Living in harmony with insects
Agriculture and insects are important elements for the fast-growing world population. Scientists strive to use sustainable approaches to obtain more abundant yields and pursue many lines of investigation to control dangerous pests. At the International Center for Insect Physiology and Ecology (icipe) in Nairobi, Kenya, director general Segenet Kelemu drives cutting-edge research to support beneficial insects, control those that cause problems, and even to identify insects that could be used as a source of protein for the world's population.
Kelemu, an influential scholar and the first woman to lead icipe, recently attended Trieste Next 2015 (25-27 September), the annual European fair of scientific research in Trieste, Italy. She was a dynamic presence on a roundtable organized by TWAS.
At Trieste Next, she explained how she is pursuing other lines of investigation. She is promoting an environmentally friendly technique called push-pull, to manage crops without using chemicals. This technique also eases women's work as it spares them from bending over crops to pull weed and save the yield.
Kelemu was the 2014 L’Oréal-UNESCO for Women in Science Awards Laureate for Africa and the Arab States, after being elected a fellow of the African Academy of Sciences in 2013. She won the 2011 TWAS Prize for Agricultural Sciences.
In an interview with TWAS staff writer Cristina Serra, Kelemu discussed the role of biotechnology and innovation, explaining why insects are so important not only for agriculture but as a potentially abundant and inexpensive source of food.
The research at icipe is mainly focused on insects and the effects they exert on crops and environment – why?
Insects are everywhere, by far perhaps the most common organisms on our planet. Without insects, our lives would be significantly different. However, insects pose major challenges to the well-being of people, livestock, crops and the general environment, both in Africa and globally. Insects damage food, often causing the loss of entire crops and destroying significant amounts of harvested food in storage. They also transmit a myriad of diseases, like tsetse flies. Mosquitoes alone kill more people globally than all other conflicts combined together.
Are all insects noxious?
Not at all. Some insects and arthropods also play significant beneficial roles thanks to their rich biodiversity, including a range of valuable ecosystem services. They degrade organic matter. Insects are either primary or secondary decomposers making our planet cleaner. They play a major role in the food web as food and feed sources for a wide range of animals and humans. They are an interesting part of our landscape and nature – butterflies, for example. They control pests and diseases, and they pollinate many of our fruits, flowers, vegetables and other plants. Insects also provide us with food, feed, textiles, waxes and numerous other products. If we have to address the health of our environment – and the humans, animals and plants that require a healthy environment – then we need to comprehensively address issues related to insects and related arthropods.
Biotechnology and sustainable agriculture are viewed as conflicting approaches, especially in many European countries. What is your view – are they compatible, or not?
They are not in contradiction. First, we need to understand what “sustainable” means. To me, sustainable means the use of less resources to produce more food for the growing population on our planet. There are limited resources for agricultural production – limited land, water resources, agricultural inputs, and so forth. The resources we have on our planet are not infinite and therefore we have to be innovative in the effective and efficient use of these resources. Improved, high-yielding crop varieties allow us, for example, to produce more on limited land. Crop varieties can be created with increased water-use and nutrient efficiencies. Varieties with pest and disease resistance allow us to use little or no pesticide. Therefore, farming with biotech crops and organisms is sustainable.
Is biotechnology applied to agriculture a tool we should use to help fight hunger, especially in Africa and developing countries?
The word biotechnology refers to a gradient of technologies, ranging from the long-established and widely used techniques of traditional biotechnology to novel and continuously evolving modern biotechnology. Africa’s needs are not different from the needs of any other continent on the planet: high-quality and sufficient foods for all its people; access to sufficient and clean water; access to high quality health care and generally high standards of living. To do this, Africa needs various technologies including bioscience technologies; improved irrigation and other infrastructure systems; progressive policies that address issues like access to land and land tenure; enhanced human capacities in various areas. Ultimately, it's essential for Africa to utilize its vast natural resources properly and equitably so that it benefits its all of its people. And in the process, it is important to close the existing gender gap.
Can biotechnology help humanity to address climate change?
Yes. A number of bioscience innovations can help breed crops that adapt to climate change, such as crop varieties that are drought-tolerant, and animals that are more tolerant of heat stress. Biotech crops in general need less field operation, for example; low-tillage crops, which permit more crop residue to remain in the soil, sequestering more CO2 in the soil and reducing greenhouse gas emissions.
As the director of icipe, you are promoting a sustainable innovative technology called push-pull. What is it about?
Push-pull technology is a simple cropping strategy that uses natural biological processes to control Striga weeds and stemborers. Push-pull involves using insect-repellent plants like Desmodium (the push), and insect trap plants like Napier grass or Brachiara grass (the pull), which are planted between rows (the push plants) and as borders around farm plots (the pull varieties) respectively. The repellent crops planted inside the field emit volatile organic compounds that are repugnant to the stemborer moths but are attractive to their natural enemies, like parasitic wasps. Stemborers are repelled from the main crop and lay their eggs on trap plants, which are planted around the field. Here, the trap plants do not allow development of larvae to adulthood.
How is Striga weed controlled with this technology?
Root exudates released by Desmodium contain several biologically active compounds that both stimulate germination of Striga seeds and inhibit Striga roots development. In this way, they prevent Striga from attaching to the host plant roots. In other words, the combination of these compounds provides an efficient way of causing suicidal germination of Striga seeds resulting in depletion of the seed bank in the soil. In addition, both the repellent and trap plants provide high-quality animal feed.
Why is push-pull technology also a user-friendly technology, especially for women?
African women farmers spend substantial amounts of time hand-weeding and collecting animal feed, among other tasks. Push-pull technology is women-friendly because it reduces the need for some heavy physical labor, which is typically carried out by women. As a result, about 60% of the farmers who have adopted it are women. These women do not have to weed by hand anymore. They do not have to travel long distances to collect poor-quality animal feed any longer. This is empowerment of women, clear and simple.
We are witnessing a dramatic and rapid increase in the world population, which today is 7.2 billion. According to UN estimates, we may reach 9.6 billion by 2050. Insects are already part of local diets in many countries (there are at least 1900 species of edible insects). What are the chances to use insects as regular future food?
This happens already: Globally, it is believed that about 2 billion people, mainly in the developing world, consume 2,000 species of insects. Although mainly recognized as pests or a nuisance affecting human, plant and animal health, insects play essential role in minimizing food insecurity in addition to providing ecosystem services such as pollination, waste degradation and biological control. This has become especially important as the need for alternative protein sources increases due to rapid urbanization in developing countries and the shifts in the composition of global food demand. As a centre of excellence in insect science and its application, icipe is obliged to respond to the opportunity of promoting insects as food and feed to add value to the global call by the UN Food and Agriculture Organization and others to utilize insects to improve food and feed security and contribute to the livelihood of people and protection of biodiversity and ecosystems. The centre has responded to this call by establishing the "Insects for Food, Feed and Other Uses" programme. By doing this, we not only will contribute to improving food and nutritional security, we will be also alleviating the burden of hard labour on women and children.
It seems that icipe's activities, as well as its focus on insects and sustainable agriculture, are future-oriented, and keep an eye on the most vulnerable classes.
This is true. With the expanding agribusiness companies in the field of insects for food, feed and waste conversion in Africa, insects clearly have a role to play in significantly contributing to eradication of hunger, malnutrition and food insecurity in the UN’s post-2015 development agenda. Women and children play active roles in the edible insect sector, mainly in the collection, processing and sales, and all of these endeavours are important parts of many families’ livelihood strategies.