Enhancing the genetic resources of roots, tubers & bananas

Flagship Project 1 (FP1) ‘Enhanced genetic resources‘, will make use of plant biology, structural and quantitative genetics – or the study of genes that dictate a plant’s architecture, tolerance to pests or other stresses and many other traits – and other disciplines to help enhance crops’ hardiness, architecture or nutritional profile.

Biofortification – enhancing crops’ nutritional content through exploration of their genes – is one of many reasons to tap into crops’ genetic resources. The process of breeding roots, tubers and bananas that can help more people absorb increased quantities of nutrients essential for human health begins with closely examining the genes responsible for their accumulation in these crops, is a key focus of FP1.

Others include breeding crops that can better tolerate drought or that can use photosynthesis more effectively, says Luis Augusto Becerra, a Principal Research Scientist at the International Center for Tropical Agriculture (CIAT) and the leader of the flagship. This body of the work seeks to tap into diverse genetic materials to explore new ways of enhancing crops for greater health benefits and agricultural improvements using a trove of untapped genetic resources stored at the CGIAR genebanks.

Scientist inspects Bioversity International’s in vitro banana collection at the International Transit Centre. Photo: N. Capozio/Bioversity International

Climate change imposes new stressors on RTB and other crops, he points out, so the ability to develop, say, orange-fleshed sweetpotato that manages to thrive on less water but still is highly productive is a prized goal. Similarly, increased resistance to virus diseases in cassava keeping its user-preference attributes.

Climate change will make the growing environment for our crops more difficult, Becerra points out. Adapting them to grow in spite of changing ecological and environmental factors is essential as a bulwark against global hunger, an ever more pressing issue as the global population grows.

By way of example, crops whose genes have been bred for hundreds of years to grow longer roots that reach deeper into soil for water will have a better shot at surviving – and therefore at nourishing more people or providing more saleable crops for the struggling smallholder.

Cassava is a hardy crop that can grow in marginal soils and tolerate drought. Photo G.Smith/CIAT

Technological advances are key when it comes to breeding better ‘parent’ plants for stronger, hardier, more nutritious progeny. “We will be using leading-edge techniques to not only improve breeding accuracy, but also to shorten selection cycles,” says Becerra. That way, more promising candidates can be targeted more quickly for development in other flagships. FP1’s research goals are key to delivering the next generation of crops that will respond to the demand for more nutritious food.

As an example, the team might cross-breed two parent plants to see if their resulting progeny can withstand a more alkaline soil. If and when a new variety shows promise, the team will work with others to help test the plant in different pilot settings under differing growing conditions (note that work in one region to be applicable to that of another if weather or climate factors are similar to one another). Ultimately, a hardier plant stands to become available to a larger group of farmers, who in turn can raise their household income and improve the overall economic health of their community; Flagship Project 5 on ‘Improved livelihoods at scale’ would be instrumental in scaling up efforts to make the new plant more broadly available to all stakeholders.

Becerra notes that FP1 also seeks to support and increase knowledge about genebank collections, including those held at Bioversity International, CIAT, the International Potato Center (CIP) and the International Institute of Tropical Agriculture (IITA) and those at other facilities in Colombia, Norway and elsewhere.

For instance, CIP’s genebank, featuring some 11,000 specimens, is clonal: it primarily stores plants, not seeds. Therefore, these collections are stored and maintained differently from those in seed-based genebanks. Part of FP1 will include examining different methods for “backing up” the roots, tubers, potato and sweetpotato plants in CIP’s collection to other sites around the world. Making copies of this genetic material serves as another layer of protection against threats to global food supplies, either natural or man-made.

In the face of climate change and other factors, enhancing greater plant diversity is perhaps the overarching goal of FP1, Becerra notes. “Our goal in FP1 is to use state-of-the-art technology to better support researchers, farmers, consumers, policymakers and other stakeholders along the value chain.”

This is the final blog showcasing the new Flagship Projects of the CGIAR Research Program on Roots, Tubers and Bananas. By Amy Rogers Nazarov