Se presenta informacion preliminar acerca del proceso y las causas de sucesion de sabanas de Trachypogon vestitus y de Paspalum pectinatum despues de quema y pastoreo, en Carimagua, Colombia. En varios expt. en los cuales se aplicaron diferentes tasas de carga a parcelas con y sin quema, se observo que la cobertura de plantas tendio a ser mayor en las parcelas con quema, a la mayor tasa de carga y al inicio y al final de la epoca seca. La quema y el pastoreo no afectaron el no. de plantas emergentes. Despues de la quema y con tasa de carga baja, T. vestitus predomino en la sabana de P.

Mediante un minisimulador de lluvia se evaluaron los cambios en pérdida de suelo y en algunas propiedades físicas asociadas con el movimiento del agua, en un Inceptisol (Dystric haplustepts) de la zona de reconversión del cultivo de trigo del departamento de Nariño, Colombia (75º 14Ž oeste, 0.5º 10Ž norte, 2.710 msnm, 79% HR, 12ºC). Los tratamientos fueron: Suelo no intervenido a 25% de pendiente (testigo), uso en pastura por 25 años, 25% de pendiente y uso agrícola rotación trigo-maíz (rt-m) de 25, 45 y 70 años de uso, cada uno de estos últimos a 12% y 25% de pendiente.

This audiotutorial unit (cassette, printed script, 70 color slides, study guide, self-evaluation test), prepared by the Communications Support Unit at CIAT, is available for use with a manually or automatically synchronized slide projector/cassette tape recorder. Each unit is available from the Distribution Office at a cost of US$ 50; photocopies of the study guide alone can be obtained from the Cassava Information Center. Data are given on the biology of the hornworm, its economic importance and possible methods of control.

Powerpoint presentation by the International Center for Tropical Agriculture (CIAT) about the ten key steps for "ELMO".

This audiotutorial unit (cassette, printed script, 124 color slides, study guide, self-evaluation test), prepared by the Communications Support Unit at CIAT, is available for use with a manually or automatically synchronized slide projector/cassette tape recorder. Each unit is available from the Distribution Office at a cost of US$$50; photocopies of the study guide alone can be obtained from the Bean Information Center.

Maize (Zea mays L.) and bean (Phaseolus vulgaris L.) are commonly grown in association in eastern and southern Africa. Results from 64-fertilizer response trials conducted in Kenya were used to study the relationship between maize monoculture response to fertilizer nitrogen and phosphorus and the intercrop response. The intercrop was more productive that the monoculture with no fertilizer applied, but overall responses of systems to applied nutrients did not differ. Maize, both in monoculture and intercropped, responded more frequently to applied N than did the intercropped bean.