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Hiroshi Noda

Hiroshi Noda: Sustainable agriculture in the Amazon

Agronomist mixes traditional culture with scientific knowledge

Eduardo CesarThe Amazon region taught agronomist Hiroshi Noda another kind of agriculture—one that differs from the widespread practices of the Brazilian Southeast, particularly since the 1960s, when he graduated from the Luiz de Queiroz College of Agriculture at the University of São Paulo (ESALQ-USP). Agriculture was experiencing the powerful technological impact of a massive expansion of machinery used in the field, the use of genetically selected seeds and the growing application of chemical fertilizers. In 1975 he joined the team that Warwick Kerr was assembling at the National Institute for Research in the Amazon (INPA) in Manaus, as a researcher in the field of plant improvement. There in the Amazon, he encountered family agriculture that was based on principles handed down from ancestors, as well as on sustainable management of forest resources.

He started out producing a tomato variety that can be planted in the Amazon, that yields good fruit and that is not susceptible to bacterial wilt—a disease that makes it impracticable to grow them in the region. He then immersed himself in the study of conservation and genetic improvement of non-traditional vegetables developed in the Amazon, as well as in ethnoecological knowledge of local communities.

Noda did his master’s and doctoral studies at ESALQ, interspersed with work at INPA. He retired from INPA in 2013 and, at the age of 71, began to devote himself exclusively to teaching graduate courses in Agriculture of the Humid Tropics at the Institute, and graduate courses in Environmental Sciences and Sustainability at the Federal University of Amazonas (UFAM). In 2014 he received the Bunge Foundation Award for sustainable agricultural productivity, in the Life and Works category. He is married to Professor Sandra Nascimento Noda, of the School of Agricultural Sciences at UFAM, and they have a daughter who is also an agronomist. Noda granted this interview to Pesquisa FAPESP in São Paulo during the Seminar on Sustainable Agricultural Productivity held by FAPESP and Bunge.

Agriculture in the Amazon
Luiz de Queiroz College of Agriculture at the University of São Paulo (ESALQ – USP) (undergraduate, master’s, PhD)
National Institute for Research in the Amazon (INPA) and Federal University of Amazonas (UFAM)
Scientific production:
50 scientific papers, 10 books and 62 book chapters

What has been your contribution to sustainable agriculture in the Amazon?
My training was in Piracicaba, at ESALQ. It was valuable in terms of technology and production. But I went into a traditional agricultural environment in the Amazon, which was quite different from the objectives of the so-called Green Revolution. [In the 1960s, Brazilian agriculture began using genetically selected seeds, expanding the use of farm machinery, growing crops with industrial fertilizers and widely using pesticides to control plant pests and diseases.] I needed to adapt that knowledge in some way. In the Amazon, for example, there are still some species being domesticated for commercial purposes. But the farmers themselves are the ones who are conserving the necessary genetic variation. Genetic improvement techniques, which were generally adopted as a result of the Green Revolution, give rise to increased productivity of new cultivars in response to the use of industrial fertilizers. In the case of the Amazon, the goal is to build a new variety that can propagate in environments where natural soil fertility is restored as a result of the nutrient recycling process triggered by interactions among plants, animals and microorganisms. If we want a plant capable of producing even in poor soil, that plant has to be genetically adapted for growing under those conditions. You have to select lineages that can meet that requirement. In the Amazon you have to adapt plants to local conditions, such as high temperature and high humidity throughout the year. I learned this by going to the farmers. Since farming there is done by traditional methods, the farmers do not use the inputs that were introduced in the Green Revolution.

Why not?
In the local communities, they use what is available. Plant nutrients have to be natural. In Amazonian soil, the plant fertilization process occurs through a form of nutrient recycling. The forested areas have permanent, arboreal and perennial species. Recycling occurs in this way: the aerial part of a plant carries out photosynthesis and produces fruit, and the material that falls to the ground is recycled by macrofauna such as termites and ants. The insects grind up the material, which then becomes incorporated into the soil. The microorganisms that live in the soil mineralize the organic matter—a  process that is essential to the release of nutrients to plants. This is the way that a cultivated plant gets its nutrients through recycling. Consequently, when toxic products such as herbicides are used, they cause problems in the macro and mesofauna populations and in the microorganisms that live in the soil. The effect of the herbicide is to kill invasive plants. But it also eliminates the microorganisms that are responsible for recycling nutrients.

Why are Amazonian soils so poor?
They are poor because of the mineral composition of kaolinite clay. Because of their physical and chemical characteristics, the soils have a low capacity for cation exchange [cations are positively charged ions], and therefore the nutrients dissociated in the soil solution percolate down to the deepest layers along with rainwater. This does not happen in the case of purple soil, the soil type that occurs in the Brazilian Southeast; its clay content has a high cation retention capacity. In the Amazon there has to be vegetation coverage to protect the soil from the effects of rainfall, and that organic layer also has to be able to retain nutrients. And what is the ideal system? Agroforestry, a mix of perennial and annual plants that make use of the treetops to protect the soil. Below the trees are the annuals, which benefit from partial shade. It could be a combination that includes forest species such as andiroba and copaiba, for example, and plants intended for human consumption. The arrangement of this system can vary in space and time, depending on each plant’s requirements. For example, when an açaí palm is in its embryonic stage, it needs shade; but later on it requires sun. This is one of the big problems that arise from deforestation of the Amazon Region. If the soil is exposed, its protective layer is eliminated.

What role do Amazon communities play in preserving the soil?
It is the traditional culture that follows ancestral principles. Human survival in the Amazon requires food production and an area for fishing and hunting, so that people can have a source of protein. Farming must be permanent, otherwise people would have to become nomads in search of food. There are communities where families have been in the same place for more than 30 years. The production system must be sustained, and all of the environmental ingredients necessary to achieve that will have to be recycled. When you plant annual species, this is possible if you have a small growing area, and at the same time leave some areas unplanted to allow for soil recomposition in previously cultivated environments.

So leaving land to lie fallow is our way of regenerating a secondary forest, i.e., the forest that grows after the natural vegetation has been cut down?
Yes. When a farmer stops producing on land he sets aside, the soil regains all the functions of a forest. This occurs because there is a reservoir of seeds from the forest that can then repopulate the area that had been used for growing. The practice makes it possible to use the soil again for agricultural production. We often hear it said that farmers destroy the forest, but that is not what happens. In our surveys and studies, we’ve seen that a family’s working area is one hectare, because they can’t farm an area larger than that. A workforce is the only input a farmer can provide in order to produce. If there is a family-owned area focused on traditional farming alongside an area used for harvesting timber, the situation makes that kind of farming unfeasible. Small farmers are not the ones who cause deforestation. Other agents do it. We learned these things by living among family farmers. Water conservation and biodiversity are also important to them, so that the family farm will maintain ongoing food security.

What is agrobiodiversity?
Agrobiodiversity refers to all of the organisms that live in the space used by agriculture: plants, microorganisms, pollinators. They could also be pests. An insect that feeds on a plant is not a pest; that problem arises from high population density caused by parasites’ reproductive capacity in areas of extensive monoculture. When the forest is heterogeneous, a given insect or other microorganism does not cause damage. All of these organisms are important for agriculture. Nothing exists in isolation. A long time ago I saw a paper by a group of professors at the USP School of Medicine in Ribeirão Preto, about pollinators in soybean farming. Their findings showed that bees are very important for soy production. But soybeans do not need bees for pollination because they self-pollinate. Yet the bees’ presence increased yield. That was the lesson learned.

You were born in Pompeia, São Paulo State, got a degree in agronomy and then studied philosophy. How did that career path come about?
I graduated in 1968, at a time when there were few jobs for agronomists. But the São Paulo State Bank [Banespa], a state-owned enterprise, created a technical assistance network, and I went to work with farmers who were getting Banespa loans. I stayed about nine months in the city of Presidente Epitácio, in western São Paulo State. I was enjoying the work, but late that year—1969—I applied for a job at Petroquisa, a Petrobras subsidiary that no longer exists, which was making fertilizers in Cubatão, in the Santos Metropolitan Region. I went to live in Santos to work in technical assistance in Cubatão.

Technical assistance for farmers?
It was targeted to cooperatives because Petroquisa had a network for marketing lime nitrogen—ammonium nitrate mixed with limestone—which was highly sought-after. And Petroquisa’s points of sale were the cooperatives. We served farmers, and I stayed there for six years. Since I wasn’t doing anything at night, I went to the Catholic University of Santos.

How long did you stay at the company?
I was there six years. When I graduated, I wanted to work in Green Revolution extension, which involves the whole assistance apparatus—not just technical, but social as well. That was a U.S. model that was being introduced in Brazil. It was something I wanted to do, although I liked the part that had to do with improvement and genetics. At that time, I read an interview in Veja magazine in 1975, by Professor Warwick Kerr [former professor at USP and other universities and first scientific director of FAPESP], who had recently been appointed director of INPA. He was building a team, and I sent him a letter saying I’d like to work at the Institute. A week later, I received a reply asking if I’d like to put together a team of people to work on improving seeds for the Amazon Region. And if I went there, I could finish my education, get a master’s and a PhD. I talked with my fiancée, because our wedding was just two weeks away. Surprisingly, she said, “Let’s go.”

What was that move like?
I always say that in population genetics there is something called the founder principle, which says that the future of a population is dependent on the genes of its founders. And there we had two founders who were excellent. One was Warwick Kerr and the other was Alejo von der Pahlen, an Argentine of German ancestry. He was an experienced researcher, having been director of the Argentine National Institute for Agricultural Technology (INTA). We joined up with them. Everything about establishing the research program, biodiversity, agriculture for the Amazon Region, and the new way of thinking about how to plant crops—all of it was already there in their heads.

Plant improvement led you to produce a new regional cultivar. How did you create that variety?
Bacterial wilt caused by bacteria of the species Ralstonia solanacearum attacks plants of the Solanaceae family, such as tomatoes, eggplant and sweet peppers all over the world, anywhere with the environmental features of the Amazon. The infectious agent causes disease in many cultivated plants and in other families as well, including in non-domesticated species.

Why is that?
Because there’s always a lot of diversity in this bacterium. If you plant in São Paulo in a warmer place, it will show up. It’s not specific to the Amazon; it occurs everywhere in the world. In a monoculture system, alongside one plant is another one exactly the same, and it’s easier for an epidemic to occur—it will go on spreading. But a plant in the forest, for example, has a different species as its neighbor, so the bacterium is limited.

And the tomato adapted to the Amazon?
After a long while, I obtained a new tomato variety. Even to this day there is a lot of research on this. When you’re working on improving resistance, there are two types of reactions you might run across. You have the host, which is the tomato plant, and the bacterium. If we insert a resistance gene into the tomato plant, we make it resistant to a biotype of that bacterium. It’s a relationship or interaction called gene to gene. Since the pathogen population is quite variable, at a certain time a mutant appears that might be able to put an end to the tomato plant’s resistance. The problem with the appearance of the mutant is that I wouldn’t be able to produce a tomato plant capable of solving this problem of specificity of resistance to the virulence of the pathogen. So the approach I chose was to insert into the tomato plant what we call horizontal or polygenic resistance. In order to do this, it was necessary to access the collections of cultivated and wild tomato varieties that exist around the world. For example, in the United States there is a germplasm bank with a large collection of tomato seeds from all over the world. We contacted the head of the collection and asked if there was some material that could be used in the Amazon. We obtained access to existing materials in other institutions in Brazil and other countries and tested it in Manaus. From 1975 to 1983 we conducted screening tests to determine the potential for resistance to the bacterium. Tomato plants are an autogamous [i.e., self-fertilizing]  species, and we had to wait until the third generation to find out if bacteria-resistant plants would appear in the segregating generations and would, at the same time, produce consumable fruit. We obtained a variety that was highly resistant. It was a combination of material from the University of Hawaii and from French Guiana. It worked, and we went on with the selection process. In the Amazon, we started the testing with the growers, because that’s where the plants would be commercially grown. We observed that the tomato plant was indeed resistant, but some lineages produced no fruit. We came to the conclusion that it was an issue of tomato flower abortion, which occurs when the tomato plant is grown in high-temperature environments. We were lucky because the selected material included some progeny [descendants] that also showed heat resistance. We used it and it worked.

Did the tomatoes consumed in the Amazon prior to that come from other parts of the country?
No. Bacterial wilt is a widespread problem. What were they doing? There was an Adventist technical school that was using an American technology which involved putting them in a box above the ground and sterilizing them with methyl bromide. It killed all the microorganisms inside. But the product is very hazardous and has even been banned. They were able to produce this way using two American cultivars, but then diseases started appearing that they couldn’t control, and the system was abandoned. Tomato plants have been highly genetically manipulated, and that has made them not very resistant to growing in natural environments, and very dependent on environmental control in the planted area.

The tomato you developed is named Yoshimatsu. What does that mean?
I had to give it a name in order to identify what we did, not for any gain, but because you need a reference to how it was obtained. I decided to call it Yoshimatsu after my parents—my father Yoshimasa, and my mother Matsu.

Unlike most other varieties, Yoshimatsu seeds are provided free of charge. Why?
First of all, I think that since INPA is a public institution devoted to scientific research, all of the scientific and technical knowledge and products it creates should be intended for the Brazilian people as a matter of priority. I also think that the Yoshimatsu tomato will never be produced by a company, because the number of seeds necessary to supply certain regions, such as the state of Amazonas, is quite small. Ten kilos of seeds will often suffice.

Do the farmers produce their own seeds?
Part of the planted area can be reserved for growing seed for sale and planting for the next season. But you have to be careful, because there can be cross-breeding among plants of different varieties. We have a pilot project aimed at subsidizing public policies for seed production, targeted to family agriculture financed by the CNPq [National Council for Scientific and Technological Development]. The goal is to transfer the technology to farmers and connect this into a state system. Some growers will produce seeds and sell them to government agencies that provide technical assistance and rural extension services, which will then distribute them to farmers free of charge.

In what other ways have you contributed to agriculture in the Amazon?
We are working with non-traditional vegetables. There are the traditional ones, like tomatoes and peppers, that are important. They’re not local, but they are important. A number of inland families eat tomatoes, make sauces, etc. So we work on genetically adapting them to a humid tropical environment. As for local plants, we have taro root, the vinegar plant and jícama, which is an interesting plant because it can fix atmospheric nitrogen and turn it into protein, so it doesn’t need to use nitrogen fertilizer. People eat the jícama’s tuberous root, which contains up to 9% protein, as compared to cassava, which contains 1% by dry weight. With fruit, we work to conserve and maintain genetic variability and participatory improvement. This is what we’re doing with sapota fruit, a species from western Amazonia grown in the Alto Solimões area but not marketed very much. It’s one of the fruits that could be expanded to a wider growing area. We are working on participatory improvement and we’re going to have a dialogue with the farmers about these issues, learn with them and come away with knowledge about the features that should be considered in the improvement process. How to make a fruit yellower, darker, sweet or not sweet, and also set up a conservation system in the areas of impact.

What is a conservation system?
It’s intended to maintain a species’ genetic variability. Because a species is not just one plant or one population. That’s not enough, because if some event occurs that jeopardizes the survival of the species, there won’t be enough variation to overcome these problems. If a climate change event occurs and affects the plant, and there is no variation, there is no way to adapt it to the new conditions; there’s not enough variability, and the possibility for extinction is very high. In the case of the açaí palm from Amazonia, it grows well on dry land, but it is also found in humid várzea floodplain environments. One time I went to pay a visit to a farmer. He knew that the açaí palm is a dryland species, but we saw one in the várzea and we asked the farmer—the issue of ethnoknowledge comes into the picture here—why the plant is in the várzea if it’s a dryland plant. He said that it’s a resistant plant. It has adapted because it went through a selection process. In an açaí population, seed dispersal is natural and seed goes everywhere. If a few of them fall in a particular location and are not adapted, nature selects them out. If an individual plant is adapted, it will stay, and so the frequency of adapted individuals [genes] gradually increases.

How do you view local participation in your work?
We’re working on cultural reaffirmation because their culture has enabled these species—which number in the thousands and were domesticated by their ancestors—to continue to exist there. That culture is responsible for maintaining agrobiodiversity. If the culture changes, the question of conserving biodiversity will no longer be meaningful.

What would be different?
It’s different from ex situ conservation, which is conservation outside the area where the species occurs. The INPA has a peach palm collection, which is very difficult to maintain because the specimens were collected in Central America, Colombia and Peru, and were taken to an experimental station. It’s hard because they have to keep the plants alive outside the setting where they occur.

Do you think Brazil has to make a greater commitment to cultural reaffirmation?
To do that it has to recognize that one of the functions of family farming and environmental protection areas is to conserve the resources that are there within the area, not just to produce. Brazil nuts, for example, come mainly from extractivism, although the function of the Brazil nut reserves is not just to produce but also to maintain the resource. That has been the policy of the Ministry of the Environment. There’s also the Family Allowance Program and the Forest Conservation Allowance Program, which help carry out that conservation work.

Would participatory genetic improvement be useful as well?
Interaction with farmers is very important, because they are the holders of local knowledge. If those elements of nature are there and are being conserved, it is because someone—human culture—enabled it. Knowing how they do this is important. Improvement is an evolutionary process; man conducted this selection—I want this or I want that. The conducting is man’s doing, and so is identification. Participation of traditional knowledge holders is important and, since that material is in community and public areas, the decision about how to improve and maintain should come from the farmers themselves. We interact and say that if they want to improve a species, and if they intend to market it, we’ll do it with them. We are there as consultants. We make an effort to respect and decodify traditional knowledge, promote its integration with scientific knowledge, and at the same time, work towards the cultural reaffirmation of the people of the Amazon.