2-year Post-doctoral Research Position (Soybean root ideotypes conferring tolerance to combined drought and low phosphorus stresses)
Root Biology Group
South China Agricultural University, Guangzhou
In association with the LEC-SCAU-GIG Joint Institute of the Environment
2-year Post-doctoral Research Position
Soybean root ideotypes conferring tolerance to
combined drought and low phosphorus stresses
Supervisors: Prof Ian Dodd (Lancaster Environment Centre, Lancaster, UK)
Prof Jiang Tian (South China Agricultural University, Guangzhou, China)
Background: While China has had remarkable success in producing sufficient food for its large population, accelerated economic development has increased demand for meat and dairy products. Livestock weight gain is promoted by consumption of vegetable proteins, of which the best is soy meal. Although China is the centre of origin of soybean domestication, it imports substantial quantities of soy meal and there is a national drive to increase domestic production. Unless soy displaces cereals within crop rotations, this may require growing crops under suboptimal conditions of low water availability and/or phosphorus (P), particularly in the acidic soils of south China. Moreover, since over-use of P and irrigation water causes environmental problems, there is increasing pressure on farmers to limit their use of these finite and/or transiently scarce resources.
Plant root systems show morphological (e.g. increased root hair length and density, lateral root proliferation, tap root elongation), molecular and physiological (e.g. increased expression of phosphate transporter genes, exudation of phosphatase enzymes and organic acids) adaptations in response to low P stress. The Root Biology Group at South China Agricultural University (SCAU) has increased soybean tolerance to low P by identifying genetic diversity in soybean root traits, developing recombinant inbred line populations by crossing parental lines with divergent tolerance to low P stress, and by overexpressing phosphate starvation responsive genes under the control of root-specific or constitutive promoters (Yao et al., 2014a; b; Liu et al., 2016; Xue et al., 2017). Work continues to understand the relative costs and benefits of these approaches, in pyramiding traits to improve P acquisition.
Some of these traits improving P acquisition may have positive or negative impacts on plant tolerance to water deficits, since vertical gradients of phosphorus and water availability are often opposite in field soils. Thus shallow roots (which enhance access to the higher P concentrations in surface soil layers) may limit rooting depth, thus diminishing the crop’s ability to acquire water at depth in the soil profile. Moreover, a higher proportion of roots in the upper layers may increase root production of chemical signals such as ABA, that limits leaf gas exchange and leaf growth (Martin-Vertedor & Dodd, 2011). Alternatively, increased root hair length (which assists P acquisition from the soil) may enhance plant water uptake, although the relative importance of root hairs in water uptake is uncertain (Diatloff & Dodd, 2016). “Designer root systems” for low-phosphorus soils that also experience fluctuating water availability need to consider the relative costs and benefits of both P and water acquisition.
Plants roots adapt to their local environment by altering their phytohormone production, which can have local effects in the roots (eg. changes in hydraulic conductance) and can be exported from the roots to alter shoot physiology (eg. stomatal closure). Root-specific overexpression of phytohormone biosynthesis genes has increased crop yields of plants grown in saline soil (Albacete et al., 2015), but it is uncertain whether this approach can be more widely applied under other stresses.
Using the substantial genetic resources in soybean available at SCAU, you will:
Identify variation in multiple root traits under individual and combined low P and drought stresses, and determine their genetic regulation
Transform soybean with hormone biosynthesis genes to evaluate the impacts on water and P acquisition
Conduct field experiments to evaluate the relative success of different approaches to increasing soybean tolerance to individual and combined low P and drought stresses
Join an exciting research environment. You will join the large and vibrant Root Biology Group at South China Agricultural University, while also being affiliated with the Plant Water Stress Research Group at the Lancaster Environment Centre. Research infrastructure and resources will be available for this project at the newly appointed ‘Joint Institute for the Environment’ (JIE) located in SCAU in Guangzhou, China – at which you will be primarily based – and within the Lancaster Environment Centre, UK. We envisage time split between the Chinese and UK organisations, though successful candidates will have to spend a minimum of 12 months in China before 1st April 2019.
Be part of the EU SEW-REAP research community. This post is one of three within the framework of the European Union’s SEW-REAP (Addressing food Security, Environmental stress and Water by promoting multidisciplinary Research EU And China Partnerships in science and business) project which aims to provide solutions to the Agri-Food-Water-Environment Nexus within China, which will base 3 postdoctoral positions at SCAU. Additionally, SEW-REAP has already based 9 PhD-level researchers within China (most of whom are based at the JIE).
Who should apply: You should have a PhD in Plant Sciences (e.g. molecular biology, biochemistry or physiology) with an interest in crop phenotyping. You must have proven capacity for creative, high-quality research, evidenced by your publication record, which must be commensurate with the opportunities provided.
Due to the nature of funding (postdoctoral salary in China which is supplemented by a contribution from the EU SEW-REAP project), only UK / European citizens are eligible to apply.
A willingness to embrace new research challenges while living in China for at least 1 of the 2 years is essential.
Funding: The PDRA will be an employee of the South China Agricultural University (SCAU). A 2-year post-doctoral research assistant (PDRA) salary (equivalent to €17,805 per annum at today’s rates) will be paid by SCAU and supplemented with RMB 1500 (€190) per month for accommodation costs in China. Income from SCAU will be taxed and paid in China. 12 months living and travel expenses are also available from the SEW-REAP programme, at a rate of €1680 free of tax per calendar month spent in China. Together, the combined funding for this post is approximately €27,885 p.a. averaged across the two years.
Deadline for applications: [3rd November 2017]
Provisional Interview Date (by Skype if necessary): [10th November 2017]
Start Date: 1 January 2018
Application process: Due to the limited time between the closing date and the interview date, it is essential that you ensure references are submitted by the closing date or as soon as possible.
A Albacete, C Martínez-Andújar, A Martínez-Pérez, AJ Thompson, IC Dodd, F Pérez-Alfocea (2015) Unravelling rootstock x scion interactions to improve food security. Journal of Experimental Botany 66, 2211-2226.
IC Dodd, E Diatloff (2016) Enhanced root growth of the brb (bald root barley) mutant in drying soil allows similar shoot physiological responses to soil water deficit as wild-type plants. Functional Plant Biology 43, 199-206.
AI Martin-Vertedor, IC Dodd (2011) Root-to-shoot signalling when soil moisture is heterogeneous: increasing the proportion of root biomass in drying soil inhibits leaf growth and increases leaf ABA concentration. Plant, Cell and Environment 34, 1164-1175.
Xue Y, Xiao B, Zhu S, Mo X, Liang C, Tian J*, Liao H (2017) GmPHR25, a phosphate starvation up-regulated GmPHR member controls phosphate homeostasis in soybean. Journal of Experimental Botany. doi:10.1093/jxb/erx292
Liu P, Xue YB, Chen ZJ, Liu GD*, Tian J* (2016) Characterization of purple acid phosphatases involved in extracellular dNTP utilization in Stylosanthes. Journal of Experimental Botany 67,4141-4154.
Yao Z, Tian J*, Liao H (2014a) Comparative characterization of GmSPX members reveals that GmSPX3 is involved in phosphate homeostasis in soybean. Annals of Botany114,477-488.
Yao Z, Liang CY, Zhang Q, Chen ZJ, Xiao BX, Tian J*, Liao H (2014b) SPX1 is an important component in the phosphorus signalling network of common bean regulating root growth and phosphorus homeostasis. Journal of Experimental Botany 65,3299-3310