This blog post was written by David Guerena, Agricultural Innovations Manager at One Acre Fund.
Pulse crops are critically important to human nutrition, soil health, and agricultural productivity. These edible seeds of the legume family of plants are one of the main dietary staples for approximately 2 billion of the world’s poor, many of whom live in remote areas and depend on agriculture for their livelihoods. The symbiotic partnership between legumes and soil bacteria, which imparts the ability of legumes to biologically fix nitrogen from nitrogen gas in the air, is critical to combating poverty, environmental degradation, and improving soil health.
The first great civilizations all knew about the importance of legumes. In the millions of years before the invention of the Haber-Bosch process in the early 20th century, most of the earth’s biologically available nitrogen came from legumes. The inhabitants of the Fertile Crescent (modern day Israel, Turkey, Syria, and Iraq) cultivated peas, lentils, and chickpeas along with wheat. Inhabitants of the ancient Americas (modern day Mexico and the United States) cultivated beans with maize, while the ancient Chinese cultivated soybean and rice. Today, we know that soybeans contain almost twice the amount of protein and seven times more calcium than rice. Similar differences are apparent between most legumes and other staple grains. Legumes are also a critical source of folic acid, a necessary nutrient for prenatal and early childhood health. Several studies estimate that grain legumes may be a potent tool to fight childhood stunting (Tharanathan and Mahadevamma, 2003; Bevis, 2015; Smith and Hadad, 2014).
Despite their proven importance, aggregate investment in legume breeding and cropping systems research is estimated to be only one quarter of the investment in maize. Additionally, within aggregate legume investment, the majority (60 percent) is dedicated to soybean, while the multitude of other legume species (e.g. common beans, pigeon peas, fava beans, cowpeas) get the remaining 40 percent. Over the years, systematically low investment has resulted in yields that fall far short of the yield potential for these alternative legume species, despite their low requirement for fertilizer.
The phenomenon of low yields has dire consequences for smallholder farming communities where many alternative legume species are commonly grown. For example, common beans, grown in the humid highland systems of eastern and central Africa, routinely yield below 1 metric tonne per hectare (t/ha), yet the yield potential is above 2 t/ha for bush cultivars and above 4 t/ha for climbing cultivars. Pigeon peas, common to the dry lowlands of eastern and southern Africa, often yield below 500 kg/ha, despite yield potentials well above 1 t/ha. In many cases, pests, disease, and incorrect planting, spacing, and weeding techniques are some of the main yield limitations.
While aggregate farmer legume yields are low, the methods for achieving high yields are known: utilization of improved genetic resources (better varieties) and good agronomic practices (fertilizers, spacing, weeding, etc.). Improved varieties that are resistant to pests and diseases can also be a first line to close the yield gap.
In many cases, where improved varieties exist they often have other characteristics (e.g. seed color, cooking time) that are not in sync with local preferences. Introducing black-seeded beans in an area with strong preferences for green or a pigeon pea variety that requires 6 hours of cooking in areas with only 4 hours of available cooking fuel will limit adoption. In addition, most legumes are grown in intricate intercropping systems. There is often contradictory information on the most efficient recommended intercropping agronomic practices.
While part of the challenge lays in re-focusing research efforts, getting that research into the hands of farmers is another part of the challenge. One Acre Fund, a direct-service agricultural nonprofit I work with, has partnered with several of these organizations to deliver valuable research findings to hundreds of thousands of smallholder farmers in eastern and southern Africa. These interventions are still being evaluated and contextualized to local demands and preferences, but initial results are promising. In Rwanda, we have used the microbial soil inoculants developed by N2Africa to maintain high soybean yields, while reducing the fertilizer input by 50 percent. In both Rwanda and Kenya, we have worked with the TL-III program and plant breeders from the national agricultural research system to bring improved bean seeds to tens of thousands of farmers. The Rwandan bean seeds are naturally fortified with high levels of iron, a critical nutrient for human nutrition. In Kenya, the bean variety was developed locally to be highly resistant to root diseases.
These innovations are examples of the existing potential to bring legumes out of obscurity and to the forefront of the fight against poverty and malnutrition. The world’s population is projected to reach 9.6 billion by 2050, with more than half the growth in Africa. To meet increased food demands, it is essential that we bolster the productivity, resilience, and nutrition of smallholder farming communities. As the United Nations celebrates the International Year of Pulses in 2016, the timing has never been better for the development community to invest in legumes. Our collective global future depends on it.
One Acre Fund staff live and work alongside the farmers we serve, helping them improve their harvests and grow their way out of hunger and poverty. Learn more about One Acre Fund’s work today.
This blogpost was originally published on the Achieving agriculture-led food security through knowledge sharing (Agrilinks) for more information click here.