钙离子胁迫对3种牧草种子萌发及幼苗生长的影响

以白车轴草、紫云英、紫花苜蓿种子为材料,通过测定发芽率、发芽势、发芽指数、恢复萌发率等指标,研究钙离子浓度对3种牧草种子萌发及幼苗生长的影响,以期为喀斯特地区牧草栽培提供科学参考。研究结果表明:1)低浓度钙离子胁迫(0～0.09 mol·L^-1)对3种牧草种子发芽影响有限,而高浓度钙离子胁迫(0.12～0.15 mol·L^-1)能够明显抑制3种牧草种子萌发,且低浓度钙离子(0.03 mol·L^-1)胁迫可以促进紫花苜蓿种子萌发; 2)白车轴草、紫云英和紫花苜蓿种子发芽指数均随钙离子浓度增加逐渐减小; 3) 3种牧草种子的恢复萌发率表现为紫花苜蓿>紫云英>白车轴草; 4)钙离子浓度明显抑制3种牧草幼苗的生长,低浓度钙离子(0.03 mol·L^-1)有利于紫花苜蓿幼苗生长。可见,紫花苜蓿对高钙环境的适应能力要好于白车轴草和紫云英,是喀斯特地区较为适宜的栽培牧草品种。

Effect of Calcium Stress on Seed Germination and Seedling Growth of Three Forage Grasses

In this experiment,the seeds of Trifolium repens L.,Astragalus sinicus L.and Medicago sativa L.were used as materials,and the effects of calcium ion concentration on seed germination and seedling growth of the three forage seeds were studied by measuring the germination rate,germination potential,germination index,and restoring germination rate,with a view to provide scientific reference for forage cultivation in the karst region.The results showed that 1)low-concentration calcium stress(0-0.09 mol·L^-1)had limited effects on the germination of three forage seeds,while high-concentration calcium stress(0.12-0.15 mol·L^-1)significantly inhibited the germination of three forage seeds,and the low concentration of calcium ions.(0.03 mol·L^-1)stress could promote seed germination of Medicago sativa.2)The germination index of Trifolium repens,Astragalus sinicus and Medicago sativa decreased gradually with the increase of calcium ion concentration.3)The recovery germination rates of the three grass seeds were as follows:Medicago sativa>Astragalus sinicus>Trifolium repens.4)The calcium concentration significantly inhibited the early growth of the three forage seedlings,and the low concentration of calcium ions(0.03 mol·L^-1)was beneficial to the growth of Medicago sativa seedlings.Totally,the Medicago sativa of adaptability to high-calcium environment is better than that of Trifolium repens and Astragalus sinicus and it is a suitable cultivated pasture variety in karst area.