[Effect of Water Extracts from Rhizosphere Soil of Cultivated Astragalus membranaceus var. mongholicus on It's Seed Germination and Physiological Characteristics].

Objective: To explore the relationship between continuous cropping obstacle and autotoxicity of Astragalus membranaceus var. mongholicus.

Methods: Distilled water(CK), water extracts of rhizosphere soil(50, 100, 200 and 400 mg/mL) were applied to test their effect on early growth and physiological characteristics of Astragalus membranaceus var.

[Construction and immunogenicity analysis of the attenuated recombinant Salmonella typhimurium strains expressing Echinococcus granulosus Eg95 antigen].

Objective: To study the feasibility of using attenuated Salmonella typhimurium as carrier for oral immunization of Eg95 antigen of Echinococcus granulosus.

Methods: The recombinant plasmid pYA3341-Eg95 was constructed by inserting the Eg95 gene into expression vector pYA3341, and identified by the methods of PCR and enzyme digestion. The recombinant plasmid pYA3341-Eg95 was electro-transformed into attenuated S.

[Effect of drought stress on growth and physiological-biochemical characteristics of Stellaria dichotoma].

A pot experiment was conducted to study effect of drought stress on leaf physiological characteristics and growth of one year old Stellaria dichotoma seedlings. The result showed that plant height and shoot dry weight significantly decreased with decrease in soil water content; however, root length and root dry weight increased at light drought stress and decreased at severe drought stress. The result also showed that with the decrease of soil water content, proline content in S.

[Autotoxicity of aqueous extracts from plant of cultivated Astragalus membranaceus var. mongholicus].

Objective: To exploring the relationship between continuous cropping obstacle and autotoxicity of Astragalus membranaceus var. mongholicus, autotoxic effect of plant aqueous extract were determined.

Methods: Distilled water (CK), aqueous extract of plant, including root, stem and leaf (12.