Distribution and variability in development of the genus Trigonella in Asia Minor and its possible use in Australian environments

1981 ◽  
Vol 32 (5) ◽  
pp. 793 ◽  
Author(s):  
GM Halloran ◽  
AL Pennell
Keyword(s):  
Flowering Time ◽  
Subterranean Clover ◽  
Asia Minor ◽  
Vernalization Response ◽  
Developmental Patterns ◽  
Late Flowering ◽  
Commercial Cultivars ◽  
Wide Variability ◽  
Upper Level ◽  
Autumn Sowing

A number of Trigonella species were examined for their possible use in Australian environments. There was a wide variability in flowering time in Trigonella. Under an outdoor autumn sowing the range in flowering time was comparable with that found within early- to late-flowering Australian commercial cultivars of subterranean clover. The upper level of vernalization response was much lower in Trigonella than in subterranean clover. Good prospects exist within Trigonella for selecting genotypes with close adaptation (in terms of appropriate developmental patterns) to a range of Australian environments, a range at least as wide as that now occupied by subterranean clover and annual medic.

Dynamics of flower and pod production in annual medics. (Medicago spp.). II. In swards at low and high density

1990 ◽  
Vol 41 (5) ◽  
pp. 923 ◽  
Author(s):  
PS Cocks
Keyword(s):  
Flowering Time ◽  
Seed Size ◽  
Seed Yield ◽  
Subterranean Clover ◽  
Farming Systems ◽  
High Density ◽  
Low Density ◽  
Medicago Polymorpha ◽  
Late Flowering ◽  
Annual Medics

Seven accessions of five annual medic species were grown in swards at low and high densities at Tel Hadya in north Syria. Flower shedding, seed size, and other components of seed yield were compared with data collected from spaced plants. Seed yield of the seven accessions, ranging from zero to 800 kg ha-1, was correlated with flowering time at high density but not at low density. Early flowering accessions of Medicago polymorpha and M. truncatula produced more seed at high density than at low density, but a late-flowering accession of M noeana failed to produce seed at high density. Flower shedding was greatest in dense swards and least in spaced plants. Shedding of the various accessions ranged from 70% to M. polymorpha at low density to 96% in M. rigidula and 100% in M. noeana at high density. Some accessions shed flowers uniformly from all nodes, but in other accessions late-produced flowers were more likely to be shed. The flower shedding observed here was less than found in many other legumes, but more than has been observed in subterranean clover. It seems unlikely that seed yield can be increased by selecting for increased flower retention, but it may be possible to increase seed numbers at the expense of seed size; this may be useful in pasturebased farming systems.

Flowering time of cultivars of subterranean clover in New South Wales

1987 ◽  
Vol 27 (6) ◽  
pp. 791 ◽  
Author(s):  
KA Archer ◽  
EC Wolfe ◽  
BR Cullis
Keyword(s):  
Flowering Time ◽  
Western Australia ◽  
New South ◽  
New South Wales ◽  
Subterranean Clover ◽  
Sowing Date ◽  
Late Flowering ◽  
Acceptable Accuracy ◽  
South Wales ◽  
The Relationship

The period from sowing to flowering was determined for 8 subterranean clover cultivars sown in late March, late April and late May at 9 environmentally distinct locations in New South Wales. The length of the period to flowering depended on cultivar (ranging from a mean of 1 12 days for Northam to 151 days for Larisa) and site (from a mean of 1 18 days at Grafton to 145 days at Canberra). There was a greater range in the period from sowing to flowering between cultivars at earlier flowering sites compared with late flowering sites. The period from sowing to flowering decreased with later sowings so that clovers sown late (May) flowered on average less than 14 days after those sown early (March). A relationship was developed between temperature and latitude and the period to flowering for each sowing date and cultivar. This relationship accounted for 95% of the variation in flowering time observed in this study and was used to predict with acceptable accuracy the flowering time of subterranean clover cultivars in a study undertaken in Western Australia in 1972 and 1973. We believe the relationship could be useful in predicting flowering time in subterranean clovers.

scholarly journals Diversity within subterranean clover and biserrula for persistence traits with potential use in New Zealand hill country

2016 ◽  
Vol 16 ◽  
pp. 299-307
Author(s):  
K. Ghamkhar ◽  
T. Faithful ◽  
P.G.H. Nichols ◽  
M.H. Ryan
Keyword(s):  
New Zealand ◽  
Microsatellite Markers ◽  
Flowering Time ◽  
Core Collection ◽  
Growth Habit ◽  
Subterranean Clover ◽  
Late Flowering ◽  
Hill Country ◽  
Forage Species ◽  
Potential Use

As part of an investigation into the potential of alternative forage species and/or germplasm in New Zealand's hill country and the traits required for their success, two F2 populations, their original parents, and 34 cultivars of subterranean clover (Trifolium subterranean) were evaluated for hardseededness in Australia. The 34 cultivars were also screened for burr burial strength and flowering time. Microsatellite markers were also used to investigate their association with these traits. The polygenic nature of hardseededness was confirmed and markers associated with this trait were detected and traits for New Zealand's hill country were identified. Additionally, a core collection of 30 (two cultivars and 28 wild) biserrula (Biserrula pelecinus) accessions was screened for flowering time, growth habit and leaflet size. Also, a subset of five accessions of biserrula exhibited traits that are desirable for hill country, namely, mid-late flowering and adaptation to lowmedium rainfall. Keywords: biserrula, flowering time, hardseededness, hill country, subterranean clover

scholarly journals Inter-species functional compatibility of the Theobroma cacao and Arabidopsis FT orthologs: 90 million years of functional conservation of meristem identity genes

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
S. F. Prewitt ◽  
A. Shalit-Kaneh ◽  
S. N. Maximova ◽  
M. J. Guiltinan
Keyword(s):  
Gene Expression ◽  
Tissue Culture ◽  
Gene Family ◽  
Flowering Time ◽  
Molecular Mechanisms ◽  
Regulatory Pathways ◽  
Late Flowering ◽  
Precocious Flowering ◽  
Transition To Flowering

Abstract Background In angiosperms the transition to flowering is controlled by a complex set of interacting networks integrating a range of developmental, physiological, and environmental factors optimizing transition time for maximal reproductive efficiency. The molecular mechanisms comprising these networks have been partially characterized and include both transcriptional and post-transcriptional regulatory pathways. Florigen, encoded by FLOWERING LOCUS T (FT) orthologs, is a conserved central integrator of several flowering time regulatory pathways. To characterize the molecular mechanisms involved in controlling cacao flowering time, we have characterized a cacao candidate florigen gene, TcFLOWERING LOCUS T (TcFT). Understanding how this conserved flowering time regulator affects cacao plant’s transition to flowering could lead to strategies to accelerate cacao breeding. Results BLAST searches of cacao genome reference assemblies identified seven candidate members of the CENTRORADIALIS/TERMINAL FLOWER1/SELF PRUNING gene family including a single florigen candidate. cDNA encoding the predicted cacao florigen was cloned and functionally tested by transgenic genetic complementation in the Arabidopsis ft-10 mutant. Transgenic expression of the candidate TcFT cDNA in late flowering Arabidopsis ft-10 partially rescues the mutant to wild-type flowering time. Gene expression studies reveal that TcFT is spatially and temporally expressed in a manner similar to that found in Arabidopsis, specifically, TcFT mRNA is shown to be both developmentally and diurnally regulated in leaves and is most abundant in floral tissues. Finally, to test interspecies compatibility of florigens, we transformed cacao tissues with AtFT resulting in the remarkable formation of flowers in tissue culture. The morphology of these in vitro flowers is normal, and they produce pollen that germinates in vitro with high rates. Conclusion We have identified the cacao CETS gene family, central to developmental regulation in angiosperms. The role of the cacao’s single FT-like gene (TcFT) as a general regulator of determinate growth in cacao was demonstrated by functional complementation of Arabidopsis ft-10 late-flowering mutant and through gene expression analysis. In addition, overexpression of AtFT in cacao resulted in precocious flowering in cacao tissue culture demonstrating the highly conserved function of FT and the mechanisms controlling flowering in cacao.

Flowering responses to vernalization and photoperiod in annual medics (Medicago spp.)

1975 ◽  
Vol 26 (5) ◽  
pp. 831 ◽  
Author(s):  
NM Clarkson ◽  
JS Russell
Keyword(s):  
High Temperature ◽  
Flowering Time ◽  
Vernalization Requirement ◽  
Vernalization Response ◽  
The Third ◽  
Long Day ◽  
Temperature Requirement ◽  
New Finding ◽  
Annual Medics

The three processes thought to control flowering times in annual medics (Medicago spp.) are a vernalization requirement, a long day requirement and a high temperature requirement. To examine the first two processes, seed of seven cultivars of six species was vernalized at 1�C for periods of up to 11 weeks, then grown to flowering under three photoperiods in a glasshouse. To study the third process, the time to flowering of selected treatments from this expcrirnent was compared with flowering data from plants grown in the field at a range of temperatures lower than in the glasshouse. Vernalization and photoperiod caused large shifts in flowering time but the effects varied widely among species. M. scutellata was almost insensitive to both factors but in M. rugosa acceleration of up to 91 days was caused by treatment. Vernalization and short dark periods were additive in accelerating flowering and largely able to substitute for each other. Species flowered almost simultaneously when given their most favourable conditions for flowering. High temperature accelerated flowering in all species studied. However, in species other than M. scutellata it was necessary for a vernalization requirement to be met before this effect was observed. A new finding was that the vernalization response in M. truncatula and M. littoralis was largely reversed after more than 7 weeks of vernalization. This suggests a previously undetected flowering mechanism in these species.

The effect of leaf removal on flowering time in subterranean clover

1970 ◽  
Vol 21 (6) ◽  
pp. 893 ◽  
Author(s):  
WJ Collins ◽  
Y Aitken
Keyword(s):  
Flowering Time ◽  
Subterranean Clover ◽  
Early Growth ◽  
Grazing Management ◽  
Flower Initiation ◽  
Leaf Removal ◽  
Main Shoot ◽  
Delayed Flowering ◽  
Leaf Appearance ◽  
Rate Of Leaf Appearance

The removal of fully expanded leaves delayed flowering by up to 30 days in subterranean clover cv. Mt. Barker sown in winter at Melbourne (38�S.). This effect on flowering was attributable partly to a delay in flower initiation and partly to a slower rate of leaf appearance after flower initiation. Thus leaf removal may be added to the factors already known to influence flower initiation in subterranean clover. When plants were grown under a 24 hr photoperiod. leaf removal had no effect on flower initiation; the slight delay that leaf removal caused in flowering was therefore due entirely to its effect in reducing the rate of leaf appearance. In other experiments leaf removal delayed the time of flower initiation but had no effect on the rate of leaf appearance. The effect of leaf removal on the time of flowering on the main shoot in lateral-dominant plants (as occur in the field) was qualitatively the same as in plants from which the laterals had been removed. Grazing management of subterranean clover which results in severe defoliation during early growth may delay flowering to such an extent that seed production is reduced substantially, and persistence thereby prejudiced.

Flowering time and the natural distribution and dry matter production of Townsville lucerne (Stylosanthes humilis) populations

1967 ◽  
Vol 7 (29) ◽  
pp. 501 ◽  
Author(s):  
DF Cameron
Keyword(s):  
Flowering Time ◽  
Dry Matter ◽  
Growth Habit ◽  
Correlation Coefficients ◽  
Annual Rainfall ◽  
Late Flowering ◽  
Matter Production ◽  
Northern Areas ◽  
Stylosanthes Humilis ◽  
Significant Yield

The flowering times of 58 collections of Townsville lucerne from typical sites in northern Australia have been recorded in three spaced plant experiments near Townsville. Thirty-six collections were grown in 1963-64, 15 in 1964-65, and 17 in 1965-66. All the late flowering collections came from sites receiving at least 45 inches annual rainfall. The five collections from south of Rockhampton were all of the early or midseason type and all collections from the far northern areas were late flowering. Partial regression analysis was used to relate the flowering time of a collection to the rainfall (for the five months interval from January to May) and latitude of the collection site. In the first two experiments rainfall, latitude and (latitude)2 all contributed significantly to the regressions, but in the third experiment only rainfall was significant. Correlation coefficients for 1963-64, 1964-65, and 1965-66 were +0.83, +0.97, and +0.93 respectively. A selection was derived from a collection by bulking seed from single spaced plants selected for uniform flowering time and growth habit. The dry matter yields of some collections and selections were compared in two sward experiments near Townsville in 1964-65 and 1965-66. In 1964-65 there were significant yield differences between collections (experiment A, P<0.01) and between selections (experiment B, P<0.001). There were differences in the rates of vegetative growth and differences in the length of growing season, with late flowering types being able to make better growth late in the season when early types were flowering and seeding. Types with erect growth habit had the highest yields and seemed to compete better with sown grasses than the prostrate types. There were no significant yield differences in 1965-66, a very dry year, and the late flowering types failed to set seed.

scholarly journals Overexpression of AtAHL20 causes delayed flowering in Arabidopsis via repression of FT expression

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Reuben Tayengwa ◽  
Pushpa Sharma Koirala ◽  
Courtney F. Pierce ◽  
Breanna E. Werner ◽  
Michael M. Neff
Keyword(s):  
Transgenic Plants ◽  
Gene Family ◽  
Flowering Time ◽  
Camelina Sativa ◽  
Negative Regulator ◽  
Peptide Sequence ◽  
Type I ◽  
Mrna Levels ◽  
Core Motif ◽  
Late Flowering

Abstract Background The 29-member Arabidopsis AHL gene family is classified into three main classes based on nucleotide and protein sequence evolutionary differences. These differences include the presence or absence of introns, type and/or number of conserved AT-hook and PPC domains. AHL gene family members are divided into two phylogenetic clades, Clade-A and Clade-B. A majority of the 29 members remain functionally uncharacterized. Furthermore, the biological significance of the DNA and peptide sequence diversity, observed in the conserved motifs and domains found in the different AHL types, is a subject area that remains largely unexplored. Results Transgenic plants overexpressing AtAHL20 flowered later than the wild type under both short and long days. Transcript accumulation analyses showed that 35S:AtAHL20 plants contained reduced FT, TSF, AGL8 and SPL3 mRNA levels. Similarly, overexpression of AtAHL20’s orthologue in Camelina sativa, Arabidopsis’ closely related Brassicaceae family member species, conferred a late-flowering phenotype via suppression of CsFT expression. However, overexpression of an aberrant AtAHL20 gene harboring a missense mutation in the AT-hook domain’s highly conserved R-G-R core motif abolished the late-flowering phenotype. Data from targeted yeast-two-hybrid assays showed that AtAHL20 interacted with itself and several other Clade-A Type-I AHLs which have been previously implicated in flowering-time regulation: AtAHL19, AtAHL22 and AtAHL29. Conclusion We showed via gain-of-function analysis that AtAHL20 is a negative regulator of FT expression, as well as other downstream flowering time regulating genes. A similar outcome in Camelina sativa transgenic plants overexpressing CsAHL20 suggest that this is a conserved function. Our results demonstrate that AtAHL20 acts as a photoperiod-independent negative regulator of transition to flowering.

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