Project

Genotype-specific effects of drought and N stress on potato growth, development and quality

Potato is one of the world’s most important food and industrial crops. Unfortunately, climate change and legislations aiming at reducing fertiliser use, put pressure on potato production. In this project, we try to elucidate the effects of combined water and N deficits on the growth and development of potato tubers. Currently, we are looking into the effects of these stresses on the development over time of a variety of potato cultivars and will implement our findings in the WOFOST 8.2 crop growth model. Doing a thesis within this project, will entail either fieldwork or modelling or both.

Project description

Potato is one of the world’s most widely produced crops and has multiple purposes ranging from food to industrial applications. Unfortunately, potatoes are also notoriously susceptible to abiotic stresses, like drought, and potato production is associated to large losses of nitrogen (N) to the environment. As climate change is projected to cause more frequent and severe drought events and legislation is steering towards the reduction of N losses, it is crucial to find ways to maintain high, good-quality yields under water and N limited conditions.

In this project, we try to elucidate the effects of combined drought and N deficiency on the growth, development and quality of potatoes and try to implement these findings in the existing crop growth model WOFOST 8.2. We investigate a wide variety of potato cultivars to find cultivar-specific characteristics that may determine their response to drought and N deficiency. The effects of the treatments on the final tuber yield and quality of our entire range of cultivars has already largely been analysed. We are currently attempting to analyse the tuber development over time and try to use this to improve and add functionalities to WOFOST 8.2.

Specific topics that are open for thesis projects are for instance:

  • Investigating the effects of drought and N stress on tuber development over time.
  • Analysing N partitioning between different plant organs throughout the season.
  • Comparing tuber development in the field with model outcomes to pinpoint parameters for model calibration.
  • Modelling the development of tuber DM content and tuber size distribution.

As I would like to stimulate creativity, I am also open to any other suggestion that may interest you and falls within the possibilities of this project. Feel free to contact me to discuss any ideas.

Objectives and methods

By analysing data collected in the field, we aim to find potential relationships between field conditions and tuber development over time. This will allow us to improve the WOFOST 8.2 crop growth model and add functionalities to predict tuber quality characteristics.

Tuber development of a set of potato cultivars is monitored over time by means of periodical intermediate harvests. The harvested samples are analysed for various tuber quality characteristics, dry matter production and N content. In the end, this will leave us with a large data set that, after analysis, can give us valuable insights into the genotype-specific responses of potato to combined abiotic stresses and can be used in crop growth modelling. In addition, data on aboveground development will be available as part of another project, and can be used to complement any analysis or modelling endeavor.

Expectations

Depending on the topic, this project will include a mix of hands-on fieldwork, data analysis and modelling, such as:

  • Periodically harvesting potato plants;
  • Processing potato tuber samples;
  • Analysis of the self-collected data and data collected in previous seasons;
  • Calibrating and evaluating the WOFOST 8.2 crop growth model for growth under combined water- and N-limited conditions;
  • Developing functions
    for tuber quality prediction to be implemented in WOFOST 8.2.

Required skills

Depending on the type of project, the following skills could be useful, but there are no strict requirements:

  • Experience with field experiments;
  • Data analysis skills (e.g., by having completed Advanced Statistics or an equivalent course);
  • Experience with dynamic crop growth models;
  • Programming in R and/or Python.

Types of research / work

Again, depending on the type of project, a thesis will consist of a mix of fieldwork, data analysis and modelling.

Period

Preferably starting in May - July, but other starting dates can be discussed.

Location

  • The fieldwork takes place on a trial field at experimental farm SPNA Kollumerwaard in Friesland. Whenever this is necessary, accommodation and transport will be accounted for.
  • Part of the tuber processing will be performed at Unifarm in Wageningen.
  • For office work, you will be appointed a flex desk in
    our office building Radix Nova.

Supervisor