Departamento de Biología Vegetal, Sección Biología Vegetal, Universidad de Navarra, c/Irunlarrea 1, 31008 Pamplona, Spain.
J Plant Physiol. 2012 May 15;169(8):782-8. doi: 10.1016/j.jplph.2012.01.010. Epub 2012 Feb 25.
Elevated CO(2) may decrease alfalfa forage quality and in vitro digestibility through a drop in crude protein and an enhancement of fibre content. The aim of the present study was to analyse the effect of elevated CO(2), elevated temperature and Sinorhizobium meliloti strains (102F78, 102F34 and 1032 GMI) on alfalfa yield, forage quality and in vitro dry matter digestibility. This objective is in line with the selection of S. meliloti strains in order to maintain high forage yield and quality under future climate conditions. Plants inoculated with the 102F34 strain showed more DM production than those inoculated with 1032GMI; however, these strains did not show significant differences with 102F78 plants. Neutral or acid detergent fibres were not enhanced in plants inoculated with the 102F34 strain under elevated CO(2) or temperature and hence, in vitro dry matter digestibility was unaffected. Crude protein content, an indicator of forage quality, was negatively related to shoot yield. Plants inoculated with 102F78 showed a similar shoot yield to those inoculated with 102F34, but had higher crude protein content at elevated CO(2) and temperature. Under these climate change conditions, 102F78 inoculated plants produced higher quality forage. However, the higher digestibility of plants inoculated with the 102F34 strain under any CO(2) or temperature conditions makes them more suitable for growing under climate change conditions. In general, elevated CO(2) in combination with high temperature (Climate Change scenario) reduced IVDMD and CP content and enhanced fibre content, which means that animal production will be negatively affected.
升高的 CO2 可能会通过降低粗蛋白和增加纤维含量来降低紫花苜蓿饲料质量和体外消化率。本研究的目的是分析升高的 CO2、升高的温度和根瘤菌菌株（102F78、102F34 和 1032GMI）对紫花苜蓿产量、饲料质量和体外干物质消化率的影响。这一目标符合选择根瘤菌菌株的要求，以维持未来气候条件下的高饲料产量和质量。接种 102F34 菌株的植物比接种 1032GMI 的植物产生更多的 DM，但这些菌株与 102F78 植物没有显著差异。在升高的 CO2 或温度下，接种 102F34 菌株的植物中中性或酸性洗涤剂纤维没有增加，因此体外干物质消化率不受影响。粗蛋白含量是饲料质量的一个指标，与地上生物量呈负相关。接种 102F78 的植物与接种 102F34 的植物具有相似的地上生物量，但在升高的 CO2 和温度下具有更高的粗蛋白含量。在这些气候变化条件下，接种 102F78 的植物生产出更高质量的饲料。然而，在任何 CO2 或温度条件下，接种 102F34 菌株的植物具有更高的消化率，这使它们更适合在气候变化条件下生长。一般来说，升高的 CO2 与高温（气候变化情景）结合降低了 IVDMD 和 CP 含量并增加了纤维含量，这意味着动物生产将受到负面影响。
