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通过育种方法可以提高RS杂种的产量。以使它们具有较强的与中间冰草和冰草竞争的能力,然而同样的育种努力也会用来提高中间冰草及冰草体外干物质的消化率与产量。Lamb等人(1984)以及Vogel等人(1986)已经证明冰草和中间冰草混合样本中,体外的干物质消化率和产量具有基本的遗传变异性。由于在RS群体中通常缺少体外干物质消化率的遗传变异,所以对这一纯种进行的育种工作或许会取得较大的成功。White和Wight(1981)提出冰草属牧草中最重要的饲草特征是产量和于物质的消化率。我们同意这样的观点,即体外干物质消化率在饲草品质单因素测定中要比其它组分馏分诸如细胞壁、半纤维素、纤维素及木质素好,这是因为正如我们指出的那样,这些馏分的消化率会发生差异。因为非细胞壁饲草成分实际上是100%可消化的,因而体外干物质消化率实际上反映了细胞壁消化率。本研究测定细胞壁组成所采用的方法,在禾草种中可有效地用于测定细胞壁干物质消化率遗传变异性的来源。根据小区的研究结果,作为饲草,RS和RD属间群体在中部大平原上目前以及今后的价值似乎有限。虽然还没有评价其它一些优良性状诸如在放牧压力下的存留能力,然而作为调查冰草纤维组成和消化率水平遗传控制的工具,杂种间属也许是有潜力的,这是因为在冰草的染色体组之间纤维组成和消化率虽然存在着较大的差异。
Breeding methods can increase the yield of RS hybrids. So that they have a stronger ability to compete with the middle grass and ice grass. However, the same breeding efforts will also be used to increase the dry matter digestibility and yield of the middle grass and ice grass. Lamb et al. (1984) and Vogel et al. (1986) have shown that there is a basic genetic variability in in vitro dry matter digestibility and yield in mixed samples of icy grass and mid-ice grass. Breeding of this purebred may have been more successful due to the general lack of in vitro genetic variation of dry matter digestibility in the RS population. White and Wight (1981) suggested that the most important characteristics of forage grass are the yield and the digestibility of the material. We agree with the observation that in vitro dry matter digestibility is better in single factor assays for forage quality than other component fractions such as cell walls, hemicelluloses, cellulose and lignin because, as we have pointed out, these The digestibility of fractions will vary. Because the non-cell wall forage composition is actually 100% digestible, in vitro dry matter digestibility actually reflects cell wall digestibility. The method used to determine cell wall composition in this study can be used to determine the source of genetic variability of cell wall dry matter digestibility in grass species. According to the results of the community study, as a forage grass, the value of the RS and RD genera in the Central Plains at present and in the future seems to be limited. Although some other elite traits have not been evaluated for their ability to survive under grazing pressure, intergeneric may have potential as a tool to investigate the genetic control of vernal fiber composition and digestibility levels, Although there is a big difference in fiber composition and digestibility between groups.