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agronomy

Valuable enemies

Company from Piracicaba produces and exports insects to fight farms pests

Installed in a residential district of the city of Piracicaba, a company created just two years ago, Bug Agentes Biológicos, is braving a routine of intense production to meet the growing demand for insects that are natural enemies of farm pests. Working in small groups in climatized rooms, 30 members of staff, most of them women, are taking care of the insects’ diets, choosing the most vigorous, and, in several manual stages, preparing natural enemies of eggs and caterpillars used to control pests that attack sugarcane, tomatoes, corn and other crops. At the end of the process, a good part of the production is shipped to Switzerland, France, Denmark and the United States.

“There are similar laboratories in several parts of the world, using eggs to create, produce and multiply theTrichogramma wasp, which is responsible for fighting several species of moths”, reports Josê Roberto Postali Parra, a director of the Luiz de Queiroz College of Agriculture (Esalq), of the University of São Paulo. A consultant for Bug’s project for breeding and marketing insects to control farm pests, financed by FAPESP under the Small Business Innovation Research Program (PIPE), Parra is a professor at the Entomology, Phytopathology and Agricultural Zoology Department.

Presently, about 30% of the monthly production of 10 kilos of eggs of the Anagasta kuehniella moth, used by the Trichogramma wasp for its reproduction, is sent abroad. This volume is sufficient for the formation of 360 million predators of insects that are harmful for agriculture.

Economic gain
The interest of these customers in what is produced by Bug, which has as its partners agronomist engineers Danilo Scacalossi Pedrazzoli and Diogo Rodrigues Carvalho, students for a master’s degree at Esalq, can also be measured by the growing number of hits at the company’s website. “Visits made from countries like the United States, France, Denmark, Switzerland, Italy, Holland, Spain and Portugal, by laboratories that are already customers or are looking for our products, account today for 70% of the visits”,according to Danilo’s calculations. In Parra’s assessment, biological control is today an accepted way for halting the action of pests, in answer to the inadequate use of insecticides, harmful to human and animal health and to the environment.

The economic factor is also taken into account when this system is adopted. In the case of the sugarcane borer ( Diatraea saccharalis ), for example, a pest that causes losses for sugarcane growing and the industrial production process, biological control costs R$ 15.00 per hectare, including the parasites, freight and application, while the chemical treatment works out at R$ 45.00 on average. In the field, this pest causes the plant to lose weight, by virtue of the opening up of channels in the culm (stem) of the cane and failures in germination, among other damage.

In the industrial process, due to the red rot, caused by the borer in association with fungi, chemical changes occur, such as transformations in the sucrose, a reduction in the purity of the juice, and contamination of the process of alcoholic fermentation, factors that lead to a lower yield of sugar and alcohol.Studies have shown that each 1% in the intensity of infection by this pest in a plantation corresponds to a 0.25% loss of sugar, an amount that can be altered according to the variety of the plant used. “This means a loss of 212 kilos of sugar in a property that produces 85 tones of sugarcane”, reckons Alexandre de Sene Pinto, a professor at the Moura Lacerda University Center in Ribeirão Preto who is coordinating the project. “If the borer reaches an intensity of infestation of 10%, which is not difficult, there will be 2,125 kilos lost.” In the production of alcohol, for each 1% of intensity of infestation, a loss of 0.20% occurs.

Special diet
The biological control of the borer is done with a small imported wasp, Cotesia flavipes , which is a parasite of the pest in the caterpillar stage. Both the insect pest and the parasitoid (an animal that feeds on, and frequently kills, the host) are produced in Bug’s laboratories. “The creation of natural enemies has been done in Brazil for some time by the sugar mills, but the novelty of our project is the perfecting of the breeding technique, with innovative technology”, says Parra.

In its adult form, the borer is a moth of nocturnal habits, of a straw yellow color. The females lay their eggs on the leaves. The caterpillars, after some time, penetrate the sugarcane, where they take shelter and feed themselves. The production of this caterpillar at Bug begins with a special diet, with proteins, vitamins, mineral salts, carbohydrates and lipids, deposited in a gelatinous medium (agar). The diet is put into tubes or flasks, developed by the researchers to serve as food for the caterpillar. The best specimens of this larval form are separated and offered to their natural enemy, the little Cotesia , which measures about 2 millimeters.

After this phase, the caterpillars, full of wasp eggs, are taken to a room with a controlled temperature. “The evolutionary mechanism has prepared the parasitoid not to kill the caterpillar quickly. This only happens when the wasp completes its development cycle”, Parra explains. The Cotesia cocoons, resembling a white paste, are then separated in order to be sold. Bug’s monthly production of 40 million natural enemies of the borer is sufficient for the biological control of 6,600 hectares of sugarcane. Considering that some 5 million hectares of cane are planted inBrazil, the potential for the usage of this natural enemy is very great.

“In the areas where Cotesia does not adapt to the climate, chiefly Mato Grosso and Goiás, we recommend Trichogramma , a parasitoid of the eggs of several farm pests, affecting cotton, sugarcane, soybeans, tomatoes and cabbages”, the consultant says. It has as its great advantage the fact that it can be bred in eggs of alternative hosts, such asAnagasta kuehniella , a moth found in warehoused cereals. The moth’s diet is very simple, just whole-wheat flour and yeast, which means a saving in the production process. The food and the moth’s eggs are put on top of cardboard.

In a short time, this cardboard is transformed into a nest in which the moth completes its development and lays new eggs, where the Trichogramma is going to reproduce.The laboratory environment for breeding the moth recalls a cupboard without much ventilation and with a slight smell of mold. This is because the moths shed scales, obliging the people who work there always to go about with a mask in the rooms, which also have exhausters installed to filter the air. In another room, there are piles of trays heaped up, with millions of insects that produce eggs that will be put in packaging of paraffin-coated and perforated cardboard, to allow the parasitoids to come out into the fields.

Developed by the project team, this packaging provides for greater security as to the possible changes of temperature or the occurrence of rain and predators, in particular ants, according to Alexandre Pinto. And, according to Parra, it can be patented, because there is nothing similar in the domestic market for marketing eggs with parasitoids.Each capsule, which is placed on the plant itself or on supports, houses some 2,000 eggs with Trichogramma. The date of birth of the insect is forecast on the basis of a technique called thermal demand, which is the ideal temperature for the insect to grow.

“I am capable of defining exactly when it is going to be born by controlling this temperature”, says Parra. This facilitates the life of the customer, who knows when the adults will be ready to leave the capsules. Bug’s researchers have also created a system to check the date that the Trichogramma leaves the capsule. A small portion of the eggs ordered, called bait, is kept at a slightly higher temperature than the rest. “This bait is an indicator of the time at which the material should be put in the field on the following day”, says Danilo.

Quality controlled
According to the principles of the programs for integrated management, the pest can remain in the plantation so long as it does not cause any economic damage. When the population of the pest begins to grow, it is time to intervene in the crop. At that point, there has to be a study to ascertain the quantity of natural enemies that has to be released. The calculations are always made by a sampling of the infested area. For the sugarcane borer, for example, the release of C. flavipes takes place when the intensity of infestation is above 2.5%. For each egg of the pest found in the field, 1,6 Trichogramma is estimated. For tomatoes, a short cycle crop, the capsules can be put in the plantation as soon as the first eggs of the tomato moth ( Tuta absoluta ).

Parra points out that the demand for biological control has grown over recent years in Brazil as well, although the quality of the products does not always correspond to the customer’s expectations. This is because the insects produced under artificial, controlled conditions, cannot always compete with nature.To guarantee the quality of these natural enemies, he advocates that there should always be a strict connection with universities and research institutes in the process of breeding, storing and releasing these insects. “This is the guarantee of the product’s credibility.”  The project’s consultant makes this proposal on the basis of over 20 years’ experience in the area. This knowledge was fundamental for Bug to be able, in such a short time, to win over customers not only in Brazil but also abroad, in countries that already have a tradition in producing insects to fight pests.

Ladybirds were the first

Integrated pest management is a concept that arose in the United States and in Europe in the 60’s, replacing the trend in force those days for applying insecticide to control pests, even if they were not present in large quantities in the crop. “Biological control takes into consideration not only the economic aspect, but also the ecological and social ones, which are important”, says Josê Roberto Postali Parra, a professor at Esalq/USP. Integrated management is a set of measures that have the objective of keeping pests below the level of economic damage.

The use of chemical compounds is permitted, provided that they are not very aggressive to the environment, coupled with other control measures, such as biological control and control by pheromones (substances produced by insects for communication or to serve as a sexual attraction). “The ideal would be to use only a non-chemical option, but sometimes this is not possible, as it depends on the crop”, Parra reckons.

The first insects sold in the United States for biological pest control in gardens and vivariums were ladybirds, in the 1960’s. The great advance in the area took place in the 80’s, but already in 1977 a study carried by American researchers listed 95 companies in the United States and Canada that were selling products intended for biological pest control. In Brazil, the first experiments with this kind of technique, applied to the sugarcane borer, date back to the 1950’s, and were carried out by Esalq’s Entomology Department.

At the time, the researchers began to release native flies, similar to houseflies, to combat the pest. In the beginning, the strategy produced the desired result, but after a few years the biological response fell short of expectations. Accordingly, in the 1970’s, the first strains of the Cotesia flavipes wasp were imported, to be replaced later by other more aggressive ones. But it is only in the last few years that the marketing of natural enemies has begun to arouse interest amongst farmers.

The Project
Mass Breeding and Marketing of  Trichogramma spp and Cotesia flavipes for the Control of Farm Pests (nº 01/08394-0); Modality Small Business Innovation Research Program (PIPE); Coordinator Alexandre de Sene Pinto – Bug Agentes Biológicos; Investment R$ 320,774.00

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