In the framework of the BioSolar Cells programme, a joint project between Wageningen University & Research and Solynta explored the possibilities to improve photosynthesis in potato.
Photosynthesis is the energy producing process in plants and it uses the energy of sunlight to convert carbon dioxide from the air into sugars. It is a notoriously complex process and because of its complexity it has not been directly targeted for improvement in plant breeding.
How to improve photosynthesis in potatos
In order to improve photosynthesis, methods for measuring photosynthesis that are suitable for use in plant breeding need to be established, and we need to know how much diversity for photosynthesis is present in breeding material. This kind of study is hardly done in potato because of several restrictions in the traditional way of breeding for this crop.
Solynta generated a new breeding technology that uses a simpler potato genome version. The genome comprises all heritable information of the plant in multiple copies. These copies do not need to be identical and while usual potatoes, which are in the market at the moment, can carry up to four different versions, the genome of this ‘simpler potato’ carries only up to two. This simplicity allows determining the heritable properties of desired characteristics in potatoes faster and easier.
In addition, this technology uses seeds for propagation of potatoes instead of tubers, which enables easier handling of propagation material and the use of procedures and research protocols that have already been established for other crops, which are largely propagated by seed.
To grow potato from seed facilitated the use of the Phenovator, an automated imaging system built at Wageningen University and Research. By an image-based technique, one photosynthetic characteristic was measured in diverse potato materials. The analysis revealed that there was indeed a large variation of photosynthetic responses among the studied potatoes. These differences in photosynthesis could be correlated with the genetic composition of the plants. This type of information would be the basis for a new breeding program to improve photosynthesis in potato.
In a world of changing environments it is important to know how plants, and their photosynthesis, respond to stress; even if photosynthesis is not directly affected by stress, the ease with which photosynthesis can be measured means it is still a useful way of quantifying stress effects on plants. We subjected the plants to three commonly encountered environmental stresses and measured the response of photosynthesis.
We found that the photosynthetic characteristic we measured responded to stress, and so could be used as an early detection tool for stress, saving time in the breeding process. This joint project represents the proof-of-concept that indeed variability in photosynthesis can be used to improve potatoes and opens the door to further in-depth studies and applications.