WHO WE ARE SERVICES RESOURCES




Most recent stories ›
AgroInsight RSS feed
Blog

Finding solutions May 28th, 2017 by

Farmers may doubt the worth of an innovation, until they meet other people who have tried the idea on their own land. In 2015, the village of Korelach in West Pokot, Kenya, was suffering. The land was so eroded and degraded that it was getting difficult to raise crops. Many people were leaving the community. Then they got some help from researchers at the nearby University of Eldoret, who were looking for a community with challenging soil erosion problems. The researchers soon realized that the immediate culprit was sand extraction. Brokers from the city would come and load a lorry with sand in the dry river bed. A crew of local men could earn 3000 shillings ($30) for shoveling the truck full of sand, but no other villagers benefited. The sand would be sold in nearby cities for up to 60,000 shillings ($600), to use for construction.

carrying pale of water on headAs more sand was extracted, the dry river bed became a gully so deep that people could hardly walk to the other side of it. It was getting increasingly difficult to cross the river to farm or visit neighbors. When the researchers explained to the villagers how much the brokers were earning from the sand, the villagers said “We cannot let this gully hold us off; we need to hold on to it and fight it off.”

The villagers banded together and stopped the sand digging. With the next rainy season, the pits in the riverbed began to fill up with sand. The gully became easier to cross, and the riverbank stabilized. A minister from a church in Korelach convinced the local government to drill a well (a borehole) on the river bank, where women could pump their own water close to home, and avoid long walks to fetch water.

This success created enough trust for the researchers to propose new soil and water conservation techniques for the village. In May, 2016 the university took five farmers from Korelach to Tigray, Ethiopia, to learn about the new techniques. However, the results were disappointing: in part because the Kenyan farmers had to speak to their Ethiopian peers through interpreters, but also because the expense of international travel meant that the project could only take a few Kenyan farmers.

On their return, the five farmers were unable to convince the rest of the community to try the new techniques. The other villages had not been to Ethiopia, and were still skeptical that the land could be improved with simple techniques.

Then in December 2016, the researchers tried a different tactic. They took a whole bus load of farmers from Korelach to Machakos, on the other side of Kenya. This had several advantages, explained Professor Wilson Ng’etich of the University of Eldoret. First, the bus could hold more people, so women and youth were able to go on the trip, while only senior men had been to Ethiopia. Second, most Kenyans speak Kiswahili in addition to their local language, so the farmers from Korelach could speak freely to farmers in Machakos.

The farmers from Korelach were impressed with what they saw: “Those guys in Machakos have worse land than us, but they are taking better care of it than we are.”

After the visit, researchers were able to help the people of Korelach set up their own experiments with soil and water conservation, such as small, hand-made earthen “sand dams” to slow the rain runoff, so water would soak into the soil instead of washing it away. The farmers also tried cover crops, such as legumes that build soil fertility by fixing nitrogen and leaving biomass on the soil.

Now Korelach is ready to try other ideas, such as planting fruit trees and multi-purpose legumes (that not only enrich the soil, but also feed people).

“We didn’t want to be the solution bringers. We wanted to strengthen the idea that villagers can solve their own problems,” explained Dr. Syphylline Kebeney of the University of Eldoret.

The farmers are also starting to get a more positive vision of the future. One farmer could imagine her fruit trees so vividly that she said “I’m seeing myself with a gunny bag full of mangos on my back going to market.”

This experience shows that cross-site visits can spark farmers’ interest to overcome their own discouragement, engage in collaborative research and see a different future for their land.

Acknowledgement

The work in Korelach was sponsored by the Collaborative Crop Research Program (CCRP) of the McKnight Foundation.

Further reading

Watching other farmers on a video can often be as convincing as a meeting in real life, as we have seen in some earlier stories.

Call anytime

Stop erosion

Friends you can trust

New crops for Mr. Mpinda

Share on FacebookTweet about this on Twitter

What do earthworms want? April 16th, 2017 by

Vea la versión en español a continuación

Even seemingly simple tasks, like raising the humble earthworm, can be done in more ways than one, however all variations must follow certain basic principles.

In a video from Bangladesh, villagers show the audience how to raise earthworms in cement rings, sunk into the soil. The floor is covered with a sheet of plastic to keep the worms from escaping. The worms are fed on chunks of banana corm and the ring is covered to keep out the rain, but still retain some moisture.

My grandfather used to raise worms in a pressed-board box on his back porch. He fed them on strips of newspaper and used coffee grounds. So I knew that there was more than one way to raise worms, but I didn’t quite realize how many options there were, until I saw two small, family firms in Cochabamba, Bolivia this week at an agricultural fair. Both firms raise earthworms and sell the worms, the humus they make, and the excess moisture collected in the process (to use as fertilizer—applied on leaves or the soil).

mitt full of earthwormsOne company, Biodel, experimented with various types of containers. The worms died in plastic ones, but they thrived inside of aluminum cylinders, wrapped in foam (to keep them cool) inside of a metal barrel. A screened base with a tray collects the humus, while worm food (especially composted cow manure) is loaded into the top of the barrel.

worm rackA second company, Lombriflor, had a different devise. They use stacks of plastic-covered wooden trays on a slight slant, and they feed the earthworms corn plant residues, semi-composed cow manure, and kitchen scraps. Earthworms have their favorite foods. “Earthworms like all of the cucurbits (like squash), but nothing sour,” explained Silvio Gutiérrez and his wife, the company owners. “They don’t like citrus at all.” Earthworms will eat paper, but they prefer egg cartons.

So here we have a Bangladeshi cement ring, a Bolivian barrel and a set of wooden trays. It seems like a lot of different ways to raise worms, which is an important topic, because the night-crawlers, as my grandfather used to call them, help to enrich the compost, stabilize it and they improve the soil with the beneficial micro-organisms they release.

All of these worm brooders share certain core principles. The worms are kept cool, not allowed to escape, and are fed on organic matter (depending on what is abundant locally) and the earthworms are not allowed to get too dry or too moist.

The Bangladeshi earthworm video has been translated into Spanish and will soon be released in Bolivia. We hope it will inspire smallholder farmers to invent additional devices for raising the under-rated earthworm.

The Access Agriculture video-sharing platform will soon also host yet another video about rearing worms, featuring rural entrepreneurs in India who use woven polythene bags as containers.

Watch the video

The wonder of earthworms

¿QUÉ QUIEREN LAS LOMBRICES DE TIERRA?

Por Jeff Bentley, 16 de abril del 2017

Hasta tareas aparentemente sencillas como criar a la humilde lombriz de tierra, pueden hacerse en más de una forma, aunque todas las variantes deben seguir ciertos principios básicos.

En un video de Bangladesh, los aldeanos muestran a la audiencia cómo criar las lombrices de tierra en argollas de cemento, semi-enterrados en el suelo. El piso se cubre con una hoja de plástico, para que las lombrices no escapen. Las lombrices comen pedacitos de tallos de plátano y la argolla se cubre, para que las lombrices no se ahoguen con la lluvia, pero que no se resequen tampoco.

Mi abuelo solía criar lombrices en una caja de tablas de aserrín prensado en el corredor de su casa. Les alimentaba con tiras de periódico y borras de café. Así que yo ya sabía de más de una manera de criar lombrices, pero no me di cuenta de cuántas opciones había, hasta ver dos pequeñas empresas familiares en Cochabamba, Bolivia esta semana en una feria agrícola. Ambas empresas crían lombrices y las venden junto con el humus que hacen y el líquido que se recolecta en el proceso (para usar como fertilizante—aplicado a las hojas o al suelo).

mitt full of earthwormsUna empresa, Biodel, experimentó con varias clases de contenedores. Las lombrices se morían en los de plástico, pero prosperaban en los cilindros de aluminio, forrados en espuma (para mantener la frescura) dentro de un barril metálico. Una base de malla con una charola recolecta el humus, mientras la comida de lombrices (especialmente estiércol de vaca compostada) se pone a la parte superior del barril.

worm rackUna segunda compañía, Lombriflor, tiene otro dispositivo. Ellos usan bandejas de madera, una encima de la otra, livianamente inclinadas y cubiertas de plástico, y alimentan a las lombrices con residuos de plantas de maíz, estiércol de vaca semi-compostada, y restos de cocina. Las lombrices tienen sus comidas favoritas. “A las lombrices les gustan todas las cucúrbitas (como el zapallo), pero nada ácido,” explicó Silvio Gutiérrez y su esposa, los dueños de la empresa. “No les gustan los cítricos para nada.” Las lombrices comerán papel, pero prefieren maples de huevo.

Así que tenemos una argolla de cemento bangladesí, un barril boliviano y un juego de bandejas de madera. Parecen muchas maneras para criar lombrices, lo cual es un tema importante, porque las lombrices ayudan a enriquecer el compost, estabilizarlo y mejoran el suelo con los micro-organismos benéficos que liberan.

Todos estos criaderos de lombrices comparten ciertos principios de fondo. Las lombrices se mantienen frescas, no pueden escapar, y se les alimenta con materia orgánica (lo que esté localmente abundante) y a las lombrices no se les deja mojarse mucho ni secarse demasiado.

El video de Bangladesh sobre la lombriz de tierra se ha traducido al español y pronto será distribuido en Bolivia. Esperamos que ello inspire a muchos campesinos a inventar otras herramientas adicionales para criar a la subestimada lombriz.

La plataforma para compartir videos, Access Agriculture, pronto albergará otro video sobre la crianza de lombrices de tierra, presentando a empresarios rurales en la India quienes usan gangochos (sacos de yute plástico) como sus contenedores.

Ver el video

La maravillosa lombriz de tierra

Share on FacebookTweet about this on Twitter

Chemical attitude adjustment February 26th, 2017 by

Kannappan, C. Sekar, his wife, Bharathidasan, BagyarajAgricultural extension can work deep changes in farmers’ attitudes. Ironically, the extensionists themselves often think that a change in heart is difficult to achieve, so it was good to meet some inspired farmers last week in Tamil Nadu, India, while teaching a course with Paul Van Mele to agricultural researchers and extension agents.

We wrote four fact sheets with advice for farmers and we wanted to show the papers to real farmers, as a kind of peer review. One of the participants, Mrs. P. Tamilselvi, took us to the village of Seethapappi, where she works as an extensionist. The course participants, mostly agricultural researchers, formed small groups and found farmers to talk to.

We approached a farmhouse, where entomologist K. Bharathidasan called out, asking if anyone was home. When a surprised couple emerged, Bharathidasan introduced himself and soon had the farmers reading a fact sheet in Tamil on groundnut stem rot.

After Mr. C. Sekar read the fact sheet he talked about an organic agricultural concoction he used as a fertilizer and insecticide. He called it pancha kaviya, alluding to five ingredients it contained. Bharathidasan wrote down the recipe:

Mix 1) cow dung, 2) cow urine, 3) ghee, milk and curd, 4) coconut water and 5) jiggery (a candy) or sugarcane juice. Mix the ingredients thoroughly. Keep for 45 days. Filter the liquid directly into a sprayer and spray the crop.

This was only the first of many natural agro-chemicals farmers in this village described to us. Sekar also makes an organic pesticide with eight types of local plants. He adds them to cow urine and keeps them for 20 days. Then he filters the liquid and sprays it on his crops.

When Mrs. Sekar read the fact sheet she mentioned another organic pesticide. Two more farmers had their own recipe for a home brew to spray on plants.

Bagyaraj and farmer Prakash Kanna CROPPEDFarmer Prakash Kanna showed us a batch of pancha kaviya he’d made, a dull brown mix in a plastic drum. It had a strong, sour smell. He put it in irrigation water to fertilize his plants. He called it a growth regulator. (The pancha kaviya adds nutrients and beneficial flora and fauna to the soil).

The farmers said they also used marigold extract and gypsum powder to control various diseases in groundnuts (peanuts). And they enhance the soil with a beneficial bacterium, Pseudomonas, mixed with aged cow dung which helps the bacteria multiply and suppress fungi that cause disease.

That’s quite a lot of innovation.

Bharathidasan later told me that the farmers really liked the fact sheets, except for the references to chemicals. That wasn’t surprising given the many non-chemical options the villagers were using.

Later that week we visited another village, Panayaburam, slightly larger than Seethapappi, with a small cooperative office where the farmers met.

Here we quickly learned of a different set of attitudes. The farmers did mention neem oil and using a net to keep small insect pests out of vegetables, but many said that “here we only use chemicals.” One went so far as to say that if you used a mix made from cow dung on your plants, the other farmers would say that you were insane.

Anthropologists have long known that each village is unique; conclusions drawn in one village may not apply to neighboring ones. Even so, such a big difference in attitudes to chemicals was surprising. Seethapappi farmers said that they liked everything in the fact sheets, except for the chemicals. In Panayaburam farmers only wanted to know about pesticides to manage pests and diseases.

There is one major difference between these two villages. Organic-leaning Seethapappi has a KVK (farm science center), where farmers receive training and get advice. Extension agents in that KVK have generated a lot of excitement about making inputs from local materials. Panayaburam does not have a KVK, and farmers rely on the biased advice of agro-chemical dealers to keep plants healthy.

A KVK is a permanent structure, with a building and staff, working with farmers over the years. Extensionists may become frustrated with the pace of change because farmers seldom adopt a new technique instantly. Smallholders have to try out innovations on their own. Extension agents can and do make a difference in farmers’ attitudes about agrochemicals, even if it takes time.

Share on FacebookTweet about this on Twitter

Crop with an attitude January 29th, 2017 by

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 “tarwi”, from Quechua, the language of the Incas.

tarwi in bloomWhile making a video in Bolivia, my colleagues and I asked doña 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. That’s 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 don’t 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. “Yes, and it does very well. Planting tarwi is like fallowing your soil, or like using chicken manure,” he explained.

Tarwi seeds are also rich in oils and proteins and doña Eleuteria regularly feeds lupin beans to her children. Like some other Bolivians doña Eleuteria make a nutritious snack by boiling the seeds, but it’s 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.

sorting tarwi or lupine seedWhile visiting doña 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 doña 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.

“I do bury them,” she explained, “because they are so bitter that if the chickens eat them they will die.”

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.

Acknowledgements

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.

Further reading

Calisaya, J.J.,  M. Lazarte, R. Oros, P. Mamani 2016 “Desarrollo Participativo de Innovaciones Tecnológicas para Incrementar la Productividad de los Suelos Agrícolas en Regiones Andinas Deprimidas de Bolivia.” Read at the Community of Practice meeting, McKnight Foundation, Ibarra, Ecuador 11-16 July. See the paper here.

Further viewing

The farmer training video Growing lupine without disease can be viewed and downloaded on the Access Agriculture video-sharing platform in English, French, Spanish, and shortly also in Quechua and Aymara.

CULTIVO CON CARÁCTER FUERTE

Por Jeff Bentley

29 de enero del 2017

Una planta tiene una personalidad, y como la gente y los países, algunos tienen más carácter 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 países. En Bolivia se llama “tarwi”, del quechua, el idioma de los Incas.

Mientas mis colegas y yo filmábamos un video en Bolivia, pedimos que doña Eleuteria en la comunidad de Phinquina nos contara qué sembraba después de cosechar el tarwi. Ella nos sorprendió cuando dijo que a veces sembraba papa después del tarwi. Es increíble, porque las papas son tan exigentes que muchos agricultores andinos descansan el suelo durante años antes de sembrar papas. Si no, el suelo tendrá 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 pregunté a Reynaldo Herbas de la comunidad de Tijraska, si él jamás había sembrado papas después del tarwi. “Sí, y produce muy bien. El sembrar tarwi es como descansar sus suelo, o como usar gallinaza,” explicó.

Marcella films Eleuteria soaking tarwiLos granos de tarwi son ricos en aceites y proteínas y doña Eleuteria a menudo los da de comer a sus hijos. Igual que algunas otras bolivianas, doña Eleuteria hace una merienda nutritiva con los granos cocidos, pero cuesta mucho trabajo. Los granos tienen que remojarse en agua durante tres días antes de cocerse, para después dejarlos en el chorro del río durante varios días más para expulsar los amargos alcaloides.

El Ing. Agrónomo Juan Vallejos de Proinpa (un instituto de investigación) confirmó que el tarwi toma mucha agua para procesarse. Es irónico, porque el tarwi se recomienda para zonas secas con suelos empobrecidos. Existen variedades dulces, sin los alcaloides amargos, pero en Bolivia recién empieza la búsqueda por esos lupinos dulces.

Cuando visitamos a doña Eleuteria para aprender cómo ella procesa la semilla, nos mostró cómo quitar los granos malos de tarwi, para asegurarse que el cultivo que siembra será sano. (La enfermedad principal es la antracnosis, causada por el hongo Colletotrichum gloeosporioides). Preguntamos a doña Eleuteria qué hacía con los granos enfermos. Pensábamos que diría 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 tóxicos, bien sea sanos o enfermos.

Eleuteria Sanchez burries bad lupine seed as chicken will die if they eat it“Los entierro,” explicó, “porque son tan amargos que si las gallinas se los comen podrían morirse.”

El Ing. Vallejos explicó que las plantas de tarwi están 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 sequía 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 adaptación al cambio climático.

Una planta puede tener una personalidad compleja, con cualidades de oro igual que algunos defectos trágicos. El tarwi o lupino en muchas maneras en el cultivo perfecto: bien adaptado a los desafíos 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.

Agradecimientos

Para escribir este cuento en Cochabamba, Bolivia, tuve la buena suerte de estar acompañado de Paul Van Mele y Marcella Vrolijks de Agro-Insight y Juan Vallejos y Maura Lazarte y otros de Proinpa. La visita se financió por la McKnight Foundation.

Para leer más

Calisaya, J.J.,  M. Lazarte, R. Oros, P. Mamani 2016 “Desarrollo Participativo de Innovaciones Tecnológicas para Incrementar la Productividad de los Suelos Agrícolas en Regiones Andinas Deprimidas de Bolivia.” Trabajo presentado en la reunión de la Comunidad de Práctica, McKnight Foundation, Ibarra, Ecuador 11-16 de julio. Ver la presentación aquí.

Para ver más

El video educativo para agricultores Producir tarwi sin enfermedad está disponible para ver y bajar en inglés, francés, español, y pronto también en quechua y aymara, en la plataforma Access Agriculture que se dedica a compartir videos.

Share on FacebookTweet about this on Twitter

Deeper nitrogen, more rice, a cooler planet December 25th, 2016 by

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 “urea deep placement” makes much better use of nitrogen.

usgUrea 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 “super granules” of urea into the soft soil, between four rice plants. This deep placement puts the urea underground, near the plants’ 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.

usg-bricketing-machineThe 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.  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).

urea-usg-granule-plantingThere 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.  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.

urea-granule-plantingA 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.

Further viewing

You can watch the urea deep placement video in English here, in Spanish here, and in nearly 30 other languages here.

Related blog

Take a stab

Further reading

Bent, Elizabeth 2015 The ground exhales: reducing agriculture’s 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 “Emerging 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 “Manejo Estratégico y Producción Competetiva del Arroz bajo Riego en América Latina,” pp. 350-362. In Víctor Degiovanni B., César P. Martínez R., & Francisco Motta O. Producción Eco-Eficiente del Arroz en América Latina. Volume 1. Cali, Colombia: CIAT. http://ciat-library.ciat.cgiar.org/Articulos_Ciat/2010_Degiovanni-Produccion_eco-eficiente_del_arroz.pdf

Ricepedia http://ricepedia.org

Savant, N. K. and P. J. Stangel 1990 “Deep Placement of Urea Supergranules in Transplanted Rice: Principles and Practices.” Nutrient Cycling in Agroecosystems 25(1):1-83

 

 

Share on FacebookTweet about this on Twitter

Design by Olean webdesign