大黄果实形态和种子发芽特性的初步研究

Primary study on shapes of fruits and germination characters of seeds of Radix et Rhizoma Rhei

目的:初步了解掌叶大黄、唐古特大黄、药用大黄3种大黄果实形态和发芽特性的差异。方法:收集不同产地的3种大黄的栽培和野生种种子,观察其果实外观形态,检测其种子净度、千粒重、含水量、生活力和发芽率,考察不同温度、不同激素对掌叶大黄种子发芽率的影响。结果:3种大黄果实的外观形态和种子的各种物理特性指标都存在差异,其中药用大黄果实和种子均最大,千粒重也最重,甘肃岷县栽培的掌叶大黄的生活力与发芽率均较高,分别为95.7%和94%,其他种大黄的生活力与发芽率基本保持一致;温度对掌叶大黄种子萌发的影响作用较显著;不同质量浓度的GA3,KT,6-BA对掌叶大黄种子萌发均有一定的促进作用,以50×10-6g.L-1的KT促进作用最佳,其发芽率比对照组提高了18%。结论:3种大黄果实形态和发芽率存在很大差异,不同温度、不同激素处理对大黄种子萌发影响不同,为大黄的鉴定、生长发育及栽培生产提供一定的依据。

Objective： To explore the difference of the shapes of fruits and germination characters of seeds of Rheum palmaturn, R. tanguticum and R. offtcinale. Method： The seeds of three Rheum species including wild and cultivation one were collected from different regions. Character of the fruit＇s appearance were observed. The purification, weights per thousand seeds, content of moisture, seed vigor and different germination rates of Radix et Rhizoma Rhei were measured. The germination rates of the seeds of R. palmature were determined under different temperature and hormone treatment. Result： It was markedly variant in shapes of the fruits, rates of germination and all quality characters of the three category of Radix et Rhizoma Rhei. As reported, the size of the fruit and seed and weights per thousand seeds of R. o gwinale was the biggest. The seed vigor and germination rate of R. palmatum caltivated in Ming county of Gangsu were 95.7% and 94% respectively. The rate of seed vigor was closely correlated with the rate of germination for other species. Results indicated that temperature had some effects on the germination, and there were obvious difference in the active effect of gibberelhn, kinetin and 6-benzyl aminopurine on the germination of the seed. Our experimental results showed that the kinetin concentration of 50 × 10^-6 g·L^-1 had the most active effect, and its rates of germination increase 18 percent than the control one. Conclusion： Significant differences exist in the shapes of fruits, rates of germination of the seeds of Rheum, which are affected by the factors of temperatures and hormones. The result of this study provides scientific evidences for identify, growth and cultivation of Rheum.