Effect of defoliation frequency on growth and survival of four accessions of Psoralea eriantha

1975 ◽  
Vol 15 (75) ◽  
pp. 493 ◽  
Author(s):  
RC Gutteridge ◽  
PC Whiteman
Keyword(s):  
Dry Matter ◽  
Total Yield ◽  
The Other ◽  
Average Yield ◽  
Growth And Survival ◽  
Cutting Interval ◽  
Defoliation Frequency ◽  
The One ◽  
Cutting Regimes ◽  
Semi Arid

Four accessions of the semi-arid shrub legume Psoralea eriantha were evaluated under three six and nine week cutting regimes for 72 weeks in pots in the glasshouse. Total yield increased in all accessions with increasing intervals between cutting. Yield in the three week cutting interval was only 36 per cent of the yield in the nine week cutting interval. The one erect accession, though giving the highest average yield, also suffered the highest mortality under the frequent defoliation. The other accessions suffered little mortality. Defoliation frequency affected root and stubble weights and these were closely correlated with total dry matter yields. Frequent defoliation also markedly reduced the number of primary and secondary shoots. It is suggested that survival under grazing may be more important than a higher yielding ability.

Agronomic characteristics, silage quality, intake and digestibility of five new Brazilian sorghum cultivars

2014 ◽  
Vol 153 (2) ◽  
pp. 371-380 ◽  
Author(s):  
A. L. A. NEVES ◽  
R. D. SANTOS ◽  
L. G. R. PEREIRA ◽  
G. F. OLIVEIRA ◽  
C. B. SCHERER ◽  
...  
Keyword(s):  
Dry Matter ◽  
Nutritive Value ◽  
Block Design ◽  
The Other ◽  
High Yield ◽  
Agronomic Characteristics ◽  
North Eastern ◽  
Silage Quality ◽  
Semi Arid

SUMMARYForage sorghum (FS) (Sorghum bicolor(L.) Moench) is a key feed source for ruminants owing to its high yield and drought tolerance. The present paper assessed the agronomic characteristics, silage quality, intake and digestibility of five new Brazilian sorghum cultivars (BRS Ponta Negra variety, BRS 655 hybrid, BR 601 hybrid, BRS 506 variety and BRS 610 hybrid). Forages were grown (randomized complete block design) in a typical Brazilian north-eastern semi-arid climate, irrigated with 267 mm water, harvested as plants reached the soft dough stage of grain maturity and ensiled under laboratory and farm conditions. Apparent digestibility of the silages was determined using 25 Santa Inês lambs. BRS 506 outperformed the other cultivars in dry matter (DM) and digestible DM yields/ha. BRS 506 exhibited the lowest neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents and the highestin vitrodry matter digestibility (IVDMD) of the cultivars examined. BRS 655 produced the lowest level of lactic acid and the highest pH and ammonia-N concentration. There was no difference in intake or digestibility of DM among cultivars. Silages produced from BRS Ponta Negra resulted in higher crude protein (CP) intake than BRS 655. Silages made from BRS 506 and BRS Ponta Negra resulted in a greater digestibility of CP than those produced from BRS 655. Intake of NDF in silages generated from BRS Ponta Negra and BRS 610 was higher than that found in other cultivars. Although an average Brazilian North-eastern FS exhibited similar characteristics to other cultivars grown in dry regions around the world, the results indicated that BRS 506 had a yield advantage and higher nutritive value under Brazilian semi-arid conditions as compared to the other cultivars examined.

Defoliation frequency and the response by white clover to increasing phosphorus supply 1. Leaf dry matter yield and plant morphology responses

1997 ◽  
Vol 48 (1) ◽  
pp. 111 ◽  
Author(s):  
D. K. Singh ◽  
P. W. G. Sale
Keyword(s):  
Leaf Area ◽  
White Clover ◽  
Dry Matter ◽  
Leaf Size ◽  
Plant Morphology ◽  
Application Rate ◽  
Leaf Number ◽  
Growth And Survival ◽  
Defoliation Frequency ◽  
P Supply

A glasshouse experiment was carried out to determine how an increasing P supply influences the growth and survival of white clover plants subjected to a range of defoliation frequencies. Treatments involved the factorial combination of P application rate (0, 30, 90, and 180 mg/pot) to a P-deficient Krasnozem soil and defoliation frequency (1, 2, or 4 defoliations over 36 days). The survival of P-deficient plants was threatened by the most frequent defoliation; their leaf area declined owing to a reduction in leaf number and individual leaf size with each successive defoliation. Increasing the P supply to 180 mg/pot reversed this downward trend as the high P plants were able to maintain leaf area by increasing leaf size and number. Increasing the frequency from 1 to 4 defoliations over the 36 days also changed the form of the leaf dry matter response to added P, from an asymptotic to a linear response. The P requirement of white clover for maximum leaf yield therefore increased under frequent defoliation. This effect was also apparent for a range of morphological measurements including stolon elongation rate, leaf area, root mass, leaf number, and stolon number, where the magnitude of the P response was consistently greater for frequently defoliated plants. Exceptions included stolon mass, which responded more to P addition under infrequent defoliation.

Relationship Between Climate and Provenance Variation in Eucalyptus Camaldulensis Dehnh.

1995 ◽  
Vol 22 (3) ◽  
pp. 453 ◽  
Author(s):  
A Gibson ◽  
EP Bachelard ◽  
KT Hubick
Keyword(s):  
Dry Matter ◽  
Eucalyptus Camaldulensis ◽  
Humid Tropics ◽  
The Other ◽  
Northern Australia ◽  
Axillary Shoots ◽  
Dry Tropics ◽  
Temperature Ranges ◽  
Eucalyptus Camaldulensis Dehnh ◽  
Semi Arid

The morphology and physiology of Eucalyptus camaldulensis seedlings grown from seed collected from two locations in the dry tropics, two in the humid tropics and two in semi-arid Northern Australia were compared in phytotron growth cabinets under well-watered and water-limited conditions and diurnal temperature ranges of 30-25 and 22-15�C. Seedlings from the two locations in each climate resembled each other more closely than they resembled seedlings from the other climates across the range of conditions tested. When water-limited, seedlings from the dry tropical and semi-arid climates had a higher allocation of dry matter to roots than seedlings from the humid tropics. However, those from the dry tropics shed their lower leaves and initiated small-leaved axillary shoots while those from the semi-arid climate retained their leaves and did not produce axillary shoots. In contrast, seedlings from the humid tropics responded by reduced gas (CO2 and H2O) exchange without changes in morphology or allocation of dry matter. These responses are appropriate for growth in each climate and are consistent with observations made on wild trees in the field, on trees in plantations overseas and also with data from seedlings grown in earlier glasshouse experiments.

Yield and persistence of irrigated lucernes cut at different frequencies, at Tamworth, New South Wales.

1986 ◽  
Vol 26 (2) ◽  
pp. 165 ◽  
Author(s):  
GM Lodge
Keyword(s):  
Dry Matter ◽  
New South ◽  
Total Yield ◽  
Dry Matter Yield ◽  
South Wales ◽  
Cutting Frequency ◽  
Plant Persistence ◽  
Cutting Interval ◽  
The Mean ◽  
The Individual

Three irrigated lucerne cultivars, Pioneer Brand 545 (winter dormant), Condura 73 Brand (semiwinter dormant), and CUF 101 (highly winter active), were harvested at fixed cutting intervals of either 25, 28 ,35, 42 or 48 days from September to April in each of four years. This paper reports the effects of these cutting frequencies on the dry matter yield, leaf to stem ratio and persistence of these cultivars. The effect of cutting frequency on mean total yield (the sum of the mean yields for each harvest) was significant (P<0.05) in each year of the experiment, except year 3. Yields were highest in the 35-day cutting frequency in years 1 and 2. In the fourth year of the experiment the mean total yield of Pioneer Brand 545 and Condura 73 Brand was 29% higher (P<0.05) than CUF 101. By the fourth year substantial amounts of grass were present in the 25- and 28-day cutting interval plots. The contrasts between dormant and active cultivars for the dry matter yield of each of the individual harvests were not consistent in the first two years. In the third and fourth years the active initially outyielded the dormant cultivars at all cutting intervals, but yields of both were generally similar at the end of the season. Increasing the interval between successive harvests generally decreased the mean leaf to stem ratio. The ratio of leaf to stem for CUF 101 was significantly lower (P<0.05) than that for Pioneer Brand 545, with Condura 73 Brand tending to be intermediate. Within cutting intervals, mean declines in plant persistence were similar for cultivars from the different dormancy groups. Largest changes in plant frequency occurred in the fourth year when the mean frequency for the 25- and 28-day plots decreased from 69 to 12% compared with a mean decline from 74 to 65% for the 42- and 48-day cutting intervals. Productive stand life in this experiment was 3 years, even though disease was negligible. Under these conditions grass invasion was mainly related to harvest interval and much less to cultivar dormancy.

The Methodology of Historical Climate Reconstruction and its Application to Africa

1979 ◽  
Vol 20 (1) ◽  
pp. 31-49 ◽  
Author(s):  
Sharon E. Nicholson
Keyword(s):  
Arid Regions ◽  
Indirect Evidence ◽  
The Other ◽  
Short Term ◽  
The Past ◽  
Droughts And Floods ◽  
The Mean ◽  
The One ◽  
Semi Arid ◽  
Past Millennium

This article deals with climatic reconstruction over a period of centuries, on the basis of indirect evidence found in historical and geographical sources. Histories, archives, local chronicles and journals of travellers and settlers contain references to lakes, landscapes, famines, droughts and floods, as well as occasional descriptions of climate and meteorological measurements. Such information can be combined with evidence from geology, palynology or the study of tree-rings to support hypotheses regarding climate and environment several centuries ago.This methodology is here described and used to reconstruct the trend of rainfall fluctuation in Africa over the past millennium. Two approaches are considered: the one seeks to determine absolute variation (thus assessing whether particular episodes were wetter or drier than today); the other focuses on short-term climatic anomalies (e.g. droughts) in which rainfall differed from the mean prevailing at the time, without seeking to relate them to present conditions.The results obtained from this study suggest that during the past millennium there have been two periods of relatively wet conditions in the semi-arid regions south of the Sahara: between the eighth and fourteenth centuries, and between the sixteenth and eighteenth centuries. Evidence for these episodes, and for synchronous fluctuations elsewhere in Africa is presented in the text.

The effects of pelleting various diets on intake and digestibility in sheep and cattle

1973 ◽  
Vol 16 (3) ◽  
pp. 223-233 ◽  
Author(s):  
J. F. D. Greenhalgh ◽  
G. W. Reid
Keyword(s):  
Particle Size ◽  
Dry Matter ◽  
Diet Composition ◽  
The Other ◽  
Middle Aged ◽  
High Quality ◽  
Dry Matter Digestibility ◽  
Long Form ◽  
The One

SUMMARY1. Three groups of six castrated male cattle aged 6,18 and 36 months and three corresponding groups of sheep received in turn three diets consisting of high-quality dried grass (A), low-quality grass (B) or 60% of B with 40% barley (C). For one-half of each 6-week period the grass was eaten in the long form (L) and for the other half, it was ground and pelleted (P).2. Pelleting increased intake by 45% in sheep, from 56·8 to 82·4 g dry matter per kg W-75 per day, but only by 11% in cattle, from 81·8 to 90·7. The increase was greater for diet B (44%) than for A (19%) or C (15%), and greater for the youngest animals (38%) than for the middle-aged (17%) or oldest (20%).3. Dry-matter digestibility was reduced by pelleting from 67·2% to 58·6% in sheep and from 69·9% to 56·9% in cattle. The reduction was greater for diets A (71·2% to 56·1%) and B (65·7% to 54·1%) than for diet C (68·7% to 63·2%).4. A hypothesis based on the importance of particle size of digesta leaving the rumen provides a possible explanation ofthese interactions between form of roughage on the one hand, and species and age of animal or diet composition on the other.

Some water and dry-matter relationships in the food and droppings of laying hens

1958 ◽  
Vol 51 (2) ◽  
pp. 237-242 ◽  
Author(s):  
C. Tyler
Keyword(s):  
Water Intake ◽  
Dry Matter ◽  
Laying Hens ◽  
Time Of Day ◽  
The Other ◽  
Typical Pattern ◽  
Water Excretion ◽  
Water Output ◽  
The One ◽  
Metabolic Water

1. An experiment with one non-laying and four laying hens was carried out. Food and water consumption was measured hourly from 06.00 to 22.00 hr. and in the same period the exact time of each excretion was noted. Determinations of water and dry matter were made on each separate excretion.2. Each bird showed a typical pattern of behaviour in relation to the time of day when it ate food and drank water. For any one bird, variations of this pattern from day to day were small.3. For each bird there was a highly significant relationship between water intake and temperature on the one hand, and water excretion via droppings and eggs on the other. Water intake, however, had a far greater influence than had temperature on water output.4. Calculations showed that, despite errors caused by not knowing the amount of metabolic water produced, the excretion from the lungs varied greatly from bird to bird on constant intakes of water and also in the same bird at different intakes.

The geography of semi-arid lands

1977 ◽  
Vol 278 (962) ◽  
pp. 457-475 ◽  
Keyword(s):  
Arid Regions ◽  
Arid Zone ◽  
Arid Lands ◽  
The Other ◽  
Economic Opportunity ◽  
Poor Countries ◽  
The One ◽  
Migratory Movements ◽  
Semi Arid ◽  
Soil And Water

Semi-arid lands were at times during the last 20000 years more humid and at other times more arid than at present, with important consequences for the soil and water resources of the present day. These lands were the scene of the beginnings of pastoralism, the cultivation of cereals, and urban living between 10 000 and 5000 years ago. The environment has always been attractive to man but it is liable to deteriorate towards desert with long-lasting consequences. Development possibilities diversify according to environmental conditions which vary from place to place and also according to the economic and other characteristics of the States in which these lands are situated. The States can be regarded as falling into four categories: there are on the one hand wealthy countries - either industrialized or rich in minerals; on the other hand there are poor countries - some with land outside the arid zone as yet not fully developed, others with no land of this kind. In response to the differences in economic opportunity, migratory movements are taking place, notably from the impoverished semi-arid regions to the towns, particularly those in the petroleum-producing states.

Performance of fourteen Leucaena lines at five sites in Queensland

1988 ◽  
Vol 28 (1) ◽  
pp. 69 ◽  
Author(s):  
RA Bray ◽  
DG Cooksley ◽  
TJ Hall ◽  
D Ratcliff
Keyword(s):  
Dry Matter ◽  
Total Yield ◽  
F1 Hybrids ◽  
Growing Seasons ◽  
Cutting Interval

Ten lines of Leucaena leticoceyhala, 1 of L. diversifolia and 3 L. leucocephalax L. pulrerulenta F1 hybrids were grown at 5 contrasting sites in Queensland. Harvests were taken over 3 growing seasons, and dry matter yields estimated. The F1 hybrids were outstanding in most environments, outyielding cv. Cunningham by an average of 45%; the L. Ieucocephala lines CPI 58396 and 61227 and cv. K8 consistently outyielded cv. Cunningham by an average of 24%. When 2 contrasting cutting intervals were compared at Lansdown, there was no effect on dry matter yields, although the longer cutting interval produced more wood. The range of mimosine concentrations in the L. Ieucocephala lines was 4.1-5.6%. CPI 6 1227 had significantly lower mimosine content than cv. Cunningham. The genotype x site interaction for total yield was significant (P< 0.01). However, ranking of lines of L. leucocephala was fairly consistent across environments.

Establishment studies V. The effect of method of establishment on the behaviour of long-term leys in the seeding year

1963 ◽  
Vol 60 (1) ◽  
pp. 1-10 ◽  
Author(s):  
A. H. Charles
Keyword(s):  
Cover Crop ◽  
Crude Protein ◽  
Dry Matter ◽  
Total Yield ◽  
Red Clover ◽  
General Purpose ◽  
The Other ◽  
Grazing Management ◽  
Dry Matter Yield

1. In the seeding year the total dry-matter yield in swards sown without a cover crop was increased by infrequent defoliation, but the yield of crude protein was decreased. The highest production of starch equivalent was obtained when a cover crop was used.2. In the absence of a cover crop, the yield of red clover was higher under infrequent defoliation, but the yield of white clover was higher under frequent grazing.3. Frequent grazing, and the use of a cover crop, reduced the ingress of weeds more than infrequent defoliation. Nitrogen applied to the cover crop also reduced the growth of weeds.4. Nitro-chalk increased the total yield of herbage except when under a cover crop; it reduced the growth of red and white clovers, but this was not so marked under frequent grazing.5. Nitro-chalk increased the annual yield of crude protein under frequent grazing, but decreased it in all herbage mixtures under infrequent defoliation; nitrogen had no effect when a cover crop was used. The increase in yield of starch equivalent due to the application of nitrogen and its apparent recovery was greater under frequent grazing than under the other two managements. Under infrequent defoliation, in the absence of a cover crop, the recovery of nitrogen was particularly low.6. The ryegrass mixture and ryegrass-dominant general-purpose mixture made more growth, and suppressed clover and weeds to a greater extent than did the timothy and cocksfoot mixtures. This was modified by management in that ryegrass was particularly aggressive under frequent grazing (management 1) but not under managements 2 and 3.7. In the autumn of the seeding year the yield of total herbage was highest under infrequent defoliation, particularly in the cocksfoot, and general-purpose swards. All undersown mixtures gave lower yields than when no cover crop was used.8. Nitrogen increased the yield of herbage in May and June under frequent grazing, and in the August cut under infrequent defoliation, but in the autumn particularly it was reduced where a cover crop was used.9. The application of nitrogen decreased the protein content in all herbage mixtures when a cover crop was used or when defoliation was infrequent. Under frequent grazing the nitrogen increased the percentage of crude protein in the first two grazings, but decreased it in the September grazing.10. The production from the various mixtures was modified by management: under frequent grazing in May the ryegrass-dominant mixtures were higher yielding than the others, but in July the general-purpose and cocksfoot swards were the most productive. Under infrequent defoliation in August the timothy mixture had the highest yield and cocksfoot the lowest, and under this management cocksfoot and timothy swards had the highest yield in the autumn of the seeding year.

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