豆科牧草研究进展(英文)  

Advances in Forage Legume Technology

作　　者：JohnFrame 

机构地区：[1]ArdChoille,13StVincentCrescent

出　　处：《草业学报》2001年第4期1-17,共17页Acta Prataculturae Sinica

基　　金：国家重点基础研究发展规划项目"草地与农牧交错带生态系统重建机理及优化生态-生产范式"资助 (编号G2 0 0 0 0 186 0 2 )~~

摘　　要：豆科牧草的属间、属内、种间与种内均存在着巨大的遗传变异 ,利用这种变异 ,通过育种与选择 ,已培育出可良好地适应广泛的环境与管理条件的品种 ,遗传操作为此提供了更为广阔的空间。在豆科牧草固氮方面 ,对固氮过程、氮向伴生禾草的传送途径及残余氮对后继农作物的价值均有了进一步的理解。对包括施氮、采摘策略和影响混播草地中禾本科 豆科牧草平衡的胁迫等相互作用因素均已给予了阐明。在禾草 /白三叶草草地为基础的家畜生产系统中 ,氮素的损失及其对环境产生的不良作用低于大量施氮的禾草草地系统。与禾草相比 ,豆科牧草无论是用作放牧、青贮或用作干草 ,其物理、化学和解剖学等方面的特性均可增加家畜的嗜食性和自由采食量。由于豆科牧草的营养价值、可利用营养成分和采食特征 ,在单一豆科牧草或豆科牧草比重较大的禾草 豆科牧草混播草地上采食的不同种类、不同类型家畜的个体生产性能均优于在禾草草地上采食者。值得注意的是浓缩单宁在动物营养中的有益作用 ,这类单宁存在于诸如百脉根 (Lotuscorniculatus)、红豆草 (Onobrychisviciifolia)和冠状岩黄芪(Hedyscrumcoroharium)等植物中 ,其防止家畜患膨胀病 ,通过使较多的氨态氮到达小肠而提高氮素的利用 ,并减轻绵羊肠道中线虫的作用。显然 。Breeding and selection within the vast pool of genetic variability that exists among and within the species of different genera of forage legumes have led to cultivars that are well adapted to a wide range of environmental and management conditions; genetic manipulation techniques offer further scope. There is increased understanding of the N 2?fixation process, the routes of N transfer to associated grasses and the residual N value to subsequent arable crops. The interacting factors that include fertiliser N, defoliation strategies and stresses for example, and which govern the grass?legume balance in mixed associations, have been elucidated. Nitrogen losses with their adverse effects on the environment are lower in animal production systems based on grass/white clover than on highly N?fertilised grass swards. The physical, chemical and anatomical features of forage legumes, whether utilised as grazing, silage or hay, all contribute to enhanced acceptability and voluntary food intake compared with grasses. The net result of the legume nutritive value, nutrient availability and intake characteristics is superior individual animal performance from different types and classes of livestock fed on legume monocultures or legume?rich grass?legume mixtures relative to being fed on grass. A notable finding is the beneficial role in animal nutrition of condensed tannins, present in Lotus corniculatus, Onobrychis viciifolia and Hedysarum coronarium for instance; these tannins prevent bloat in livestock, improve N utilisation through more non?ammonia N reaching the small intestine, and alleviate the effects of intestinal nematodes in sheep. The development of transgenic legumes containing condensed tannins is clearly a major objective for plant breeders. A number of alternative uses for forage legumes has been identified that include protective vegetation in vineyards, a living understorey for cereals, and provision of secondary compounds for the pharmaceutical industry for example. With their plant diversity and palette o

关 键 词：豆科牧草 品种培育 固氮 浓缩单宁 饲用价值 选择性利用 

分 类 号：S54-3[农业科学—作物学]