Wang Shuguang, Zhan Hui, Li Pengcheng, Chu Caihua, Li Juan, Wang Changming
Key Laboratory for Sympodial Bamboo Research, Faculty of Life Sciences, Southwest Forestry University, Kunming, China.
Front Plant Sci. 2020 Apr 23;11:418. doi: 10.3389/fpls.2020.00418. eCollection 2020.
The physiological function of bamboo shoot sheaths is still unclear. In the present study, we investigated the anatomical and physiological influences of bamboo shoot sheaths on internode elongation by longitudinally striping parts of sheaths. The internodes would bend toward the bare sides during night. The results showed that amounts of water leaked at the cut of shoot sheaths during night, which impeded the increase of water, water pressure and assimilate transport rates, and decreased starch and soluble sugar catabolism in the bare side of the internodes. A higher level of water pressure and sugar metabolism increased the vacuole expansion and promoted the cell expansion in the outer sides as compared to the bare sides. The bending growth of internodes was mainly due to the significant differences in cell expansion, which was led by the difference in water pressure and sugar hydrolysis levels between the inner and outer sides. Bamboo internode elongation mainly relied on the increase of water pressure and soluble sugar concentration. Shoot sheaths played an important role in the rapid growth of bamboo shoots as a controller in water and assimilate transportation. This study gave a new insight into understanding the rapid growth mechanism of bamboo plants.
笋箨的生理功能仍不清楚。在本研究中，我们通过纵向剥去部分笋箨来研究笋箨对节间伸长的解剖学和生理学影响。节间在夜间会向裸露一侧弯曲。结果表明，夜间笋箨切口处有大量水分流失，这阻碍了水分、水压和同化物运输速率的增加，并降低了节间裸露一侧的淀粉和可溶性糖分解代谢。与裸露一侧相比，较高水平的水压和糖代谢增加了液泡扩张，并促进了外侧细胞的扩张。节间的弯曲生长主要是由于细胞扩张的显著差异，这是由内侧和外侧之间的水压和糖水解水平差异导致的。竹节间伸长主要依赖于水压和可溶性糖浓度的增加。笋箨作为水分和同化物运输的控制者，在竹笋的快速生长中起着重要作用。本研究为理解竹子植物的快速生长机制提供了新的见解。
