WP2 editorial-Breeding for Resilience
Maria Finckh (WP2 leader, on the right) and Odette Weedon (on the left)
“Breeding for resilience“ is the overall title of WP2. In this work package the main objectives are to study the potential adaptability of Hi-D (high genetic diversity) and various genotypes under changing climatic conditions, as well as to find determinants for early vigour and competitiveness and to identify breeding strategies for coping with multiple stressors. As mentioned by Anders Borgen in the previous editorial, COBRA is more like a research program rather than a research project and as such we will also just touch on a few of the results from our work package thus far.
Three winter wheat (Triticum aestivum L.) CC populations were created in 2001, through collaboration with the Elm Farm Research Centre and the John Innes Institute. In 2007, it was decided to submit one of the CC populations to changes in environments every year. A pattern was developed between eight partners whereby these “cycling” populations would be grown in a plot of >100m2 and sent to the next cycling partner the following year. The original partners (UK, Hungary and Germany) have also maintained their original “non-cycling” populations for comparison. The main hypothesis to be tested is that subjecting genetically diverse populations to varying environments under natural selection should increase general adaptability to climate change.
In addition to the multiplication of the cycling populations, some partners have been able to expand on data collection of the various populations either through having saved seed from successive harvests or through having received seed from various partners in order to compare populations in the same year and in one growing environment. For some partners (e.g. Hungary), funding for additional experimental work is limited, but the cycling and home populations have been multiplied and additional data recorded, which has been invaluable in terms of data comparison on the populations at the different partner sites. The Louis Bolk Institute (Netherlands), for example, has saved seed of the cycling population harvested there every year and has grown them parallel to one another in order to compare the CCP populations over time and in comparison to the reference variety Naturastar. Data collected has included agronomic traits such as yield, TGW and leaf disease assessments, as well as morphological traits such as plant height, flag leaf area etc. Kassel University (Germany) and the Organic Research Centre (UK) have received a number of different cycling populations and have been able to compare them in replicated plots.
The preliminary results of these mixed trials have shown some significant differences between the populations, although not for all traits and not for every partner. A slow adaptation to an ever-changing environment is to be expected as the cycling populations only have one season to adapt before moving on to the next environment, although differences between populations have been noted for some traits such as disease incidence and for morphological traits such as plant height. These significant differences could indicate that the selective pressure has been great enough, in some environments and over time, to cause significant changes between populations. Seed health and quality is also a factor that could play a major role in the differences observed between the populations for a number of traits and further detailed experiments are planned for 2014/2015, which will take this into account and separate the question of actual population differences vs. seed quality.
There have been some interesting results in terms of early vigour and competitive ability of the composite cross wheat populations under organic and conventional management at Kassel University and between generations. Results from Nils-Øve Bertholdsson from the Swedish University of Agricultural Sciences have shown significant changes in root and shoot weight between a number of organic and conventional composite cross wheat populations between the F6 and the F11. In the F11, the organic populations shoot and root weight had increased significantly over the F6 values. This was not the case for the conventionally-managed populations. Over the course of 5 years, the evolutionary changes towards early vigour in the organic populations are most likely due to the combined effects of nitrogen uptake under low-input conditions, increased competition for light, as well as larger seeds. The selection pressure of the differing management systems, as well as the genetic potential of the individual populations has caused significant changes in competitive ability over 5 years.
These initial results from WP2 are very exciting and we are looking forward to further results and discoveries in the 2014/2015 experimental year. The next editorial will be written by Peter Baresel and we look forward to hearing more about the results from WP3 on “Improving Breeding Efficiency”.