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The Study of Grasses, Legumes and other Forage Plants Germplasm Resources in Xishuangbanna of Yunnan Province, China
Get PDFXishuangbanna Dai Autonomous Prefecture (XDAPJ is situated in Southern Yunnan, with an area of 19,220 km , being equivalent to 1/500 of the total area of China. The number of species in flowering, moss and fern plants altogether was estimated appriximately at 5,000 equalling to 1/6 of that in PRC, about as many as 1/3 of that in Yunnan. So that XDAP is well known as the « Green Treasure Land » throughout the country. Xishuangbanna lies at 21° !0\u27-22°37\u27N & 99°55\u27-101°50\u27E, consisting of 3 counties, Jinghong, Menghai and Mengla. The general topography is featured by higher in west and lower eastwards. Most lateritic soils (pH 4-6) were developed from weathered schist, phyllite and granite. Situating at south of tropic of cancer and being influenced by the monsoons from both the Pacific and Indian Oceans, here the climate is of 2 modes, monsoon and rainforests. The ;;,, 10°C accumulated temperature was totalled to 7,500. The plant growth time usually extends to nearly 365 days a year free from any frost and the annual mean precipitation goes up to 1,000 mm or more
Herbage Production from Grassland Under Stressed Environments in India
Get PDFIn India, out of the total reporting area of 304.21 m ha, forest covers 67.32 m ha (22.13 per cent) while permanent pastures, miscellaneous tree crops and groves, cultivable wastelands and fallow lands altogether cover 53.78 m ha (17.68 per cent). These are the potential areas available for grazing in one or other form. Only 4 per cent of the area of the cultivated land is under fodder crops which is far less compared to large livestock population (more than 400 million). In last ten years, the increase in cattle population had been about 7 per cent, buffalo and sheep 20 per cent each and a phenomenal increase of more than 40 per cent in goat population. The requirement of forage by AD 2000 is estimated at 822 m t as against the availability of only 478 m t at present. This widening gap is expected to increase unless necessary means are developed to increase herbage production from large chunk of land facing different kinds of stress environment
Chemical and Nutritive Values of Three Ensiled Residues (Broad Beans, Peas and Soybean) in Comparison with Yellow Lupin Silage
Get PDFThe agro-industrial residues of legumes in Portugal has increased recently in animal feeding, but with little information about the nutritive values of these diets. The few values from literature (Economides and Hadjidemetriou, 1974; Boza and Guerreiro, 1981 ; Escandon et al., 1983) or in Tables of Food Composition are quite different. In south of Portugal, the yellow lupin is an expanding forage used in sheep diets as hay or silage. The purpose of this work, and others in progress, was to compare the feeding value of silages made from three important residues with the yellow lupin silage
Haymaking from Tropical Grasses
Get PDFHaymaking from pasture growth surplus is an alternative way to provide winter feeding to cattle. Some interest has recently been developed toward making hay from tropical grasses in their vegetative stage. The main hazard with this approach being the occurence of likely rains during field drying. This can be helped by shortening drying time through the use of appropriate harvester (Savoie et al., 1982) as well as selection fo species with higher drying rate (Morris, 1972; Person and Sorenson, 1970)
Seasonal Variation of Cattle Daily Gain, Plant Characteristics and Solar Energy Conversion Efficiency in Grazing Pastures of Dactylis glomerata and of Festuca arundinacea
Get PDFHerbage intake, digestibility and leafiness or bulk density are well known as the main factors affecting the performance of grazing animals. But even in case where these factors are not so different, daily gain still varies among seasons or individuals (Blaser et al., 1981). In order to solve these problems by modeling approach (Okubo & Jacquard, 1985), seasonal changes in plant production, daily gain of cattle live-weight and seasonal variations in solar energy conversion into cattle gain were measured, and the importance (Okubo et al., 1985) of gross efficiency of digestible energy to net energy was discussed
Rates of Destruction of Growing Points of Pasture Legumes by Grazing Cattle
Get PDFTwining tropical pasture legumes such as Siratro ( Macroptilium atropurpureum) are unable to persist under sustained heavy grazing, whereas prost��ate legumes such as white clover (Trifolium repens) persist well. The reasons for this are not fully understood. Survival of individual Siratro plants is reduced by heavy grazing (Jones and Bunch, 1988). The destruction of growing points of erect legumes during grazing may reduce growth and weaken the plants. The effects of grazing pressure on the demography of growing points and on turnover of plant tissue have been studied at this Laboratory since 1984. Some results are reviewed briefly here
Towards Developing a Model of Persistence and Production for White Clover
Get PDFThe development of a model which successfully simulates the response of white clover Trifolium repens L. to environmental variables affecting persistance would be of great value for defining critical limiting processes. In Australia, persistence is determined by the impact of climate, competition and grazing on the processes of generation, from seed or by stolons (Jones, 1980; Archer and Robinson, 1988). Here we outline a model of white clover persistence and production in eastern Australia. In Australia the four critical phases in the lifecycle of white clover where the environment can threaten persistence are : late autumn and winter when germination may occur and seedlings may or may not survive ; spring when seedlings, if any, are recruited as adult plants ; early summer when flowering leads to replenishment of the seed pool ; and late summer and autumn when survival of stolon segments determines perennation. In cool temperate environments survival in this last phase is usually not threatened, and therefore the initial three phases are less important (Harper, 1978). However, in southeast Queensland and south-east USA, the last phase is often lethal, and therefore the first three phases constitute the normal Iifecycle (Jones, 1980; Blaser and Killinger, 1950)
Interactions Between Parent Stolons and Branches in Assimilate Partitioning in White Clover (Trifolium repens L.)
Get PDFIn temperate regions of the world, white clover (Trifolium repens L.) persists in permanent pastures by vegetative reproduction (Chapman 1987). Thus stolon branching is vital for the perennation of the species. There is, however, no information available on physiological relationships between branches and parent stolons, or on the degree of physiological integration of whole clover plants. Clover spreads laterally by stolon extension and in extremely heterogenous environments, like grazed pastures, parts of a single plant may encounter different levels of stress (defoliation, nutrient levels, shading). Physiological integration (eg. mutual exchange of carbohydrate between branches and parent stolon) may allow buffering of stresses within the whole plant, and thus determine to an extent the population biology and stability of the species. The experiments reported here were conducted to quantify physiological interactions between parent stolons and branches, and examine the possible consequence for growth of other organs of greater carbon partitioning to branches in highly-branched plants
The Influence of Physical and Biochemical Characteristics upon the Selection of White Clover by Grazing Sheep
Get PDFObservations have been made on the reactions of sheep to variations in leaf mark (Cahn and Harper, 1976) and cyanogenic glucoside concentration (Corkill, 1952) in white clover (Trifolium repens L.), but little is known about the relative importance of alternative visual and biochemical cues in selective behaviour under grazing conditions. This paper reports the results of two studies at DSIR Grasslands Division, Palmerston North, New Zealand on the reactions of grazing sheep to white clover plants exhibiting substantial genotypic variation in leaf size and colour, leaf mark, and cyanogenic glucoside potency
A Modified Linear Programming Method for Assesing the Effects of Mixed Grazing in the Heterogenous Environments
Get PDFThe aim of the programme of which this work is part is to investigate the role of mixed grazing in preservation of range vegetation and sustaining or improving animal production in the Senegalese Sahel. In this paper we apply the linear programming method of Connolly (1974) modified to allow for missing information, to data on animal preferences for plant species