Differential Responses to Simulated Precipitation Exhibited by a Typical Shrub and a Herb Coexisted in Hunshandak Sandy Land Allelopathy of Aqueous Extracts from Tamarix spp.on Seed Germination and Seedling Growth of Salsola collina Pall. A new flavone glycoside from Salsola collina Developmental and Anatomical Studies on the Seedling of Salsola collina Studies on chemical constituents of Salsola collina COMPARATIVE STUDIES ON CRYSTAL IDIOBLASTS OF FIVE DESERT C4 PLANTS