[Early selection of drought-resistant superior families of Reaumuria soongorica based on the analysis of osmoregulation substances and chlorophyll].

By using 77 families of 3 year-old Reaumuria soongorica seedlings that grew well without injection of any pests and diseases as experimental material, the contents of soluble protein (SP), soluble sugar (SS), proline (Pro) and chlorophyll (Chl) were measured, and their drought resistance was evaluated with principal component analysis and subordinate function method. The results showed that there were great differences in leaf osmolytes and chlorophyll among the 77 families. The soluble protein content varied from 2.14 to 8.60 mg · g⁻¹ FM, the soluble sugar content was from 6.82 to 21.86 mg · g⁻¹ FM, the proline content was from 118.73 to 1494.30 µg · g⁻¹ FM, the chlorophyll a content was from 321.88 to 897.37 µg · g⁻¹ FM, the chlorophyll b content was from 53.65 to 249.04 µg · g⁻¹ FM, chlorophyll (a+b) was from 387.39 to 1146.40 µg · g⁻¹ FM, and the chlorophyll a/b was from 3.46 to 6.42. All drought-resistant indices had significant difference among R. soongorica families, among which the proline content varied most, followed by the soluble sugar content. Evaluated by using the synthesized multi-index, it was found that 12 families showed good drought resistance, with Zhazigou 1-2 and Zhazigou 1-1 performing the best.