More than 250 PhD students receive their PhDs at WUR every year. It is impossible to describe and summarize all these theses. In the column ‘PhD theses in a nutshell’ the selection of our science editors is briefly presented.
Fermented raw milk
Mabisi is a traditional Zambian milk product that results from the spontaneous fermentation of raw milk. Thelma Sikombe studied the taste and production of this local product with a view to larger-scale production than at the household level. There is potential, is her conclusion. She isolated the main flavour substances and microbes involved in the fermentation. A big advantage of mabisi is that it keeps for two weeks without refrigeration. That can help with food security in Zambia.
Traditional mabisi production.
Thelma W. Sikombe. Supervisors Eddy Smit and Sijmen Schoustra
Dry diversity
There is a surprising amount of biodiversity in deserts. And it is surprisingly badly documented. Zakaria Hatim, from Egypt, has developed a new system of classification for vegetation groups and plant communities, for the deserts of North Africa and the Arabian Peninsula. Climate change is a threat to desert plants like many others, especially those in low-lying and salt deserts. Mountainous deserts, on the other hand, seem to be a relatively safe refuge for threatened vegetation.
Deserts unveiled.
Mohamed Zakaria Hatim. Supervisor Joop Schaminée
Flowering time
How plants react to light and temperature is partly determined by genes. But so-called epigenetic factors, which determine whether a gene gets switched on, are involved as well. One of the things Suze Blom studied was the role of non-coding RNA. These are transcripts of DNA that do not code for proteins. She identified seven long fragments of that RNA, which play a role in regulating flowering when the ambient temperature changes. This is just the tip of the iceberg.
Non-coding and epigenetic regulators of ambient temperature sensitive flowering.
Suze Blom. Supervisors Richard Immink and Gerco Angenent