萌芽前'冬枣'枝条含水率及耐寒生理指标变化分析OACHSSCD

To clarify the physiological responses of water content and cold resistance indicators of Ziziphus jujuba Mill.cv.'Dongzao'branches before sprouting to low-temperature stress,and to provide a reference basis for the collection of scions in the Alar Reclamation Area.During the pre-budbreak period of Ziziphus jujuba Mill.cv.'Dongzao'from March 18th to April 15th,2024,one-year-old branches were collected daily in this research.Moisture content,soluble sugars,soluble proteins,malondialdehyde(MDA),and free proline were measured and analyzed for their response to external low-temperature conditions.The cold resistance of the branches was comprehensively evaluated in combination with the grey relational degree.The results indicated that on April 10th,2024,green spots appeared on the tips of the Ziziphus jujuba Mill.cv.'Dongzao'in the Alar,and they gradually entered the germination period.All full sprouting achieved by April 13th.Branch moisture content remained relatively stable from April 2th to April 10th,and reaching a minimum of 33.09%on April 7th.Soluble sugar content gradually increased from March 24th,peaking at 11.24%in the branches on April 10th before decreasing markedly upon sprouting.Soluble protein levels exhibited overall stability but showed a declining trend;the lowest value recorded was 3.11 mg∕g on April 10th.In the branches,MDA content stabilized between April 1th and April 10th,with a minimum of 0.000 50 mg∕g observed on April 4th.From March 29th to April 10th,the content of free proline in the branches showed an overall downward trend with a relatively small change range,and the average content of free proline was 1.891 mg∕g.Through Ggrey relational analysis re-vealed that the comprehensive evaluation of cold resistance indicators was highest during the eight days before germination(Apri 2-10th;average temperature:9.0-16.5℃).The overall water content and soluble sugar levels were relatively high and stable,the MDA concentrations was extremely low,and relatively stable soluble protein levels throughout this timeframe.This study provides a scientific theoretical basis for the optimal scion collection period for'Dongzao'.