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A new species of the monotypic endemic genus Omiltemia Standl. was discovered in the Sierra Madre Occidental at the western part of the state Oaxaca, near to the border of the state Guerrero. The small leaved new species ( O. parvifolia ) holding the main characteristics of the genus Omiltemia , the slightly asymmetrical tubular corolla and the broadly winged filaments inserted in the lower half of the corolla tube, just above of its narrow part, confirms the separation of the genus from Pseudomiltemia Borhidi. Key words: Mexico, new, Oaxaca, Omiltemia

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Estudios Sobre Rubiáceas Méxicanas XXXVI

Dos especies nuevas en el género Rogiera Planch. (Rondeletieae)

Acta Botanica Hungarica
Authors: A. Borhidi and K. Velasco Gutiérrez

Two new Rogiera species have been detected in the collections of the Andayu group of Oaxaca (R. oaxacensis) and of the State University of Tabasco (R. tabascensis). Both species are notable because of their pending, creeping, liana-like habit growing on calcareous rocks, which is a rare geological formation in the mountainous systems of México formed mostly by old crystalline cordilleras and young volcanic ridges. Up to now only one species of Rogiera, the R. subscandens from Chiapas and Guatemala has been known of this life-form.

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Two new species of the genus Deppea . Schltdl. et Cham. were collected in the Putla district of Oaxaca state, near to the Oaxaca-Guerrero border near to the southern end of the eastern wing of the Sierra Madre Occidental, both species belong to the group characterised by flowers of funnel-shaped corolla with longer tube than the corolla lobes, short filaments and included anthers in the throat, features different from those of the type species D. erythrorhiza and related species with rotated flowers with short tube and long corolla lobes, long exerted filaments and anthers. Based on the mentioned floral-morphological differences — similar to those detected formerly in the genus Edithea Standl. — a new section is established for a group of five species under the name Paradeppea .

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Community Ecology
Authors: A. García-Villaraco Velasco, A. Probanza, F. Gutierrez Mañero, B. Ramos, and J. Lucas García

Activity and functional diversity of rhizosphere bacterial communities and fungal composition were studied in order to assess the effects of different genotypes (N8035, N224 and N8637) of Arabidopsis thaliana on these communities growing in different soils. Genotype effect and soil effect were studied independently. Also, the interactions between both factors (genotypes and soils) were considered. The activity was determined by thymidine and leucine incorporation analysis, and Biolog ECO plates were used to study bacterial functional diversity. Additionally, fungi groups (genera and/or species) were studied in the different rhizospheres. Statistical differences on thymidine incorporation between plant genotypes were only found in two of the soils. In addition, functional diversity (measured by Shanonn-Weaver index), showed statistical differences only in soil 1 for line N8035 (line B) vs . the other lines. Redundancy analysis (RDA) performed with Biolog data indicated and important effect of soil type, but also an effect of genotype since line N8035 (line B) was separated from the other lines within each soil in the RDA ordination, in spite of genotypic differences between them were minimum. Furthermore, carboxylic acids and amino acids were found to be the Biolog plate substrates with more influence in samples ordination in the Redundancy Analysis (RDA). However, fungi seem to be less labile to plant selection than bacteria probably due to a lower turn-over time of fungi than bacteria coupled with the short phenology of Arabidopsis . In this paper, plant-soil-micro-organism relationships in the rhizosphere were studied, and the complex interactions between them were highlighted. More studies are necessary to go deep in these interactions and to be able to asses the impact of genetically modified plants.

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The best alternative for reducing citrus production costs is mechanization. Machine vision is a reliable technology for the automatic inspection of fresh fruits and vegetables that can be adapted to harvesting machines. In these, fruits can be inspected before sending them to the packinghouse and machine vision provides important information for subsequent processing and avoids spending further resources in non-marketable fruit. The present work describes a computer vision system installed on a harvesting machine developed jointly by IVIA and a Spanish enterprise. In this machine, hand pickers directly drop the fruit as they collect it, which results in an important increase of productivity. The machine vision system is placed over rollers in order to inspect the produce, and separate those that can be directly sent to the fresh market from those that do not meet minimal quality requirements but can be used by the processing industry, based on color, size and the presence of surface damages. The system was tested under field conditions.

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The new Guettarda species of Oaxaca (Mexico) is related to G. foliacea Standl. of a distribution from Tabasco and Chiapas to Panama, but differs by having long acuminate and falcate leaves with lineolate quaternary nerves on the abaxial surface, inflorescences with very short ovate and glabrous bracteoles and much shorter flowers with 8–9 mm long corolla tube.

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