The effect of sodium on potassium nutrition and ionic relations in Rhodes grass

1974 ◽  
Vol 25 (3) ◽  
pp. 407 ◽  
Author(s):  
FW Smith
Keyword(s):  
Dry Matter ◽  
Potassium Concentration ◽  
Maximum Yield ◽  
Dry Weight ◽  
Maximum Growth ◽  
Major Elements ◽  
Potassium Nutrition ◽  
Rhodes Grass ◽  
Pot Trials ◽  
Chloris Gayana

The effects of sodium on the response of Rhodes grass (Chloris gayana) to potassium have been studied in pot trials. The amount of potassium required to achieve maximum growth was progressively reduced as the level of sodium application was increased from 0 to 400 mg per pot. The concentration of potassium in the tops of plants growing at 95% of maximum yield was also progressively reduced from 2.7% in plants not fertilized with sodium to 0.5% in plants receiving 400 mg sodium per pot. It is concluded that such interactions between the levels of major elements preclude the use of a 'critical potassium level' for diagnosing potassium deficiency in Rhodes grass. An alternative diagnostic scheme which takes account of interactions between some of the major elements is suggested. This scheme requires that plants would be adequately supplied with potassium if two criteria were met simultaneously: the potassium concentration was above the minimum specifically required (0.5% of the dry matter for Rhodes grass) and the cation-anion balance was above a minimum level characteristic for that particular species (800 m-equiv./kg dry weight for Rhodes grass).

Growth, Nodulation and Nitrogen Fixation in Stylosanthes: Effect of Different Root Temperatures at two Shoot Temperatures

1989 ◽  
Vol 25 (4) ◽  
pp. 447-460 ◽  
Author(s):  
R. A. Date ◽  
D. Ratcliff
Keyword(s):  
Nitrogen Fixation ◽  
Dry Matter ◽  
Maximum Yield ◽  
Dry Weight ◽  
Strong Interactions ◽  
Root Temperature ◽  
Relative Growth ◽  
Stylosanthes Hamata ◽  
Nitrogen Yields ◽  
Controlled Environments

SUMMARYNodulated plants of Stylosanthes hamata, S. guianensis, S. humilis, S. scabra and S. fruticosa were grown in controlled environments with varied root and shoot temperatures. Measurement of dry matter and nitrogen content suggested that shoot temperature may be more important than root temperature in controlling growth and nitrogen fixation. There were strong interactions with variety. A fall in relative growth rate with increase in shoot temperature was least for S. guianensis and greatest for S. hamata and S. scabra. The optimum root temperature for growth and nitrogen fixation was approximately 30°C. Ninety percent maximum yield was achieved between root temperatures of 15–36°C for growth and 23–34°C for nitrogen fixation but varied with variety. Nitrogen fixation was more sensitive than dry weight to root temperature. The pattern of response of percentage nitrogen and nitrogen fixation efficiency reflected those for dry weight and nitrogen yields. Shoot to root ratios decreased toward the optimum root temperature then increased at the highest temperature. The reaction of varieties to root and shoot temperatures may be an important factor in determining their suitability for new regions.

Mineral requirements for the growth of Anabaena spiroides in vitro

1968 ◽  
Vol 46 (5) ◽  
pp. 619-630 ◽  
Author(s):  
Sherry L. Volk ◽  
Harry K. Phinney
Keyword(s):  
Dry Weight ◽  
Maximum Growth ◽  
Major Elements ◽  
Major Nutrient ◽  
Initial Culture ◽  
Upper Klamath Lake ◽  
High Concentrations ◽  
Initial Medium ◽  
Klamath Lake

Anabaena spiroides Klebahn, isolated from Upper Klamath Lake, Klamath County, Oregon, was cultured in Gerloff's modification of Chu's number 10 medium. Preliminary to a study of the major nutrient mineral requirements, the initial culture medium was modified by elimination of sodium silicate, the addition of Tris(hydroxymethyl)aminomethane, and the substitution of hydrogen ferric ethylenediamine di-o-hydroxyphenylacetate (EDDHA) for ferric citrate – citric acid.Provision of mineral nitrogen in the medium was found unnecessary for growth, strongly suggesting that A. spiroides can fix nitrogen, but final proof awaits the development of bacteria-free cultures. Although phosphorus was required in relatively high concentrations to obtain maximum growth, it was apparently accumulated in the cells, allowing them to survive long exposure in phosphorus-deficient media. Several other major elements either were required in very minute amounts or were accumulated by the alga. Iron provided in the alkaline-stable chelate EDDHA was required in lower concentration than in Gerloff's medium. A definite, high requirement for calcium was found.A balanced medium was developed that supported an increase of 100% in dry weight, 23% in chlorophyll content, and 10% in organic nitrogen above that obtained in the initial medium.

Productivity of grazed Makarikari grass-lucerne, Rhodes grass-lucerne and lucerne pastures in the northern wheat belt of Australia

1983 ◽  
Vol 23 (123) ◽  
pp. 383 ◽  
Author(s):  
DL Lloyd ◽  
JG Nation ◽  
TB Hilder ◽  
PK O'Rourke
Keyword(s):  
Dry Matter ◽  
Clay Soil ◽  
Stocking Rate ◽  
Rhodes Grass ◽  
Grazing System ◽  
Dry Conditions ◽  
Chloris Gayana ◽  
Stocking Rates ◽  
Grain Farms ◽  
Better Than

Three Makarikari grasses (Panicum coloratum var. makarikariense) viz. 0.4634, cv. Pollock and cv. Bambatsi and Rhodes grass (Chloris gayana) cv. Pioneer, each grown with lucerne (Medicago sativa) cv. Hunter River, and sward lucerne were compared for productivity and stability in a rotational grazing system at three stocking rates (22.2, 14.8 and 7 . 4 Merino wethers/ha for grasslucerne pastures; 14.8, 11.1 and 7.4/ha for lucerne swards) on a cracking clay soil on the Darling Downs, Queensland over four years. There were no differences between the Makarikari grass cvv. Pollock and Bambatsi pastures. However, each produced more dry matter and animal liveweight, and persisted better, than Rhodes grass pasture during dry conditions that occurred during the first two years. Rhodes grass nevertheless recovered during two subsequent wet summers. During those two dry years, wool production from sward lucerne was equal to that of the grass-lucerne pastures at both 14.8 and 7.4 animals/ha. Animal liveweight from lucerne was greater than from grass-lucerne pastures at 7.4 animals/ha only. Wide variation, both between and within seasons, was measured in the quantity of feed produced by pastures in this study. This is discussed in relation to the concept of stocking rate of pasture grown on limited areas of grain farms in the northern wheat belt, and to the provision of a continuing feed supply in integrated crop-pasture systems.

Nitrogen fertilizer responses of pasture grasses in south-eastern Queensland

1963 ◽  
Vol 3 (11) ◽  
pp. 290 ◽  
Author(s):  
EF Henzell
Keyword(s):  
Ammonium Sulphate ◽  
Field Experiments ◽  
Maximum Growth ◽  
Nitrogen Fertilizers ◽  
Nitrogen Recovery ◽  
Residual Effects ◽  
Rhodes Grass ◽  
South Eastern ◽  
Pasture Grasses ◽  
Chloris Gayana

The results are reported of field experiments with nitrogen-fertilized pasture grasses at Samford and D'Aguilar in south-eastern Queensland. The main findings were :- 1. Nitrogen applied as urea or ammonium sulphate increased the annual yield of dry matter under mowing from 1,000- 5,000 lb up to 10,000-20,000 lb an acre, and rates of fertilizer in excess of 400 lb of elemental nitrogen an acre a year were required ,for maximum grass yields during favourable seasons. 2. Ammonium sulphate, applied at rates up to 400 lb N/acre/year, had relatively little effect on the percentage of nitrogen in Rhodes grass (Chloris gayana Kunth.), Paspalum dilatatum Poir., and P. commersonii Lam., cut three times a year. Rates of urea above those required for maximum growth markedly increased the percentage nitrogen content of a Sorghum almum Parodi-blue couch (Digitaria didactyla Willd.) mixture. 3. In an experiment with Rhodes grass, P. dilatatum and P. commersonii, nitrogen recovery rose with increasing rates of ammonium sulphate. At 70 lb N/acre/year the average nitrogen recovery by Rhodes grass was 10 per cent; at 400 lb N/acre/year it was 47 per cent. 4. The residual effects of ammonium sulphate, measured on Rhodes grass during the growing season following two years of fertilization, were very small indeed. 5. Use of nitrogen fertilizers sometimes caused marked changes in the botanical composition of the sward.

Responses of Rhodes Grass and Overseeded Legumes to Nitrogen and Potash Fertilizers and to the Availability of Soil Potassium in Israel

1966 ◽  
Vol 2 (4) ◽  
pp. 255-263 ◽  
Author(s):  
A. Dovrat
Keyword(s):  
Nitrogen Fertilizer ◽  
Dry Matter ◽  
Sandy Loam ◽  
Normal Growth ◽  
Rhodes Grass ◽  
Matter Production ◽  
Potassium Starvation ◽  
Loam Soil ◽  
Chloris Gayana ◽  
Equal Split

SummaryResults are reported from experiments with nitrogen and potash fertilizers in irrigated Rhodes grass (Chloris gayana), into which annual winter legumes, e.g. berseem (Trifolium alexandrinum) and vetch (Vicia sativa) were overseeded. The experiments were carried out over a three year period on a sandy loam soil at Bet Dagan Experimental Farm, Israel. Ammonium sulphate, applied in equal split rates of up to 384 lb N per acre, linearly increased dry matter yields of Rhodes grass, and the increase of yield proportionally increased the uptake of K by harvest. The K content of the dry matter decreased with increasing nitrogen fertilization to 0·47 per cent which, however, was still found sufficient for maintaining maximum production of Rhodes grass. The yield of annual winter legumes decreased proportionally to the amount of nitrogen fertilizer applied during the summer. Acute potassium starvation was observed. An autumn application of potassium chloride restored dry matter production to normal levels. Availability of soil K, expressed in terms of energies of replacement [ΔF(− 1)], decreased proportionally to the amount of nitrogen fertilizer applied. When ΔF reached approximately 4,250 cal/mol, overseeded legumes were K-deficient, whereas Rhodes grass at that value was still able to extinct sufficient K from the soil for normal growth.

scholarly journals Regrowth potential of shoot and of roots of Rhodes grass (Chloris gayana Kunth) after defoliation.

1980 ◽  
Vol 28 (3) ◽  
pp. 185-198
Author(s):  
A. Dovrat ◽  
E. Dayan ◽  
H. van Keulen
Keyword(s):  
Developmental Stage ◽  
Shoot Growth ◽  
Stem Elongation ◽  
Rhodes Grass ◽  
Tropical Grasses ◽  
Constant Rate ◽  
Pot Trials ◽  
Chloris Gayana ◽  
Initial Root ◽  
Chloris Gayana Kunth

In field and pot trials the effect of different lengths of pre-cutting periods and of cutting intervals on regrowth of shoot and of root were studied in Rhodes grass cv. Katambora. The initial regrowth of the sward after a long (28 days) pre-cutting period was slower than after a short (7 days) pre-cutting period. The reduction of the residual LAI following the extension of the pre-cutting period was associated with reduction in the number of tillers capable of regrowth after defoliation. Root wt. decreased drastically following cutting when the initial root wt. was high (long pre-cutting period), but little when the initial root wt. was small (short pre-cutting period). The decrease in root wt. lasted c. 1 wk after which it increased at a more or less constant rate proportional to the increase of shoot wt. irrespective of the length of the pre-cutting period. The lack of the capability of tillers to regrow after cutting was closely related with developmental stage of tillers. Since tillers of subtropical and tropical grasses have a tendency for early stem elongation, it was concluded that the relatively small number of sites available for regrowth in these grasses is the major deterrent for quick shoot growth of the sward after defoliation. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Morphoecological characteristics of grasses used to restore degraded semi-arid African rangelands

2021 ◽  
Author(s):  
Kevin Mganga
Keyword(s):  
Ecological Restoration ◽  
Seed Production ◽  
Dry Matter ◽  
Perennial Grasses ◽  
Grass Species ◽  
Rhodes Grass ◽  
Basal Cover ◽  
Plant Densities ◽  
Chloris Gayana ◽  
Semi Arid

<p>Progressive loss of productivity and plant diversity is a major in global rangelands. In African rangelands ecosystems, this process is partly attributed to heavy and uncontrolled grazing by livestock and wildlife, leading to land degradation. Therefore, restoring such degraded rangelands is critical for enhancing ecosystem health and securing the livelihoods of millions of people. Active restoration strategies, e.g. reseeding using indigenous perennial grasses has been identified as a viable ecological solution for restoring degraded African rangelands. Grass species indigenous to African rangelands Cenchrus ciliaris L. (African foxtail grass), Eragrostis superba Peyr. (Maasai love grass), Enteropogon macrostachyus (Hochst. Ex A. Rich.) Monro ex Benth. (Bush rye grass), Chloris roxburghiana Schult. (Horsetail grass) and Chloris gayana Kunth. cv Boma (Rhodes grass) were established in a semi-arid rangeland in Africa under natural conditions to compare their morphoecological characteristics and suitability for use in ecological restoration. Biomass dry matter yields, plant densities, basal cover, seed production, tiller densities and plant height were measured. Chloris gayana cv Boma and E. superba produced significantly higher dry matter biomass yields and seed production than other species. High biomass and seed production demonstrate their suitability to support livestock production and replenish depleted soil seed banks, respectively. Enteropogon macrostachyus and C. ciliaris displayed significantly higher values for plant densities, tiller densities and basal cover, also a component of establishment and ecological restoration success. Chloris roxburghiana ranked lowest in all the measured morphoecological characteristics. This may be a strong indicator of ecological site-specific characteristic of C. roxburghiana. Successful restoration of degraded African semi-arid rangelands using indigenous grass reseeding can best be achieved through careful selection of grasses to take advantage of their specific morphoecological characteristics. This selection should primarily be informed by the intended use of the rangeland.</p>

scholarly journals The influence of defoliation and nitrogen on the regrowth of Rhodes grass (Chloris gayana Kunth). 1. Dry matter production and tillering.

1971 ◽  
Vol 19 (2) ◽  
pp. 94-101
Author(s):  
A. Dovrat ◽  
G.P. Dirven ◽  
B. Dienum
Keyword(s):  
Dry Matter ◽  
Dry Matter Production ◽  
Root Weight ◽  
N Application ◽  
Rhodes Grass ◽  
Pot Experiments ◽  
Matter Production ◽  
Chloris Gayana ◽  
Shoot Weight ◽  
Chloris Gayana Kunth

In pot experiments Rhodes grass (cv. "Common" and "Katambora") was fertilized with 1.43 and 8.29 meq N/100 g soil over a period of 56 days and was cut every 14 or 28 days. Cutting at 28 days considerably increased total shoot weight. Root weight per pot of low-N plants was 31 and 23% higher than that of high-N plants at 14- and 28-day cutting intervals, respectively. N application generally increased the average number of harvest tillers, but individual tillers regrew a fewer number of times than those receiving low N. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Animal production on sown and native pastures on brigalow land in southern Queensland during drought

1969 ◽  
Vol 9 (36) ◽  
pp. 47 ◽  
Author(s):  
JE Coaldrake ◽  
CA Smith ◽  
JJ Yates ◽  
LA Edye
Keyword(s):  
Dry Matter ◽  
First Year ◽  
Stocking Rate ◽  
Rhodes Grass ◽  
Buffel Grass ◽  
Native Pasture ◽  
Chloris Gayana ◽  
Native Pastures ◽  
Stocking Rates ◽  
Better Than

Liveweight gains of six yearling steers grazing on each of four introduced grasses, each with lucerne, were compared with those from native pasture and native pasture plus forage oats, on a weakly solonized brown clay loam of moderate fertility in the brigalow region of southern Queensland. The pastures were grazed continuously for three years (1963 to 1965) at set stocking rates during the worst drought known from 87 years of local records. At the height of the drought in 1965 the sown pastures supported animals as far into the drought as did the two native pasture treatments at half the stocking rate. Sorghum almum (CV. Crooble) and Rhodes grass (Chloris gayana CV. Pioneer) died late in the drought and did not re-establish after rain, whereas buffel grass (Cenchrus ciliaris CV. Nunbank) and green panic (Panicm maximum var. trichoglume CV. Petrie) survived. Standing dry matter in the pastures was less than 1,000 lb dry matter an acre for much of the life of the experiment. At a stocking rate of one bullock to 2.3 acres S. almm gave the highest average gain per head in the first full year of grazing (462 lb per head), but this was only significantly better (P<0.05) than the gain from buffel grass, and not significantly better than the gains (at one bullock to 4.6 acres) on native pasture (415 lb per head) and native pasture plus oats (390 lb per head). Rainfall in the first year was 18 inches. In the remaining two years, with 13 and 8 inches of rain respectively, there were no significant differences between the sown pastures until the S. almum and Rhodes grass died. Native pasture plus oats (681 lb per head) and native pasture (424 Ib per head) gave the greatest gain per head in 1964, but not per acre because of the lower stocking rate.

Dry matter, protein, energy and fibre intake by dairy heifers grazing a Rhodes grass (Chloris gayana) pasture

1981 ◽  
Vol 6 (1) ◽  
pp. 15-26 ◽  
Author(s):  
A. Abate ◽  
H. Kayongo-Male ◽  
C.N. Karue
Keyword(s):  
Dry Matter ◽  
Rhodes Grass ◽  
Fibre Intake ◽  
Dairy Heifers ◽  
Protein Energy ◽  
Chloris Gayana
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