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Articles 11011 - 11040 of 291657

Full-Text Articles in Physical Sciences and Mathematics

Using A Roller To Apply Herbicides For Control Of Brush Regrowth In Saskatchewan Pastures, John Waddington, Shabtai Bittman Jul 2025

Using A Roller To Apply Herbicides For Control Of Brush Regrowth In Saskatchewan Pastures, John Waddington, Shabtai Bittman

IGC Proceedings (1977-2023)

A carpet-covered roller was used to apply herbicides to control woody plant regrowth in established pastures in Saskatchewan, Canada. A 1.5% v/v solution of a 4:1 mixture of 2,4-D ((2,4-dichlorophenoxy) acetic acid]:picloram (4-amino-3,5,6-trichloropicolinic acid) controlled the above ground growth of several tree and shrub species fairly well, but regrowth from the roots or stem bases usually occurred the year after the year of treatment. Applying a 1.5% v/v solution of glyphosate [N-(phosphonomethyl) glycine] resulted in more individual plant death but less permanent damage to survivors than the treatment with 2,4-D: picloram. The machine worked fairly well but is probably best …

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Effect Of Bent Grass (Agrostis Tenuis) On The Growth And Wool Production Of Sheep In South East Australia, M E. Boyd Jul 2025

Effect Of Bent Grass (Agrostis Tenuis) On The Growth And Wool Production Of Sheep In South East Australia, M E. Boyd

IGC Proceedings (1977-2023)

An experiment determined the effect of infestation by bent grass on the productivity of pastures grazed by sheep in Victoria. The 5-year study of liveweights and wool production from sheep grazing bent grass and treated pasture demonstrated that the presence of bent grass can reduce the productivity from sheep grazing such pastures by up to 63%. Thorough, shallow cultivation (5-7 cm deep) during summer, followed by resowing of more desirable species, produced the greatest increase in animal production. The average wool production/head of wethers grazed at 8.6/hectare on pasture dominated by bent grass was the same as that of sheep …

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Fluctuation In Cattle Tick Population Density In Sown And Indigenous Pastures In Japan, I Ito, H Otake, K Sugawara Jul 2025

Fluctuation In Cattle Tick Population Density In Sown And Indigenous Pastures In Japan, I Ito, H Otake, K Sugawara

IGC Proceedings (1977-2023)

In order to understand the fluctuation in cattle tick ( Haemaphysalis longicomis) population density in Japanese grazing lands, we investigated tick density in sown and indigenous pasture in North East Japan from 1979 to 1984. It became clear that the life span of grazing cattle is longer in sown than in indigenous pasture. Nevertheless, cattle tick density is lower in sown pasture than in indigenous pasture. It appears that the grazing cattle have not only the role of host but also contribute to cattle tick mortality. We proved experimentally that a great number of ticks are eaten by the …

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Survival And Fecundity Of Spittlebugs On Different Grasses, S S. Nilakhe, G O. Paschoal, Y Savidan Jul 2025

Survival And Fecundity Of Spittlebugs On Different Grasses, S S. Nilakhe, G O. Paschoal, Y Savidan

IGC Proceedings (1977-2023)

Survival and development of nymphs, and survival and fecundity of spittlebug adults [Zulia entreriana (Berg.)] reared on different grasses were studied by caging the insects on potted grass plants in screenhouse. Overall, fewer nymphs reached adulthood when reared on Andropogon gayanus cv. CIAT621, Brachiaria decumbens cv. IRI700, Brachiaria brizantha cv. Marandu, Brachiaria mutica, Chloris gayana, Panicum maximum cv. Coloniiio, Paspalum guenoarum and Paspalum plicatulum than on Brachiaria decumbens cv. Basilisk, Brachiaria humidicola, Cenchrus ciliaris and P. maximum cv. K187B. Of the 240 nymphs used for P. guenoarum and P. plicatulum, none reached adulthood. Spittlebug adults reared on A. …

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Endophyte Fungus Increases Persistence Through Improved Pest Control, R A. Prestidge, G M. Barker, R P. Pottinger, K W. Steele Jul 2025

Endophyte Fungus Increases Persistence Through Improved Pest Control, R A. Prestidge, G M. Barker, R P. Pottinger, K W. Steele

IGC Proceedings (1977-2023)

Our objectives were to determine (1) the feeding and oviposition behaviour of Argentine stem weevil Listronotus bonariensis Kuschel feeding on ryegrass infected with Acremonium endophyte, and (2) to survey pastures to relate ryegrass content, Argentine stem weevil populations and larval damage to the incidence of Acremonium endophyte in pastures of known age. In preference tests, adult stem weevil fed more extensively and deposited more eggs on endophyte-free ryegrasses. Ryegrass content in surveyed pastures in the central North Island of New Zealand averaged only 35% of the sward after 2-3 years. The majority of rye grass plants were infected with Acremonium …

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Preliminary Experiments For Biological Control Of Snow Mold Caused By Typhula Incarnata And T. Ishikariensis, N Matsumoto, A Tajimi Jul 2025

Preliminary Experiments For Biological Control Of Snow Mold Caused By Typhula Incarnata And T. Ishikariensis, N Matsumoto, A Tajimi

IGC Proceedings (1977-2023)

Preliminary experiments for biological control of snow mold were made because the disease is the most serious problem in growing forage crops in snowy areas. Several low temperature saprophytes were collected to examine their antagonistic ability against snow mold pathogens. They were antagonistic in culture but generally failed to suppress the disease. However, there was a promising saprophyte. A prospect of biological control is discussed.

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Antifungal Activity Of Systemic Fungicides On Mycelial Growth Of Epichloe Typhina And Their Therapeutic Effects On The Choke Disease Of Timothy, T Shimanuki, T Sato Jul 2025

Antifungal Activity Of Systemic Fungicides On Mycelial Growth Of Epichloe Typhina And Their Therapeutic Effects On The Choke Disease Of Timothy, T Shimanuki, T Sato

IGC Proceedings (1977-2023)

The choke,a systemic disease, is a serious obstacle in the breeding and seed production of timothy in Japan, since the disease often prevents plant from normal heading. In this study, our goal was to cure the infected plants by systemic fungicide treatment. Among 15 chemicals tested, Bitertanol (Baycor) was most effective against the causal fungus, Epichloe typhina, in vitro tests, being completely fungicidal at 10 ppm. Triforine (Saprol) was effective being partially fungicidal at 10 ppm and completely fungicidal at 100 ppm. Benomyl, captafol+captan, chlorothalonil and triadimenol were fungistatic at 100 ppm and fungicidal at 1,000 ppm. In greenhouse test, …

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Laboratory Production Of The Sexual Stage Of Sclerotinia Trifoliorum, The Winter Crown-Rot Agent Of Red Clover Consequences For Improving Control Methods, G Raynal, J Picard Jul 2025

Laboratory Production Of The Sexual Stage Of Sclerotinia Trifoliorum, The Winter Crown-Rot Agent Of Red Clover Consequences For Improving Control Methods, G Raynal, J Picard

IGC Proceedings (1977-2023)

The production of large quantities of ascospores of Sclerotinia trifoliorum is possible in the laboratory. The sclerotia of the fungus are obtained on autoclaved potato slices after 1 month growth at 20°C, in the darkness. After that time, sclerotia are placed during 1 month at 30°C in order to remove their dormancy, then slightly hurried in humid vermiculite at 15°C, under fluorescent light. The first apothecia appear 1 month later, the production lasts for 2 months. The average yield is 2 x 103 to 4 x 103 apothecia for 104 sclerotia. Every apothecium produces an average of 3 x 104 …

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The Ecology And Control Of Barley Yellow Dwarf Viruses In Pasture Grasses, P L. Guy, G R. Johnstone Jul 2025

The Ecology And Control Of Barley Yellow Dwarf Viruses In Pasture Grasses, P L. Guy, G R. Johnstone

IGC Proceedings (1977-2023)

Barley yellow dwarf (BYD) infection is common in pasture grasses in temperate regions of the world. It directly reduces the growth of pasture grasses and may predispose them to attack by fungal pathogens. Measures which successfully control BYD in cereals may, with certain reservations, be useful to control the disease in pasture grasses. These include breeding cultivars which are either resistant or tolerant and various strategies to control the aphid vectors.

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Preliminary Report On The Occurrence Of The Root And Stalk Rot Of Corn Caused By Pythium Gramincola Subrm. In Japan, T Sato, T Shimanuki, T Tsukiboshi Jul 2025

Preliminary Report On The Occurrence Of The Root And Stalk Rot Of Corn Caused By Pythium Gramincola Subrm. In Japan, T Sato, T Shimanuki, T Tsukiboshi

IGC Proceedings (1977-2023)

In the early 1980s, a new stalk rot of corn occurred in Kanto, Japan. The diseased plants drooped first, then wilted within a few days. The disease appeared mostly on plants at the dent stage in late summer and fall. The stalks of the affected plants looked apparently healthy, but softened in some intern odes just above the ground. Longitudinal section of this portion showed a soft rot of inner tissues; pith was first water-soaked and abundant in oogonia and inflated mycelia, then turned brown and disintegrated, leaving the vascular strands intact. Prior to the stalk rot, severe root rot …

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Establishment And Productivity Of Perennial Ryegrass Improved By Control Of Fungi Pathogenic To Seedlings, R E. Falloon Jul 2025

Establishment And Productivity Of Perennial Ryegrass Improved By Control Of Fungi Pathogenic To Seedlings, R E. Falloon

IGC Proceedings (1977-2023)

Results of investigations into effects of fungicide seed treatments on establishment, productivity and seedling disease of perennial ryegrass (Lolium perenne L.) are reviewed. Seedling establishment from seed treated with protectant fungicides was increased compared with that from untreated seed. Seed treatment improved plant and sward productivity during the first year after establishment. Species of Fusarium and Pythium were virulent pathogens of young seedlings. Use of fungicide seed treatments as part of general pasture establishment practice is strongly recommended.

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Recent Advances In The Understanding Of Anthracnose Of Stylosanthes In Tropical America, Jillian M. Lenne Jul 2025

Recent Advances In The Understanding Of Anthracnose Of Stylosanthes In Tropical America, Jillian M. Lenne

IGC Proceedings (1977-2023)

Recent advances in the understanding of anthracnose (Colletotrichum gloeosporioides), the most damaging disease of Stylosanthes spp., are described with reference to the tropical American lowlands. During the past seven years, anthracnose evaluations of promising Stylosanthes spp., at major screening and RIEPT sites throughout the tropical American lowlands have revealed that although anthracnose is present at all sites, its severity varies among species and across ecosystems. From 1978 to 1981, field screening of S. capitata in Colombia and Brazil, found 94.2% of accessions resistant to anthracnose in Colombia while 85.1 % were susceptible in Brazil. These findings together with …

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Anthracnose On Native Florida Stylosanthes, J B. Brolmann, R M. Sonoda Jul 2025

Anthracnose On Native Florida Stylosanthes, J B. Brolmann, R M. Sonoda

IGC Proceedings (1977-2023)

The current status of anthracnose caused by Colletotrichum gloeosporioides (Penz.) Sacc. on Stylosanthes spp. in Florida is discussed. The pathogen was probably imported since it was not found on native stands of Stylosanthes in Florida. The reaction of Florida Stylosanthes to C. gloeosporioides, now present in Florida, ranges from resistant to moderately affected. Some accessions of native Florida S. hamata (L.) Taub., unaffected by the disease, have potential for forage use.

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Research On The Grassland Ecosystem In Inner Mongolia Of China And The Strategy Of Utilization, Shu Jiang Jul 2025

Research On The Grassland Ecosystem In Inner Mongolia Of China And The Strategy Of Utilization, Shu Jiang

IGC Proceedings (1977-2023)

The strategy on grassland utilization based on regional vegetation investigation and longterm ecosystem research in the middle part of Innermongolia is described. Although there are some potential capacity for increasing livestock number by the estimation of the primary productivity measurement and some investigation data, but practically, the pasture in some places has been degraded even desertified caused by unreasonable utilization of overgrazing and agricultural cultivations. Therefore on the strategy, to transform the structure both of pastoral and rural area in lnnermongolia would be necessary, i.e. to introduce some means of plantation for artificial range establishing at some limited azonal places. …

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A Microbial And Biochemical Study Of Grassland Under The Different Fertilization Practices, S Higashida, A Nishimune Jul 2025

A Microbial And Biochemical Study Of Grassland Under The Different Fertilization Practices, S Higashida, A Nishimune

IGC Proceedings (1977-2023)

The understanding of nutrient transformation in soil must be based on a knowledge of soil microbial activities. In order to clarify the relationship between fertilization and microbial activity, some microbial and biochemical characteristics were studied in some soils collected from the grassland under different fertilization practices, which caused marked changes in the uppermost part of grassland soil. The experimental plot was located in the northern part of Hokkaido, and the characteristics examined included bacterial and fungal numbers obtained by the plate methods, hyphal length, and the decomposing activities of urea, fructose, glucose, starch and protein. Simple correlation analysis indicated that …

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The Changes Of Population Structure Of Timothy (Phleum Pratense L.) In An Establishing Sward, H Sawada, T Takahashi, Ch Tsuda Jul 2025

The Changes Of Population Structure Of Timothy (Phleum Pratense L.) In An Establishing Sward, H Sawada, T Takahashi, Ch Tsuda

IGC Proceedings (1977-2023)

To study the changes of population structure in.an establishing sward of timothy, we carried out the field experiment, and the demography and the spatial distribution of timothy plants for about a half year. Plants decreased at expotential rate and the cohort of seedlings emerging until July was dominant at the last recording date. The frequency distribution of individual tiller number shifted to more right-skewed as plants grew. Large plants were liable to survive to the succeeding recording dates, and there were positive correlated relationship in the individual tiller number between recording dates, especially high between October and November (r=0.93). Plant …

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Vegetative Reproduction From Node And Population Structure Of Timothy (Phleum Pratense L.) In A Pasture, H Sawada, S Hirano, Ch Tsuda Jul 2025

Vegetative Reproduction From Node And Population Structure Of Timothy (Phleum Pratense L.) In A Pasture, H Sawada, S Hirano, Ch Tsuda

IGC Proceedings (1977-2023)

We found out the vegetative reproduction from node in timothy. We examined the demography and the intra-population variation of this reproduction in a 17-year-old pasture, and the potential ability to reproduce under the wet and undisturbed greenhouse condition. Also, clone analysis using peroxidase isozyme was carried out to detect the distributional patterns of genets in the above pasture. A number of propagules were found, most had short life-span but a few grew to flower and recruited into the large size class. Most propagules derived from the top-vegetative elongated tillers (Abnormal tillers), which appeared in autumn. This reproduction occured frequently in …

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The Effect Of Grass Tiller Density On The Performance Of White Clover, A J. Brereton, O T. Carton, A Conway Jul 2025

The Effect Of Grass Tiller Density On The Performance Of White Clover, A J. Brereton, O T. Carton, A Conway

IGC Proceedings (1977-2023)

The research was undertaken to obtain data on the factors affecting the ecological stability of grass/white clover swards. The objective was to monitor the changes in the level of clover dominance within and between seasons under different managements. The changes were compared with concurrent changes in the density of grass tillers. The results showed that clover dominance was reduced as grass tiller density increased. Clover dominance was maintained over three years in swards cut at 28-day intervals during the growing season. Clover declined progressively in swards cut at 14-day intervals. This decline was also related to an increase in grass …

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Distribution Of C3 And C4 Type Grasses, And Climatic Patterns In Korea, S K. Lee, N K. Chang Jul 2025

Distribution Of C3 And C4 Type Grasses, And Climatic Patterns In Korea, S K. Lee, N K. Chang

IGC Proceedings (1977-2023)

Stepwise multiple regression analyses were used in the aims to correlate statistically the geographic patterns in the abundance of½, C4 and CAM type grasses with patterns in climatic variables. The dominant grasses having the C3 , C4 and CAM pathways of photosynthesis were computed for the importance values of all the grass floras in 258 widely spaced regions of South Korea. From long-term climatic records, seasonal and annual values for solar irradiance, water supply, heat availability and combinations of these variables were assigned to each of 258 regions. The results of the analyses suggest that high humidity such as river …

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Observations On The Revegetative Plant Successions Resulting From Digging Den Activity Of Rodents In Mountainous Grasslands Of North-Western China, Chen Qing Cheng Jul 2025

Observations On The Revegetative Plant Successions Resulting From Digging Den Activity Of Rodents In Mountainous Grasslands Of North-Western China, Chen Qing Cheng

IGC Proceedings (1977-2023)

In this paper, the revegetative plant successions on the rodent den mounds built up by Marmota himalayana, Myospalax fotarerii and Ochotona dahurica on various types of grassland have been studied and described. The objectives of this study are to arrange systematically the general processes and series of these successions and to seek means for promoting the revegetation of these mounds in order to raise the yield of forages in these grasslands. Characteristics of plant succession on the mounds have been summed up and methods and techniques for promoting the revegetation of these secondary bare areas have been suggested.

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Effects Of Defoliation On The Difference In Growth Between Large And Small Plants In Swards, Y Takasaki, H Oizumi, H Nojima Jul 2025

Effects Of Defoliation On The Difference In Growth Between Large And Small Plants In Swards, Y Takasaki, H Oizumi, H Nojima

IGC Proceedings (1977-2023)

Stands of alfalfa (Medicago sativa) become sparser as cutting frequency is increased (Takasaki, 1980), while stands of orchardgrass (Dactylis glomerata) or tall fescue (Festuca arundinacea) become denser as cutting frequency is increased (Jung et al., 1974; Ishida et al., 1971). It is assumed that defoliation of swards increases the difference in growth between individual plants and causes some of them to die in the case of alfalfa, whereas in those of orchardgrass or tall fescue defoliation decreases the difference in growth and relieves stand reduction. In order to prove this assumption two experiments were …

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Herbage And Animal Production Of A Short Grass Pasture In A Mountainous Region Of Japan, M Fukuyama, M Shimamura, M Ushiyama, T Imura Jul 2025

Herbage And Animal Production Of A Short Grass Pasture In A Mountainous Region Of Japan, M Fukuyama, M Shimamura, M Ushiyama, T Imura

IGC Proceedings (1977-2023)

Herbage and animal production of a short grass pasture established by unplowed sowing were investigated for seven years under continuous grazing. Herbage production and consumption on the pasture were estimated by using cages. Moreover, light intensity was measured with the new portable solarimeter devised by the authors for pastures. Standing crop was kept at 200-300 g dry matter (DM)/m2 throughout the grazing season, 32-78% of which was below 3 cm from the ground surface. From these results, it was found that the standing crop scarecely fluctuate seasonally and considerable herbage mass existed under the lower layer near the ground. Furthermore, …

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The Mountain Grassland Category And Its Ecological Succession Of The Greater Xing'an Mountains, Wei Shaocheng, Zhu Tingcheng Jul 2025

The Mountain Grassland Category And Its Ecological Succession Of The Greater Xing'an Mountains, Wei Shaocheng, Zhu Tingcheng

IGC Proceedings (1977-2023)

The mountain grassland of the Greater Xing'an Mountains are divided into two sorts, nine groups, fifteen types. It is suggested that mountain grasslands are sub-climax for its character of the climate and artificial succession. This classification and the rules of community dynamics will help us to know the grasslands of this area systematically. It will provide a scientific basis for the rational exploiting and utilizing the resources of the forest and grasslands, and determining the way of the agricultural production on it.

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Seasonal Dry Matter Production In Grazed Pasture Of Agrostis Alba And Its Principal Component Analysis, T Okajima, T Okubo, R Kayama, M Kikuchi Jul 2025

Seasonal Dry Matter Production In Grazed Pasture Of Agrostis Alba And Its Principal Component Analysis, T Okajima, T Okubo, R Kayama, M Kikuchi

IGC Proceedings (1977-2023)

There are not so many reports about the matter production in the grazed pastures of short grass type. The purposes of this study are to clarify (1) the seasonal change of dry matter production and (2) the factors that affect those in the grazed redtop (Agrostis alba) pasture as short grass type. The grazing experiment was carried out in 1979, 1980 and 1981. Biomass of grasses (part of leaf, stem, standing dead and underground) was measured at the end of each grazing period in the rotation from May to October, and also in March, April and November. Principal component analysis …

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Energy Efficiency Of Primary And Secondary Production In Grazed Pasture Of Dactylis Glomerata As Compared With Those Of Paspalum Notatum, T Okubo, M Hirakawa, T Okajima, R Kayama, H Tano, N Kihira Jul 2025

Energy Efficiency Of Primary And Secondary Production In Grazed Pasture Of Dactylis Glomerata As Compared With Those Of Paspalum Notatum, T Okubo, M Hirakawa, T Okajima, R Kayama, H Tano, N Kihira

IGC Proceedings (1977-2023)

To evaluate and compare the key factors for energy efficiency in pasture production between temperate and subtropical grass sward, dry matter production and cattle gain were determined under grazing condition during 1979-1983. Seasonal changes in the biomass of above and underground organs and in surface litter were measured in the two types of the swards of orchardgrass mixed with Italian ryegrass and of Bahiagrass mixed with Vicia sp. In an e_xample of the conversion efficiency measured for the productive growing season in 1980 (Fig.1), Bahiagrass pasture fixed 1.36:% of global solar radiation as the net production including the growth of …

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The Stability Analysis And Energy Flow Through Leymus Chinensis Population, Zu Yuangang, Zhu Tingcheng Jul 2025

The Stability Analysis And Energy Flow Through Leymus Chinensis Population, Zu Yuangang, Zhu Tingcheng

IGC Proceedings (1977-2023)

This study examines the natural Leymus chinensis grassland in Northeast China. It is concerned with solar radiation and the photosynthesis, respiration and traspiration of the Leymus chinensis population. In the process of the energy flow through the Leymus chinensis population, the energy input is 5199 Kcal/m2·d; the energy consumption is 5132.31 Kcal/m2 ·d and the energy accumulation is 66.69 Kcal/ m2 ·d. Thus it can be seen that most of the energy is lost in the environment. As a result of the stability analysis, the equilibrium state is asymptotic stability in the process of the energy flow through the Leymus …

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Energy Distribution Of Alpine Grassland -Sheep System, Zhu Xingyun, Wang Qing Jul 2025

Energy Distribution Of Alpine Grassland -Sheep System, Zhu Xingyun, Wang Qing

IGC Proceedings (1977-2023)

The studies on sheep's grazing behaviour have been carried on in China in 50.s of this century. But the researches on the energy consumption for grazing sheep in the various of their states are very few. This paper mainly studies and discusses the energy consumption distribution for grazing sheep in their grazing behaviour.

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The Energy Intake And Its Dynamic In Alpine Grassland - Sheep Systems, Wang Qin Jul 2025

The Energy Intake And Its Dynamic In Alpine Grassland - Sheep Systems, Wang Qin

IGC Proceedings (1977-2023)

The experiment was carried out on alpine grassland, from 1978 to 1979, in Tianzhu Tibetan Autonomous County, Gansu Province. Local Tibetan sheep were used as the experiment animals.

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A Model For Plant And Cattle Growth In Ecological System Of Grazed Pasture, T Okubo, P Jacquard Jul 2025

A Model For Plant And Cattle Growth In Ecological System Of Grazed Pasture, T Okubo, P Jacquard

IGC Proceedings (1977-2023)

The purpose of this modelling work are to describe the seasonal biomass dynamics of pasture plants and also to describe the growth of plant and cattle in field condition under grazing. Emphasis was put on the fundamental conception that energy flow or growth of organisms should be expressed as a result of balance in substrates between the demand by growing organisms and the supply of source for it, not as a simple flow from source to sink. A similar type of flow diagram was tried to apply for the expression of growth or energy flow in the subsystems of three …

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Modelling Of A Stand Of Red Clover (Trifolium Pratense L.), P Jacquard, B Fleury, J P. Maitre Jul 2025

Modelling Of A Stand Of Red Clover (Trifolium Pratense L.), P Jacquard, B Fleury, J P. Maitre

IGC Proceedings (1977-2023)

A model of growth and development for the Cocksfoot has been adapted to Red Clover to used in a more complex model for mixed crop (legume and grass).

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