Abstract:

【Objective】 Through correlation analysis between saponins content and agronomic characters in alfalfa, the authors try to find out one trait which can sign saponins content quickly and explore the rule about heritability and variation of saponins content.【Method】 A new cultivar of Hot-wet alfalfa named Yumu No.1 was used as materials in this research, one hundred alfalfa plants were determined, five high saponin plants and five low saponin plants were selected. 【Result】 Saponins heritability of these 10 alfalfa plants changed from 0.118 to 0.745 through experiments on the lines of offsprings of every plant, and variation coefficient of the lines of offsprings changed from 15.54% to 28.81%, the heritability of high and low saponin groups was 0.636 and 0.208, respectively, and the heritability of high saponin group was obviously higher than low saponin group. The result of correlation and path analysis between the saponins content and plant height, leaf color, pest extent, dry weight as well as the dry matter content showed that there was an extremely significant relationship (r=-0.405**) between leaf color and saponins content, and the saponins content was affected by leaf color directly (P=-0.422**) . The correlation between dry weight and saponins content was affected by plant height, leaf color and dry matter indirectly. 【Conclusion】 It is difficult to breed low saponin cultivar in alfalfa through general breeding method, but some lines of offsprings with high saponin content can be used as materials for breeding of high saponin content alfalfa cultivar. Leaf color of alfalfa can be used as a marker to identify saponins content in alfalfa quickly.

Key words: Medicago sativa L., saponins, heritability, agronomic characters, correlation analysis