Africa ‘needs green revolution’

Sub-Saharan Africa’s agricultural sector needs to harvest the fruits of biotechnology in order to establish sustainable development, says a report.

A key challenge is to attract funding for biotechnology projects on staple crops, such as cassava, it added.

Farmer digs a whole in a cassava field (Getty Images)

These crops were often ignored by commercial funders because they had a limited market, the authors suggested.

Africa missed out on the previous green revolution that boosted food output in many Asian and Latin American nations.

The report, On Trial: GM Crops in Africa, published by think tank Chatham House, said: “Increasing agricultural productivity and adapting farming to climate change are central to Africa’s development prospects.”

It added that there were opportunities to boost yields and increase resilience by improving existing crop varieties, and that “in some cases, biotechnology, and in particular genetic modification (GM), offers advantages over conventional plant-breeding approaches”, such as drought, pest and disease resistance.

However, the continent was in danger of missing out on capitalising on innovations offered by the 21st Century green revolution, just as it had done in the previous century.

“If you look at what happened in Latin America and Asia in the second half of the 20th Century with the Green Revolution, there was a range of technologies, new high-yielding hybrid varieties of wheat, rice and maize, new irrigation platforms, etc,” explained co-author Rob Bailey, research director for energy, environment and resources at Chatham House.

‘Growth spurt’

He added that this acted as a “growth spurt for development” because it delivered a big increase in yields and agricultural productivity allowing food prices to fall, increased food security and a diversification in economic activity in other sectors.

Vegetable stall, India (Image: BBC)
Crops that do not have a global market do not attract the same level of private sector R&D investment

“Now, we are in a situation where Africa needs this growth spark in its agricultural sector, because it is primarily where most of the poorest people are, and it makes up a significant share of African GDP,” Mr Bailey said.

“But they are also in a race against time because climate change is gathering pace because the forecasts suggests that this is going to have a very profound impact on farm productivity.”

He explained that the need to increase resilience to forecasts of a changing climate was likely to increase the importance and need for innovation and R&D offered by biotechnology projects.

“The key challenge that African agriculture faces is that a lot of food security and livelihoods are dependent on these so-called orphan crops, such as cassava and sorghum, which do not have large commercial markets in the way that maize or wheat do. Therefore they are not attractive to large private sector researchers,” he told BBC News.

“So the first thing that Africa has to do is attract and mobilise public sector money to fund research into these sorts of technologies.”

Mr Bailey explained that biotechnology offered a range of advantages over traditional breeding methods: “A lot of the staple crops that are grown in Africa have quite narrow gene pools. There are not huge seed banks, with lots of different varieties of cassava or sorghum, that can be tapped into. It is not like maize or wheat.

“Biotechnology can be useful there because it provides plant-breeders with the opportunity to introduce genes or traits from outside of the species’ genomes.

“If you can identify a trait for pest resistance in another species and cannot find a trait like that within the cassava genome, then a conventional plant breeder is a bit [stuck].

“If you are using transgenics then you have the opportunity to bring that trait in from another species.”

Growing support

But he added that this was easier said than done because many sub-Saharan governments had limited resources and scientific capacity, and there was a danger of simply adopting models developed for Western food crops.

Mr Bailey said: “The problem with these sorts of models is that they do not properly engage the farmers.

“They have to be careful to make sure they are working with farmers from the outset so then they can understand what are the farmers’ needs, how they can be addressed and included in the technological process so they are more likely to use and adopt it when it is ready.

“A key message from the report is that you need to start with the farmers, understand their context and their market environments. This is the platform you use to judge whether or not you can develop a technology-based solution.

“If you come in and try to parachute something in from elsewhere because it has worked in Europe or North America then the risk of that technology failing or not being used are much higher.”

New approaches are needed for another Green Revolution.

Twenty-first century agriculture needs low-input advances like the System of Rice Intensification, says Norman Uphoff.
According to the principle of diminishing returns, continuing to producesomething in the same way, with the same inputs and technology, usually becomes less productive over time. This appears to apply to agriculture‘s ‘Green Revolution, as yield improvement has slowed in recent decades, no longer lowering the real price of basic foods as it did in its first three decades. Diminishing returns may not be a universal principle — but agronomists should take it seriously.

Although there is talk of another Green Revolution, the approaches beingproposed are essentially more of the same. This technological strategy for raising production is running into major economic and environmentalconstraints, however. The costs of fossil fuel-derived inputs keep rising, while impaired soil health and degraded water quality are growing concerns. 

Paradigm shift
Fortunately, there are agroecological options available, such as conservation agriculture and the System of Rice Intensification (SRI), which differ fromhigh-tech and input-dependent production systems. 

Agroecological management systems capitalise on the potential for more productive and robust crops from existing plant genomes and on their intricate, symbiotic associations with other organisms, particularly microorganisms — in what is now becoming better understood as the plant-soil microbiome. [1]

A paradigm shift  from regarding non-crop organisms as mostly pests or pathogens and treating plants as carbon-based machines, to understanding networks and webs of symbiotic relationships  can help us ‘rebiologise‘ agriculture and adopt alternative methods that are better suited to current and foreseeable challenges.

More for less
By changing how plants, soil, water and nutrients are managed, SRI practices grow larger, betterfunctioning root systems that interact with a bigger and more diverse soil biota, also promoted by these same practices. 

Compared with standard crop management methods, SRI practices raise yields usually by 50100 per cent and sometimes more. These gains are achieved with less water, greatly reduced seed rates, less or no inorganic fertilisers, and often even with less labour once the methods have been mastered. [2,3,4,5]

Other benefits include greater resistance to drought and water stress, storm damage, and to pests and diseases  pressures on crop production that willcertainly increase with climate change. 

Record yields
In 2011, a farmer in the Bihar state of India who had adopted SRI reportedlysurpassed the world-record paddy yield previously set in China. This stirred controversy — but having analysed how this yield of 22.4 tonnes per hectarewas achieved and measured, with data from the Indian government’s Directorate of Rice Development, I am satisfied that the farmer achieved this yield. [6

Agriculture in the twenty-first century will need to change considerably from the technologies and paradigms that evolved in the preceding century.

Norman Uphoff, Cornell University

This record yield is less significant, however, than two other statistics. First, the rice area under SRI methods in Bihar has risen from 30 hectares in 2007 to more than 300,000 in 2012, a 10,000-fold increase in five years. Second, even without all of the farmers following SRI recommendations fully, their average SRI yield in 2012 was calculated by government technicians as 8.08tonnes per hectare — three times the usual yield in Bihar. 

These figures and differences are so large that SRI can no longer be ignored by sceptics and critics. They come from farmers’ fields and from officialreports, not from experimental stations and partisan sources.

Winning the argument
Published criticisms of SRI have ebbed since 2006, with the benefits from SRInow demonstrated in more than 50 countries. But initial opinions die hard,even as governments in Cambodia, China, India, Indonesia and Vietnam, where two-thirds of the world’s rice is produced, have begun supporting the spread of SRI, based on farmers’ experiences and scientific evidence.

It is time to put the ‘controversy’ over SRI behind us. And it is time to begin learning more about how these new ideas and methods can help get more from less. 

For instance, we have begun to learn how microorganisms that livemutualistically within plant organs and tissues, and even cells, bring benefitssuch as increasing the chlorophyll levels in leaves and protecting against pathogens in roots. [7,8]

Learning from farmers
Importantly, experience with SRI in countries such as Burundi, Cuba, India,Madagascar, Nepal and Rwanda is helping us to better understand how to learn from and with farmers. Some very informative and impressive videos are now available where farmers themselves explain their good experienceswith these new methods. [9]

Farmers have been adapting and improving the methods to which they were introduced, and they have been disseminating their knowledge and experience to other farmers — changing the usual linear ‘from lab to land’model of developing and transmitting innovations.

SRI is one of the few innovations where scientists have had difficulty replicating farmers’ results in their on-station trials  usually the situation is reversed. Farmers may be getting higher yields than the researchers dobecause, more often than not, farmers’ soils have less impairment fromfertiliser and agrochemical applications than on experiment plots. 

Changing times need changing practices
Agriculture in the twenty-first century will need to change considerably from the technologies and paradigms that evolved in the preceding century.Conditions are becoming increasingly different from the past. The need to change should not be taken as derogation of past research and practices. 
Both scientists and farmers need to evaluate alternative methods that could be more suited to our new realities. Proponents of agroecological alternatives welcome systematic evaluation that is conducted rigorously, with open minds and with farmers’ participation. 

Norman Uphoff is professor of government and international agriculture at Cornell University, United States, and senior advisor to the SRI-Rice Centerthere. For 15 years he has been trying to get SRI principles and practices better known, evaluated and taken up where beneficial for farmers, consumers and the environment. You can contact him at

This article is part of the Spotlight on Producing food sustainably.



[1] Nature  doi: 10.1038/501S18a (2013)
[2SRI International Network and Resources Center (SRI-Rice) website
[3] Sato, S. and Uphoff, N. Raising factor productivity in irrigated rice production: Opportunities with the System of Rice Intensification. CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources (Commonwealth Agricultural Bureau International, UK2007)
[4] Experimental Agriculture doi10.1017/S0014479707005340 (2007)
[5] Agriculture and Food Security doi: 10.1186/2048-7010-1-18 (2012)
[6] Diwakar, M.C. et al. Report on the world record SRI yield in kharif season 2011 in Nalanda district, Bihar state, India (Agriculture Today, New Delhi,July 2012)
[7] Applied and Environmental Microbiology doi: 10.1128/AEM.71.11.7271-7278.2005 (2005)
[8] Proteomics doi: 10.1002/pmic.200900694 (2010)
[9] Farmers from Burundi, Cuba, India, Madagascar, Nepal and Rwanda speak for themselves in videos about their experiences with SRI: Flooded Cellar Productions,