刺榆不同器官黄酮类化合物的异质性及其与NSC的代谢耦合关系OA

[Purpose]Hemiptelea davidii(Hance)Planch is a sandland-adapted shrub characterized by high flavonoid content.However,the organ-specific distribution and seasonal dynamics of flavonoids in this species remain poorly understood.This study aimed to elucidate the patterns of flavonoid accumulation and their coordination with non-structural carbohydrates(NSC)across different plant organs.The results provide insight into the resource allocation strategies underlying the ecological adaptation of H.davidii and offer a theoretical basis for its efficient utilization in desert ecosystems.[Methods]To clarify the resource allocation strategies of desert shrubs,we analyzed the temporal dynamics of flavonoids and NSC in a typ-ical shrubland of the Khölgüng Desert.During the 2024 growing season,organ samples(perennial、cur-rent-year and new branches,thorns,leaves,and fruits)were collected periodically.Flavonoid and NSC(starch,soluble sugar)contents were determined via spectrophotometry.Statistical evaluation were con-ducted to evaluate organ-specific and seasonal variation and to identify potential coupling relationships between secondary metabolites and carbon reserves.[Results]Flavonoid accumulation exhibited pro-nounced organ-specific heterogeneity.,Flavonoid concentrations were significantly higher concentrations in leaves with median values of 38.51 mg·g-1 and 35.26 mg·g-1 in current-year and perennial leaves,re-spectively,and in current-year thorns,with a median value of 27.61 mg·g-1,than in branches,where medi-an values were 7.31 mg·g-1 and 8.85 mg·g-1 in current-year and perennial branches(p＜0.001).Seasonal accumulation followed a bimodal pattern,with peaks in June and September and a marked decline during the vigorous growth phase in August.New organs demonstrated greater seasonal variability than perenni-al organs.Correlation analysis further revealed organ-specific metabolic strategies.Flavonoids in current-year thorns were highly significant positive correlation with NSC and its components,including starch and soluble sugars(p＜0.01),indicating a"cooperative storage-defence"mode.In contrast,flavonoids in new branches were significantly negatively correlated with soluble sugars during the peak growth period(p＜0.05),suggesting a"growth-defence trade-off".[Conclusion]The organ-specific heterogeneity,seasonal dynamics,and divergent relationships between flavonoids and NSC enable H.davidii to optimize carbon allocation among growth,defense,and storage.This multifaceted strategy reveals an important ecological adaptation mechanism under harsh desert conditions and provides a physiological basis for the persist-ence and sustainable utilization of this species in desert ecosystems.