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One of the problems for fresh fruit production in citrus plantations is pest occurrence, e.g. Phyllocnistis citrella Stainton (Lepidoptera: Gracillaridae) detected in Cuba in 1993. It has been considered as one of the most harmful pests of this crop due to the damages caused by larvae in the leaves, sprouts and fruits. To known the dispersion tendency of P. citrella is of so much interest for taking samples and the sampling method. The study was carried out in the Isla de la Juventud nursery on Rugoso, Carrizo and Troyer patterns, from June 1996 to February 1997. Samplings took place weekly in 30 plants previously fixed at random until the they were grafted. A vegetative sprout was taken and the development state and total population of P. citrella were quantified in the pattern studied. Data were evaluated according to Taylor's power law. Results showed that P. citrella distribution pattern was aggregated for the three patterns studied. Variability was found for development state of the insect in the space distribution pattern since eggs and larvae showed aggregation and pupae showed uniform dispersion. This result constitutes a premise to use a good sampling method of P. citrella in the citrus cultivation of Isla de la Juventud. [ABSTRACT FROM AUTHOR]

En un suelo ácido, a 1.100 msnm, se sembraron semillas de dos patrones de cítricos Citrus reshni y C. jambhiri conservadas en dos temperaturas 8 .10 0C y ambiente, almacenadas por diferentes tiempos. Plántulas de estos patrones se inocularon, al momento del trasplante a bolsas, con cepas micorrizógenas en suelo natural y suelo desinfestado. Se estableció una relación entre área foliar y el producto largo máximo por ancho máximo de las hojas. Con 30 días de almacenamiento se obtuvo el mayor porcentaje de emergencia, en temperaturas de 8-10° C se conservó más la semilla. En C. reshni las especies Acaulospora longulata + Entrophospora colombiana superaron a Glomus manihotis y al testigo en los dos tipos de suelo; en C. jambhiri en suelo natural la inoculación fue efectiva. Se encontraron coeficientes de determinación R2 mayores de 99% para ecuaciones de regresión lineal entre área foliar y largo x ancho de las hojas, y con muestras pequeñas se pudo estimar con exactitud el área foliar de patrones de cítricos en estado de vivero.Seeds of two citrus partners, Citrus reshni and C. jambhiri, preserved under two different temperatures-environmental temperature and temperature from 80 to 10 C were planted in an acid soil at 1.100 meters above sea level. In transplanting to bags, seedlings of these partners were inoculated with micorrhizal strains in a natural soil and in non-infected soil. A relationship among foliar area and the maximen length product by the maximum width in the leaves was established. The greatest emergency percentage was obtained during thirty days of storage; at temperatures from 8° to 10°C, the seed was better preserved. In C. reshni species Acaulospora longulata +Entrophospora colombiana exceeded Glomus manihotis and the control in both types of soil, in C. jambhiri in natural soil inoculation was effective. R2 over 99 % were found for linear regression among the foliar area and the length and width of the leaves. The accurate foliar area in Citrus partners in their first stages of growth was estimated through small samples.

At the C.N.I.-I.C.A. Palmira, fruit trees program the influence of "Tabog" Swinglea glutinosa was evaluated as rootstock for acid lime "Tahiti" Citrus aurantifolia, taking into account the following aspects: development and productivility of the trees quality and growth of fruits, demands of nutriments, and resistance or susceptibility to pest and disease; comparing its behavior with the commercial rootstocks rough, lemon C. jambhiri and mandarina, "Cleopatra" C. reticulata.En el C.N.l. Palmira del Instituto Colombiano Agropecuario (lCA), se evaluó la influencia del "Tabog" Swinglea glutinosa como porta-injerto para la lima "Tahiti " Citrus aurantifolia, teniendo en cuenta los siguientes aspectos: desarrollo y productividad del árbol, calidad y desarrollo de los frutos, exigencias de nutrimentos, resistencia o susceptibilidad a plagas y enfermedades; comparando su comportamiento con los porta-injertos comerciales limón "Rugoso" C. jambhiri y la mandarina "Cleopatra " C. reticulata.