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The broom swept

Simple techniques show how to recover the cacao plantations

from Ilhéus

EDUARDO CESARThe flower of the cacao tree: crops are reborn with intensive care with the soil and the treesEDUARDO CESAR

At the end of August, for the first time, Alex Montenegro Maron visited the cacao plantations of Edvaldo Magalhães Sampaio, in the municipalities of Nilo Peçanha and Piraí do Norte, in the south of the state of Bahia. For hours, Maron, a farmer graduated in law who has spent at least 40 of his 66 years managing the family’s cacao plantations, observed, like a strict teacher, the cacao trees laden with fruit that were spread out everywhere, with practically no sign of witches’ broom, the disease that for ten years has been nourishing itself on the fortune of the cacao producers of Bahia, Pará, Rondônia, Amazonas, Mato Grosso and Acre. Around the middle of the afternoon, the light green shirt heavy with sweat, but seeing that there could lie the way out for recovering the land purchased by the grandfather who had come from the Lebanon and used to sell pans and clothes from house to house before coming a farmer, Maron gave in: “I have never seen anything like it.” His son, Alex Maron, aged 35, was also amazed. It was the first time he had seen his father admit being wrong.

Edvaldo Sampaio, who at the age of 66 goes up and down the hills of the farm without tiring, put in play a set of agricultural techniques that show that it is possible to escape from the attack of the fungus that causes witches’ broom, a disease that earned this name because it leaves the branches as dry as an old broom. His work is matched with other initiatives that are beckoning with the prospect of Brazilian cacao growing raising itself up again along other lines – diversification imposing itself over monoculture, and cacao ceasing to be merely a commodity to be seen also as a refined raw material of higher value, as has been done for decades with coffee. Now, cacao producers and manufacturers of equipment and chocolates are liaising with the purpose of kicking off production, perhaps as soon as next year, of an entirely Brazilian fine chocolate, with more flavor and with a cacao content up to four times greater than today’s – as good or, all right, almost as good as the legitimate Swiss chocolates, those that melt slowly in the mouth.
But cacao growing almost died before showing signs that it may now germinate once again, with more care with the soil and with the trees themselves, in the midst of the desolation left by the witches’ broom. Detected in the Ilhéus region in 1989, the fungus, then called Crinipellis perniciosa and now rebaptized as Moniliophtera perniciosa, made production fall from 390 thousand tons in 1988 to about 100 thousand tons in 2000.

There ended the era of the cacao colonels, as the rich and powerful farmers were called – some of them had in fact purchased the rank of colonel of the Army. They felt unbeatable, to the point of not believing that the dark, humid plantations could be hit by a plague or that the international cacao prices could fall. But they plummeted – from US$ 4 thousand to US$ 600 a ton – precisely when the disease was taking hold of the 600 thousand hectares of the trees that used to supply the raw material for the world’s chocolates.

“We went from millionaires to scavengers” recalls son Alex Maron. The production of the family farm in Itabuna went down from 17 thousand arrobas (32 pounds) in 1986 to a wretched 400 in 1994 – of the hundred employees, four remained. Of the 250 thousand people employed on the almost 30 thousand cacao farms of the region, 200 thousand became jobless. One of the legacies of this flattening of the social pyramid are the houses of bamboo, straw and black plastic, occupied by the unemployed, by the sides of the roads close to Ilhéus, the former Rome of cacao. Another victim was the Atlantic Rain Forest in the south of Bahia, one of the few regions of the Northeast that still houses samples of this kind of vegetation. To pay debts, the farmers felled and sold as timber thousands of trees from the forest that, before, would provide shade for the cacao trees. In those days, between 100 thousand and 150 thousand trees must have disappeared from the native forest.

Edvaldo Sampaio also felt the blow and almost despaired. In one month alone, July 1999, he failed to pick a volume of cacao equivalent to 10 truckloads, 10 thousand arrobas, devoured while still on the tree by the colonies of the fungus that had just arrived at his farms in the environs of Gandu, a municipality near to Ilhéus. For two months, he observed the trees, trying to discover what to do so as not to lose his land, into which, 12 years ago, he had put all the money he had. That year, in September, he did what the other farmers were doing, but at a cracking pace. He worked from dawn to dusk with 25 workers to graft 117 clone stems – of varieties that were resistant to the disease – onto the cacao trees that covered 320 hectares in his four farms (each hectare is equivalent to 10 thousand square meters). Two years later, when he finished, he felt free of a ghost: “Misery is not going to get me again.”

The disquiet took him much further. In a sort of intensive treatment, he reinforced the fertilizing, cut back the trees and induced them to flower, with the purpose of bringing forward the harvest to the first half of the year and thus escape from the attack of the fungus, which is more intense in the second half of the year.  It worked out. Surrounded by plantations taken by witches’ broom, which leaves the leaves a pallid red, as if they had been burnt, his four farms nowadays boast a productivity of up to 80 arrobas of cacao per hectare  on average, four times higher than the average for the state. This year, they should produce 15,200 arrobas, close now to the 19,300 arrobas a year before the crisis. “In two years, when I recover the production” he announces, “I’m going to organize a firework show that all Bahia is going to hear.”


Against the rules
Seen as a madman who only did wrong things until last year, when his results became known through a discussion list about cacao on the Internet, Edvaldo Sampaio is a specialist in breaking rules. When it was recommended to plant aligned clones in rows, this agronomist from Bahia, born in Castro Alves, mixed them up to facilitate the pollination of the flowers and bearing fruit. “I was afraid” he says, “and I thought that this way the risk of going wrong would be lower.” As was seen later, at the cost of a brutal fall in production, the flower-laden trees did not bear fruit, because some varieties of clones were incompatible and did not pollinate the flowers of their own species. While other producers would lop off the original trees for the clones to grow more quickly, Edvaldo would only cut the thinner branches and later on the bigger ones. As a result, on his farm to date, the stumps live with the now fully-grown clones and produce up to ten fruits each. Another daring move was to redeem gypsum, which nobody used any more, to make the roots go deeper and to allow the tree to strengthen itself against the fungus.

“What Edvaldo did shows that there are simple solutions against witches’ broom, scientifically based, and allows us to save at least ten years’ work” comments Gonçalo Amarante Guimarães Pereira, the coordinator of a laboratory at the Biology Institute of the State University of Campinas (Unicamp) and of a network of academic researchers and cacao producers interested in overcoming witches’ broom. Now applied to Edvaldo Sampaio’s four farms – two in the same hot and humid climate of Ilhéus and two with a drier climate – these techniques matched to perfection the conclusions formulated in the laboratory over five years about the mechanisms of the disease and about how to curb the destruction of the trees. It was as if the field tests, which normally follow the scientific work, were already ready at the end of the stage of research in the laboratory.

Very simple, but used at the precise moment, in such a way that they allow the tree to to trick the fungus, Edvaldo Sampaio’s creations are beginning to take the form of tables and graphs – and, now experiencing scientific rigor, are reversing the habitual flow of the production of knowledge, which usually goes from the research institutions to the farms. Since the beginning of this year, a team from Unicamp has been accompanying the behavior of the cacao trees on Edvaldo Sampaio’s farms, to understand precisely the effectives of the measures that he has tested empirically. Entomologist Kazuiyki Nakayama and physiologist Paulo Marrocos are coordinating another group, from the Cacao Research Center (Cepec) of the Executive Committee of the Cacao Crop Plan (Ceplac), which in August started an experiment with 2,400 cacao trees on a farm in the municipality of Uruçuca, near to Ilhéus. They want to evaluate Edvaldo Sampaio’s innovations, to which they have added others, to stimulate the pollination of flowers and generate more fruit. The preliminary results should come out in one year and the final ones in two, according to José Luis Pires, head of the research service at Ceplac. “We don’t have any discomfiture for learning with the farmers” comments Pires, a geneticist from São Paulo who arrived in Ilhéus in 1987, shortly before the overturn of the empire of cacao began.

Confident team
The evaluations of the proposals for controlling witches’ broom are going to extend over the knowledge base that began to be built in January 2000, when Gonçalo Pereira launched the idea of understanding and resolving the cruelest of the cacao tree’s diseases by studying the set of genes – or genome – of the fungus that causes it. His team had been part of the group that sequenced the genome of Xylella fastidiosa bacterium, which causes a serious disease in orange groves. The knowledge and the equipment that they had amassed in the course of this pioneering work nurtured their confidence to deal with a microorganism whose genome soon proved to be 13 times bigger.

One year afterwards, Gonçalo managed to get R$ 1.2 million from the Secretariat for Agriculture, Irrigation and Agrarian Reform (Seagri) of the State of Bahia, and in the following year another R$ 1.3 million, from the Ministry of Science and Agriculture (MCT). Slowly, he went on weaving the research net, adding proven or potential competences from the State University of Santa Cruz (Uesc), in Ilhéus, from Ceplac, from Embrapa’s unit in Brasilia, from the Federal University of Bahia (UFBa) and from the State University of Feira de Santana (Uefs). At the same time, he was meeting cacao producers from Bahia and would spend hours explaining the new perspectives in studying the disease and showing that the alternatives then bandied about were ill-founded, according to which seawater or cow’s urine were excellent against the fungus that was destroying the cacao trees.

The research network expanded in 2003, when Unicamp incorporated a discussion list on cacao – the cacao list. Created in 1999 by farmer Deroaldo Boida de Andrade, the list was about to be extinct. Gonçalo Pereira, who took over as coordinator, saw the list as a form of rapid communication between people connected with the production and trading of cacao, normally disunited. The hundred names soon became 720 – not only of farmers, as at the beginning, but also cacao processors, researchers, university teachers, politicians, journalists, employees of public bodies and consumers. It was by means of the list that the laboratory work and tests in the field converged, in August 2005, onto a single path of the proposals for action against witches’ broom.

EDUARDO CESARHope: a healthy cacao tree, with green leaves and fruitEDUARDO CESAR

It was when Edvaldo sent the other participants on the list a photo of one of his cacao trees, full of cacao. Another name on the list, Edno Querino Câmara, asked him to explain what the score mark was on the trunk of that tree, at chest height. It was ringing, one of the artifices used to induce flowering and to bring forward the crop, to pick fungus-free cacao, still in the first half of each year. It was to even the most important of Edvaldo’s tricks, but it was precisely what the researcher from Unicamp was looking for. Gonçalo already knew that the reproductive cycle of the fungus accompanies rigorously the growth of the plant itself. Months before, he had tried to break this synchrony: he speeded up the maturing of the flowers by spraying the trees with plant hormones. The experiment mobilized about a hundred men and, three months later, came to naught.

When he read the message on the list, though, Gonçalo realized that he had in front of him the answer to the doubts that were torturing him and his team. And he didn’t think twice before shooting off a message recognizing that Edvaldo had found what he had been pursuing for two years, commenting the scientific logic of that technique and concluding, in red: “You have found the solution!” Finally, he asked the farmer to describe in detail what he had done, for the researchers to understand better how this life of reestablishing life in the cacao trees worked.

The coordinator of Unicamp’s Genome and Expression Laboratory overcame his habitual prudence and was so incisive because he had in his hands the map of the disease, drawn up from the genome of the fungus, together with the other research groups from São Paulo and Bahia. In almost 20 scientific articles, the researchers detailed the mechanisms by which the plant defends itself, besides indicating proteins essential for the fungus that, if blocked, could detain the disease.  They had thus revealed the two forms of behavior of the fungus, which at the beginning of the disease, shows and calm and passive personality, feeding on live tissues, and afterwards takes on an aggressive and stormy personality, nourishing itself only on dead tissues.

It was precisely for having already identified genes and biochemical mechanisms by which the fungus attacks and the tree defends itself that Gonçalo Pereira realized that Edvaldo’s techniques ought to work. Months later, visiting the farms, he saw that they really did work. “My success comes from doing everything earlier” Edvaldo Sampaio sums up. He prunes the branches of the cacao tree between October and December, with the fruit finishing to mature on the branch, while producers normally prune them some months later, from January to March, when the spores of the fungus are in the air, awaiting new tissues where they can lodge themselves.

Because of the early pruning, the spores encounter sprouts that are now mature, and without having anywhere to stick to, they die. Even if some spores manage to land on new tissues, they will find a well-nourished tree, because Edvaldo Sampaio fertilizes the soil with urea, rich in nitrogen, in March, when the rains start. The excess of nutrients hastens the change of phase of the fungus, which takes on the more aggressive form and prepares itself to begin nourishing itself on dead tissues. Except that this time the tree is strong, resists, and prevents the development of the fungus. This way makes it possible to bring forward the harvest of the fruits – free of Moniliophtera perniciosa – to May, June and July. The superficial cut on the trunk is done between November 15 and December 15, only for the older cacao trees and every five or six years.

EDUARDO CESARFungus devoured three quarters of the production of cacaoEDUARDO CESAR

Relative wealth
These precautions may not only help cacao growing to be reborn, but also to conserve what remains of the Atlantic Rain Forest in the south of Bahia. Different from other agricultural crops, the cacao tree needs shade – a peculiarity that led to the method of cultivation known as cabruca, in which the cacao is planted in the midst of the natural vegetation. Since from above, the cabruca seems a dense forest, although it is not really a native forest and does not always manage to preserve biological diversity. The main reason is that, for the cacao trees to receive the right dose of humidity and light, all the vegetation closest to the soil is cut and only one out of ten of the highest trees remains. With so little original forest, only the more common species of animals live there, in particular birds and small mammals. ‘the cabrucas reflect the diversity of the neighboring forest” observes Deborah Faria, a biologist from Uesc.

Years ago, Deborah found that a small area of cabruca diluted amidst the mature forest was very rich in animal species, which did not distinguish the limits between the plantations and the forest. In 2002, by means of a study published in February in Biodiversity Conservation, she attested to an opposite situation: wide areas of cabrucas dominating a landscape with little forest are poor in animal diversity. “It is only if they are used properly” she concludes, “that the cabrucas can act to preserve biodiversity.”

Edvaldo Sampaio estimates that 1,500 farmers and researchers have visited his plantations since August last year. Little by little, his bold measures are conquering other lands. “I am applying these techniques on my farm and it’s working” comments Paulo Gonçalves, who farms 350 hectares of cacao in Linhares, Espírito Santo. There are also those who say that these remedies only apply to certain conditions of soil and climate, added to a perfect density and overshadowing of the trees. Or that, for requiring intensive care with the tree and with the soil, they can be expensive – something tragic for the owners, the majority in debt or in litigation with the banks, because of loans that they took to implant the previous ways out, which did not work. Edvaldo warrants that every he does is economical, although the costs are still uncertain.

Nobody has probably been more impetuous than he in testing so many artifices at the same time, but other producers have also created their own recipes for fertilizing and planting and are slowly replacing the trees by clones that are more productive and disease-resistant. Perhaps in this case each one’s discoveries may not be able to be spread, because the resistance of the same varieties of clones varies from one farm to another, probably because of the soil or microclimate, according to an experiment coordinated by Karina Gramacho at Ceplac. She gathered samples of seven types of clones from the farms themselves and infected them with a dose of spores three times larger than that normally used in the experiments. In one extreme case, the resistance of one and the same clone, the EET 392, varied from 20% to 100%, while another, the Scavina6, showed a resistance below 30%, but almost the same for all those selected. Karina verified: “We are dealing with a fungus with an exceptional capacity for adaptation.”