Chickpea Wild Relatives: Using Science to Change the World

Whenever I mention working with chickpeas, the almost universal response I get is “Oh yeah, hummus!” What most people don’t realize is that chickpea provides primary protein to over 1 billion people globally, with India (1.2 billion), Pakistan (180 million), and Ethiopia (95 million) among the biggest consumers.

What’s more, due to its capacity to fix nitrogen from the air, chickpea enriches our soils. This is especially important for the developing world, where a large percentage of the population is plagued by malnutrition, and thousands of subsistence farmers work in marginal soils. I cannot think of a better crop than chickpea to address these combined challenges. Chickpea is in fact the world’s third ranking food legume in production (acreage and yield), and one of the most important crops for food security.

Along with most modern crops as we know them, the chickpea is the result of human ingenuity. From domestication approximately 10,000 years ago in the Fertile Crescent to intensive selection and targeted breeding since then, farmers and plant breeders have developed modern varieties that are adapted to local conditions and are resistant to many pests and diseases. Central to this process has been the development of varieties that exhibit a combination of desired traits, such as early flowering and high yield. What is easy to forget, however, is that we have inadvertently lost genetic variation along the way.

This loss of diversity constrains plant breeders’ efforts to adapt the crop to new challenges (i.e. harsher climates), handicapping farmers and posing a threat to future food security.

But the genetic diversity that has been lost in the process of domesticating the chickpea may still be out there. The wild relatives of the crop are a potential source of genetic diversity that can be explored and used to improve modern cultivars. Crop wild relatives are the wild ‘cousins’ of our cultivated crops and often contain genetic traits not present in domesticated species. Through mating wild relatives with the crop species to which they are related, plant breeders are available to develop new varieties that address modern agricultural challenges.

That is exactly what we are doing here at the Chickpea Innovation Lab, UC Davis, with support from many partners around the world, including the Crop Wild Relatives Project, which is co-managed by the Crop Trust and the Millennium Seedbank at Kew. Our chickpea pre-breeding work is one of 19 projects in which scientists in more than 44 institutions and 27 countries are working to introduce the “toughness” traits of the wild relatives into our more pampered domesticated crops.

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My career path has been intimately influenced by my early life experiences. I was born in Keroka, Kenya and grew up in a farming community that struggled every year to produce enough food to feed itself. My immediate and extended families are largely made of subsistence farmers, so I was exposed to the woes of impoverished farming communities at an early age.

I was deeply saddened by the hungry babies I saw both in my neighborhood and on the news, as year in and year out dry spells turned into famines. What was striking to me was how these images were consistently from Africa, and ever since I have wanted to change this.

My dream is to use science to change the world. This vision fueled my decision to study Science in Biotechnology at Kenyatta University in Kenya, then pursue a Master’s degree in Plant Biotechnology from Wageningen University in The Netherlands, and is why I am currently working on my Ph.D. in Plant Biology at the University of California, Davis.

It is here at UC Davis, working in Dr. Doug Cook’s Chickpea Innovation Lab that I am helping to solve the greatest challenges in chickpea production. As a whole, the Chickpea Innovation Lab aims to develop chickpea lines from selective crosses of modern elites with wild relatives, combining the very best of traits from each side, aimed at addressing specific issues in targeted agricultural regions.

Our work is carried out by using modern molecular biology tools, mathematical modeling, as well as advanced phenotyping platforms. The process can take years, beginning from screening for desired traits – which can include drought and disease tolerance, nitrogen fixation, high yield and high nutrient density — to finally having these traits in varieties that breeders and farmers use. However, technology and collaboration with other laboratories will increasingly speed up the process

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The work I do as part of the Crop Wild Relative project is focused on drought, the single biggest challenge in chickpea production.

Drought imposes the largest penalty on food crops, leading up to over 50% losses in yield. Large areas in Sub-Saharan Africa and South Asia grow chickpea under drought conditions, e.g. Ethiopia, Pakistan, and India. With climate change threatening to exacerbate the severity and impact of drought on agricultural production in general, it is especially timely to see what can be done about making chickpea more resilient to lack of water.

My research is therefore specifically focused on finding out whether or not wild chickpeas perform better in drought than modern cultivars.

To answer this research question, I am first describing the physical responses of wild chickpeas in both simulated and actual field experiments. I will then go on to find the genes responsible for any positive traits observed.

My work complements what my colleagues are doing in the Innovation Lab. Together, we are surveying the performance of wild chickpeas on multiple levels, looking at resilience to environmental stresses and diseases, nutrient uptake and utilization, as well as associated beneficial microbes. These are all agronomically important traits that could be useful to subsequent breeding efforts.

We are only beginning to understand wild chickpeas. As such, there are many aspects of our work that are difficult to plan for, given that certain characteristics of the wild relatives remain completely unknown.

As happens in all scientific endeavors, a lot of time and effort must be invested into getting things wrong, so we can eventually get them right. I, for example, set up a field experiment a few weeks ago, planning on taking advantage of the dry summers in Davis to characterize responses to low soil moisture. Unfortunately, one week of very high temperatures (not uncommon in this region) completely stressed out the little seedlings that were only beginning to set, and we lost all the material and had to set up the experiment in a more controlled environment instead. Back to square one.

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I was fortunate enough to join the Chickpea Innovation Lab in its infancy, which has allowed me to actively participate in nearly every aspect of its work – from curating material that had been collected in the crops’ native regions in Turkey, to growing the wild seeds in glasshouses for multiplication of the various populations, to carrying out the morphological characterization of the populations.

I thank the Crop Wild Relatives project, the Crop Trust and the Norwegian Government for supporting my research. I also thank Dr. Cook for his guidance and support.

My participation in such a big project with wide collaboration has also increased my networks abroad, in countries like Ethiopia, Australia and Canada, and even back home. Building relationships with people all over the world will be forever useful. Moreover, the work we carry out exposes me to a wide range of skills, including plant physiology, transmission genetics, molecular biology and plant breeding. I am learning and improving my technical skills in all of these areas. Additionally, through teaching opportunities, I am acquiring didactic skills and better mentorship proficiencies.

I am happy and proud to be part of a project that will help the lives of so may across the globe. The outcome of my research will have a direct impact on the choice of varieties selected by chickpea farmers everywhere. And in the process, I continue to acquire the knowledge needed, and develop the skills necessary, to design and conduct crop research projects that are relevant to communities at home, elsewhere in Africa and beyond.