Studies On Seed Germination And Seedling Physiology Characteristics Of Eight Species Of Seriphidium

Desert plants have formed special germination characteristics and seedlings physiology resistance for survival in the most stressful environment during the plant life cycle. The germination characteristics and seedlings physiology resistance usually vary among the species. They affects not only the growth and development of plants but also the adaptability of plants in response to environment. Seriphidium (Besser) Poljokav are important native plant species in North-west desert grassland of China. They have important value in ecology, Medicine and fodder. To investigate the physiological and ecological applicability of seeds and seedlings of Seriphidium, the thesis studied on the physiology Characteristics of seed in light incubator and potted seedling of eight species of Seriphidium(Seriphidium minchiinense, S. sublessingianum, S. nitrosum, S. transiliense, S. borotalense, S. cinum, S. sawanense, S. kaschgaricum). The content were written about seeds germination characteristics, the physiological resistance of seedlings at different growth stages and the same growth stages. The main results were as followed:1.The weight of seed of eight species were light. The dynamic curve of absorbed water of eight species seeds showed "quick-s low-drop-steady". They absorbed the water quickly in the first hour. The water requirement of germination ranged from 3.97 to 12.52 times of dry weight.2.Germinating amount of seeds showed "bell-shaped". Seeds germination were rapid, and persistent time of germination were 6-12d. Persistent time of germination of S. cinum was the shortest, however S. minchunense, S. borotalense, S. transiliense, S. nitrosum, were longer.3.The order of seeds vigor were S. minchunense>S. sawanense>S. cinum> S. borotalense> S. transiliense>S.nitrosum>S. sublessingianum>S. kaschgaricum.Seed vigor is negatively correlated to the absorbed water quantity.4. Seedlings are high resistance at early stage. They were medium resistance at late stage. They are low resistance at medium stage. Variance analysis indicated that CAT, POD and nonemzyme protective system were the primary responsible for seedlings at early stage, while SOD and nonemzyme protection system were the primary responsible for seedlings at late stage.5.The order of physiology resistance was S. minchunense>S. sawanense> S. borotalense> S. cinum>S. nitrosum>S. transiliense>S. sublessingianum>S. kaschgaricum. This result was in keeping with the morphological characteristics, habitat and seeds vigor of eight species of Seriphidium.