Physiological and ecological studies on the oestrogenic isoflavones in subterranean clover (T. subterraneum L.) VII. Effects of nitrogen supply

1969 ◽  
Vol 20 (6) ◽  
pp. 1043 ◽  
Author(s):  
RC Rossiter
Keyword(s):  
Protein Synthesis ◽  
Nitrogen Deficiency ◽  
Subterranean Clover ◽  
Nitrogen Supply ◽  
The Other ◽  
Biochanin A ◽  
Ecological Studies ◽  
Carbon Substrates ◽  
Low Nitrogen ◽  
Practical Implications

In experiments with young plants of the Dwalganup strain of subterranean clover, nitrogen deficiency was associated with increased concentrations of isoflavones in the expanded leaves and cotyledons. In the first trifoliate leaves the concentration of total isoflavones (formononetin+genistein+ biochanin A) was approximately doubled at low nitrogen supply. Biochanin A was much less affected than the other two isoflavones. The increase in isoflavone contents of nitrogen-deficient leaves was associated with decreased protein synthesis, but not always with increased sugar contents. The supply of carbon substrates for isoflavone synthesis may depend on starch as well as sugar contents. Practical implications of the results are considered briefly.

Physiological and ecological studies on the oestrogenic isoflavones in subterranean clover (T. subterraneum L.). IX.* Effects of sulphur supply

1972 ◽  
Vol 23 (3) ◽  
pp. 411 ◽  
Author(s):  
RC Rossiter ◽  
NJ Barrow
Keyword(s):  
Subterranean Clover ◽  
The Other ◽  
Biochanin A ◽  
Ecological Studies ◽  
Sulphur Deficiency ◽  
Severe Deficiency ◽  
Practical Implications

The results of field and glasshouse experiments showed that sulphur deficiency increased isoflavone concentrations in clover leaves. Severe deficiency almost doubled the concentration of total isoflavones (formononetin + genistein f biochanin A). Usually formononetin was affected as much as, or more than, either of the other two isoflavones. Four clover strains—Dwalganup, Geraldton, Daliak, and Yarloop—which differed widely in their isoflavone concentrations did not differ significantly in their proportionate increases in isoflavone concentrations due to severe sulphur deficiency. Practical implications of the results are considered briefly. __________________ *Part VIII, Aust. J. Agric. Res., 21: 593 (1970).

Physiological and ecological studies on the oestrogenic isoflavones in subterranean clover, (T. subterraneum L.) VIII. Phosphate supply in relation to temperature and to leaf development

1970 ◽  
Vol 21 (4) ◽  
pp. 593 ◽  
Author(s):  
RC Rossiter
Keyword(s):  
Leaf Growth ◽  
Subterranean Clover ◽  
Relative Difference ◽  
Biochanin A ◽  
Leaf Cell ◽  
Ecological Studies ◽  
Leaf Emergence ◽  
Carbon Substrates ◽  
Phosphate Supply ◽  
High Phosphate

In recently expanded first trifoliate leaves of the Dwalganup strain of subterranean clover, the relative difference for concentrations of formononetin at low and high phosphate supply levels was about the same at 12.5, 22.5, and 32.5�C. However, absolute differences were much less at the high temperature, where concentrations were also low. The concentrations of the other isoflavones, genistein and biochanin A, were much less affected by phosphate supply than was formononetin. Effects of phosphate on isoflavone concentrations were already evident at leaf emergence; and in phosphate-deficient leaves, concentrations of isoflavones - especially formononetin - increased during the later stages of leaf growth. Isoflavone production per leaf cell seems to be dependent on the supply of carbon substrates in the form of sugars and starch.

Physiological and ecological studies on the oestrogenic isoflavones in subterranean clover (T. subterraneum L.). II. Effects of phosphate supply

1966 ◽  
Vol 17 (4) ◽  
pp. 447 ◽  
Author(s):  
RC Rossiter ◽  
AB Beck
Keyword(s):  
Subterranean Clover ◽  
Dry Weight ◽  
Biochanin A ◽  
Phosphate Deficiency ◽  
Ecological Studies ◽  
Carbon Substrates ◽  
Phosphate Supply ◽  
Total Dry Weight

Two experiments with the Mt. Barker strain of subterranean clover and one with the Dwalganup strain were conducted. In each experiment, increase in phosphate supply led to increases in total dry weight production. As phosphate deficiency became more acute in the Dwalganup strain, the leaf concentrations of two isoflavones, formononetin and genistein, increased as much as twofold; a third isoflavone, biochanin A, showed little change. In the Mt. Barker strain the concentrations of genistein and biochanin A increased about twofold with increasing severity of phosphate deficiency, while those of formononetin increased at least fourfold. It is suggested that isoflavone formation in clover leaves increases under phosphate deficiency, and that this is associated with increased carbon substrates in the leaf cells. The relations between isoflavone levels and oestrogenic potency are discussed. Phosphate deficiency may be indirectly related to oestrogenic potency through its influence on isoflavone levels.

Physiological and ecological studies on the oestrogenic isoflavones in subterranean clover (T. subterraneum L.) III. Effects of light

1967 ◽  
Vol 18 (1) ◽  
pp. 23 ◽  
Author(s):  
RC Rossiter ◽  
AB Beck
Keyword(s):  
Light Intensity ◽  
Subterranean Clover ◽  
Substantial Effect ◽  
The Other ◽  
Light Environment ◽  
Natural Light ◽  
Ecological Studies ◽  
Other Hand ◽  
Isoflavone Content ◽  
Per Se

Isoflavone levels in subterranean clover leaves were higher in 13 hr days of natural daylight than in 6 hr days, but length of photoperiod per se had no substantial effect on these levels. In the field, reduction of light intensity (by shading) to 40% daylight caused no decline in isoflavone levels compared with full daylight; even at 24% daylight the reduction in levels was ill defined. On the other hand, in young seedlings there was a marked fall in isoflavone content, especially in the unifoliate leaf, as light intensity fell from 950 to 320 f.c. However, appreciable isoflavone formation was found in dark-grown clover seedlings. Possible light reactions connected with the promotion of isoflavone synthesis are discussed. Changes in isoflavone levels resulting from variation in the natural light environment are unlikely to be sufficient to affect "clover disease".

The tolerance of three transgenic subterranean clover (Trifolium subterraneum L.) lines with the bxn gene to herbicides containing bromoxynil

2003 ◽  
Vol 54 (2) ◽  
pp. 203 ◽  
Author(s):  
B. S. Dear ◽  
G. A. Sandral ◽  
D. Spencer ◽  
M. R. I. Khan ◽  
T. J. V. Higgins
Keyword(s):  
Leaf Area ◽  
Seed Yield ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
The Other ◽  
Biochanin A ◽  
Leaf Stage ◽  
Agronomic Characteristics ◽  
Herbage Yield ◽  
Transgenic Lines

A bxn gene, coding for the nitilase enzyme that catalyses the detoxification of the herbicide bromoxynil, was inserted into subterranean clover (Trifolium subterraneum L. subsp. yanninicum). The agronomic characteristics of 3 transgenic lines (BXN 5, 7, 10) and their response to herbicides containing bromoxynil, were compared with that of the non-transgenic parent, cv. Gosse, in 1 glasshouse and 2 field experiments.The application of bromoxynil at 1.5 L/ha resulted in a 50% reduction in the spring herbage yield of the non-transgenic control but no reduction in BXN 5 and 7. The level of the phyto-oestrogens, genistein and biochanin A, in the leaf tissue were low in Gosse and the 2 transgenic lines, BXN 7 and 10, but the level of genistein increased significantly (P < 0.05) from 0.85% in Gosse to 1.43% dry weight in BXN 5, and biochanin A increased from 0.35% in Gosse to 0.73% in BXN 5. The application of the herbicides bromoxynil, bromoxynil+MCPA, and Jaguar (bromoxynil+diflufenican) at the cotyledon stage in a glasshouse study significantly reduced the leaf area of the non-transgenic Gosse, but did not reduce the leaf area of the 3 transgenic lines. When applied at the 4–5 leaf stage, the leaf area of Gosse was again reduced by all the herbicides, but only the bromoxynil+MCPA treatment reduced the leaf area of the transgenic lines relative to the control. The application of bromoxynil or Jaguar at the 4–5 leaf stage depressed the herbage yield of Gosse by about 62% compared with 0–24% in the 3 transgenic lines. In the field studies, BXN 5 and 10 had similar seed yields to Gosse in the absence of herbicide application, but the seed yield of BXN 7 was significantly less than the other 2 transgenic lines. The level of hard-seed in BXN 7 was also lower at 25% compared with 55–57% in the other transgenic lines and Gosse.These findings stress the need to carefully assess the agronomic qualities of transgenic lines prior to release as although tolerance to bromoxynil may be greatly increased by the bxn gene, other important agronomic characteristics, such as seed yield, hardseededness, and isoflavone content, may change as result of the gene or transformation process.

Physiological and ecological studies on the oestrogenic isoflavones in subterranean clover (T. subterraneum L.) I. Effects of temperature

1966 ◽  
Vol 17 (1) ◽  
pp. 29 ◽  
Author(s):  
RC Rossiter ◽  
AB Beck
Keyword(s):  
Total Concentration ◽  
Subterranean Clover ◽  
Maximum Growth ◽  
Biochanin A ◽  
Ecological Studies ◽  
Leaf Material ◽  
Long Day ◽  
Effects Of Temperature

Two strains of subterranean clover – Yarloop and Mt. Barker – were grown at controlled temperatures ranging from 36/31° to 9/4°C under long-day conditions. Leaf material was analysed for the three isoflavones formononetin, genistein, and biochanin A. In the Mt. Barker strain, the formononetin concentration was low (< 0.2% dry wt.) and varied little with temperature. Otherwise, isoflavone levels generally rose from very low values at 36/31° to a peak at 15/10°, and then decreased again to 9/4°. For both strains the total concentration of the three isoflavones and also the total amount of isoflavones per leaf were highest at 15/10°. This temperature was lower than that at which maximum growth occurred. The data are discussed in relation to evidence on the effects of temperature on the formation of flavonoid (especially anthocyanin) compounds. We conclude that temperature is unlikely to be a major factor in the incidence of "clover disease".

Physiological and ecological studies on the oestrogenic isoflavones in subterranean clover (T. subterraneum L.) V. Ontogenetic change

1967 ◽  
Vol 18 (4) ◽  
pp. 561 ◽  
Author(s):  
RC Rossiter ◽  
AB Beck
Keyword(s):  
Age Differences ◽  
Cell Expansion ◽  
Leaf Age ◽  
Subterranean Clover ◽  
Biochanin A ◽  
Ontogenetic Change ◽  
Ecological Studies ◽  
Expansion Stage ◽  
Low Levels ◽  
The Individual

On plants of the same age, differences between leaves in the concentrations of the oestrogenic isoflavones daidzein (D), formononetin (F), genistein (G), and biochanin A (BA) were largely due to differences in leaf age. Concentrations of F, G, and BA declined during unfolding and development of the individual leaf. The maximum amounts per leaf of F, G, and BA were attained at the completion of the cell expansion stage. The appearance of D was associated with leaf senescence. The concentrations of F, G, and BA in expanded leaves usually declined during plant growth. An exception was F in the Yarloop strain. Relatively low levels of isoflavones were found in the stem + petiole fraction and in the roots, and intermediate levels in flowers. The relevance of these results to animal bioassays for oestrogenic activity is discussed.

The comparative phosphate requirements of four annual pastures and two crops

1976 ◽  
Vol 27 (4) ◽  
pp. 479 ◽  
Author(s):  
PG Ozanne ◽  
KMW Howes ◽  
A Petch
Keyword(s):  
Unit Area ◽  
Maximum Yield ◽  
Subterranean Clover ◽  
Single Species ◽  
Nitrogen Supply ◽  
High Nitrogen ◽  
Direct Response ◽  
Phosphorus Requirement ◽  
Wimmera Ryegrass ◽  
Low Nitrogen

The levels of broadcast phosphate needed for 90% of maximum production by subterranean clover, Wimmera ryegrass at two levels of nitrogen, wheat and lupins are compared in a field experiment. Two seeding rates, one five times the other, were used to vary the stand densities and yields per unit area of the swards. A total of 180 kg nitrogen/ha was supplied to the wheat and high nitrogen grass plots; the low nitrogen grass plots received 30 kg/ha. Although both the high seeding rates and the high nitrogen applications gave up to double the yield per unit area, they did not significantly change the level of phosphate required for 90% of maximum yield by a given species or mixture. Grown as single species, lupins had the highest phosphorus requirement (202 kg/ha); wheat (118 kg/ha) and clover (107 kg/ha) had similar requirements; while grass with either a low nitrogen supply (58 kg/ha) or a high nitrogen supply (56 kg/ha) had the lowest requirement when measured during flowering. When clover and ryegrass were grown as a mixed sward, the phosphorus requirement (84 kg/ha) was close to the average of those for the pure clover and grass. Both the grass and clover responded to approximately the same level of phosphate when grown as a mixture. The amount of nitrogen fixed by the clover, either as a pure sward or when mixed with grass, increased with increasing phosphate application. We think that the phosphate level required by the grass when grown with clover rather than as a pure sward was an expression of this increased nitrogen supply and not a direct response to phosphate. The levels of phosphate required to produce 90% of the maximum grain yield in the lupin and ear yield in the wheat were similar to the phosphate requirement for 90% of maximum vegetative yield.

Wether bioassay of animal pasture legumes. II. The oestrogenic activity of nine strains of Trifolium subterraneum L.

1964 ◽  
Vol 15 (4) ◽  
pp. 527 ◽  
Author(s):  
AJ Millington ◽  
CM Francis ◽  
NR McKeown
Keyword(s):  
Regression Analysis ◽  
Thin Layer ◽  
Multiple Regression Analysis ◽  
Positive Relationship ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
The Other ◽  
Biochanin A ◽  
Pasture Legumes ◽  
Layer Chromatography

Nine strains of subterranean clover (Trifolium subterraneum L.) were assayed for oestrogenic activity with changes in wether teat length as the criterion. The isoflavone and coumestrol contents of each strain were determined by thin-layer chromatography. Significant differences were obtained between strains. Multiple regression analysis indicated a positive relationship between increase in teat length and the formononetin content of the strains. No such relationship was found for either genistein or biochanin A, the other isoflavones that were present in appreciable amounts.

EFFECT OF ACTINOMYCIN D ON TSH-INDUCED STIMULATION OF THYROIDAL PROTEIN SYNTHESIS IN THE RAT

1974 ◽  
Vol 77 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Gustav Wägar
Keyword(s):  
Protein Synthesis ◽  
Actinomycin D ◽  
The Other ◽  
Leucine Incorporation ◽  
Short Term ◽  
Other Hand ◽  
Thyroid Glands ◽  
Translational Level ◽  
Stimulation Of

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.

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