Allozyme Diversity and Population Differentiation in an Endangered Plant,Ammopiptanthus nanus(Leguminosae) Observation on the Chromosome Behavior at Meiosis of Ammopiptanthus nanus Spatial distribution of AM and DSE fungi in the rhizosphere of Ammopiptanthus nanus Extraction, Separation and Measuration of the Thermal Hysteresis Activity of Antifreeze Proteins from Ammopiptanthus nanus (Leguminosae) CHARACTERISTICS OF AMMOPIPTANTHUS NANUS SEED AND FACTORS AFFECTING ITS GERMINATION Flowering Phenology of an Endangered Plant Ammopiptanthus nanus Study for the Ecological Environment and Vulnerable Reasons of the Ammopiptanthus nanus