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

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).

1969 ◽  
Vol 20 (6) ◽  
pp. 1043 ◽  
Author(s):  
RC Rossiter

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.


1955 ◽  
Vol 6 (5) ◽  
pp. 673 ◽  
Author(s):  
KD McLachlan

Subterranean clover (Trifolium subterraneum L.) was grown on 32 virgin soils in pot cultures, and the yield responses to phosphorus, sulphur, and molybdenum were determined for each soil. The soils were collected from a wide area in eastern Australia, extending from south-western Victoria to southern Queensland. Sulphur deficiency occurred almost as frequently as phosphorus deficiency. In fact, 75 per cent. of the soils were deficient in both phosphorus and sulphur. Thirty-one per cent. were deficient in all three elements. The effect of the interaction between the elements on the occurrence and intensity of the deficiencies is shown. Molybdenum responses were obtained only after the other deficiencies had been corrected. A deficiency in one of the elements is no indication of deficiency or sufficiency of either of the other two. There was no correlation between the occurrence or intensity of the deficiencies and the geological origin of the soil parent material, the climate of the regions from which the soils were collected, or such soil characters as colour, organic matter, and texture. Responses to phosphorus were less on the black earths than on the red or yellow podzolic soils; those on the red earths were intermediate. The intensity of sulphur deficiency increased, and the intensity of molybdenum deficiency decreased, with increasing soil pH.


1967 ◽  
Vol 18 (1) ◽  
pp. 23 ◽  
Author(s):  
RC Rossiter ◽  
AB Beck

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".


2003 ◽  
Vol 54 (2) ◽  
pp. 203 ◽  
Author(s):  
B. S. Dear ◽  
G. A. Sandral ◽  
D. Spencer ◽  
M. R. I. Khan ◽  
T. J. V. Higgins

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.


1966 ◽  
Vol 17 (1) ◽  
pp. 29 ◽  
Author(s):  
RC Rossiter ◽  
AB Beck

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".


1967 ◽  
Vol 18 (4) ◽  
pp. 561 ◽  
Author(s):  
RC Rossiter ◽  
AB Beck

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.


1970 ◽  
Vol 21 (4) ◽  
pp. 593 ◽  
Author(s):  
RC Rossiter

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.


1966 ◽  
Vol 17 (4) ◽  
pp. 447 ◽  
Author(s):  
RC Rossiter ◽  
AB Beck

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.


1964 ◽  
Vol 15 (4) ◽  
pp. 527 ◽  
Author(s):  
AJ Millington ◽  
CM Francis ◽  
NR McKeown

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.


2016 ◽  
Vol 23 (5) ◽  
pp. 1111-1131 ◽  
Author(s):  
AbdulLateef Olanrewaju

Purpose – The opportunities that the emerging markets present to the players in the construction industry means that the players need to expand on the scope and size of their responsibilities and duties to the stakeholders. Each of the professionals now demands more specialised and sophisticated services from one another. The other players in the construction industry now require more emerging responsibilities and duties from the quantity surveyors. The purpose of this paper is to examine the roles that “modern” quantity surveyors play by measuring the gaps that exist in the services that the quantity surveyors provide. Design/methodology/approach – Primary data are collected through survey questionnaires. In total, 23 roles played by modern quantity surveyors are identified and addressed to the respondents to rank the rate at which quantity surveyors provide these “emerging” services. The collected data were analysed statistically. Findings – The results of the findings led to the conclusion that the quantity surveyors were not meeting the expectations of other players. Therefore, for competitiveness, quantity surveyors need to better meet demand expectations. Research limitations/implications – This findings of this research are constrained to the services or functions that the quantity provide in the construction industry. Practical implications – This knowledge is valuable to academic institutions that offer quantity surveying programmes, to practicing quantity surveyors, governments, and other players in the construction industry. It will allow quantity surveyors to reconcile supply and demand expectations. Originality/value – There is no known conclusive empirical study on services offered by quantity surveyors in any emerging markets. Therefore, the findings offer a fresh understanding on the services of quantity surveyors not only in Nigeria but elsewhere. While some of the services are common, others are peculiar to emerging markets.


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