Mycotoxins are poisons produced by common mold fungi. The best known examples are aflatoxins, produced by Aspergillus, which are of increasing concern worldwide because they contaminate Â many types of stored foods, including groundnuts (peanuts), manioc, maize (corn) and chilli. Aflatoxins affect the health of people and animals and are powerful carcinogens if Â enough is consumed. Like many successful poisons, aflatoxins are invisible and tasteless, so they are tricky to manage.
The other week, I was in Chuquisaca, Bolivia, with Paul and Marcella from Agro-Insight, making a video for farmers on how to manage molds and reduce contamination of food. Part of the solution is surprisingly low-tech.
The first step is to recognize the molds. They look like a dark green powder, growing between the pink skin of the peanuts and the white layer of the shell around them. Farmer Dora Campos explains that the people in her village, Achiras, used to dismiss the molds, saying simply that the pods were rotten. Farmers would salvage the bad nuts by feeding them to pigs or chickens, and some people would even eat the rotten nuts. Thanks to what theyâve learned in recent years, the villagers now bury the spoiled peanuts.
Aspergillus survives on organic matter in the soil, within easy reach of peanut pods, for example. Antonio Medina showed us how he dried his peanut pods off the ground, as soon as they are harvested, to stop the mold contaminating them. This keeps the nuts as clean and dry as possible.
Like most fungi, Aspergillus needs water to thrive. Don Antonio shows us how the farmers pick through the whole pile of harvested peanuts, after drying, when the pods are cleaner and the bad ones are easier to spot. The farmers go through the harvest one pod at a time, discarding all of the spoiled or discolored pods. It takes time, but it is a technique that smallholders can use to produce a high-quality product, based on thoughtfulness and hard work.
Agronomist Edwin Mariscal is trying a simple solar dryer with many of the farmers he works with. Mr. Mariscal introduces us to Santiago GutiÃ©rrez, who has built one of the dryers: a wooden frame raised off the ground and covered with a sheet of tough, sun-resistant plastic. Mr. Mariscal has been working with similar dryers in the field, with farmers for years. The dryers started as a metal version for drying peaches, but experience showed that the dryers worked just as well if they were made from wooden poles cut on the farm.
Don Santiago, and his wife Emiliana, explain that the dryer works beautifully. Peanuts dry even in the rain. The family can also put maize and chilli into the structure, to dry those foods free of aflatoxin.
You can keep deadly aflatoxins out of food by following a few simple principles, including harvesting on time (not too late, or the Aspergillus has more time to get into the pods). Keep the produce off the ground. Dry it out of the rain and remove the moldy pieces. Store produce in a cool, dry place, off the floor.
Thanks to FundaciÃ³n Valles for information for this article, and for supporting our filming in the field.
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EVITAR UN ASESINO SILENCIOSO
Por Jeff Bentley, 12 de febrero del 2017
Las micotoxinas sonÂ venenos producidos por mohos de hongos comunes. Los ejemplos mÃ¡s conocidos son aflatoxinas, producidas por Aspergillus, que son de interÃ©s actual porque contaminan muchas clases de alimentos almacenados, incluso manÃs (cacahuates), yuca, maÃz y chile (ajÃ). Las aflatoxinas afectan la salud de la gente y de los animales y son Â cancerÃgenos poderosos si se consume lo suficiente. Como muchos venenos exitosos, las aflatoxinas son invisibles y sin sabor, entonces son difÃciles de manejar.
La otra semana, estuve en Chuquisaca, Bolivia, con Paul y Marcella de Agro-Insight, haciendo un video para agricultores sobre cÃ³mo manejar mohos y reducir la contaminaciÃ³n de los alimentos. Felizmente, parte de la soluciÃ³n es el uso de tecnologÃa apropiada.
El primer paso es reconocer a los mohos. Parecen un polvo verdusco oscuro, que crece entre la piel roja del manÃ y la capa blanca de la cÃ¡scara. La agricultora Dora Campos explica que antes, la gente de su comunidad, Achiras, no daba importancia a los mohos, diciendo simplemente que Â las vainas estaban podridas. Los agricultores rescataban los manÃs malos, dÃ¡ndoles de comer a sus chanchos o gallinas, y algunas personas hasta comÃan los granos podridos. Gracias a lo que han aprendido en los Ãºltimos aÃ±os, ahora los comuneros saben enterrar los granos podridos.
Aspergillus sobrevive en la materia orgÃ¡nica del suelo, al alcance de las vainas de manÃ, por ejemplo. Antonio Medina nos mostrÃ³ cÃ³mo Ã©l secaba sus vainas en un toldo al cosecharlas, para evitar que el moho las contamine. Eso ayuda a mantener a los manÃs limpios y secos. Como la mayorÃa de los hongos, el Aspergillus necesita agua para vivir.
Don Antonio nos muestra cÃ³mo los agricultores escogen todos los manÃs cosechados, despuÃ©s de secarlos, cuando las vainas son mÃ¡s limpias y es mÃ¡s fÃ¡cil ver las malas. Los agricultores revisan toda su cosecha, una vaina a la vez, descartando las vainas malas o descoloridas. Toma tiempo, pero es una tÃ©cnica que los campesinos pueden usar para producir un producto de alta calidad, trabajando en forma consciente.
El Ing. Edwin Mariscal estÃ¡ probando un simple secador solar con varias familias. El Ing. Mariscal nos presenta a Santiago GutiÃ©rrez, que ha construido uno de los secadores: una tarima de palos como una mesa, cubierto de una hoja de plÃ¡stico fuerte y resistente al sol. El Ing. Mariscal ha trabajado con secadores parecidos en el campo, con agricultores, durante varios aÃ±os. Los secadores empezaron como una versiÃ³n metÃ¡lica para secar duraznos, pero la experiencia mostrÃ³ que los secadores funcionaban igual si se hacÃan de palos cortados en la zona.
Don Santiago, y su esposa Emiliana, explican que el secador funciona bien bonito. Los manÃs secan hasta en la lluvia. La familia tambiÃ©n lo usa para secar maÃz y ajÃ, para evitar aflatoxina en ellos.
Se puede mantener los alimentos libres de las aflatoxinas letales siguiendo unos principios sencillos, como cosechar a tiempo (no muy tarde, o el Aspergillus tendrÃ¡ mÃ¡s tiempo para entrar a las vainas). No secar el producto en el suelo. Evitar que entre la lluvia al producto y saque las piezas podridas. Almacene en un lugar seco y fresco, no en el piso.
La FundaciÃ³n Valles nos proporcionÃ³ informaciÃ³n para este artÃculo, y apoyÃ³ nuestra filmaciÃ³n en el campo.
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In the The Field Guide to Fields, Bill Laws colourfully depicts how fencing is a global and age-old practice. Fences mark field boundaries and they stop farm animals from straying. Â Fences make it easier to look after animals but enclosed areas can make them more vulnerable to wily predators. During our recent trip in Bolivia we learned how farmers have come up with a clever way to protect their sheep from foxes.
After an amazing drive along winding mountainous roads of Chuquisaca, crossing a narrow improvised bridge just about the width of the car, and wading through riverbeds, we arrive at the farmhouse of doÃ±a Basilia Camargo early in the morning. Her husband is about to leave to mend some fences around their fields further up in the mountains. DoÃ±a Basilia and her husband keep their 15 sheep near the house in a corral fenced with brushwood and barbed wire.
I ask about the miniature house that has been built into the corral. The little mud house has a slanted roof to let the rainwater glide off, a small window and a door leading to the coral. It looks like a house for chickens, or a toy made by the children, but doÃ±a Basilia explains that it has a more serious purpose. She is raising a dog to protect the sheep from foxes.
DoÃ±a Basilia gets into the corral, and shows us an even smaller shelter in one of the corners. She calls it a ânest,â and she wriggles her hand through the small opening and brings out a little puppy that is only two weeks old, barely big enough to stand on its own legs. Most people only bring home puppies that have been weaned, but this puppy has a ewe as a substitute mother.
âI make the ewe lie down and then let the puppy suckleâ, she explains. The dog will continue to suckle as it grows older, and will bond with the flock, following them to pasture and back to the corral.
It all has been properly planned. The small mud house that we saw along the fence is to become the house for the dog, once it has become bigger. When the puppy is old enough to follow the sheep, doÃ±a Basilia will take him with her, and spend two weeks herding the sheep. That should be enough for the dog to learn to tend the flock on his own.
DoÃ±a Basilia used to have a sheep dog but it died three years ago, and she has been trying since then to raise another one. Some dogs have died and others refuse to be trained.
She points to three dogs napping in the sun. âI tried training that dog there, but he is lazy and doesnât like to walk. He goes out with the sheep, but comes back and just lies down near the house. I hope I will have better luck with this one,â she confides in us smilingly.
So while brushwood and barbed wire fences may be enough to keep the sheep in, a specially trained dog could defend them from foxes, both in the field and in the corral, where the dog will be sheltered from the cold in his own little house. Once more we were reminded of the marvelous ingenuity of local farmers to use their available resources to protect their valuable flock.
Bill Laws, 2010. The Field Guide to Fields. Hidden Treasures of Meadows, Prairies and Pastures. Washington: National Geographic.
A plant has a personality and, like people and countries, some have stronger characters than others. Take the lupin bean (Lupinus mutabilis), for example. It is an oddly erect legume that forms a sort of cone shape, and its glorious flowers make the plant wildly popular with gardeners in many countries. In Bolivia it is called âtarwiâ, from Quechua, the language of the Incas.
While making a video in Bolivia, my colleagues and I asked doÃ±a Eleuteria in the village of Phinkina to tell us what she planted after harvesting tarwi. She surprised me by saying that sometimes she followed tarwi with potatoes. Thatâs astounding, because potatoes are such a demanding crop that Andean farmers often rest the soil for years before planting a field to potatoes. Otherwise the soil may be improved by adding tons of chicken manure. Bolivian farmers in the Andes donât buy manure for other crops, just the fussy and valuable potato.
I followed up by asking Reynaldo Herbas, from the village of Tijraska, if he had ever planted potatoes right after tarwi. âYes, and it does very well. Planting tarwi is like fallowing your soil, or like using chicken manure,â he explained.
Tarwi seeds are also rich in oils and proteins and doÃ±a Eleuteria regularly feeds lupin beans to her children. Like some other Bolivians doÃ±a Eleuteria make a nutritious snack by boiling the seeds, but itâs a lot of work. The grains need to be soaked in water for three days before boiling, then left in the running water of the river for several days to wash out the bitter alkaloids.
Agronomist Juan Vallejos from Proinpa (a research institute) confirmed that tarwi takes a lot of water to process. This is ironic, because tarwi is recommended for dry areas with impoverished soils. Sweet varieties without the bitter alkaloids do exist, but in Bolivia the search for these sweet lupins is only just starting.
While visiting doÃ±a Eleuteria to learn about processing seed, she showed us how to pick out the bad grains of tarwi, to ensure that the crop planted from them would be healthy. (The main disease is anthracnose, caused by the fungus Colletotrichum gloeosporioides). We asked doÃ±a Eleuteria what she did with the diseased grains. We thought that she might say that she buried them to keep the disease from spreading. But no, she buries the discarded grains because raw lupin beans are toxic, whether they are healthy or diseased.
âI do bury them,â she explained, âbecause they are so bitter that if the chickens eat them they will die.â
Agronomist Vallejos explained that tarwi plants are so packed with alkaloids that sheep and cattle will not touch a crop growing in the field. However, the lupin plant is drought resistant and even withstands hail, which often mows down other food crops in the Andes. Local governments in Bolivia are starting to promote tarwi as a way of adapting to climate change.
A plant may have a complex personality, with sterling qualities as well as some tragic defects. Tarwi or lupin is in many ways a perfect crop: well-suited to the punishing climate of the High Andes while nutritious for people and good for the soil. The downside is that you need lots of water to process the beans and to leach out the poisons that can kill your unsuspecting chickens.
For this story in Cochabamba, Bolivia, I was fortunate enough to be accompanied by Paul Van Mele and Marcella Vrolijks of Agro-Insight and Juan Vallejos and Maura Lazarte and others from Proinpa. The visit was funded by the McKnight Foundation.
Calisaya, J.J., Â M. Lazarte, R. Oros, P. Mamani 2016 âDesarrollo Participativo de Innovaciones TecnolÃ³gicas para Incrementar la Productividad de los Suelos AgrÃcolas en Regiones Andinas Deprimidas de Bolivia.â Read at the Community of Practice meeting, McKnight Foundation, Ibarra, Ecuador 11-16 July. See the paper here.
The farmer training video âGrowing a good lupine cropâ will be hosted on the Access Agriculture website shortly in English, Spanish, Quechua and Aymara.
CULTIVO CON CARÃCTER FUERTE
Por Jeff Bentley
29 de enero del 2017
Una planta tiene una personalidad, y como la gente y los paÃses, algunos tienen mÃ¡s carÃ¡cter que otros. Considere el lupino (Lupinus mutabilis), por ejemplo. Es una leguminosa que crece casi en forma de cono, y gracias a sus flores gloriosas la planta es querida por jardineros en muchos paÃses. En Bolivia se llama âtarwiâ, del quechua, el idioma de los Incas.
Mientas mis colegas y yo filmÃ¡bamos un video en Bolivia, pedimos que doÃ±a Eleuteria en la comunidad de Phinquina nos contara quÃ© sembraba despuÃ©s de cosechar el tarwi. Ella nos sorprendiÃ³ cuando dijo que a veces sembraba papa despuÃ©s del tarwi. Es increÃble, porque las papas son tan exigentes que muchos agricultores andinos descansan el suelo durante aÃ±os antes de sembrar papas. Si no, el suelo tendrÃ¡ que mejorarse agregando toneladas de gallinaza. Los agricultores en los Andes bolivianos no compran gallinaza para otros cultivos, solo la mimada y valiosa papa.
Luego le preguntÃ© a Reynaldo Herbas de la comunidad de Tijraska, si Ã©l jamÃ¡s habÃa sembrado papas despuÃ©s del tarwi. âSÃ, y produce muy bien. El sembrar tarwi es como descansar sus suelo, o como usar gallinaza,â explicÃ³.
Los granos de tarwi son ricos en aceites y proteÃnas y doÃ±a Eleuteria a menudo los da de comer a sus hijos. Igual que algunas otras bolivianas, doÃ±a Eleuteria hace una merienda nutritiva con los granos cocidos, pero cuesta mucho trabajo. Los granos tienen que remojarse en agua durante tres dÃas antes de cocerse, para despuÃ©s dejarlos en el chorro del rÃo durante varios dÃas mÃ¡s para expulsar los amargos alcaloides.
El Ing. AgrÃ³nomo Juan Vallejos de Proinpa (un instituto de investigaciÃ³n) confirmÃ³ que el tarwi toma mucha agua para procesarse. Es irÃ³nico, porque el tarwi se recomienda para zonas secas con suelos empobrecidos. Existen variedades dulces, sin los alcaloides amargos, pero en Bolivia reciÃ©n empieza la bÃºsqueda por esos lupinos dulces.
Cuando visitamos a doÃ±a Eleuteria para aprender cÃ³mo ella procesa la semilla, nos mostrÃ³ cÃ³mo quitar los granos malos de tarwi, para asegurarse que el cultivo que siembra serÃ¡ sano. (La enfermedad principal es la antracnosis, causada por el hongo Colletotrichum gloeosporioides). Preguntamos a doÃ±a Eleuteria quÃ© hacÃa con los granos enfermos. PensÃ¡bamos que dirÃa que los enterraba para que las enfermedades no se diseminaran. Pero no, ella entierra a los granos descartados porque los granos crudos de tarwi son tÃ³xicos, bien sea sanos o enfermos.
El Ing. Vallejos explicÃ³ que las plantas de tarwi estÃ¡n tan cargadas de alcaloides que las ovejas y vacas no tocan al cultivo en la parcela. Sin embargo, la planta de tarwi es resistente a la sequÃa y hasta aguanta a la granizada, que a menudo arrasa con otros cultivos en los Andes. Los gobiernos locales en Bolivia empiezan a promover el tarwi como una adaptaciÃ³n al cambio climÃ¡tico.
Una planta puede tener una personalidad compleja, con cualidades de oro igual que algunos defectos trÃ¡gicos. El tarwi o lupino en muchas maneras en el cultivo perfecto: bien adaptado a los desafÃos del clima altoandino, mientras es nutritivo para la gente y bueno para el suelo. Su lado oscuro es que requiere de mucha agua para lavar los venenos que pueden matar a tus gallinas inocentes.
Para escribir este cuento en Cochabamba, Bolivia, tuve la buena suerte de estar acompaÃ±ado de Paul Van Mele y Marcella Vrolijks de Agro-Insight y Juan Vallejos y Maura Lazarte y otros de Proinpa. La visita se financiÃ³ por la McKnight Foundation.
Para leer mÃ¡s
Calisaya, J.J., Â M. Lazarte, R. Oros, P. Mamani 2016 âDesarrollo Participativo de Innovaciones TecnolÃ³gicas para Incrementar la Productividad de los Suelos AgrÃcolas en Regiones Andinas Deprimidas de Bolivia.â Trabajo presentado en la reuniÃ³n de la Comunidad de PrÃ¡ctica, McKnight Foundation, Ibarra, Ecuador 11-16 de julio. Ver la presentaciÃ³n aquÃ.
Para ver mÃ¡s
El video educativo para agricultores âProducir tarwi sin enfermedadâ se colocarÃ¡ pronto en el sitio web de Agriculture en inglÃ©s, espaÃ±ol, quechua y aymara.
In most countries, men and women have different styles of speaking. But is it possible for a community to have two completely different languages, one for men and one for women, not just for one generation, but sustained for a long time?
If such diglossia (a dual language system) is possible, imagine the decisions one would have to make while engaging with such a community. Makers of educational videos might have to make two soundtracks for a single community. An agricultural extensionist would have to choose which language to use for a talk.
As strange as it may seem, at least one society did come close to having two, gender-based languages, which were spoken over several generations. Â In the 17th century, the people of the Caribbean Island of Dominica told a story that they said took place some generations before the coming of the Europeans, when the islands of the Lesser Antilles had been inhabited by people who spoke an Arawak language. Then the islands were attacked by canoe-loads of men who spoke a Carib language. The invaders killed the local men, and then settled down with the women.
The two languages were extremely different, but the children born after the invasion grew up speaking both of them. All children learned the Arawak language of their mothers, but when the boys became teenagers they started spending more time with the men, and began to speak Carib among themselves. The Islanders developed a version of Carib that became a language for men only.
In 1665, Father Raymond Breton, a French missionary, published a two-volume dictionary of the language then spoken on the islands of Dominica and St. Vincent. The dictionary specified whether each word was used by men, or by women.
Various scholars have questioned the historical accuracy of the Carib invasion story. It is possible that the menâs language originated through trade or migration. Â We will never know if Carib men of the 13th century once rampaged across the island beaches, murdering Arawak men and capturing women. There is no historical or archaeological evidence for (or against) this story. Yet the linguistic data are well documented. There is no doubt that in the 1650s, over much of the Lesser Antilles, men and women spoke in two remarkably different codes. The two genders used the same sounds, and most of the same grammar, but menâs words were from Carib, and womenâs words were from Arawak. (The men could speak the womenâs language, and would speak it when socializing with women. The menâs language was only used between men).
If you could time travel to the Island of Dominica in the 17th century, and were able to speak the full range of menâs and womenâs languages, a talk with the whole community would sooner or later switch to the womenâs language, because it was everyoneâs first tongue.
In agricultural extension today, sometimes it helps to create a space where women can easily speak up, so that their concerns can be addressed. It is easy to start to think that men and women are very different, but it is also worth remembering that in some ways we are the same, and that language can unite us.
Allaire, Louis 1980 âOn the Historicity of Carib Migrations in the Lesser Antilles.â American Antiquity 45(2):238-245.
Boucher, Philip P. 2009 Cannibal Encounters: Europeans and Island Caribs, 1492â1763. Baltimore: Johns Hopkins University Press.
Davis, Dave D. and R. Christopher Goodwin 1990 âIsland Carib Origins: Evidence and Nonevidence.â American Antiquity 55(1):37-48.
Taylor, Douglas 1954 âDiachronic Note on the Carib Contribution to Island Carib.â International Journal of American Linguistics 20(1):28-33.
Taylor, Douglas R. and Berend J. Hoff 1980 âThe Linguistic Repertory of the Island-Carib in the Seventeenth Century: The Men’s Language: A Carib Pidgin?â Â International Journal of American Linguistics 46(4):301-312.
Watch a video on women in agricultural extension, here.
About 10% of greenhouse emissions are from agriculture, especially from wet rice cultivation. Rice plants need a lot of nitrogen which is often provided as urea, a chemical fertilizer which is usually broadcast by hand into the irrigation water: this is easy, but wasteful. Some 60% of the nitrogen fertilizer is lost as it is transformed into gases and enters the atmosphere. Some nitrogen is washed away by irrigation water. A practical alternative known as âurea deep placementâ makes much better use of nitrogen.
Urea usually comes in round grains, the size of fine gravel. For deep placement, the small grains are pressed into larger, oval pellets, about the size of your thumbnail. The farmer pushes these âsuper granulesâ of urea into the soft soil, between four rice plants. This deep placement puts the urea underground, near the plantsâ roots, so less nitrogen escapes into the air and water. The rice crop yields more and the farmers save money because they only need to use half as much fertilizer.
The efficiency of urea deep placement was demonstrated by 1980. The practice has not been adopted more widely because of the lack of supply of the super granules, the additional labor required and the difficulty of correctly placing the super granules in the field. Â But by the early 2000s, urea deep placement re-emerged in parts of Asia. The manufacture of small briquetting machines meant that the super granules could be made at the village level, and has led to a dramatic increase in their use, e.g. in Bangladesh (Giller et al. 2004).
There are two types of innovations: some you can try alone and others need to be adopted by a network. A solitary person can plant a new crop variety, for example, but it takes many people to start using super granules. Â A manufacturer has to build the briquetting machines. A second manufacturer has to buy a briquetting machine, make the super granules and sell them. Extensionists have to teach farmers how to place the super granules in the rice field. Then the farmers have to use the super granules, and make the idea their own.
It is kind of a chicken and egg problem. Farmers can’t use the super granules until someone makes them. Nobody will make them if there are no customers.
A step in the right direction is to show farmers the value of the super granules. The IFDC (International Fertilizer Development Center) commissioned Agro-Insight to make a farmer learning video on how to use urea deep placement. The video was filmed in West Africa, but the concepts also apply to Asia or even Latin America.
Of the 80 million hectares of irrigated rice worldwide, two million are in Latin America and the Caribbean, where 800,000 smallholders make their livings growing rice: 59% of which is irrigated (i.e. appropriate for urea super granules). And the region has the most potential of any to expand irrigated rice production. Rice is a popular food; tropical Latin Americans eat an average of 37 kilos of milled rice every ear, equivalent to a generous portion of 1.3 cups of cooked rice per day. As incomes increase, Latin Americans eat (and import) more rice.
As Latin America and the Caribbean grow more rice, it will help to make better use of nitrogen. So the urea deep placement video was recently translated to Spanish (there was already a Portuguese version). The video is a start, as it can teach farmers and extensionists about the importance of using fertilizer more efficiently, so that farmers can start to demand super granules and encourage companies to make and stock them. Even without super granules, growers of any crop will harvest more and save money if they grasp the idea that urea goes further if it is buried in the soil. This innovation makes a small contribution towards solving the problem of global warming.
Bent, Elizabeth 2015 The ground exhales: reducing agricultureâs greenhouse gas emissions http://theconversation.com/the-ground-exhales-reducing-agricultures-greenhouse-gas-emissions-40795
Giller, Ken E., Phil Chalk, Achim Dobermann, Larry Hammond, Patrick Heffer, Jagdish K. Ladha, Phibion Nyamudeza, Luc Maene, Henry Ssali, and John Freney 2004 âEmerging Technologies to Increase the Efficiency of Use of Fertilizer Nitrogen,” pp. 35-51. In Arvin R. Mosier, J. Keith syers and John r. Freney (Eds.) Agriculture and the Nitrogen Cycle: Assessing the Impacts of Fertilizer Use in Food Production and the Environment. Washington: Island Press.
Pulver, Eduard 2010 âManejo EstratÃ©gico y ProducciÃ³n Competetiva del Arroz bajo Riego en AmÃ©rica Latina,â pp. 350-362. In VÃctor Degiovanni B., CÃ©sar P. MartÃnez R., & Francisco Motta O. ProducciÃ³n Eco-Eficiente del Arroz en AmÃ©rica Latina. Volume 1. Cali, Colombia: CIAT. http://ciat-library.ciat.cgiar.org/Articulos_Ciat/2010_Degiovanni-Produccion_eco-eficiente_del_arroz.pdf
Savant, N. K. and P. J. Stangel 1990 âDeep Placement of Urea Supergranules in Transplanted Rice: Principles and Practices.â Nutrient Cycling in Agroecosystems 25(1):1-83