血叶兰幼苗对干旱胁迫的生理响应及其抗旱性指标筛选OA

In order to investigate the tolerance of Ludisia discolor to drought stress,the experiments potted water control to simulate drought were used to study the changes of growth,physiological and biochemical indicators,and bioactive components in L.discolor seedlings with around 6 months of age under different water treatments.The main response factors to drought resistance were evaluated through correlation analysis(CA)and principal component analysis(PA),which would provide some references for the water management under conservation and cultivation of L.discolor.The results showed that with the increase of drought severity,the height of L.discolor seedlings showed a downward trend compared to the control group,but there was no significant effect on stem thickness.The relative water content of leaves decreased,and the content of chloroplast pigment(Chl)first increased and then decreased,while the content of anthocyanin(ACN)showed an upward trend.Under drought stress,the activities of peroxidase(POD)and superoxide dismutase(SOD)showed a trend of first increasing and then decreasing.The contents of malondialdehyde(MDA),soluble sugar(SS),and the bioactive substances such as total flavonoids(TF),total phenols(TP),and polysaccharides(PS)all increased.Through correlation analysis and principal component analysis,it was found that MDA,SS,PS,and relative water content could be used as the preferred evaluation indicators,and in addition,stem thickness and SOD activity could be used as auxiliary indicators for drought resistance evaluation in L.discolor.In summary,the results indicated that moderate drought stress(soil moisture content 50%-55%)could promote the synthesis and accumulation of osmotic regulating substances and bioactive components of L.discolor,At the same time,to improve the quality of L.discolor,it was recommended to carry out short-term severe drought(soil moisture content 15%-20%)before harvest so that the biological activities of L.discolor could be enhanced.These findings had practical guiding significance for cultivation management.