[Differences of Cynomorium songaricum seed quality and mutual parasitism in different host plants]

In natural conditions, fully ripe Cynomorium songaricum seeds parasitize in Nitraria tangutorum or N. sphaerocarpa or N. sibirica or Zygophyllum xanthoxylom and Peganum harmala, were used in this study to research the morphological characteristics, embryo rate, seed viability, 1 000-grain weight, purity, water content and the seeds of different host parasitic relationship with each other. The results showed that the morphology, color and surface characteristics of the C. songaricum seeds are very similar in different hosts. According to the seed morphology can not be judged on its host. For the host to N. tangutorum or Peganum harmala or N. sibirica, we should choose the round hole screen less than 0.923 1 mm and larger than 1.066 2 mm to cleaning seeds. For the C. songaricum seeds parasitic in N. sphaerocarpa, the choice of slightly less than 0.926 1 mm and larger than 0.985 3 mm round hole screen to cleaning. For the parasitic seeds in Z. xanthoxylom, less than 0.751 3 mm and slightly larger than 1.035 3 mm round hole screen could be used. Highy significant correlation was found among the morphological indexes in C. songaricum seeds (P < 0.01). Morphological indexes and 1 000-grain weight were significantly correlated (0.01 < P < 0.05), but with the seed viability and the embryo rate were not found significant correlation. Grain weight is not related with the seed viability and the Fully mature C. songaricum seed viability is high and water content is low. The difference of the habitats and the host plants should be considered in the seed quality assessment and classification. The C. songaricum seeds on host plants are not selective, and the C. songaricum seeds from the host plants could be parasitized in other host plants.