scholarly journals A LONG-DAY GENE FOR FLOWERING TIME IN LACTUCA

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1168g-1168 ◽  
Author(s):  
Edward J. Ryder
Keyword(s):  
Flowering Time ◽  
Single Gene ◽  
Early Flowering ◽  
Evolutionary Significance ◽  
Major Genes ◽  
Late Flowering ◽  
Long Day ◽  
Quantitative Manner ◽  
Discrete Effect ◽  
Short Days

Genes for flowering time appear to be relatively common in lettuce and other Lactuca species. These include previously described major genes Ef-1 an Ef-2, other genes of discrete effect and genes acting in a quantitative manner. Our goals in studying the flowering time phenomenon are: 1)describe the inheritance of the traits, 2) establish their relationship to each other, and 3) elucidate their evolutionary significance.The PI 175735 (L. serriola) is an accession with narrow leaves, spines and anthocyanin. Its flowering time is daylength related; it is early flowering under long days and late flowering under short days. It was crossed with the late flowering line C-2-1-1, which is homozygous for both late alleles in the Ef system. The F1 is late under short days and early under long days. The F2 population and F3 families were grown under long day conditions in the greenhouse, Segregation in the F2 was 3 early: 1 late. Among F3 families from early plants, segregation was 1 homozygous early: 2 segregating. Within segregating families, the ratio was again 3:1. The evidence suggests a single gene with earliness dominant.

scholarly journals A LONG-DAY GENE FOR FLOWERING TIME IN LACTUCA

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1168G-1168
Author(s):  
Edward J. Ryder
Keyword(s):  
Flowering Time ◽  
Single Gene ◽  
Early Flowering ◽  
Evolutionary Significance ◽  
Major Genes ◽  
Late Flowering ◽  
Long Day ◽  
Quantitative Manner ◽  
Discrete Effect ◽  
Short Days

Genes for flowering time appear to be relatively common in lettuce and other Lactuca species. These include previously described major genes Ef-1 an Ef-2, other genes of discrete effect and genes acting in a quantitative manner. Our goals in studying the flowering time phenomenon are: 1)describe the inheritance of the traits, 2) establish their relationship to each other, and 3) elucidate their evolutionary significance. The PI 175735 (L. serriola) is an accession with narrow leaves, spines and anthocyanin. Its flowering time is daylength related; it is early flowering under long days and late flowering under short days. It was crossed with the late flowering line C-2-1-1, which is homozygous for both late alleles in the Ef system. The F1 is late under short days and early under long days. The F2 population and F3 families were grown under long day conditions in the greenhouse, Segregation in the F2 was 3 early: 1 late. Among F3 families from early plants, segregation was 1 homozygous early: 2 segregating. Within segregating families, the ratio was again 3:1. The evidence suggests a single gene with earliness dominant.

The early-flowering mutant efs is involved in the autonomous promotion pathway of Arabidopsis thaliana

Development ◽  
1999 ◽  
Vol 126 (21) ◽  
pp. 4763-4770 ◽  
Author(s):  
W.J. Soppe ◽  
L. Bentsink ◽  
M. Koornneef
Keyword(s):  
Arabidopsis Thaliana ◽  
Flowering Time ◽  
Double Mutant ◽  
Plant Size ◽  
Early Flowering ◽  
Wild Type ◽  
Late Flowering ◽  
Long Day ◽  
Short Days ◽  
Transition To Flowering

The transition to flowering is a crucial moment in a plant's life cycle of which the mechanism has only been partly revealed. In a screen for early flowering, after mutagenesis of the late-flowering fwa mutant of Arabidopsis thaliana, the early flowering in short days (efs) mutant was identified. Under long-day light conditions, the recessive monogenic efs mutant flowers at the same time as wild type but, under short-day conditions, the mutant flowers much earlier. In addition to its early-flowering phenotype, efs has several pleiotropic effects such as a reduction in plant size, fertility and apical dominance. Double mutant analysis with several late-flowering mutants from the autonomous promotion (fca and fve) and the photoperiod promotion (co, fwa and gi) pathways of flowering showed that efs reduces the flowering time of all these mutants. However, efs is completely epistatic to fca and fve but additive to co, fwa and gi, indicating that EFS is an inhibitor of flowering specifically involved in the autonomous promotion pathway. A vernalisation treatment does not further reduce the flowering time of the efs mutant, suggesting that vernalisation promotes flowering through EFS. By comparing the length of the juvenile and adult phases of vegetative growth for wild-type, efs and the double mutant plants, it is apparent that efs mainly reduces the length of the adult phase.

scholarly journals Characterization of genes and alleles involved in the control of flowering time in grapevine

2019 ◽  
Author(s):  
Nadia Kamal ◽  
Iris Ochßner ◽  
Anna Schwandner ◽  
Prisca Viehöver ◽  
Ludger Hausmann ◽  
...  
Keyword(s):  
Flowering Time ◽  
Candidate Genes ◽  
Mapping Population ◽  
Early Flowering ◽  
Chromosome 1 ◽  
Model Organisms ◽  
Bud Burst ◽  
Perennial Crop ◽  
Inflorescence Development ◽  
Late Flowering

AbstractGrapevine (Vitis vinifera) is one of the most important perennial crop plants in worldwide. Understanding of developmental processes like flowering, which impact quality and quantity of yield in this species is therefore of high interest. This gets even more important when considering some of the expected consequences of climate change. Earlier bud burst and flowering, for example, may result in yield loss due to spring frost. Berry ripening under higher temperatures will impact wine quality. Knowledge of interactions between a genotype or allele combination and the environment can be used for the breeding of genotypes that are better adapted to new climatic conditions. To this end, we have generated a list of more than 500 candidate genes that may play a role in the timing of flowering. The grapevine genome was exploited for flowering time control gene homologs on the basis of functional data from model organisms likeA. thaliana. In a previous study, a mapping population derived from early flowering GF.GA-47-42 and late flowering ‘Villard Blanc’ was analyzed for flowering time QTLs. In a second step we have now established a workflow combining amplicon sequencing and bioinformatics to follow alleles of selected candidate genes in the F1individuals and the parental genotypes. Allele combinations of these genes in individuals of the mapping population were correlated with early or late flowering phenotypes. Specific allele combinations of flowering time candidate genes within and outside of the QTL regions for flowering time on chromosome 1, 4, 14, 17, and 18 were found to be associated with an early flowering phenotype. In addition, expression of many of the flowering candidate genes was analyzed over consecutive stages of bud and inflorescence development indicating functional roles of these genes in the flowering control network.

scholarly journals GWAS unveils features between early- and late-flowering pearl millets

2020 ◽  
Author(s):  
Oumar Diack ◽  
Ghislain Kanfany ◽  
Mame Codou Gueye ◽  
Ousmane Sy ◽  
Amadou Fofana ◽  
...  
Keyword(s):  
Flowering Time ◽  
Candidate Genes ◽  
Plant Height ◽  
Pearl Millet ◽  
Early Flowering ◽  
P Value ◽  
Phenotypic Traits ◽  
Gene Pools ◽  
Climate Change Scenarios ◽  
Late Flowering

Abstract Background: Pearl millet, a dietary food for around 100 million people in Africa and in India, has a large diversity due to an extensive genetic diversity combined with a high degree of admixture with wild relatives. In Senegal, two major morphotypes are distinguished: early-flowering and late-flowering millets. The phenotypic variabilities according to the flowering time plays an important role in pearl millet adaptation to climate variability. A better understanding of the genetic makeup of these variabilities would allow breeding of pearl millet fitting different climatic areas. In this study, we aimed to characterize the genetic basis of these phenotypic differences. Results: We defined a core collection capturing most of the diversity of cultivated pearl millet of Senegal, which includes 60 early-flowering Souna and 31 late-flowering Sanio. This panel was evaluated during the 2016 and 2017 rainy seasons at Nioro for 16 agro-morphological traits. Phenological and phenotypic traits linked with yield, flowering time, and biomass helped differentiated early- and late-flowering millets. Further, using genotyping-by-sequencing (GBS), 21,663 single nucleotide polymorphisms (SNPs) with minor allele frequencies of more than 5% were identified. Sparse Non-Negative Matrix Factorization (sNMF) analysis confirms the genetic structure in two gene pools associated with flowering time differences. Moreover, two chromosomal regions on linkage groups (LG 3) (~89.7Mb) and (LG 6) (~68.1Mb) differentiated the early-flowering into two clusters. Genome-wide association study (GWAS) was used to associate phenotypic variation to the SNPs and 18 genes were linked to flowering time, plant height, nodal tiller number, and biomass (P-value ˂ 2.3E-06). Conclusions: The diversity of early- and late-flowering pearl millet landraces of Senegal was captured using a heuristic approach. Key phenology and phenotypic traits, SNPs, and candidate genes underlying flowering time, tillering, biomass and plant height of pearl millet were identified. Chromosome rearrangements in LG3 and LG6 were implicated as a source of variation in early-flowering morphotypes. Using candidate genes underlying these features between pearl millet morphotypes would have paramount importance in breeding strategies under climate change scenarios.

scholarly journals GWAS unveils features between early- and late-flowering pearl millets

BMC Genomics ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Oumar Diack ◽  
Ghislain Kanfany ◽  
Mame Codou Gueye ◽  
Ousmane Sy ◽  
Amadou Fofana ◽  
...  
Keyword(s):  
Flowering Time ◽  
Candidate Genes ◽  
Plant Height ◽  
Pearl Millet ◽  
Climatic Variability ◽  
Early Flowering ◽  
Phenotypic Traits ◽  
Gene Pools ◽  
Late Flowering ◽  
A Genome

Abstract Background Pearl millet, a nutritious food for around 100 million people in Africa and India, displays extensive genetic diversity and a high degree of admixture with wild relatives. Two major morphotypes can be distinguished in Senegal: early-flowering Souna and late-flowering Sanio. Phenotypic variabilities related to flowering time play an important role in the adaptation of pearl millet to climate variability. A better understanding of the genetic makeup of these variabilities would make it possible to breed pearl millet to suit regions with different climates. The aim of this study was to characterize the genetic basis of these phenotypic differences. Results We defined a core collection that captures most of the diversity of cultivated pearl millets in Senegal and includes 60 early-flowering Souna and 31 late-flowering Sanio morphotypes. Sixteen agro-morphological traits were evaluated in the panel in the 2016 and 2017 rainy seasons. Phenological and phenotypic traits related with yield, flowering time, and biomass helped differentiate early- and late-flowering morphotypes. Further, using genotyping-by-sequencing (GBS), 21,663 single nucleotide polymorphisms (SNPs) markers with more than 5% of minor allele frequencies were discovered. Sparse non-negative matrix factorization (sNMF) analysis confirmed the genetic structure in two gene pools associated with differences in flowering time. Two chromosomal regions on linkage groups (LG 3) (~ 89.7 Mb) and (LG 6) (~ 68.1 Mb) differentiated two clusters among the early-flowering Souna. A genome-wide association study (GWAS) was used to link phenotypic variation to the SNPs, and 18 genes were linked to flowering time, plant height, tillering, and biomass (P-value < 2.3E-06). Conclusions The diversity of early- and late-flowering pearl millet morphotypes in Senegal was captured using a heuristic approach. Key phenological and phenotypic traits, SNPs, and candidate genes underlying flowering time, tillering, biomass yield and plant height of pearl millet were identified. Chromosome rearrangements in LG3 and LG6 were inferred as a source of variation in early-flowering morphotypes. Using candidate genes underlying these features between pearl millet morphotypes will be of paramount importance in breeding for resilience to climatic variability.

A systematic comparison of morphology and seed proteins of early- and late-flowering forms of Medicago scutellata

1993 ◽  
Vol 71 (1) ◽  
pp. 183-192
Author(s):  
Ernest Small ◽  
Gary R. Bauchan ◽  
Rosemary Salter ◽  
Brenda Brookes ◽  
Geoff C. Auricht
Keyword(s):  
Flowering Time ◽  
Polyacrylamide Gel Electrophoresis ◽  
Seed Proteins ◽  
Bimodal Distribution ◽  
Early Flowering ◽  
Distribution Area ◽  
Mediterranean Islands ◽  
Form Analysis ◽  
Late Flowering ◽  
Medicago Scutellata

Two hundred and thirty-nine germ plasm accessions of Medicago scutellata grown under greenhouse conditions exhibited a strongly bimodal distribution of flowering time. Numerical taxonomic analysis showed that the early- and late-flowering forms are substantially different morphologically. The early-flowering form is smaller and less vigorous, has fewer flowers in the inflorescence, and fewer serrations on the leaf blades and stipules than the late-flowering form. Analysis of seed proteins using polyacrylamide gel electrophoresis identified 11 seed proteins that can be used to distinguish the two forms and putative hybrids. Although both forms appear widespread in the circum-Mediterranean indigenous distribution area, only about one-third of the accessions represented the early-flowering form, which seemed to predominate only on isolated Mediterranean islands. The two forms may merit infraspecific taxonomic recognition. Key words: Medicago scutellata, Fabaceae, taxonomy, classification, systematics, seed proteins, electrophoresis, flowering time.

scholarly journals Kadife (Tagetes erecta) Bitkisinde Gün Uzunluğunun Büyüme ve Çiçeklenme Üzerine Etkisi

2017 ◽  
Vol 5 (10) ◽  
pp. 1189 ◽  
Author(s):  
Nezihe Köksal ◽  
Sara Yasemin ◽  
Aslıhan Özkaya
Keyword(s):  
Flowering Time ◽  
Early Flowering ◽  
Day Length ◽  
Flowering Plant ◽  
Plant Canopy ◽  
Flower Bud ◽  
Bud Formation ◽  
Short Day ◽  
Long Day ◽  
Flower Bud Formation

Photoperiod is one of the environmental signals that controls of the flowering time on bedding plants. Marigold is a bedding plant which includes obligate or facultative short day and day neutral cultivars. Flowering time of these plants, even day neutral cultivars, delay in extreme hot and long day condition in summer. In this study, the effects of photoperiodic conditions (short day and long day) on flowering and growth of two different day neutral marigold cultivars (Discovery Orange and Discovery Yellow) were investigated. Natural day length (14 hours) was considered as long day condition. Short day condition (8 hours) was conducted artificially by darkening treatment. Therefore, duration to first flower bud formation, duration to first flowering, plant canopy height, plant canopy width, lateral branch number, flower number, main peduncle length, main peduncle thickness, root collar thickness, stem thickness, dry weights of plants (root, shoot, total plant) were evaluated. At the end of the experiment, it was determined that short day conditions reduce duration to first flower bud formation and duration to first flowering. The artificial short day conditions resulted as 13 days early flowering in 'Discovery Orange' and 5 days early flowering in 'Discovery Yellow' cultivar.

scholarly journals Flowering-Time Genes Modulate the Response to LEAFY Activity

Genetics ◽  
1998 ◽  
Vol 150 (1) ◽  
pp. 403-410
Author(s):  
Ove Nilsson ◽  
Ilha Lee ◽  
Miguel A Blázquez ◽  
Detlef Weigel
Keyword(s):  
Flowering Time ◽  
Genetic Control ◽  
Genetic Interactions ◽  
Early Flowering ◽  
Late Flowering ◽  
Large Group ◽  
Meristem Identity ◽  
Transcriptional Induction ◽  
Transition To Flowering

Abstract Among the genes that control the transition to flowering in Arabidopsis is a large group whose inactivation causes a delay in flowering. It has been difficult to establish different pathways in which the flowering-time genes might act, because mutants with lesions in these genes have very similar phenotypes. Among the putative targets of the flowering-time genes is another group of genes, which control the identity of individual meristems. Overexpression of one of the meristem-identity genes, LEAFY, can cause the precocious generation of flowers and thus early flowering. We have exploited the opposite phenotypes seen in late-flowering mutants and LEAFY overexpressers to clarify the genetic interactions between flowering-time genes and LEAFY. According to epistatic relationships, we can define one class of flowering-time genes that affects primarily the response to LEAFY activity, and another class of genes that affects primarily the transcriptional induction of LEAFY. These observations allow us to expand previously proposed models for the genetic control of flowering time.

Ability of alleles of PPD1 and VRN1 genes to predict flowering time in diverse Australian wheat (Triticum aestivum) cultivars in controlled environments

2018 ◽  
Vol 69 (11) ◽  
pp. 1061 ◽  
Author(s):  
Maxwell T. Bloomfield ◽  
James R. Hunt ◽  
Ben Trevaskis ◽  
Kerrie Ramm ◽  
Jessica Hyles
Keyword(s):  
Triticum Aestivum ◽  
Molecular Markers ◽  
Flowering Time ◽  
Thermal Time ◽  
Major Genes ◽  
Short Day ◽  
Long Day ◽  
Major Development ◽  
Controlled Environments ◽  
New Cultivars

Flowering time of wheat (Triticum aestivum L.) is a critical determinant of grain yield. Frost, drought and heat stresses from either overly early or overly late flowering can inflict significant yield penalties. The ability to predict time of flowering from different sowing dates for diverse cultivars across environments in Australia is important for maintaining yield as autumn rainfall events become less reliable. However, currently there are no models that can accurately do this when new cultivars are released. Two major Photoperiod1 and three Vernalisation1 development genes, with alleles identified by molecular markers, are known to be important in regulating phasic development and therefore time to anthesis, in response to the environmental factors of temperature and photoperiod. Allelic information from molecular markers has been used to parameterise models that could predict flowering time, but it is uncertain how much variation in flowering time can be explained by different alleles of the five major genes. This experiment used 13 elite commercial cultivars of wheat, selected for their variation in phenology and in turn allelic variation at the major development genes, and 13 near-isogenic lines (NILs) with matching multi-locus genotypes for the major development genes, to quantify how much response in time to flowering could be explained by alleles of the major genes. Genotypes were grown in four controlled environments at constant temperature of 22°C with factorial photoperiod (long or short day) and vernalisation (±) treatments applied. NILs were able to explain a large proportion of the variation of thermal time to flowering in elite cultivars in the long-day environment with no vernalisation (97%), a moderate amount in the short-day environment with no vernalisation (62%), and less in the short-day (51%) and long-day (47%) environments with vernalisation. Photoperiod was found to accelerate development, as observed in a reduction in phyllochron, thermal time to heading, thermal time to flowering, and decreased final leaf numbers. Vernalisation response was not as great, and rates of development in most genotypes were not significantly increased. The results indicate that the alleles of the five major development genes alone cannot explain enough variation in flowering time to be used to parameterise gene-based models that will be accurate in simulating flowering time under field conditions. Further understanding of the genetics of wheat development, particularly photoperiod response, is required before a model with genetically based parameter estimates can be deployed to assist growers to make sowing-time decisions for new cultivars.

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