盐胁迫对台湾相思幼苗形态及相关生理指标的影响OACSTPCD

In order to explore the salt tolerance of A.confusa seeds,different concentration gradients of NaCl solution were used to conduct salt stress tests during the seed germination and seedling stages.The results showed that low-concentration NaCl stress could increase the germination rate of seeds.With the increase of NaCl concentration,the germination potential,germination rate,vigor index and germination index of seeds all decreased to varying degrees,and were significantly different from the control.By fitting the regression curve of the germination rate and NaCl stress concentration of A.confusa,it was found that the optimum maximum NaCl stress concentration of A.confusa was 203.87 mmol/L,and the lethal NaCl concentration was 383.16 mmol/L during the germination period.During the seedling stage,leaf fresh weight,stem fresh weight,root fresh weight,main root length,plant height,ground diameter and leaf number showed a downward trend under NaCl stress;The root cap ratio first increased and then decreased;The total root length,total root surface area,total root projected area,total root volume,average root diameter,total root tip number,number of branches,and number of crossings were negatively correlated with the concentration of NaCl;The optimum maximum concentration of NaCl stress during this period was 49.28 mmol/L;the activities of SOD,POD and the contents of MDA,PRO incrersed first and then decreased with the increase of NaCl stress concentration.