Diversity for morphological traits, flowering time and leaf isoflavone content among ecotypes of Trifolium subterraneum L. subsp. yanninicum and their relationships with site of origin

2021 ◽  
Author(s):  
Gereltsetseg Enkhbat ◽  
Phillip G H Nichols ◽  
Kevin J Foster ◽  
Megan H Ryan ◽  
Yoshiaki Inukai ◽  
...  
Keyword(s):  
Flowering Time ◽  
Morphological Traits ◽  
Trifolium Subterraneum ◽  
Isoflavone Content

Genetic variation in populations of two Mediterranean annual pasture legumes (Biserrula pelecinus L. and Ornithopus compressus L.) and associated rhizobia

1999 ◽  
Vol 50 (3) ◽  
pp. 303 ◽  
Author(s):  
A. Loi ◽  
J. G. Howieson ◽  
P. S. Cocks ◽  
S. J. Carr
Keyword(s):  
Genetic Variation ◽  
Flowering Time ◽  
Morphological Traits ◽  
Root Nodule ◽  
Dna Analysis ◽  
Phenotypic Variability ◽  
Pcr Amplification ◽  
Nodule Bacteria ◽  
Pasture Legumes ◽  
Ornithopus Compressus

Genetic variation between and within populations of Biserrula pelecinus L. (biserrula) and Ornithopus compressus L. (yellow serradella) and associated rhizobia was studied using germplasm collected from sites in central-eastern and south-eastern Sardinia (Italy). Pods and root-nodule bacteria were collected on diagonal transects at each site. Plants were characterised in nursery rows and the rhizobia were isolated and tested for their effectiveness. Thirteen morphological traits were recorded and the results were analysed using cluster analysis. Genetic and phenotypic variation of rhizobia were assessed using DNA analysis (PCR, RAPDs) and effectiveness indices, respectively. Genetic variation based on morphological traits was found between and within sites for both species. Pod characteristics and flowering time were the most important traits assisting in discriminating between accessions. Flowering time varied more in serradella than in biserrula, particularly at Cantoniera Cannas. Although all rhizobial strains nodulated all accessions of biserrula, great variability in capacity to fix nitrogen was evident between and within sites. Distinct PCR amplification profiles were generated for individual rhizobial strains, which confirmed the phenotypic variability (effectiveness indices) of the strains. No relationship was found between host and rhizobia variation. The results are discussed in terms of (a) genetic differences for each species within and between sites; (b) differences in behaviour in respect to genetic variation between biserrula, serradella, and other Mediterranean annual legumes; and (c) spatial variability and symbiotic effectiveness of rhizobia.

Urinary sediments in sheep feeding on oestrogenic clover. I. Preliminary observations on changes in certain urinary constituents

1970 ◽  
Vol 21 (6) ◽  
pp. 933 ◽  
Author(s):  
WJ Parr ◽  
P Steele ◽  
B Gabbedy ◽  
MC Nottle
Keyword(s):  
Direct Relationship ◽  
Daily Intake ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Urinary Calcium ◽  
Direct Result ◽  
Calcium Excretion ◽  
Total Phenols ◽  
Isoflavone Content ◽  
Daily Excretion

In recent years a series of widespread outbreaks of acute urinary obstruction has occurred in spring in Merino wethers. Animals involved have been grazing oestrogenic strains of subterranean clover at a time when isoflavone concentrations can be expected to be high. Studies have been made on one property on the relationships between these outbreaks, the pasture isoflavone content, and the urinary excretion of phenolic and other constituents by wethers. A trial group of animals was grazed on a dominant sward of the highly oestrogenic Trifolium subterraneum cv. Dinninup during winter and spring. Isoflavone concentrations in the clover reached a peak in early August. However, since the pasture became highly clover-dominant in September and early October the maximum daily intake of isoflavones probably occurred during this period, which also coincided with the occurrence of maximum concentration and maximum daily excretion of total phenols and acid-precipitable material (APM) in the urine. It is suggested that the sediments causing clinical obstructions at this time of the year may be a direct result of increased excretion of phenols. APM showed a highly significant direct relationship with total phenols but its excretion increased at a greater rate than did that of phenols. Urinary calcium excretion also increased at the same time.

Novel Disease Host Resistances in the World Core Collection of Trifolium subterraneum

Plant Disease ◽  
2020 ◽  
Author(s):  
Ming Pei You ◽  
Phillip Nichols ◽  
Roseline Katusiime ◽  
Martin John BARBETTI
Keyword(s):  
Core Collection ◽  
Morphological Traits ◽  
Phenotypic Expression ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Damping Off ◽  
Pythium Irregulare ◽  
Breeding Programs ◽  
Foliar Diseases ◽  
Disease Parameters

Glasshouse and field investigations were undertaken into the phenotypic expressions of resistance of a 97-member World Core Collection of subterranean clover (Trifolium subterraneum), collected from its native Mediterranean habitat and representing around 80% of the total genetic diversity within the known 10,000 accessions of the species, against the most important damping-off and root rot (Phytophthora clandestina, and Pythium irregulare) and foliar (Kabatiella caulivora, Uromyces trifolii-repentis and Erysiphe trifoliorum)pathogens. An additional 28 diverse cultivars were also included. Associations were also examined for these genotypes between 18 disease parameters and 17 morphological traits and between these disease parameters and 24 climatic and eco-geographic variables from their collection sites. Many genotypes showed strong phenotypic expression of novel host disease resistance(s) against one or more pathogens, enabling their potential deployment as disease resistant parents into subterranean clover breeding programs. These new sources of resistance enable future ‘pyramiding’ of different resistance genes to improve resistance against these pathogens. Of particular value were genotypes with multiple disease resistances across soilborne and/or foliar diseases, as many of these pathogens co-occur. All diseases had some parameters significantly correlated with one or more morphological traits and with one or more site of origin variables. In particular, there were significant negative correlations between damping-off (i.e., germination) and eight of the 17 morphological characters. The outcome of these studies provides crucial information to subterranean clover breeding programs, enabling them to simultaneously select genotypes with multiple resistances to co-occurring soilborne and foliar diseases, in addition to desirable traits, to offer renewed hope for re-establishing a more productive subterranean clover livestock feedbase despite multiple diseases prevailing widely.

Flowering time in subterranean clover

1956 ◽  
Vol 7 (5) ◽  
pp. 388 ◽  
Author(s):  
FHW Morley ◽  
CI Davern
Keyword(s):  
Plant Breeding ◽  
Flowering Time ◽  
Natural Habitat ◽  
Strain Differences ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Relative Importance

Genotype-environment interactions have been observed in the flowering times of a number of varieties of subterranean clover (Trifolium subterraneum L.) grown in different locations. These interactions are interpreted in terms of the effects of photoperiod and temperature on flowering. Sensitivity to photoperiod may be independent of sensitivity to temperature. Flowering times of some strains, although simultaneous in one environment, may differ in another environment. This is due to variation in the relative importance of different components of the environment in controlling flowering time. These strain differences in flowering-time physiology are shown to be related to the climate of the strain's natural habitat. The importance of a knowledge of flowering physiology, and the recognition of the existence of genotype - environment interactions, are discussed in relation to plant breeding and introduction.

The inheritance of flowering time in Trifolium subterraneum L

1957 ◽  
Vol 8 (2) ◽  
pp. 121 ◽  
Author(s):  
CI Davern ◽  
JW Peak ◽  
FHW Morley
Keyword(s):  
Genetic Variation ◽  
Flowering Time ◽  
Intraclass Correlation ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Diallel Analysis ◽  
Genetic Effects ◽  
Breeding Behaviour ◽  
Variable Factor ◽  
Additive Genetic Effects

The inheritance of flowering time in subterranean clover, using a number of strains and hybrids among them, was investigated on autumn-sown material at Canberra. Heterosis and dominance were not found, and genetic variation was polygenic. An F1 diallel analysis and F2 two-way analysis showed that approximately 90 per cent. of the total variance was attributable to additive genetic effects. An estimate of the repeatability of strain performance over two seasons showed that small but significant strain-year interactions were occurring. Strain repeatability, as measured by intraclass correlation, was 86 per cent. A breeding test involving F2 selections and their progeny gave a mean parent-offspring regression of 0.86 over the six crosses studied, which is well in accord with expectations of breeding behaviour based on the above analyses. The results are discussed in relation to other studies on flowering time, especially with reference to the problem of interpreting results based on the threshold expression of a character dependent on the value of a continuously variable factor.

Symbiotic competence of Trifolium subterraneum lines of low oestrogenic isoflavone content

1970 ◽  
Vol 10 (46) ◽  
pp. 555 ◽  
Author(s):  
J Brockwell ◽  
AC Robinson
Keyword(s):  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Rhizobium Trifolii ◽  
Isoflavone Content ◽  
Low Levels ◽  
Better Than

Twenty-nine lines of subterranean clover (Trifolium subterraneum), mostly selected for low levels of oestrogenic isoflavones, were inoculated with seven effective strains of Rhizobium trifolii. They were grown at two different root temperatures and their performances compared with those of the subterraneum clover cultivar, Tallarook. Ten criteria were used to assess symbiotic competence. No line was inferior to Tallarook in all ten criteria, but one line was inferior in nine of the ten, three in seven of the ten and fifteen others were poorer than Tallarook in one to six criteria. Of the ten lines whose symbiotic performances were as good as or better than Tallarook, a number also had low isoflavone levels, but there was no evidence to suggest that symbiotic competence was related to isoflavone content. It is concluded that it will be necessary to exercise caution in the agronomic or breeding use of lines Which are not consistently symbiotically competent.

The effect of waterlogging on the growth and isoflavone concentration of Trifolium subterraneum L.

1969 ◽  
Vol 20 (5) ◽  
pp. 819 ◽  
Author(s):  
CM Francis ◽  
AC Devitt
Keyword(s):  
Plant Growth ◽  
Root Growth ◽  
Shoot Growth ◽  
Trifolium Subterraneum ◽  
Relative Increase ◽  
General Increase ◽  
Isoflavone Content ◽  
Relative Tolerance ◽  
Isoflavone Concentration

Seventy-five cultivars were used to determine the effect of waterlogging on the yield and isoflavone content of three subspecies of Trifolium subterraneum L. The 21-day flooding treatment affected root growth more than shoot growth. The relative tolerance of the subspecies to waterlogging was yanninicum > subterraneum > brachycalycinurn. These results were in keeping with ecological evidence. The flooding treatment resulted in a general increase in leaf isoflavone concentrations. As with plant growth there was a significant subspecies x waterlogging interaction, the relative increase in isoflavone concentration being least for subsp. yanninicum.

Evolution in sown populations of subterranean clover (Trifolium subterraneum L. ) in South Australia

1992 ◽  
Vol 43 (7) ◽  
pp. 1583 ◽  
Author(s):  
PS Cocks
Keyword(s):  
Natural Selection ◽  
Flowering Time ◽  
Mediterranean Basin ◽  
South Australia ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Sole Source ◽  
Selection For ◽  
The Mediterranean ◽  
The Mediterranean Basin

The seed banks of three pastures at Kingscote, Parndana and Waterloo, S.A., were sampled to determine the frequency of divergent genotypes in subterranean clover, and the direction of natural selection. The seeds were grown in nursery rows at Adelaide, and the resulting plants classified into one of the commercial cultivars, or as divergent genotypes. The divergent genotypes from one locality, Kingscote, were described in terms of 17 variables, and compared with strains collected from southern Australia and the Mediterranean basin. At each locality there was more genetic diversity than had been sown, both in terms of additional cultivars and the presence of divergent genotypes. The percentage of divergent genotypes appeared to be proportional to the age of the pasture, and was greatest at Kingscote, where it reached 67% of the population. The Kingscote genotypes were genetically related to Mt Barker and Dwalganup, only five out of 283 genotypes having leaf markings that differed from both cultivars. The 17 variables fell between the values recorded for Mt Barker and Dwalganup, and there was evidence of directional selection. For example, formononetin content was less, and genistein more than would be expected in the absence of natural selection. Mean flowering time was about equal to that of Seaton Park, and closer to Mt Barker than to Dwalganup. Flowering time was related to elevation above the lowest point in the paddock, the latest genotypes tending to inhabit sites at the foots of slopes, and the earliest genotypes sites on the tops. Seed and burr weight were slightly larger than expected. Hybridization was the most important, but not the sole source of genetic divergence at Kingscote, whereas contamination was the main source at Waterloo. It is likely that only a minority of the divergent genotypes was generated by mutation. The Australian subterranean clovers were as diverse as those from the Mediterranean. Those from Kingscote were also diverse, but, on the whole, had longer peduncles, shorter internodes and were taller than strains from other parts of Australia and from the Mediterranean basin.

Variation in root morphology and P acquisition efficiency among Trifolium subterraneum genotypes

2019 ◽  
Vol 70 (11) ◽  
pp. 1015 ◽  
Author(s):  
Jonathan W. McLachlan ◽  
Rebecca E. Haling ◽  
Richard J. Simpson ◽  
Xiaoxi Li ◽  
Richard J. Flavel ◽  
...  
Keyword(s):  
Root Hair ◽  
Root Length ◽  
Morphological Traits ◽  
Trifolium Subterraneum ◽  
P Uptake ◽  
Hair Length ◽  
Root Hair Length ◽  
P Acquisition ◽  
Plant P Uptake ◽  
Total Plant

Trifolium subterraneum L. is widely grown in the phosphorus (P) deficient soils of southern Australia. However, this pasture legume has a high critical external P requirement and requires frequent applications of P fertiliser to achieve high productivity. Twenty-six genotypes of T. subterraneum were grown to determine: (i) differences in shoot growth and P acquisition under low-P supply; (ii) the root morphological traits important for P acquisition; and (iii) the feasibility of selection among genotypes for these root morphological traits. Micro-swards of each genotype were grown with a topsoil layer that was either moderately P-deficient or had P supplied in excess of the critical requirement for maximum yield; the subsoil layer was P-deficient. Yield and P content of shoots and roots were determined after 5 weeks’ growth, and root samples were assessed for diameter, length and root hair length. All genotypes were equally highly productive when excess P was supplied. However, relative shoot yield in the moderately P-deficient soil ranged from 38–71%. Total root length ranged from 63–129 m pot–1, and was correlated with total plant P uptake (R2 = 0.78, P < 0.001). Variation was also observed in average root diameter (0.29–0.36 mm) and root hair length (0.19–0.33 mm). These traits were combined with root length to calculate the total surface area of the root hair cylinder, which was also correlated with total plant P uptake (R2 = 0.69, P < 0.001). The results demonstrated that there was significant variation in P acquisition efficiency and shoot yield among genotypes of T. subterraneum when grown in P-deficient soil, and that root length was important for improved P uptake. The results indicate potential to identify superior genotypes that achieve improved P acquisition and higher shoot yields in low-P soil.

Sign in / Sign up

Export Citation Format

Share Document