不同种源杉木细根解剖性状的差异分析.

Forty-year-old Chinese fir (Cunninghamia lanceolata) plantations from 16 different provenances in China were selected as the study object to identify the differences in the phenotypes of the anatomical traits of their fine roots, and the characteristics of the responses of the functional traits of fine roots to different geographical environments were analyzed. The fine root diameter (FRD), stele diameter (SD), cortical thickness (CT), ratio of stele to root diameter (SDR), and ratio of cortex to cross-section (CCS) of the fine roots were measured. The differences in the anatomical traits of the fine roots of Chinese fir were compared at the distribution area level, and the correlation between these anatomical traits and environmental factors were examined. The findings revealed significant differences in the anatomical traits of the fine roots among the different provenances (P＜0.05). The FRD and SD of the fine roots of Chinese fir in different locations were ranked in the following descending order: northern belt＞east of middle belt＞center of middle belt＞west of middle belt＞southern belt. The FRD and SD of the fine roots of the trees in Shanghang (Fujian) and Xinyang (Henan) were larger than those in the other provenances, whereas those of the fine roots of the trees in Shangrao (Jiangxi) were the smallest. The CT of the fine roots of Chinese fir in the different areas decreased in the following order: northern belt＞west of middle belt＞east of middle belt＞center of middle belt＞southern belt. The CT of the fine roots of trees in Xinyang (Henan) was thinner than that in other provenances, whereas the fine roots of the trees in Shangrao (Jiangxi) and Luotian (Hubei) showed thicker cortical tissue. The results of redundancy analysis showed that the CT and CCS of the fine roots positively correlated with the soil phosphorus content and significantly negatively correlated with the soil nitrogen content (P＜0.05). The SDR of the fine roots showed a significant positive correlation with latitude (P＜0.05) and a significant negative correlation with soil phosphorus content (P＜0.05). The response characteristics of the anatomical traits of the fine roots of Chinese fir in different habitat conditions differed, indicating that the fine roots of Chinese fir produce variations in functional traits and implement various ecological strategies to adapt to the environmental conditions in different provenances. [ABSTRACT FROM AUTHOR]