Exploración de opciones agroecológicas en el sistema de milpa de la Costa Chica, México

Los sistemas de producción de la Costa Chica enfrentan serios problemas de degradación del suelo y baja productividad de maíz y jamaica. Esta situación demanda el diseño e implementación de alternativas agroecológicas para revertir esta problemática. Diversos protocolos experimentales que incluyeron opciones de fertilización e integración de leguminosas se desarrollaron en milpas de agricultores. Con base en los resultados encontrados se realizaron exploraciones a través de modelaje para evaluar el impacto de esas alternativas en el rendimiento de maíz y en el balance de materia orgánica a nivel sistema de producción. Los resultados demostraron que la integración de los componentes evaluados (fertilización, leguminosas y retención de residuos) tuvo efectos positivos en los ingresos familiares y en el balance de materia orgánica.Farming systems in Costa Chica, Mexico face problems related to soil degradation and low crop productivity. This situation requires designing and implementing agroecological alternatives to improve cropping systems. Several experimental trials that included fertilization and intercropping of legumes in current milpa systems were carried out in farmers´ fields. Based on the results modeling explorations were carried out to evaluate the impacts of these field-level agroecological options at farm level. The results showed that the integration of the evaluated components (fertilization, legumes and crop residues retention) had positive effects on family income and organic matter balances.Eje A1 Sistemas de producción de base agroecológica (Trabajos científicos)Facultad de Ciencias Agrarias y Forestale

DSMM XI study: dose definition for intravenous cyclophosphamide in combination with bortezomib/dexamethasone for remission induction in patients with newly diagnosed myeloma

A clinical trial was initiated to evaluate the recommended dose of cyclophosphamide in combination with bortezomib and dexamethasone as induction treatment before stem cell transplantation for younger patients with newly diagnosed multiple myeloma (MM). Thirty patients were treated with three 21-day cycles of bortezomib 1.3 mg/m2 on days 1, 4, 8, and 11 plus dexamethasone 40 mg on the day of bortezomib injection and the day after plus cyclophosphamide at 900, 1,200, or 1,500 mg/m2 on day 1. The maximum tolerated dose of cyclophosphamide was defined as 900 mg/m2. At this dose level, 92% of patients achieved at least a partial response. The overall response rate [complete response (CR) plus partial response (PR)] across all dose levels was 77%, with a 10% CR rate. No patient experienced progressive disease. The most frequent adverse events were hematological and gastrointestinal toxicities as well as neuropathy. The results suggest that bortezomib in combination with cyclophosphamide at 900 mg/m2 and dexamethasone is an effective induction treatment for patients with newly diagnosed MM that warrants further investigation

Characterization of host tolerance to Striga hermonthica

One of the most promising control options against the parasitic weed Striga hermonthica is the use of crop varieties that combine resistance with high levels of tolerance. The aim of this study was to clarify the relation between Striga infestation level, Striga infection level and relative yield loss of sorghum and to use this insight for exploring the options for a proper screening procedure for tolerance. In three pot experiments, conducted in Mali (2003) and The Netherlands (2003, 2004), four sorghum genotypes were exposed to a range of Striga infestation levels, ranging from 0.0625 to 16 seeds cm−3. Observations included regular Striga emergence counts and sorghum grain yield at maturity. There were significant genotype, infestation and genotype × infestation effects on sorghum yield. The relation between infestation level and infection level was density dependent. Furthermore, the relation between Striga infection level and relative yield loss was non-linear, though for the most resistant genotype Framida only the linear part of the relation was obtained, as even at high infestation levels only moderate infection levels were achieved. The results suggest that for resistant genotypes, tolerance can best be quantified as a reduced relative yield loss per aboveground Striga plant, whereas for less resistant genotypes the maximum relative yield loss can best be used. Whether both expressions of tolerance are interrelated could not be resolved. Complications of screening for tolerance under field conditions are discussed