year two, the plant grows reproductively and initiates flowering under long-day conditions. Among biennial beets that grow vegetatively in outdoor field conditions, two test strains were preliminarily found to flower early under 24-h daylength conditions without being exposed to cold temperatures. To confirm the this phenomenon's genetics, crossings between the test strains and normal biennials yielded hybrid derivatives of F1, F2, and BC1F1, and bolting rate was investigated both in an outdoor field under natural daylength conditions and in a greenhouse with an artificial 24-h daylength. The test strains and hybrid derivatives did not bolt in the outdoor field, similar to the biennial control strains. This enables assessment of important agronomic traits, such as yield, which cannot be evaluated using an annual control strain in which all plants are bolted. However, under 24-h daylength conditions, the test strains bolted without vernalization treatment, unlike the biennial control strains, but similar to annuals. Hybrid derivatives' bolting rates suggest that the flowering characteristics of the test strains are mainly controlled by a single dominant gene. The flowering characteristics and the hypothetical responsible gene were named 'BLOND' and 'Bd', respectively. Because seed production in BLOND is estimated to take at least four months, similar to that of the annual beet, BLOND's bolt rate may be applicable for the speed breeding of sugar beets. [ABSTRACT FROM AUTHOR]

Noncoding transcription induces chromatin changes that can mediate environmental responsiveness, but the causes and consequences of these mechanisms are still unclear. Here, we investigate how antisense transcription (termed COOLAIR) interfaces with Polycomb Repressive Complex 2 (PRC2) silencing during winter-induced epigenetic regulation ofArabidopsis FLOWERING LOCUS C (FLC). We use genetic and chromatin analyses on lines ineffective or hyperactive for the antisense pathway in combination with computational modeling to define the mechanisms underlying FLC repression. Our results show that FLC is silenced through pathways that function with different dynamics: a COOLAIR transcription-mediated pathway capable of fast response and in parallel a slow PRC2 switching mechanism that maintains each allele in an epigenetically silenced state. Components of both the COOLAIR and PRC2 pathways are regulated by a common transcriptional regulator (NTL8), which accumulates by reduced dilution due to slow growth at low temperature. The parallel activities of the regulatory steps, and their control by temperature-dependent growth dynamics, create a flexible system for registering widely fluctuating natural temperature conditions that change year on year, and yet ensure robust epigenetic silencing of FLC. [ABSTRACT FROM AUTHOR]

Flowering is an essential process in plant development, and there are six major flowering pathways: the photoperiodic pathway, gibberellin pathway, vernalization pathway, age pathway, autonomous pathway, and temperature pathway. In this study, we screened the transcriptome sequencing of early flowering mutants from the laboratory for the significantly differentially expressed ZmGRAS46, which belongs to the DELLA subfamily of the GRAS family. DELLA is involved in the gibberellin pathway to regulate plant flowering. However, it is not clear whether ZmGRAS46 is involved in the gibberellin pathway which regulates plant flowering; therefore, in this experiment, we investigated the regulatory role of this gene in Arabidopsis flowering by overexpressing ZmGRAS46. It was found that overexpression of ZmGRAS46 in Arabidopsis promotes the formation of rosette leaves and flower buds and delays flowering time in Arabidopsis, and experiments have shown that ZmGRAS46 represses the expression of FLOWERING LOCUS T (FT), SUPPRESSOR OF CONSTANS1 (SOC1), CONSTANS (CO), and LEAFY (LFY). Our results indicated the possibility that ZmGRAS46 represses flowering through the CO-FT-SOC1-mediated photoperiodic flowering pathway. The delayed flowering phenotype of overexpressing ZmGRAS46 Arabidopsis could be rescued by applying GA3. The experimental results indicate that ZmGRAS46 depends on the GA3 pathway to regulate flowering in Arabidopsis. [ABSTRACT FROM AUTHOR]

Climate warming is causing shifts in key life‐history events, including flowering time. To assess the impacts of increasing temperature on flowering phenology, it is crucial to understand the transcriptional changes of genes underlying the phenological shifts. Here, we conducted a comprehensive investigation of genes contributing to the flowering phenology shifts in response to increasing temperature by monitoring the seasonal expression dynamics of 293 flowering‐time genes along latitudinal gradients in the perennial herb, Arabidopsis halleri. Through transplant experiments at northern, southern and subtropical study sites in Japan, we demonstrated that the flowering period was shortened as latitude decreased, ultimately resulting in the loss of flowering opportunity in subtropical climates. The key transcriptional changes underlying the shortening of the flowering period and the loss of flowering opportunity were the diminished expression of floral pathway integrator genes and genes in the gibberellin synthesis and aging pathways, all of which are suppressed by increased expression of FLOWERING LOCUS C, a central repressor of flowering. These results suggest that the upper‐temperature limit of reproduction is governed by a relatively small number of genes that suppress reproduction in the absence of winter cold. Summary statement: This study uncovered the transcriptional changes underlying the shift in flowering phenology in response to increasing temperature in a perennial herb, Arabidopsis halleri. The key transcriptional changes were the diminished expression of floral pathway integrator genes and genes in the gibberellin synthesis and aging pathways, all of which are suppressed by increased expression of FLOWERING LOCUS C, a central repressor of flowering. [ABSTRACT FROM AUTHOR]

In many plant species, flowering is promoted by the cold treatment or vernalization. The mechanism of vernalization-induced flowering has been extensively studied in Arabidopsis but remains largely unknown in legumes. The orthologs of the FLC gene, a major regulator of vernalization response in Arabidopsis, are absent or non-functional in the vernalization-sensitive legume species. Nevertheless, the legume integrator genes FT and SOC1 are involved in the transition of the vernalization signal to meristem identity genes, including PIM (AP1 ortholog). However, the regulatory contribution of these genes to PIM activation in legumes remains elusive. Here, we presented the theoretical and data-driven analyses of a feed-forward regulatory motif that includes a vernalization-responsive FT gene and several SOC1 genes, which independently activate PIM and thereby mediate floral transition. Our theoretical model showed that the multiple regulatory branches in this regulatory motif facilitated the elimination of no-sense signals and amplified useful signals from the upstream regulator. We further developed and analyzed four data-driven models of PIM activation in Medicago trancatula in vernalized and non-vernalized conditions in wild-type and fta1-1 mutants. The model with FTa1 providing both direct activation and indirect activation via three intermediate activators, SOC1a, SOC1b, and SOC1c, resulted in the most relevant PIM dynamics. In this model, the difference between regulatory inputs of SOC1 genes was nonessential. As a result, in the M. trancatula model, the cumulative action of SOC1a, SOC1b, and SOC1c was favored. Overall, in this study, we first presented the in silico analysis of vernalization-induced flowering in legumes. The considered vernalization network motif can be supplemented with additional regulatory branches as new experimental data become available. [ABSTRACT FROM AUTHOR]

Translocation of maturity factors through the basal plate of double-nose L. longiflorum Thunb. ‘Nellie White’ and L. ×elegans Thunb. was investigated. Both mother (M) and daughter (D) scales were attached (+M+D) or the scales were removed (-M-D) from one or both sides of the double-nose bulb. The double-nose ‘Nellie White’ bulbs were grouped into +M+D/+M+D, +M+D/-M-D, and -M-D/-M-D. The basal plate of the +M+D/-M-D ‘Nellie White’ bulb was separated 0, 10, 20, 30, and 40 days after potting. The basal plate of the +M+D/-M-D 'Inferno' bulb was separated at 0, 4, 8, and 16 days after potting. The maturity factor evaluated by the speed of shoot emergence and the number of flowers and leaves was translocated from the +M+D bulb to the -M-D bulb of the non-separated +M+D/-M-D bulb. The translocation of maturity factors in ‘Nellie White’ bulbs was completed before bulb separation in 40 days after potting. In ‘Inferno’ no differences in the number of flowers and leaves were observed between shoots that emerged from the +M+D bulb and the -M-D bulb of the +M+D/-M-D bulb, indicating that the maturity factors in ‘Inferno’ were not translocated. The differences in translocation responses between ‘Nellie White’ and ‘Inferno’ are that the shoot apex in ‘Nellie White’ is under the vegetative growth stage and the shoot apex in ‘Inferno’ is under the reproductive development stage when the vernalized bulbs are potted following scale removal treatment.

Tephroseris helenitis is a perennial herb that experienced a severe decline of species records over the last 120 years in the state of Hessia, Germany. Here, the species is found in humid habitats with moderate temperatures. In this modeling study, we assessed changes in climatic conditions between the periods 1900–1949, 1950–1979, 1980–1999 and 2000–2020 and explored whether these changes can explain the decline of records of T. helenitis. Climatic variables used were monthly precipitation sums, monthly mean, minimum and maximum temperatures, monthly temperature ranges as well as annual precipitation sum and annual mean temperature. For the majority of these variables, changes were significant across periods. Minimum temperatures in March, April and July (Tmin_Mar, Tmin_Apr, Tmin_Jul) best explained species presences and absences in 1900–1949 and 1950–1979. The species shifted its realized niche towards lower Tmin_Mar and narrowed its niche on Tmin_Apr and Tmin_Jul between these two periods. March, April and July are crucial in the life cycle of T. helenitis. Tmin_Mar and Tmin_Apr are related to the induction of flowering through a period of low temperatures (vernalization), and Tmin_Jul is related to seed germination. Documented increasing March and April temperatures as well as autumn and winter temperatures in the past 120 years may imply that vernalization became increasingly unsuccessful for the species and increasing July temperatures may have decreased its germination success. Given the disappearance of its temperature niche (Tmin_Mar, Tmin_Apr, Tmin_Jul) due to ongoing global warming not only in Hessia and Germany, we anticipate that T. helenitis will go extinct in Europe. [ABSTRACT FROM AUTHOR]

Plants grown at different latitudes perceive and interpret seasonal variations in day length (photoperiod) and exposure to cold winter temperatures (vernalization). These factors control the expression of various genes involved in flowering, depending on the variations in photoperiod and vernalization. Epigenetic regulatory systems have evolved in plants to process environmental signals. Gene expression is modified through chromatin remodelling and small RNAs in response to seasonal changes in both annual and perennial plants. Key regulators of flowering, such as FLOWERING LOCUS C (FLC) and FLOWERING LOCUS T (FT), interact with other floral regulatory factors and undergo chromatin remodelling in response to seasonal cues. The Polycomb repressive complex (PRC) controls the expression of flowering‐related genes in photoperiodic flowering regulation. FLC acts as a potent suppressor by down‐regulating the expression of genes that promote flowering. Methylation, particularly in the context of CHG, CG and CHH, plays a critical role in embryogenesis. This review briefly explores and describes the regulation of flowering mechanisms in response to day‐length variations, cold exposure (vernalization) and seed development in plants. [ABSTRACT FROM AUTHOR]

Low level of resistance to major diseases such as ascochyta blight (AB), botrytis grey mould (BGM) and dry root rot (DRR) in the cultivated chickpea genepool necessitates harnessing wild Cicer species. Sixty-eight accessions belonging to eight annual wild Cicer species and seven chickpea cultivars were screened for AB, BGM and DRR under controlled environmental conditions over the years. Intra-accession variability was observed among wild Cicer accessions for each disease. Hence, progenies of single resistant plants were selected for further evaluations and the trait-specific genetic stocks (TGS) were developed for each disease after re-screening following the single seed descent method. For AB, a high level of resistance was identified in four accessions belonging to tertiary genepool species, ICC 17334 (Cicer judaicum), ICC 17302, ICC 17308 and ICC 20177 (C. bijugum). Nine accessions, ICC 17160, ICC 17264, ICC 17270, ICC 20170, ICC 20186, ICC 20225, ICC 20247, ICC 20251 and IG 72941 of primary (C. reticulatum) and one accession, ICC 20190 of secondary (C. echinospermum) genepool species were resistant to BGM whereas, four accessions, ICC 20187 (C. reticulatum) and ICC 20218, ICC 20244 and ICC 20257 (C. echinospermum) were resistant to DRR. Development and utilization of these TGS in chickpea pre-breeding will assist in developing disease-resistant chickpea cultivars with broad genetic base. [ABSTRACT FROM AUTHOR]

Wheat is a staple food in many areas around the World. In the 20th century, breeders and scientists were able to boost wheat yield considerably. However, a yield plateau has become a concern and is threatening food security. Investments in cutting-edge technologies, including genomics and precision phenology measurements, can provide valuable tools to drive crop improvement. The objectives of this study were to (i) investigate the genetic diversity in a set of winter wheat lines, (ii) characterize their phenological response under different vernalization and photoperiod conditions, and (iii) identify effective markers associated with the phenological traits. A total of 249 adapted genotypes of different geographical origin were genotyped using the 35K Axiom® Wheat Breeder's Array. A total of 11,476 SNPs were used for genetic analysis. The set showed an average polymorphism information content of 0.37 and a genetic diversity of 0.43. A population structure analysis revealed three distinct subpopulations mainly related to their geographical origin (Europe, North America, and Western Asia). The lines of CGIAR origin showed the largest diversity and the lowest genetic distance to all other subpopulations. The phenology of the set was studied under controlled conditions using four combinations of long (19 h light) and short photoperiod (13 h light) and long vernalization (49 days at 5 °C) and no vernalization. With this, phenological traits such as earliness per se (Eps), relative response to vernalization (RRV), and relative response to photoperiod (RRP) were calculated. The phenotypic variation of growing degree days was significant in all phenology combinations. RRV ranged from 0 to 0.56, while RRP was higher with an overall average of 0.25. The GWAS analysis detected 30 marker-trait associations linked to five phenological traits. The highest significant marker was detected on chromosome 2D with a value of −log10(p) = 11.69. Only four loci known to regulate flowering exceeded the Bonferroni correction threshold of −log10(p) > 5.1. These results outline a solid foundation to address global food security and offer tremendous opportunities for advancing crop improvement strategies. [ABSTRACT FROM AUTHOR]

Veronica nakaiana Ohwi is a Korean endemic species and has potential value as an ornamental and breeding resource of Veronica species. Therefore, it is necessary to determine the environmental factors for floral induction to manipulate flowering for the industrial application of this plant. This study was conducted to investigate the flowering response of V. nakaiana to cold temperatures and photoperiod treatments. In Expt. 1, six-week-old seedlings were treated with a cold temperature of 5 °C for from 0 to 12 weeks. After the artificial cold treatments, the plants were subjected to the following photoperiod treatments: 9/15, 12/12, 14/10, 16/8, or 24/0 (day/night) h. In Expt. 2, seven-month-old plants were transferred to an open field for natural cold treatments and the chilling hours were calculated to quantify the flowering response to cold temperatures. In Expt. 1, the photoperiod does not affect the percent flowering or flowering time. The plants flowered only after artificial cold treatments lasting for more than eight weeks. However, the average percent flowering was less than half. In Expt. 2, although flowering was also observed only after more than eight weeks of natural cold treatment, the percent flowering in Expt. 2 was higher than that in Expt. 1. In both experiments, the number of days to flowering significantly decreased with increasing the cold treatment period. These results indicated that V. nakaiana is a day-neutral plant and requires a prolonged period of cold temperatures. In addition, the cold requirement showed an age-dependent response on flowering. [ABSTRACT FROM AUTHOR]

Flowering phenology is important in the adaptation of many plants to their local environment, but its adaptive value has not been extensively studied in herbaceous perennials. We used Arabis alpina as a model system to determine the importance of flowering phenology to fitness of a herbaceous perennial with a wide geographical range. Individual plants representative of local genetic diversity (accessions) were collected across Europe, including in Spain, the Alps and Scandinavia. The flowering behaviour of these accessions was documented in controlled conditions, in common-garden experiments at native sites and in situ in natural populations. Accessions from the Alps and Scandinavia varied in whether they required exposure to cold (vernalization) to induce flowering, and in the timing and duration of flowering. By contrast, all Spanish accessions obligately required vernalization and had a short duration of flowering. Using experimental gardens at native sites, we show that an obligate requirement for vernalization increases survival in Spain. Based on our analyses of genetic diversity and flowering behaviour across Europe, we propose that in the model herbaceous perennial A. alpina, an obligate requirement for vernalization, which is correlated with short duration of flowering, is favoured by selection in Spain where the plants experience a long growing season. [ABSTRACT FROM AUTHOR]

The transition to flowering is a major developmental switch in plants. In many temperate grasses, perception of indicators of seasonal change, such as changing day-length and temperature, leads to expression of FLOWERING LOCUS T1 (FT1) and FT-Like (FTL) genes that are essential for promoting the transition to flowering. However, little is known about the upstream regulators of FT1 and FTL genes in temperate grasses. Here, we characterize the monocot-specific gene INDETERMINATE1 (BdID1) in Brachypodium distachyon and demonstrate that BdID1 is a regulator of FT family genes. Mutations in ID1 impact the ability of the short-day (SD) vernalization, cold vernalization, and long-day (LD) photoperiod pathways to induce certain FTL genes. BdID1 is required for upregulation of FTL9 (FT-LIKE9) expression by the SD vernalization pathway, and overexpression of FTL9 in an id1 background can partially restore the delayed flowering phenotype of id1. We show that BdID1 binds in vitro to the promoter region of FTL genes suggesting that ID1 directly activates FTL expression. Transcriptome analysis shows that BdID1 is required for FT1, FT2, FTL12, and FTL13 expression under inductive LD photoperiods, indicating that BdID1 is a regulator of the FT gene family. Moreover, overexpression of FT1 in the id1 background results in rapid flowering similar to overexpressing FT1 in the wild type, demonstrating that BdID1 is upstream of FT family genes. Interestingly, ID1 negatively regulates a previously uncharacterized FTL gene, FTL4, and we show that FTL4 is a repressor of flowering. Thus, BdID1 is critical for proper timing of flowering in temperate grasses. [ABSTRACT FROM AUTHOR]

Sugar beet is an important root crop with a biennial life cycle. In the first year of its life cycle, it produces huge amounts of leaf and root mass used for the production of sugar and bioethanol, livestock feed, confectionery and pharmaceuticals, fertilizers, and soil restoration. Normally, after exposure to cold temperatures during winter storage, in the second year of its life cycle, it enters its reproductive phase. However, during the first year of growth, sugar beet plants may be susceptible to producing flowering shoots, or "bolting", due to vernalization and long-day conditions. Bolting reduces both the yield and the sugar content of roots. Here, we review the published research works that study the environmental factors influencing bolting, the genetic (including epigenetic) and physiological mechanisms that regulate the transition to the reproductive phase, and the agrotechnical and breeding practices used to prevent bolting. Models of gene networks that regulate the transition to flowering are presented. Methods for selecting non-bolting plants using conventional, marker-assisted, and genomic breeding are demonstrated. Attention is also paid to the speed breeding technology that stimulates bolting and flowering sugar beet plants in an artificial climate. Growing sugar beet plants "from seed to seed" can potentially accelerate the breeding and seed production of sugar beet. This review compares different conditions for inducing bolting in sugar beet in climatic chambers and greenhouses. It examines parameters such as temperature, duration of light exposure, and light intensity during the pre-vernalization, post-vernalization, and vernalization periods. The present review may be useful for specialists in sugar beet cultivation, breeders working on developing cultivars and hybrids that are resistant to bolting, and molecular biologists studying the genetic and physiological mechanisms underlying the transition of plants into the flowering stage. [ABSTRACT FROM AUTHOR]

Climate change is causing alterations in annual temperature regimes worldwide. Important aspects of this include the reduction of winter chilling temperatures as well as the occurrence of unpredicted frosts, both significantly affecting plant growth and yields. Recent studies advanced the knowledge of the mechanisms underlying cold responses and tolerance in the model plant Arabidopsis thaliana. However, how these cold‐responsive pathways will readjust to ongoing seasonal temperature variation caused by global warming remains an open question. In this review, we highlight the plant developmental programmes that depend on cold temperature. We focus on the molecular mechanisms that plants have evolved to adjust their development and stress responses upon exposure to cold. Covering both genetic and epigenetic aspects, we present the latest insights into how alternative splicing, noncoding RNAs and the formation of biomolecular condensates play key roles in the regulation of cold responses. We conclude by commenting on attractive targets to accelerate the breeding of increased cold tolerance, bringing up biotechnological tools that might assist in overcoming current limitations. Our aim is to guide the reflection on the current agricultural challenges imposed by a changing climate and to provide useful information for improving plant resilience to unpredictable cold regimes. Summary statement: In this review, we delve into the molecular mechanisms underlying plant responses to cold. We highlight recent insights into the (epi)genetic pathways controlling cold responses, identifying attractive targets with the potential to address some of the agricultural challenges imposed by climate change. [ABSTRACT FROM AUTHOR]

The timing of floral transition is determined by both endogenous molecular pathways and external environmental conditions. Among these environmental conditions, photoperiod acts as a cue to regulate the timing of flowering in response to seasonal changes. Additionally, it has become clear that various environmental factors also control the timing of floral transition. Environmental factor acts as either a positive or negative signal to modulate the timing of flowering, thereby establishing the optimal flowering time to maximize the reproductive success of plants. This review aims to summarize the effects of environmental factors such as photoperiod, light intensity, temperature changes, vernalization, drought, and salinity on the regulation of flowering time in plants, as well as to further explain the molecular mechanisms that link environmental factors to the internal flowering time regulation pathway. [ABSTRACT FROM AUTHOR]

The garlic seed bulbs cannot be planted immediately after harvest because has dormant period. Bulb dormancy can be broken by exposure of pre-planting bulbs to low temperatures. The research aimed to determine the sensitivity of different bolting types of garlic genotypes at low temperatures and the role of low temperatures on dormancy break. The experiment was conducted from March to June 2019 at the Universitas Brawijaya, using a nested design with three replications. Chinese hardneck and softneck, Sangga Sembalun and Tawangmangu Baru were the garlic accessions used in the study. The storage temperature treatments at 3 and 7°C; and room temperature at 27°C. Chinese softneck bulb had the highest sprouting and rooting after 3 and 7°C storage and was sensitive to low temperatures. The Chinese hardneck had the lowest sprouting and was highly insensitive to cold stress. Sangga Sembalun and Tawangmangu Baru had sprouted bulbs in between these Chinese genotypes, and they were insensitive and highly insensitive to low temperatures, respectively. Metabolites of 5-hydroxymethyl-2-furancarboxaldehyde, palmitic acid, diallyl trisulfide, and 2,3-dihydro-3,5-dihydroxy-6-methyl-4(H)-pyran-4-one played important roles in the bulb response to low temperature stress and directly or indirectly involved in the sprouting and rooting in dormant garlic cloves. [ABSTRACT FROM AUTHOR]

Chickpea is one of the most important plants of the legume family and is very important in the diet. In order to investigate the genetic diversity of chickpea, an experiment was conducted with 18 chickpea genotypes in the form of a completely to investigate the genetic diversity of chickpea, an experiment was conducted with 18 chickpea genotypes in the form of a completely randomized block design. After acclimatization of plants to cold, freezing treatment was applied at temperatures of -6, -8 and -10 and their 50% lethality temperature (LT50) was determined by probit transformation. Before and after the habituation stage, a leaf sample was taken and the relative content of leaf water, photosynthetic pigments, proline, soluble sugar, protein percentage, catalase, peroxidase, polyphenol oxidase and greenness index were measured. Genotype number 5 with the lowest LT50 (-8.86) and the highest survival percentage (80%) was the most resistant genotype and genotype 10 with the highest LT50 (-3.57) and the lowest survival percentage along with genotype 15 were recognized as the most sensitive genotypes. In order to evaluate genetic diversity, DNA extraction was utilized and 21 different ISSR primers were used in the investigation. The results showed the presence of polymorphism among the cultivars studied. A total of 101 clear bands were produced, of which 94 were polymorphic bands. Polymorphic information content (PIC) was in the range of 0.332 (initiator 7) to 0.049 (initiator 16). The amount of gene diversity was between 0.126 and 0.977 changes. Cluster analysis of genotypes was done using Jaccard similarity coefficient and UPGMA method

Abstract Background Vernalization, as a vital process in the life cycle of winter cereal, has important effects on floral organ formation and flowering time. Many morphological changes together with molecular changes occur during the vernalization period. Here, we used transcriptome sequencing to analyze the transcriptomic changes in wheat leaves before, during and after vernalization using the winter wheat cultivar ‘Shiluan02-1’. Results A total of 16,370 differentially expressed genes were obtained across different vernalization periods. Gene Ontology enrichment analysis revealed that photoperiodism, photoprotection, photosynthesis, lipid transport and biosynthetic process, and chlorophyll metabolic process were closely related to vernalization. In addition, AP2/ERF, C2H2, bHLH, WRKY, MYB, MYB-related, and NAC transcription factors were significantly enriched during vernalization, and the transcription factor expression patterns suggested the intricate regulation of transcription factor modules in plant vernalization pathways. Analysis of gene expression patterns of the MADS-box transcription factor genes showed different expression patterns during vernalization phases, among which VERNALIZATION1 (VRN1) genes were found to gradually increase during vernalization periods from V0 to V35, while decline in the V42 phase, then increase after vernalization. The Tavrt-2 gene cooperated with Tavrn1 to regulate flowering induced by vernalization, and its expression level was rapidly increased by vernalization but declined in the V42 phase and then increased after vernalization. Some genes from the ICE-CBF-COR pathway were also identified, and additional analysis indicated that some key genes related to phytohormone biosynthesis and signal transduction were enriched during the vernalization period, such as gibberellic acid, ethylene, abscisic acid and jasmonic acid biosynthesis and signaling pathway genes. Conclusions Our study provides valuable molecular information for future studies on wheat vernalization regulation and also serves as an excellent reference for future wheat breeding.

Bolting and flowering of vegetables are induced by vernalization in their early growth stage. This phenomenon is called premature bolting, and it has caused massive losses in production of vegetables such as cabbage, celery, carrot, radish, and spinach, etc. This review aimed to summarize studies on bolting and flowering pathways, physiological and biochemical changes, and underlined molecular mechanisms of various vegetable crop bolting involving genome and transcriptome analysis, and its association with vegetable breeding. This review could provide basic knowledge to carry out research on vegetable genetics and breeding and vegetable cultivation.

Ranunculus asiaticus L. is an ornamental geophyte. In commercial practice, it is mainly propagated by rehydrated tuberous roots. Vernalization before planting is a common practice to overcome the natural dormancy of tuberous roots; however, little is known about the mechanisms underlying the plant's response to low temperatures. We investigated the influence of three preparation procedures of tuberous roots, only rehydration (control, C), and rehydration plus vernalization at 3.5 °C for 2 weeks (V2) and for 4 weeks (V4), on plant growth, leaf photosynthesis, flowering, and metabolism in plants of two hybrids, MBO (early flowering, pale orange flower) and MDR (medium earliness, bright orange flower), grown in pots in an unheated greenhouse. We reported the responses observed in the aerial part in a previous article in this journal. In this paper, we show changes in the underground organs in carbohydrate, amino acids, polyphenols, and protein levels throughout the growing cycle in the different plant stages: pre-planting, vegetative growth, and flowering. The metabolic profile revealed that the two hybrids had different responses to the root preparation procedure. In particular, MBO synthesized GABA and alanine after 2 weeks and sucrose after 4 weeks of vernalization. In contrast, MDR was more sensitive to vernalization; in fact, a higher synthesis of polyphenols was observed. However, both hybrids synthesized metabolites that could withstand exposure to low temperatures. [ABSTRACT FROM AUTHOR]

[Objective] The study aimed to clone and expression analysis of VIN3-LIKE 2 (VIL2) gene in Wucai (Brassica campestris L.), which will provide a foundation for further study on the function of BCVIL2 gene. [Method] Wucai variety 'Huiwu 19' was utilized as the experimental material. The BcVIL2 gene was obtained by homologous cloning, and its protein molecular weight (MW), glycosylation site, and secondary structure were analyzed using bioinformatics tools. The expression pattern of BCVIL2 gene in response to vernalization was examined by quantitative real-time polymerase chain reaction (qRT-PCR). [Result] BcVIL2 gene ORF (Open reading fragment) was 1296 bp and encoded 431 amino acids, belonged to a hydrophilic protein, containing 1 N-glycosylation potential site and 59 phosphorylation potential sites. BcVIL2 protein MW was 47.91 kDa and the theoretical isoelectric point (pl) was 8.27. Its secondary structure was composed of a-helices and random coil. Subcellular localization predicted its possible role in the nucleus. Sequence alignment analysis showed that BCVIL2 gene had high homologous with several VIL2 genes from Brassica plants; Phylogenetic tree analysis also showed that BCVIL2 gene was close to BcVIL2 and BjVIL2 genes. The results of quantitative PCR showed that the expression of BcVIL2 gene was the lowest in roots and the highest in pods, while the expression in leaves was significantly lower than that in stems and flowers and the expression of BCVIL2 after vernalization was significantly lower than that before vernalization. [Conclusion] The BcVIL2 gene is down-regulated by vernalization and closely related to several vernalization related genes, BraA01g032910.3C, BraA05g026410. 3C and BraA10g016160.3C, and there might be interaction between them. The study provides a foundation for further study on the function of BCVIL2 gene. [ABSTRACT FROM AUTHOR]