Aplicación del método STATIS-ACT al régimen de lluvias en la Región Oriental Venezolana

Rainfall analysis is one of the most im­portant tools to understand the spatial natural phenomena behavior. Our goal was to describe the rainfall patterns using fourteen variables derived from descriptive statistics of sixty-five climatic stations in the eastern of Venezuela using the STATIS-ACT method. The analysis gener­ated four coherent groups of precipitation consisting of meteorological stations with a specific pattern of precipitation. Groups 1 and 3 have presented greater interannual variability. On the other hand, increased rainfall stations are represented by Groups 2 and 4. In addition, the lat­ter group has had greater stability in rainfall variability between years due to the lower levels of the coefficient of variation. The study showed precipitation patterns associated with units landscapes of eastern char­acteristics that could be used in agricultural planning long term.  El análisis de la precipitación es de suma importancia para poder comprender el comportamiento de fenómenos naturales que varían espacialmente, representando una herramienta útil para tomar decisiones en el ámbito agrícola. El objetivo del estudio fue caracterizar el régimen de lluvia usando catorce variables originales de la precipita­ción mensual de sesenta y cinco estaciones climáticas ubicadas en la región oriental de Venezuela, aplicando la metodología STATIS-ACT. El análisis generó cuatro grupos coherentes de precipitación constituidos por estaciones meteorológicas, con un patrón de precipitación especí­fico. Los grupos 1 y 3 han presentado mayor variabilidad interanual. Por otro lado, las estaciones de mayores lluvias están representadas por los Grupo 2 y 4. Además, este último grupo, ha tenido una mayor estabili­dad en la variabilidad pluviométrica entre años debido a los menores niveles del coeficiente de variación. El estudio evidencia patrones de precipitación asociadas a las unidades de paisajes características de la región oriental que pudiera ser utilizado en la planificación agrícola a largo plazo

simple and low-cost strategy for micropropagation of cassava (Manihot esculenta Crantz)

With the aim of transferring micropropagation techniques to cassava seed producers, a simple and lowcost medium for in vitro micropropagation was developed. CM6740-7 cassava cultivar from CIAT was used as planting material. Commercially available nutrients were used in order to substitute the propagation media components. A Hydro Agri´s fertilizer (12-11-18/3 (MgO-EDTA)) was used as a substitute for Murashige and Skoog macro and micronutrients. Additionally, table sugar and molasses were used as a source of carbohydrates and vitamins. Radixone 3AS from Praquim C.A. was used as a source of auxins and activol as a source of gibberellic acid. Numbers of roots and leaves, height and dry weight of plantlets was determined for each treatment and compared with a conventional micropropagation media. For all the parameter measured, the plantlets obtained on the fully substituted media showed a good growth performance. Canonical biplot analysis showed that this media was especially good for the number of nodes (multiplication rate) in 60-day-old cultured plants. The designed medium is simple, easy to prepare and allows a low-cost strategy to obtain a high quality in vitro micropropagated cassava plants and its ready availability may have an impact on the production of planting material of cassava