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For 13 cucumber genotypes grown under greenhouse conditions the researchers quantified relations among seven variables: fruit length (FL, in cm), fruit diameter (FD, in mm), fruit weight (FW, in g), number of fruits per plant (NFP), yield (Y, in kg/plant), percentage of total soluble solids (TSS, in °Brix), and days to start of harvest (DSH, in days after transplant-dat). Also, path analysis was estimated for yield. The crop was planted on coconut fiber as substrate, and managed with fertigation. Yield showed a highly significant correlation with FD (r = -0.75**) and NFP (r = 0.59**). The main positive direct effects on yield were exhibited by FW (path coefficient-PC = 1.66), NFP (PC = 1.18) and DSH (PC = 0.28), while maximum positive indirect effects on yield were exhibited by FL (PC = 1.63), DSH (PC = 1.01), FD (PC = 0.65) and TSS (PC = 0.65) through FW; and by NFP (PC = 0.61) through FL. On the other hand, the main negative direct effects on yield were exhibited by FL (PC = -0.78), TSS (PC = -0.23) and FD (PC = -0.17). It is concluded that FW and NFP were the main yield contributing variables in these trials, and thus represents fundamental selection criteria for greenhouse cucumber breeding. [ABSTRACT FROM AUTHOR]

The objective of this investigation was to evaluate the physical, chemical and biological soil properties of the soil in four crops systems in a typical agroecosystem mountain conditions, on a farm in conversion to ecological production in the Massif Guamuhaya, Cuba, where predominant red ferrous soil leachate. We worked with a completely randomized design of four replicates and four treatments consisting Coffee Systems crops, pine, various crops (grains, tubers and vegetables) and vegetation transition to natural forest. The following variables were valued: Factor structure, stable aggregates in water, pH, phosphorus, potassium, organic matter, mesofauna and macrofauna. The soil devoted to coffee showed the best physical properties no difference with the transition to natural forest; although it had low levels of phosphorus, potassium and organic matter. , demonstrating a relatively high level in the indicators of biodiversity of the macro and mesofauna, while that of transition toward the natural forest manifested the best properties. The soil devoted to various crops, said intermediate properties relative to the rest while the pine, the highest level of organic matter but with deterioration of other properties. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Entomología is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Colombiana de Entomología is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

New precision agriculture technologies allow collecting information from several variables at many georeferenced locations within crop fields. The spatial covariation of soil properties and crop yield data can be evaluated by principal component analysis (PCA). Nevertheless, PCA has not been explicitly developed for spatial data as other multivariate descriptive methods. Other multivariate techniques that include spatial autocorrelation among data of neighborhood sites have been recently developed. In this paper, we apply and compare two multivariate analyses, PCA and spatially constrained multivariate analysis methods (MULTISPATI-PCA). The latter incorporates the spatial information into multivariate analysis calculating Moran's index between the data at one location and the mean values of its neighbors. The results showed that MULTISPATI-PCA detected relations in the data that were not detected with PCA. The mapping of spatial variability from the first principal component was similar between PCA and MULTISPATI-PCA, but maps from the second component were different due to the variance correction by spatial autocorrelation. MULTISPATI- PCA method represents a crucial tool to map spatial variability within a field, and to identify homogeneous zones in a multivariate sense. [ABSTRACT FROM AUTHOR]

Genetic diversity of the maize populations in Mexico is very dynamic and depends on biological, agroecological, and socio-economic factors and familiar needs. In this study, the morphological variability of a collection of 60 population samples of maize were described and classified, such samples were collected in 44 communities from Low Mixtec-Oaxaca region (846 masl to 1842 masl). The samples were sown and cultivated during crop cycle Spring-Summer 2010 at Santo Domingo Tonala, Oaxaca, under a randomized complete design with four replications. Nineteen morphological traits of plant, ear, kernel and tassel were evaluated and significant differences among maize populations were determined in these characters. The traits height plant and ear, number of kernels per row were determinants to describe the total morphological variability. Morphological and phenological variation of the maize populations was associated with patterns of altitudinal and geographic variation of the sample origin. Six phenotypic groups with significant differences among them but with similar ear, kernel and plant traits to describes for races Celaya, Bolita, Pepitilla, Ancho and some racial complexes among Ancho, Mixteco, Celaya and Bolita. [ABSTRACT FROM AUTHOR]

Crop coefficients (Kc) of apple trees 'Cripp's Pink', during the second growing season, were determined at EEA INTA Alto Valle. Individual trees were placed in each of three lysimeters; at the time of orchard establishment. The trees were watered every day by drip irrigation with emitters delivering 4 l h-1, placed every 0.50 m. During the growing season the following determinations were performed: water volume applied and drained, soil water tension, trunk sectional area, intercepted photosynthetic radiation and percentage of shaded surface. Maximum monthly crop water evapotranspiration (ETc) was in January, reaching 2.5 mm day-1<. This was equivalent to 20 liters per tree day-1, taking into account the planting square. The Crop coefficients increased from 0.26 at full bloom (04/10/09) to 0.47 in the final of November and from there they remained almost constant until the end of April. Annual evapotranspiración for apple tree 'Cripps's Pink', during the second growing season, was 401 mm. [ABSTRACT FROM AUTHOR]

The objective of this work was to study the physico-chemical and biological properties of two surface soils fertilized with nitrogen and organic amendment in the Upper Rio Negro Valley (orchards H1 and H2). In both orchards, nitrogen fertilizer was applied during the 2008-2009 and 2009-2010 seasons and on H2 chicken manure was applied. Soil samples were collected in spring and autumn and determined: total organic carbon, electrical conductivity, exchangeable cations, sodium adsorption ratio and nitrate, microbial respiration, microbial biomass carbon, dehydrogenase activity and the rate of mineralization. The concentration of total organic carbon, nitrogen and potassium were suitable for the production of pears. The behavior of biological variables was different in the orchards. In orchard H1 were higher in spring, in both seasons, and the mineralization rate was slightly higher than 1 in autumn, indicating some balance between mineralization and humification of carbon. In H2 biological measurements were similar between seasons as a result of making nitrogen (N) fertilization in spring and autumn. The organic amendment did not increase the biological activity in the spring. Microbial and enzymatic activities in H1 and H2 were sensitive to changes occurring in soils. [ABSTRACT FROM AUTHOR]

The work is based on a research project done by Research on Agriculture and Food Product Center (CITMA).The research was done along with a group to better genetic production of sunflower seed at the Research for Food Investigation at Villa Clara province's Martha Abreu Central University, (UCLV) The goal was to creat strategy to produce sunflower seed for Villa Clara's province as an alternative to food production, on land previously used for sugar cane production. In accordance with the characteristics of sunflower seed production, its insertion is possible in the production system as an alternative. Because of the importance of contributing to the diversification of eating products, elevating the technical level and increasing its yielding, one concludes that a strategy with a questionnaire given to Villa Clara producers to apply this theory, considerable success has been had in the production of sunflower seeds without precedence in Villa Clara province. [ABSTRACT FROM AUTHOR]

El artículo se enfoca en la evaluación del incremento de la población de insectos enemigos naturales en el Huerto de Manacas, Villa Clara, Cuba entre los años 2006 y 2008. Según los autores, se contribuye el incremento de los insectos a los cambios en la administración de los cultivos y de las plagas debido al aumento de la biodiversidad de vegetación en los campos de cultivos. La diversidad de artrópodos con la vegetación contribuyó al aumento de los insectos.

El artículo enfoca en el estudio de la asociación de cultivos en las plantaciones de bananos y su efecto en el suelo. El estudio se llevó a cabo entre los años 2002 y 2004 en un suelo pardo con carbonatos, junto con los cultivos de maní, habichuela, maíz y boniato. Según los autores, los resultados indicaron que los cultivos asociados no afectaron al suelo de manera negativa.

Se presentan los resultados de un estudio sobre los síntomas ocasionados por el hongo Alternaria solani Sor. en cultivos de tomate. Se evaluó el híbrido HA-3019 (de la firma israelí Hazera) entre agosto y noviembre de 2004 con diversas condiciones de sombra. Los resultados sugieren la regulación de la sombra y la aplicación de fungicidas.