Winter growth stimulation by gibberellin in differentially grazed pastures of Phalaris tuberosa

1964 ◽  
Vol 4 (14) ◽  
pp. 225 ◽  
Author(s):  
CN Williams ◽  
GW Arnold
Keyword(s):  
Gibberellic Acid ◽  
Growth Stimulation ◽  
Soluble Carbohydrate ◽  
Initial Increase ◽  
Subsequent Increase ◽  
Grazed Pastures ◽  
Grazed Pasture

The effect of gibberellic acid sprays on' the winter growth of two pastures of Phalaris tuberosa L. differentially grazed for a period of four years prior to the investigation, was studied. The previously lightly grazed pasture had initially approximately ten times as much soluble carbohydrate in the underground parts as the heavily grazed pasture. Both pastures responded in the same way with an initial increase in yield with gibberelin but no subsequent increase. However, regrowth from cut areas treated with gibberellin was significantly greater on the lightly grazed pasture. Since the stubble remaining after cutting was very low in chlorophyll, it is suggested that the differential regrowth might be due to the higher levels of stored carbohydrate in the lightly grazed pasture.

Matching grass supply to grazing patterns for dairy cows under strip-grazing management

1998 ◽  
Vol 1998 ◽  
pp. 49-49
Author(s):  
R.J. Orr ◽  
S.M. Rutter ◽  
P.D. Penning ◽  
N.H. Yarrow ◽  
L.D. Atkinson ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Water Soluble ◽  
Grazing Management ◽  
Soluble Carbohydrate ◽  
Production Potential ◽  
Grazed Pasture ◽  
Holstein Friesian ◽  
Water Soluble Carbohydrate ◽  
Strip Grazing ◽  
Friesian Cows

Grazed herbage is the cheapest feed available for dairy cows but total intake of nutrients from grazed pasture alone is generally insufficient to allow high yielding dairy cows to reach their production potential. Cows have their main daily meal following afternoon milking in the period up to sunset (e.g. Rook et al., 1994 ). In addition, both the DM content and water soluble carbohydrate (WSC) concentration of grass increase over the day (e.g. Orr et al., 1997) due to the loss of moisture and the accumulation of the products of photosynthesis. Based on this evidence, this study tested the hypothesis that dairy cows receiving strip-grazing allocations following the afternoon rather than the morning milking would show higher intake rates and consequently higher milk yields.Twenty Holstein-Friesian cows (median calving date 10 February 1997) were each supplemented with 4 kg concentrates day-1 and strip-grazed a perennial ryegrass pasture in four groups of 5 cows.

Matching grass supply to grazing patterns for dairy cows under strip-grazing management

1998 ◽  
Vol 1998 ◽  
pp. 49-49 ◽  
Author(s):  
R.J. Orr ◽  
S.M. Rutter ◽  
P.D. Penning ◽  
N.H. Yarrow ◽  
L.D. Atkinson ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Water Soluble ◽  
Grazing Management ◽  
Soluble Carbohydrate ◽  
Production Potential ◽  
Grazed Pasture ◽  
Holstein Friesian ◽  
Water Soluble Carbohydrate ◽  
Strip Grazing ◽  
Friesian Cows

Grazed herbage is the cheapest feed available for dairy cows but total intake of nutrients from grazed pasture alone is generally insufficient to allow high yielding dairy cows to reach their production potential. Cows have their main daily meal following afternoon milking in the period up to sunset (e.g. Rook et al., 1994 ). In addition, both the DM content and water soluble carbohydrate (WSC) concentration of grass increase over the day (e.g. Orr et al., 1997) due to the loss of moisture and the accumulation of the products of photosynthesis. Based on this evidence, this study tested the hypothesis that dairy cows receiving strip-grazing allocations following the afternoon rather than the morning milking would show higher intake rates and consequently higher milk yields.Twenty Holstein-Friesian cows (median calving date 10 February 1997) were each supplemented with 4 kg concentrates day-1 and strip-grazed a perennial ryegrass pasture in four groups of 5 cows.

Comparison of crop yields and soil conditions during 30 years under annual tillage or grazed pasture

1990 ◽  
Vol 115 (1) ◽  
pp. 29-40 ◽  
Author(s):  
K. C. Tyson ◽  
D. H. Roberts ◽  
C. R. Clement ◽  
E. A. Garwood
Keyword(s):  
Crop Yields ◽  
Soil Conditions ◽  
Subsequent Increase ◽  
Soil C ◽  
Grazed Pasture ◽  
Earthworm Population ◽  
Soil C And N ◽  
C And N ◽  
Harvest Year ◽  
Major Factors

SUMMARYCrop yields and soil properties of grazed grass–clover pasture and arable plots at the Grasslands Research Institute, Hurley, UK. were measured over 30 years (1955–84). Yields of herbage declined from 9·6 t DM/ha in the first harvest year to 4–6 t in years 5 to 8 but subseque8tly increased (after liming) to give a mean yield of 8·2 t for 1963–84. Yields of barley in plots receiving a seed-bed application of 45 kg N/ha averaged (1962–80) 3·1 t/ha and, in plots top dressed with an additional 100 kg N/ha, 4·1 t/ha but after 1969, response to additional N and yield under both N treatments showed a marked decline.Soil carbon increased during the first 10 years under pasture from 1·2 to 1·8% and soil N from 0·13 to 0·17%. These increases, equivalent to 1 t C and 75 kg N/ha per year, occurred at the same time as the initial decline in herbage yield noted above. During the subsequent 20 years, C and N remained relatively constant and herbage yields increased. Soil C and N decreased under 30 years' arable management to 0·8% C and 0·1% N, equivalent to a loss of 290 kg C and 25 kg N/ha per year.Major factors that appear to have influenced herbage yields were (i) soil moisture, (ii) accumulation of N in the soil organic matter during the first 8 years and the subsequent increase in the rate of mineralization, and (iii) the action of the earthworm population in creating a stone-free, fertile layer of top soil. As for barley, it was concluded that yields could not be maintained indefinitely on this soil series, as a result of the loss of soil structure and the development of a compact layer of soil at plough depth.

scholarly journals LOW DOSES OF FENOXAPROP-P-ETHYL CAUSE HORMESIS IN LITTLESEED CANARYGRASS AND WILD OAT

2016 ◽  
Vol 34 (3) ◽  
pp. 527-533 ◽  
Author(s):  
T. ABBAS ◽  
M.A. NADEEM ◽  
A. TANVEER ◽  
A. ZOHAIB
Keyword(s):  
Seed Production ◽  
Growth Stimulation ◽  
Research Area ◽  
Initial Increase ◽  
Low Doses ◽  
Wild Oat ◽  
Crop Species ◽  
Pot Experiments ◽  
Promotive Effect ◽  
Number Of Seeds

ABSTRACT Hormetic effects of herbicides at ultra-low doses have been proved against range of crop species, although available data of herbicides hormesis about the weeds growth is very limited. This study investigates the promotive effect of low doses of fenoxaprop-Pethyl on growth and seed production of littleseed canarygrass and wild oat. Pot experiments were conducted twice in Wire House at Agronomic Research Area, University of Agriculture, Faisalabad, during 2014-15. Seven different concentrations of fenoxaprop-P-ethyl [0, 1, 3, 6, 9, 12 and 15 g a.i. ha-1] were applied as post emergence herbicide at 3-4 leaves stage of the weeds. Results revealed that increase in growth occurred within first two weeks after spraying at fenoxaprop-P-ethyl doses 1, 3 and 6 g a.i. ha-1. More growth stimulation as compared to all other treatments was observed at fenoxaprop-P-ethyl dose 6 g a.i. ha-1. This initial increase in growth sustains with time up to the maturity of both weeds and positively influences seeds production ability. Up to 28% and 17% increase in number of seeds per plants were occurred in littleseed canarygrass and wild oat, respectively. Doses above 6 g a.i. ha-1 negatively affect the weeds growth and seed production ability.

Viability of axillary buds of white clover (Trifolium repens) in grazed pasture

1992 ◽  
Vol 119 (3) ◽  
pp. 345-354 ◽  
Author(s):  
P. C. D. Newton ◽  
M. J. M. Hay ◽  
V. J. Thomas ◽  
H. B. Dick
Keyword(s):  
New Zealand ◽  
White Clover ◽  
Trifolium Repens ◽  
Axillary Buds ◽  
Spring Period ◽  
Grazed Pastures ◽  
Grazed Pasture ◽  
Pattern Of Variation

SUMMARYStolon nodes of white clover were sampled monthly for 18 months from continuously grazed (set stocked) and rotationally grazed pastures in New Zealand. Both pastures were stocked at 22·5 ewes plus lambs/ha. Axillary buds were classified into viability categories using an incubation technique. On average, 54% of nodes had non-viable or dormant buds, 25% had axillary buds that were viable but non-active and 0·1% bore reproductive buds. Although 21% of buds emerged, only 8·5% of nodes bore live branches. Bud activity was strongly inhibited during the spring period of both years and this inhibition could not be removed by incubation.The greatest bud viability occurred at node 4 (from the apex) although 30–40% of the buds at this position were non-viable. This pattern of variation changed somewhat with season. Some viable buds were present at nodes more than 20 from the apex but these were of low vigour. Secondary stolons had different patterns of bud activity from those of primary stolons until they comprised more than 16 nodes.

Nutrient cycling in grazed pastures. III. Studies on labelling of the grazed pasture system by solid [35S]gypsum and aqueous Mg35S04

1970 ◽  
Vol 21 (3) ◽  
pp. 455 ◽  
Author(s):  
AR Till ◽  
PF May
Keyword(s):  
Steady State ◽  
Nutrient Cycling ◽  
Specific Radioactivity ◽  
Sulphur Content ◽  
Sheep Grazing ◽  
Plant Materials ◽  
Grazed Pastures ◽  
Grazed Pasture ◽  
Sulphur Cycle

35S was applied to eight paddocks either onto strips that comprised 1/30 of the area of the paddock or uniformly over the paddock. It was applied as solid [35S]gypsum or aqueous Mg35SO4 at sulphur levels of either 130 mg/ha or 7.8 kg/ha. The specific radioactivity of wool grown by sheep grazing the paddocks showed that strip and uniform labelling gave similar results, that there was no retention of the applied sulphur in forms that were not eventually available to plants, and that after about 260 days the effective specific radioactivity of the cycling sulphur had approached a steady state. There were significant differences between the specific radioactivities of sulphur in phalaris and clover. The differences in the sulphur application levels produced plant materials having slightly different sulphur contents but the major changes in sulphur content were due to the natural sulphur cycle.

The chemical composition of high-sugar and control ryegrasses in grazed pastures at different latitudes throughout New Zealand

2014 ◽  
Vol 76 ◽  
pp. 169-176 ◽  
Author(s):  
G.P. Cosgrove ◽  
N.R. Mapp ◽  
P.S. Taylor ◽  
B.M. Harvey ◽  
K.J. Knowler
Keyword(s):  
Perennial Ryegrass ◽  
Animal Studies ◽  
Chemical Constituents ◽  
Water Soluble ◽  
Soluble Carbohydrate ◽  
Nitrogen Emissions ◽  
High Sugar ◽  
Grazed Pasture ◽  
Plant Chemical ◽  
One Year

Abstract Extrapolating from single-site animal studies of the effects of water soluble carbohydrate (WSC) on methane and nitrogen emissions requires knowledge of geographical and temporal variation in plant chemical constituents. To provide this, samples of grazed pasture were collected from experiments at four different latitudes over one year. At each site, one high-sugar perennial ryegrass (HSG) and two control cultivars of perennial ryegrass, were sampled at each grazing during a 12-month period and analysed for concentrations of WSC, crude protein (CP) and fibre (NDF). Compared with the controls the HSG was higher in WSC (overall mean 299 vs 260 g WSC/kg DM; P

Ethylene, Water Relations and Tolerance to Waterlogging of Three Eucalyptus Species

1981 ◽  
Vol 8 (6) ◽  
pp. 497 ◽  
Author(s):  
TJ Blake ◽  
DM Reid
Keyword(s):  
Water Relations ◽  
Ethylene Production ◽  
Stomatal Closure ◽  
Initial Increase ◽  
Flood Tolerance ◽  
Eucalyptus Species ◽  
Aerenchyma Formation ◽  
Subsequent Increase ◽  
Exogenous Ethylene ◽  
Lower Stem

Effects of flooding of the roots on ethylene levels and water relations of flood-tolerant and flood-susceptible eucalypts were studied in an attempt to shed light on mechanisms of adaptation to waterlogging. The order of most flood tolerant to least tolerant were Eucalyptus camaldulensis Dehnh., E. globulus Labill., and E. obliqua L'Hérit. Tolerance of flooding in E. camaldulensis was associated with an initial increase in ethylene production by the roots, a subsequent increase in ethylene evolution by the lower stem, and basal stem thickening and aerenchyma formation in response to flooding. In addition, exogenous ethylene gas (500 �ll-1) increased stem thickening in E. camaldulensis seedlings compared with untreated controls. Although treatment of the flood-susceptible E. obliqua with ethylene gas resulted in stem hypertrophy, flooding did not induce either the stem thickening response nor did it stimulate ethylene production. Eucalyptus globulus was intermediate as regards flood tolerance and basal stem thickening; ethylene production by the roots increased but it did not show marked hypertrophy of the unflooded lower stem and was unresponsive to exogenous ethylene gas. Water stress was not associated with flooding damage in eucalypts. Early stomatal closure as shown by high leaf stomatal resistances occurred in both the flood-tolerant and the flood-susceptible species and leaf water potential did not decrease in any of the three species in response to flooding. The results suggest that the high degree of flood-tolerance in E. camaldulensis may be due to (1) increased ethylene production which results in (2) tissue hypertrophy and basal stem thickening. Such tissue hypertrophy would permit the plant to eliminate the build-up of the potentially toxic gas ethylene and could also enhance the transport of oxygen to the roots. The other species lacked one or other of these adaptive mechanisms and exhibited a lesser degree of flood tolerance.

Reproducibility of dwarf pea shoot growth stimulation by homeopathic potencies of gibberellic acid

2008 ◽  
Vol 16 (4) ◽  
pp. 183-191 ◽  
Author(s):  
Stephan Baumgartner ◽  
Devika Shah ◽  
Johann Schaller ◽  
Urs Kämpfer ◽  
André Thurneysen ◽  
...  
Keyword(s):  
Gibberellic Acid ◽  
Shoot Growth ◽  
Growth Stimulation

scholarly journals Effect of hexachlorobenzene on haem synthesis

1972 ◽  
Vol 129 (2) ◽  
pp. 381-387 ◽  
Author(s):  
C. Rajamanickam ◽  
J. Amrutavalli ◽  
M. R. S. Rao ◽  
G. Padmanaban
Keyword(s):  
Female Rats ◽  
Initial Increase ◽  
Synthetase Activity ◽  
Subsequent Increase ◽  
Sequence Of Events ◽  
Mixed Function Oxidase System ◽  
Rate Limiting ◽  
Cytochrome P 450

Several drugs are known to induce the liver microsomal mixed-function oxidase system when administered in vivo or even in vitro in cell culture. A sequence of events has been suggested in which the drug is visualized to induce δ-aminolaevulinate synthetase, the first and rate-limiting enzyme of the haem-biosynthetic pathway, which is followed by enhanced haem synthesis and cytochrome P-450 content, facilitating the increase in the drug-metabolizing activity of the liver microsomal fraction. The present studies show that the fungicide hexachlorobenzene, when administered to female rats, can lead to enhanced amounts and rate of synthesis of cytochrome P-450 under conditions when the rate of total haem synthesis has not appreciably altered. The subsequent increase in the rate of total haem synthesis as well as the initial increase in amounts of cytochrome P-450 are brought about under conditions when δ-aminolaevulinate synthetase activity remains constant. However, manifestation of porphyria due to prolonged drug administration is accompanied by a twofold increase in δ-aminolaevulinate synthetase activity. The increase in enzyme activity appears to be due to a decreased degradation rate of the enzyme.

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