Abstract:

Growth, photosynthetic pigment content, and mineral nutrient element content of heteromorphic plants of different populations of Suaeda corniculata were measured under similar cultivation conditions to explore the physiological and ecological mechanisms of S. corniculata adapting to saline-alkali environments. The results showed that: (1) growth, photosynthetic pigment content, salt ion content, and N, P, K content of brown and black seeds had similar responses to the same environment, but there were significant differences in growth and physiological and ecological indices for heteromorphic seeds across populations. (2) Aboveground dry weight was significantly affected by population type, while root dry weight was not. The photosynthetic pigment content Cha, Chb, Cha+b, and Car were not significantly affected by population type and plant type, suggesting a similar photosynthetic capacity of plants within the population. (3) There were significant differences in Na⁺, K⁺, Ca²⁺, Cl^-, SO4^2-, P and K contents between Xinjiang and Inner Mongolia populations, indicating that there were differences in osmotic maintenance ability among different populations. (4) The differences in aboveground growth of S. corniculata in different populations were related to ion content and absorption and utilization of P and K, but not to nitrogen absorption capacity and photosynthesis. In conclusion, studies have shown a synergistic relationship between salt ion absorption systems in heteromorphic plants of different populations, which is closely related to mineral element P, K content and may be an important physiological mechanism of S. corniculata adapting to environmental change.

Key words: heteromorphism, mineral elements, Suaeda corniculata, photosynthetic pigment content