Center for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
BMC Plant Biol. 2023 Jan 16;23(1):35. doi: 10.1186/s12870-022-04025-6.
Exogenous GAs have an indeterminate effect on root development. Our current study used female papaya to reveal how the roots and rhizosphere respond to the exogenous application of GA by investigating the transcriptome profile in roots, metabolic profile and microbial community in both roots and rhizosphere of GA-treated and control female papaya. The results demonstrated that exogenous GA treatment enhanced female papaya lateral root development, which gave plants physical advantages of water and nutrient uptake. In addition, it was likely that GA spraying in papaya shoot apices increased the level of auxin, which was transported to roots by CpPIN1, where auxin upregulated CpLBD16 and repressed CpBP to promote the lateral root initiation and development. In papaya roots, corresponding transporters (CpTMT3, CpNRT1:2, CpPHT1;4, CpINT2, CpCOPT2, CpABCB11, CpNIP4;1) were upregulated and excretion transporters were downregulated such as CpNAXT1 for water and nutrients uptake with exogenous GA application. Moreover, in GA-treated papaya roots, CpALS3 and CpMYB62 were downregulated, indicating a stronger abiotic resistance to aluminum toxic and phosphate starvation. On the other hand, BRs and JAs, which involve in defense responses, were enriched in the roots and rhizosphere of GA-treated papayas. The upregulation of the two hormones might result in the reduction of pathogens in roots and rhizosphere such as Colletotrichum and Verticillium. GA-treated female papaya increased the abundance of beneficial bacteria species including Mycobacterium, Mitsuaria, and Actinophytocola, but decreased that of the genera Candidatus and Bryobacter for that it required less nitrate. Overall, the roots and rhizosphere of female papaya positively respond to exogenous application of GA to promote development and stress tolerance. Treatment of female papaya with GA3 might result in the promotion of lateral root formation and development by upregulating CpLBD16 and downregulating CpBP. GA-treated papaya roots exhibited feedback control of brassinolide and jasmonate signaling in root development and defense. These findings revealed complex response to a growth hormone treatment in papaya roots and rhizosphere and will lead to investigations on the impact of other plant hormones on belowground development in papaya.
外源 GA 对根系发育的影响不确定。本研究以雌性木瓜为材料，通过研究 GA 处理和对照的雌性木瓜根和根际的转录组谱、代谢组和微生物群落，揭示了外源 GA 如何影响根和根际的反应。结果表明，外源 GA 处理促进了雌性木瓜侧根的发育，从而使植物具有更好的水分和养分吸收的物理优势。此外，GA 可能通过 CpPIN1 向木瓜茎尖中的生长素运输，增加生长素水平，生长素上调 CpLBD16 并抑制 CpBP，从而促进侧根的起始和发育。在木瓜根中，相应的转运蛋白（CpTMT3、CpNRT1:2、CpPHT1;4、CpINT2、CpCOPT2、CpABCB11、CpNIP4;1）上调，排泄转运蛋白下调，如 CpNAXT1，以促进外源 GA 应用下的水分和养分吸收。此外，在 GA 处理的木瓜根中，CpALS3 和 CpMYB62 下调，表明对铝毒性和磷饥饿有更强的非生物抗性。另一方面，BRs 和 JAs 参与防御反应，在 GA 处理的木瓜根和根际中富集。这两种激素的上调可能导致根和根际中的病原体减少，如炭疽菌和黄萎病菌。GA 处理的雌性木瓜增加了有益细菌的丰度，包括分枝杆菌、Mitsuaria 和放线菌，但减少了 Candidatus 和 Bryobacter 的丰度，因为它需要更少的硝酸盐。总的来说，雌性木瓜的根和根际对外源 GA 的应用做出积极响应，以促进发育和提高胁迫耐受性。用 GA3 处理雌性木瓜可能通过上调 CpLBD16 和下调 CpBP 来促进侧根的形成和发育。GA 处理的木瓜根在根发育和防御中表现出对油菜素内酯和茉莉酸信号的反馈控制。这些发现揭示了在木瓜根和根际中对生长激素处理的复杂反应，并将导致对其他植物激素对木瓜地下发育的影响的研究。
Zotero 插件
