Phosphorus-induced change in root hair growth is associated with IAA accumulation in walnut


  • Yongjie XU Hubei Academy of Forestry, Forestry Road, Wuhan 430075; Yangtze University, Tibet Plateau Walnut Industry Research Institute, Shannan 540500 (CN)
  • Chunyong XU Hubei Academy of Forestry, Forestry Road, Wuhan 430075; Yangtze University, Tibet Plateau Walnut Industry Research Institute, Shannan 540500 (CN)
  • Dejian ZHANG Hubei Academy of Forestry, Forestry Road, Wuhan 430075; Yangtze University, Tibet Plateau Walnut Industry Research Institute, Shannan 540500; Yangtze University, College of Horticulture and Gardening, Jingzhou 434025 (CN)
  • Xianzhen DENG Hubei Academy of Forestry, Forestry Road, Wuhan 430075; Yangtze University, Tibet Plateau Walnut Industry Research Institute, Shannan 540500 (CN)



IAA, phosphorus, root hair, walnut


 DOI: 10.15835/nbha49412504

Walnut, an important non-wood product forest tree, has free root hairs in orchards. Root hairs are specialized cells originating from the root epidermis that are regulated by plant hormones, such as auxins. This study was conducted to evaluate the effect and mechanism of phosphorus stress on root hair growth of walnut (Juglans regia L.) seedings by auxin (IAA) biosynthesis and transport. Both low phosphorus (LP) and no phosphorus stresses (NP) heavily decreased plant height, leaf number, total root length, root surface, shoot and root biomass, and root nutrient contents. The LP treatment significantly increased root hair growth, accompanied with up-regulation of the positive regulation root hair growth gene JrCPC and down-regulation of the negative regulation root hair growth gene JrTTG1, while the NP treatment had opposite effects. The root IAA level, IAAO activities, IAA transport genes (JrAUX1, JrLAX1, and JrPIN1), and the biosynthesis genes (JrTAA1 and JrTAR1) were increased by the LP treatment, while the NP treatment decreased all of them. Interestingly, the auxin biosynthesis gene CsYUCCA1 was not affected, which suggested that P mainly affects root hair growth of walnut by regulating auxin transport, and then affects root nutrient absorption and plant growth.


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How to Cite

XU, Y., XU, C., ZHANG, D., & DENG, X. (2021). Phosphorus-induced change in root hair growth is associated with IAA accumulation in walnut. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, 49(4), 12504.



Research Articles
DOI: 10.15835/nbha49412504