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Ecology

Food with wings

Bees become more valuable for agricultural production

Fabio ColombiniA bee covered in cotton pollen: welcome reinforcementFabio Colombini

“I shall talk about bees and flowers,” announced the biologist Vera Lúcia Imperatriz Fonseca before an audience of economists and students of economics  at a debate held late in the morning of March 15 at the University of São Paulo (USP). This simple opening soon gained substance. In less than half an hour, bees ceased to be seen merely as producers of honey and acquired value as indispensible beings for maintaining or expanding agricultural production: crops such as soy, orange, cocoa, and coffee can become more productive when these insects are around. Biologists and economists started to realize, there and then, how they might cooperate to preserve the populations of insects such as bees, which aid the growth of fruit. Although these insects may not always be valued, they may be missed. In 2006, agricultural production in the USA dropped sharply when the Apis mellifera bees, used as agricultural pollinators, suddenly started to die off.

Researchers from USP and from other universities are joining up and working with other institutions to avoid similar consequences in the decline of natural pollinator populations. At the end of last year, CNPq, Brazil’s National Scientific and Technological Development Council, approved R$5 million for research to be conducted by groups from six states (Rio Grande do Sul, Bahia, Ceará, Minas, Pernambuco and Pará). The groups are to evaluate the impact of pollinators on the productivity of cotton, tomatoes, apples, melons, canola, cashew and chestnuts in Brazil. The Ministry of the Environment, which has been showing some interest in this field since the release of the São Paulo Declaration on the Conservation and Sustainable Use of Pollinators in 1999, started receiving international financing in the amount of R$7 million this year to implement a complementary project, called Pollinators of Brazil. “We need to show farmers exactly what they can do,” says Braulio Dias, the Ministry of the Environment biodiversity conservation director. “Our strategy is a win-win one, in economic and environmental terms.”

The people participating in this work want to learn as fast as possible how close Brazil is to a pollination crisis. “We haven’t reached one yet, but we’re moving in that direction,” says Vera Fonseca. It is even possible that a crisis has already materialized but has gone undetected, as there are several underlying causes at play: ongoing deforestation, the growth of cities and more severe climate change, which drive the migration of populations of bees and of other natural pollinators, such as butterflies, birds and bats. “The European Pollinators Initiative, which brought together 85 research institutions, detected that there was a crisis over there regarding pollinators and it has started to take action to reverse this as far as possible and to avoid the worst scenario.”

A team from the Federal University of Ceará (UFC), coordinated by Breno Freitas, is going to research the productivity of which crops could be stepped up by the intense use of pollinators. In one of his earlier experiments, Freitas showed that cashew tree production could rise by as much as 70% when bees flew freely among the trees, carrying pollen from one flower to the next and thus aiding the formation and growth of fruit, as compared to trees with no pollinators nearby. “The response will never be the same, because it depends on the local conditions,” says Freitas. “The more degraded the area, the greater the impact of the pollinators on agricultural production.”

Freitas found a lone stingless bee of the Centris genus that pollinates cashew tree flowers as efficiently as the Apis mellifera, the species most often used as a pollinator. As the Centris young feed off plants’ essential oils, Freitas is assessing the effects of planting acerola (which produces vegetable oils) to attract the Centris, so that these bees may pollinate the cashew trees nearby. “This might be a way of maintaining two crops in the same area, with one drawing pollinators to the other,” he says.

The coffee tree does not depend on natural pollinators, but the production of coffee plantations that are surrounded by woods with native bees has risen 15% relative to plantations in open areas, according to a Federal University of Viçosa study. “In Peru and in Costa Rica, production increased by as much as 50%, depending on the state and on the conservation of the native woods near the plantations,” says Vera. According to Freitas, in the case of beans, “even though the number of pods produced does not rise, better pollination by bees increases the number of beans per pod, which means a more profitable crop.”

EDUARDO CESARA touch of perfection: the quality of fruit such as these depends on pollinatorsEDUARDO CESAR

Proof at the market
There is no shortage of arguments in favor of pollinators. Tomato plants yield fruit more easily when bees visit their flowers and facilitate fruit growth. “Without natural pollinators, the farmer has to brush pollen onto each flower for the tomatoes to grow,” says Vera. A study by a group of biologists from USP in Ribeirão Preto showed that strawberries pollinated in hothouses by two species of stingless bees, the Scaptotrigona depilis and the Nannotrigona testaceicornis, yield more and better fruit than when they were grown in open areas with no bees. Vera tells us how she herself can see the pollinators’ impact on fruit sellers’ market stalls: “When I see an asymmetric or poorly formed apple or strawberry, I know that pollination wasn’t done properly.”

Açai berries, cupuassu fruit, passion fruit and aubergine also require bees, whereas papaya calls for moths in order to fructify. Globally, 70% of the 124 main crop consumed by humans (one third of global food production) depend on pollinators. Several international surveys indicate that worldwide disappearance of pollinating insects would be an environmental and economic disaster. The quest for more agricultural land might rise and native vegetation could become even scarcer. The estimated loss of fruit production would reach some R$130 billion and of cereals, R$100 billion. “It is high time to take pollinators more seriously,” says Vera.

Natural pollinators such as insects are still rarely used in Brazil. Only the apple farmers in the South and the melon farmers in the Northeast lease boxes with bee colonies to fertilize their plants. Forecasting that this state of affairs is about to change, Vera’s team at the USP Biosciences Institute in São Paulo worked with the USP team in Ribeirão Preto to raise in their laboratory queen bees of four different native stingless species that act as pollinators, including the jatai bee (Tetragonisca angustula).

“If necessary, we can produce one thousand queens a month,” says Vera. She feels that this is not much: “We have to prepare for commercial production and for substantial demand in the near future.” Astrid Kleinert and Kátia Malagodi-Braga, from her team, showed in 2004 that strawberry production could be greater with the aid of the jatai bees. “The method paid off, but the producers still can’t order one thousand jatai colonies from anybody. Since 2006, the world trade in pollinators has produced more than one million colonies of Bombus terrestris a year. Here in Brazil this might also be a good line of business, as each box of jataí colonies costs about R$100.”

Difficult choice
The production of native species of queen bees in rising numbers may help to multiply the nests of native bees and to reduce dependence on the Apis mellifera, the sole pollinating species produced on a broad scale worldwide. Apis is versatile and resistant to temperature changes, but it does not suit all crops. For tomato plants, a stingless species, the Melipona quadrifasciata, turned out to be more efficient than the Apis mellifera, inducing the formation of larger fruit in greater number, according to a study conducted by the group of Luci Bego at USP in Ribeirão Preto. Vera Fonseca informs us that she has been getting calls or messages from tomato farmers asking what bees they can release in their plantations to get more tomatoes, but she still has no single, simple answer. “We have certain possibilities and we’re comparing data to see if we can recommend what species to use,” she says.

The shortage of immediate answers is not due to a lack of research. The production of knowledge is significant and is coming from consolidated groups, established decades ago by pioneers such as Paulo Nogueira Neto and Warwick Kerr in São Paulo, and by Jesus Santiago Moure in Curitiba. There is a different reason. “We have a lot of native bee species and most of them are not yet very well known,” says Antonio Mauro Saraiva, a professor at USP’s Polytechnic School who has been working with Vera Fonseca since 1999.

Brazil is home to some three thousand bee species with social or solitary habits. Some are rare, such as the Melipona bicolor schencki. Biologists are yet to discover what plant this bee uses to produce its white honey, “with an incredible flavor,” according to Vera. However, this is already one of the four stingless bee species from Rio Grande do Sul that may disappear if the aracauria forests vanish.

An electrical engineering and agronomy graduate, Saraiva is in charge of the technological support for the research into pollinators. Along with his team, he produces the data collection equipment and computer programs that allow access to biological collections in Brazil or abroad. “What we do for one group may be useful for another one,” he says. This is the case of the beehive monitor, a device with sensors that monitors moisture and temperature and that is to be tested this year in an apiary in Mossoró, state of Rio Grande do Norte. Perhaps the device will be able to forecast the risk of the bees abandoning their beehives due to too high a temperature.

Pest-free orchards
Articles on pollinators are becoming increasingly common in one of the main apiculture magazines, Mensagem Doce, published by Apacame, the São Paulo Association of Apiculturists of European Melliferous Bees. Currently convening 7,340 apiculturists, the association adopted in 1981 the slogan “bees at the service of agriculture” to expand the use of bees beyond honey production. According to Constantino Zara Filho, the chairman of Apacame, the pursuit of Apis as an agricultural pollinator has progressed continuously in Brazil. “Anyone who wants to produce more or harvest uniform, well-formed fruit must rely on natural pollinators,” he states, adding that bees can also further orchard health by consuming the nectar and pollen that might attract insects which damage the plantations.

The conclusions on the value of crop pollinators and native forests are gaining visibility, but in Brazil there still is nothing similar to the Pollinator Partnership, an NGO in the United States that is a source of information and action regarding pollinators and that also awards governors and farmers that protect pollinators. The national pollinator protection campaign conducted by Pollinator Partnership has brought together 120 institutions, researchers, conservationists, government representatives, students and professors. “We’re trying to mobilize the NGOs to join this project and help disseminate these ideas,” comments Dias.

What the pollinators do for crops is just one of the services of ecosystems, an expression designating the services rendered by nature, such as supplying water and the control of erosion, floods and pests, besides leisure, in the form of pleasant beaches and mountains. This concept was strengthened by an article in the journal Nature in 1997, which estimated that the services of the Earth’s ecosystems were worth some R$33 trillion. In 2005, it yielded the study “Systemic evaluation of the millennium,” organized by the United Nations. “China has adopted payment for ecosystem services,” says Vera. “They found that this would be cheaper than paying for damage to the environment.”

Acknowledging the value of pollinators and the environmental services that they provide depends on overcoming old approaches. “In the curriculum of the agronomy course,” states Saraiva, “there are no disciplines on pollination.” New proposals do not always spread fast. Vera Fonseca believes that people, even those who are not farmers or apiculturists, can keep colonies of jatai bees in squares, streets, apartments and schools, and not only in country properties and plantations, allowing these versatile and harmless bees to pollinate nearby plants as much as possible. However, she is aware that this notion still sounds rather exotic.

The Pollinator Partnership, an NGO from the United States, awards governors and farmers who protect pollinators.

The project
Biodiversity and the sustainable use of pollinators, with emphasis on Meliponini bees (nº 04/15801-0); Type Theme project – Biota-FAPESP Program; Coordinator Vera Lúcia Imperatriz-Fonseca – IB/USP; Investment R$ 3,036,892.21 (FAPESP)

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