Recently, a research paper entitled “Local and systemic responses conferring acclimation of Brassica napus roots to low phosphorus conditions” was published in the Journal of Experimental Botany by HZAU’s team of plant nutritional biology from the College of Resources & Environment.
Experiments of Pi efficient mechanism in a split-root system
Oilseed rape (Brassica napus L.) is one of the most important oil crops cultivated in China which demands a large amount of Phosphate (Pi) and is extremely sensitive to Pi deficiency. Local Pi application can not only reduce Pi fixed by soil, but also promote the growth and development of crop roots, thus improving the Pi absorption efficiency and increasing yield. The regulatory network of root system in response to external Pi supply includes local and systemic signals. Local responses are modulated by the internal Pi availability in the growth medium, while systemic responses depend on the external Pi concentrations in the plant. Given that Brassica napus L. is an allotetraploid crop with complex genetic background, there are few studies on the molecular mechanism of local responses to Pi supply in this species.
In this study, with the purpose of analyzing the changes of root architecture of Brassica napus in responses to local Pi supply, a split-root system was employed to simulate the non-uniform distribution of Pi in the soil in Agar culture system. The results showed that the root architecture was modulated by systemic signals and lateral root (LR) growth was regulated systemically by non-uniform Pi distribution, by increasing the second-order LR(2°LR) density in compartments with high Pi supply but decreasing it in compartments with low Pi availability. Transcriptomic profiling identified groups of genes regulated, both locally and systemically, by Pi starvation. Among them, the number of systemically induced genes was greater than the number of genes locally induced, and abscisic acid (ABA), jasmonic acid (JA), sugars, and reactive oxygen species (ROS) were confirmed involving in the systemic Pi starvation response. This research provided new insights into the molecular and physiological basis of root plasticity.
Li Yalin, a doctoral student of HZAU, is the first author of the paper. Professor Shi Lei is the corresponding author. Contributing researchers include Wang Chuang, Ding Guangda and Xu Fangsen (three professors at HZAU), Wang Sheliang and Cai Hongmei (two associate professors at HZAU), John P. Hammond (a professor at University of Reading, UK), Philip J. White (a professor at James Hutton Institute, UK), Sergey Shabala (a professor at University of Tasmania, Australia), Yu Min (a professor at Foshan Institute of Science and Technology), and doctoral students Yang Xinyu, Liu Haijiang and Wang Wei of HZAU. This research was supported by the National Natural Science Foundation of China (grant nos31972498 and 32172662) and the National Key R&D Program of China (grant no.2017YFD0200200).
Source: http://news.hzau.edu.cn/2022/0602/63522.shtml
Translated by: Liu Binbin
Supervised by: Xie Lujie
