Influence of the training system on the agronomic behavior and grape composition of Albariño in Rías Baixas apellation

The aim of this study was to evaluate if early defoliation can be an alternative to bunch thinning in limiting yield and improving quality in grapes of the white cultivar Loureiro (Vitis vinifera L.), grafted onto 1103P. The field trial had been set up in a commercial vineyard in Vinhos Verdes Region (Northwest of Portugal, 41º 48? 53? N, 8º 24? 42? W). Treatments studied, performed five days before full bloom were: LR5 ? Leaf removal of the first five basal leaves, performed manually, LR8 ? Leave removal of the first eight basal leaves, LRM ? mechanical leaf removal and C ? the control, without defoliation. This paper reports the results of four years (2010-2013). The results presented a significant removal of main leaf area after defoliation principally in the most intensive treatment (LR8) but at harvest, the total leaf area had been compensated by lateral regrowth and no statistical differences between the treatments and the control were found. Early defoliation caused a decrease in fruit set and also a significant reduction in the diameter of the berry within the more severe defoliation treatments (LR5 and LR8). Yield factors were also significantly affected by the defoliation, causing a reduction of bunch weight and in 2013 a yield reduction in LR8 and LRM, and in 2010 in LR8. Conversely, LR5 presented a yield always similar to the control C. The reduction of cluster compactness and the substantial improvement of the microclimate at the cluster level significantly reduced bunch rot incidence in the defoliated modalities compared to control. No carry-over effects, along the four years trial were observed Early defoliation proved to be a canopy management technique that can have a strong impact in the final quality of grapes, reducing the compactness and lower the incidence and intensity of bunch rot, even if the reduction of yield observed in other papers had not been observed in all modalities.

Characterization of vineyard's canopy through fuzzy clustering and svm over color images

In this work we propose an image acquisition and processing methodology (framework) developed for performance in-field grapes and leaves detection and quantification, based on a six step methodology: 1) image segmentation through Fuzzy C-Means with Gustafson Kessel (FCM-GK) clustering; 2) obtaining of FCM-GK outputs (centroids) for acting as seeding for K-Means clustering; 3) Identification of the clusters generated by K-Means using a Support Vector Machine (SVM) classifier. 4) Performance of morphological operations over the grapes and leaves clusters in order to fill holes and to eliminate small pixels clusters; 5)Creation of a mosaic image by Scale-Invariant Feature Transform (SIFT) in order to avoid overlapping between images; 6) Calculation of the areas of leaves and grapes and finding of the centroids in the grape bunches. Image data are collected using a colour camera fixed to a mobile platform. This platform was developed to give a stabilized surface to guarantee that the images were acquired parallel to de vineyard rows. In this way, the platform avoids the distortion of the images that lead to poor estimation of the areas. Our preliminary results are promissory, although they still have shown that it is necessary to implement a camera stabilization system to avoid undesired camera movements, and also a parallel processing procedure in order to speed up the mosaicking process.

An Analysis of the Influence of Students´ Technological Culture on Their Technology

decade has raised the interest among the research community on the acceptance and use of these systems by both teachers and students. At first, the implementation of LMS was based on their technical design and the adaptation of the learning processes to the virtual environment, neglecting students’ characteristics when the systems were deployed, which led to expensive and failing implementations. The Unified Theory of Acceptance and Use of Technology (UTAUT) proposes a framework which allows the study of the acceptance and use of technology that takes into consideration the students’ characteristics and how they affect the acceptance and the degree of use of educational technology. This study questions the role of the user’s attitude towards use of LMS and uses the UTAUT to examine the moderating effect of technological culture in the adoption of LMS in Spain. The results from the comparison and analysis of three different models confirm the relevance of attitude towards use as an antecedent of intention to use the system, as well as the important moderating effect of gender and technological culture. The discussion of results suggests the need for a more in-depth analysis and interrelations of cultural dimensions in the adoption of educational technologies and learning management systems

Improved walnut mass micropropagation through the combined use of phloroglucinol and FeEDDHA

Despite the socioeconomic importance of walnut trees, poor rooting and recalcitrance to in vitro culture have hampered the establishment of high-yield clonal plantations. To improve walnut micropropagation, we introduced several modifications to current methods and evaluated the effects on microshoot performance and acclimatization. Nine selected genotypes (13-year-old trees) of the commercial hybrid Juglans major 209 x J. regia were cultured in vitro on DKW-C medium supplemented with 4.4 µM BA and 50 µM IBA. A protocol was developed that relies on the use of 0.40 mM phloroglucinol during shoot multiplication, 0.20 mM previous root induction, and 6.81 mg/L Fe3+ (FeEDDHA). Moreover, the addition of 83.2 µM glucose during the root expression phase significantly improved plant survival during acclimatization. Phloroglucinol promoted microshoot elongation but inhibited rooting, especially at concentrations above 0.40 mM. Replacing FeEDTA by FeEDDHA diminished chlorotic symptoms and improved rooting, with up to 90% microshoots developing viable roots. Likewise, glucose was more efficient than sucrose or fructose in promoting plant survival. At the proposed working concentrations, neither glucose nor FeEDDHA caused any noticeable deleterious effect on walnut micropropagation. Microscopic analysis revealed the physical continuity between adventitious roots and stem pericycles. Analysis of leaf genomic DNA with eight polymorphic microsatellite markers was supportive of the clonal fidelity and genetic stability of the micropropagated material. Successful clonal plantations (over 5,800 ramets) have been established by applying this protocol.