Toward a More Resilient Chickpea: Q&A with Innovation Lab Director Doug Cook
This interview with Doug Cook, Director of the Feed the Future Innovation Lab for Climate Resilient Chickpea, is the first in a series for climate, weather and resilient agriculture month this May on Agrilinks.
Housed at the University of California, Davis, the Innovation Lab for Climate Resilient Chickpea emphasizes the crop-based traits of climate resilience and nutrition, focusing genetic improvement on the needs of smallholder farmers in Ethiopia and India. In both countries chickpea is key to food security, providing a vital source of protein, nutrition and income. Click here to download a factsheet.
Agrilinks: What does the lab focus on and why does it matter?
Cook: We focus on abiotic stress (drought, heat and cold) as well as biotic stress (pests and pathogens) in chickpea that reduce yields by up to 100 percent.
Heat is a significant problem, especially in India where the majority of chickpea is grown. As it is being displaced in the northern part of India by rice and wheat, chickpea is moving further south, where it is encountering hotter conditions than ever. Heat impacts the development of viable pollen, and the crop becomes sterile at temperatures much above 35 degrees Centigrade.
We’ve identified genotypes that are completely tolerant to heat, which is a huge breakthrough. Now we need to identify the genomic regions that control those traits and use that advanced molecular understanding to more precisely and rapidly integrate those wild traits into cultivated species.
Agrilinks: Tell me about a few of other successes your lab has had to date.
Cook: One major success has been the migration of genetic diversity from wild material; we have greatly expanded the range of traits for crop improvement.
Rational surveying of wild material is becoming an acceptable paradigm in breeding; the trick is having adequate resources to do it. There are lots of efforts to collect, preserve, curate, understand and utilize wild material, but it’s rarely been used systematically and on a large scale like this within a single project. Wild material has been used effectively in maize and rice, but that’s the product of many years of work and different investigators under different projects, so it lacks the continuity of doing it all at once.
Another success has been in battling a pathogen called Ascochyta blight. It’s a foliar fungus, and it’s a problem in parts of the world where chickpea is grown in high humidity, including when rain occurs in the growing season. In Ethiopia, Ascochyta blight will cause 100 percent loss if there is an unusually late rain during vegetative development of the crop.
In Southeastern Ethiopia, which was devastated by this blight last year, we ran trials to expose different lines to the pathogen and identified numerous wild lines that are tolerant to it. It is a significant breakthrough because of how the pathogen operates. When it goes through sexual reproduction, it basically reshuffles its genome, which gives the pathogen the ability to evolve relatively quickly and often overcome resistance.
There is a solution to this that is well established in other crops, such as stem rust in wheat, which also evolves quickly. Instead of deploying a single gene in the host that the pathogen will likely overcome, you deploy multiple genes. In this way, you can stack resistance genes in a host and affect the stability and durability of resistance, which we are pursuing right now.
There are numerous examples of where we have made that kind of progress. Take for example pod borer resistance, another serious problem in chickpea. There is zero resistance in cultivated species, but we have identified many different traits that we’ve made substantive progress on. We just published a paper in Nature Communications, one of the world’s leading scientific journals, describing this.
One of the most significant outcomes from our project, however, is the human resources we’ve developed, particularly training scientists in the developing world. Now it’s a matter of taking the people we’ve trained and giving them an opportunity to change institutional culture and train others within their institutions. We can generate a lot of data, but until we have new varieties on the shelves, the biggest impact of a project like this is developing human capacity.
Agrilinks: What makes chickpea such an important crop?
Cook: One of the defining features of legumes like chickpeas is their ability to fix nitrogen and imbue plants with higher levels of nitrogen in their seed, and they do so by interacting with specialized soil bacteria. Nitrogen fixation is not only linked to plant health and productivity but also human nutrition, as nitrogen is a major component of amino acids, the building blocks of proteins. In fact chickpea provides a primary source of nitrogen for about 20 percent of the world’s population.
So the lab has three activities built around this trait. One is to identify bacteria that are better fixers of nitrogen in chickpea. We are on the brink of making a commercial product if we can secure continued funding.
With co-funding from National Science Foundation, we also looked at whether cultivated species would be less efficient for nitrogen fixation and less selective about their bacterial partners than wild species, and we now know that’s the case. The differences between wild and cultivated species are dramatic, with significant differences in yield we can now approach by breeding. This is an important discovery that could change the way legumes are cultivated.
A third area of inquiry related to nitrogen in chickpea is its explicit nutrition content. We just started working with Nestle, the world’s largest food company. Protein is an important component of their processed foods, the main source of which is milk, which is costly in economic and environmental terms compared to plant based sources. So Nestle is looking at legumes to replace milk protein, and chickpea is a leading candidate. We are working with Nestle to look at the quality and quantity of protein in chickpea. They look at it from a practical view, focusing on attributes like taste and color, whereas we are interested in seeing if we can breed for better protein, and I think we can. This project is just beginning, but it wouldn’t have happened without USAID funding.
Agrilinks: What’s next for the project, as its funding through Feed the Future winds down?
Cook: We will continue pursuing these various lines of inquiry and are seeking follow-up funding. We know now that if we can successfully stack genes for resistance, for example, we can change chickpea globally. Now we need to partner with in-country institutions for fieldwork and testing. This is exactly what the US Global Food Security Strategy is about — harnessing the capacity of US-based labs to partner with developing country institutions to strengthen their capacity to solve these challenges.