Tomato Cultivar Trial

The 2011 tomato trial evaluated 16 fresh market cultivars for yield potential and fruit quality.

Soil-Borne Pathogens Associated to New Crops of Cherry Tomato in the Province of Granada Spain

Soil-Borne Pathogens Associated to New Crops of Cherry Tomato in the Province of Granada Spain

Inoculum sources and Preservation in Soils of Phytophthora parasitica from Cherry Tomato in Continental Crop Areas in Southeast Spain

Inoculum sources and Preservation in Soils of Phytophthora parasitica from Cherry Tomato in Continental Crop Areas in Southeast Spain

Techniques for Area Discretization and Coverage in Aerial Photography for Precision Agriculture employing mini quad-rotors

Remote sensed imagery acquired with mini aerial vehicles, in conjunction with GIS technology enable a meticulous analysis from surveyed agricultural sites. This paper sums up the ongoing work in area discretization and coverage with mini quad-­?rotors applied to Precision Agriculture practices under the project RHEA.

Aerial Remote Sensing in Agriculture: A Practical Approach to Area Coverage and Path Planning for Fleets of Mini Aerial Robots

In this paper, a system that allows applying precision agriculture techniques is described. The application is based on the deployment of a team of unmanned aerial vehicles that are able to take georeferenced pictures in order to create a full map by applying mosaicking procedures for postprocessing. The main contribution of this work is practical experimentation with an integrated tool. Contributions in different fields are also reported. Among them is a new one-phase automatic task partitioning manager, which is based on negotiation among the aerial vehicles, considering their state and capabilities. Once the individual tasks are assigned, an optimal path planning algorithm is in charge of determining the best path for each vehicle to follow. Also, a robust flight control based on the use of a control law that improves the maneuverability of the quadrotors has been designed. A set of field tests was performed in order to analyze all the capabilities of the system, from task negotiations to final performance. These experiments also allowed testing control robustness under different weather conditions.

The use of wind pumps for greenhouse microirrigation: a case study for tomato in Cuba.

Crop irrigation is a major consumer of energy. Only a few countries are self-sufficient in conventional non-renewable energy sources. Fortunately, there are renewable ones, such as wind, which has experienced recent developments in the area of power generation. Wind pumps can play a vital role in irrigation projects in remote farms. A methodology based on daily estimation balance between water needs and water availability was used to evaluate the feasibility of the most economic windmill irrigation system. For this purpose, several factors were included: three-hourly wind velocity (W3 h, m/s), flow supplied by the wind pump as a function of the elevation height (H, m) and daily greenhouse evapotranspiration as a function of crop planting date. Monthly volumes of water required for irrigation (Dr, m3/ha) and in the water tank (Vd, m3), as well as the monthly irrigable area (Ar, ha), were estimated by cumulative deficit water budgeting taking in account these factors. An example is given illustrating the use of this methodology on tomato crop (Lycopersicon esculentum Mill.) under greenhouse at Ciego de Ávila, Cuba. In this case two different W3 h series (average and low wind year), three different H values and five tomato crop planting dates were considered. The results show that the optimum period of wind-pump driven irrigation is with crop plating in November, recommending a 5 m3 volume tank for cultivated areas around 0.2 ha when using wind pumps operating at 15 m of height elevation.

A computer program for the analysis of the dynamic bending-torsion coupling in bridges using a mini-computer

The analysis of modes and natural frequencies is of primary interest in the computation of the response of bridges. In this article the transfer matrix method is applied to this problem to provide a computer code to calculate the natural frequencies and modes of bridge-like structures. The Fortran computer code is suitable for running on small computers and results are presented for a railway bridge.

Genetic diversity and relationships in accessions from different cultivar groups and origins in the tree tomato (Solanum betaceum Cav.)

Abstract Tree tomato (Solanum betaceum) is an Andean small tree cultivated for its juicy fruits. Little information is available on the characterization of genetic resources and breeding of this neglected crop. We have studied the molecular diversity with AFLP markers using 11 combinations of primers of a collection of 25 S. betaceum accessions belonging to four cultivar groups, most of which had been previously morphologically characterized, as well as one accession of the wild relative S. cajanumense.Atotal of 197 AFLP fragments were scored, of which 84 (43 %) were polymorphic. When excluding S. cajanumense from the analysis, the number of polymorphic AFLP fragments was 78 (40 %). Unique AFLP fingerprints were obtained for every accession, but no AFLP fragments specific and universal to any of the four cultivar groups were found. The total genetic diversity (HT) of cultivated accessions was HT = 0.2904, while for cultivar groups it ranged from HT = 0.1846 in the orange group to HT = 0.2498 in the orange pointed group. Genetic differentiation among cultivar groups (GST) was low (GST = 0.2248), which was matched by low values of genetic distance among cultivar groups. The diversity of collections from Ecuador, which we hypothesize is a center of diversity for tree tomato, was similar to that from other origins (HT = 0.2884 and HT = 0.2645, respectively). Cluster and PCoA analyses clearly separated wild S. cajanumense from the cultivated species. However, materials of different cultivar groups and origins were intermingled in both analyses. The Mantel test correlation coefficient of the matrices of morphological and AFLP distances was low (-0.024) and non-significant. Overall, the results show that a wide diversity is present in each of the cultivar groups, indicate that Ecuador may be regarded as a center of accumulation of diversity for this crop, and confirm that AFLP and morphological characterization data are complementary. The results obtained are of value for the conservation of genetic resources and breeding of tree tomato, as an assessment of the genetic diversity and relationships among differen

Towards a ground navigation system based in visual feedback provided by a mini UAV

This paper addresses initial efforts to develop a navigation system for ground vehicles supported by visual feedback from a mini aerial vehicle. A visual-based algorithm computes the ground vehicle pose in the world frame, as well as possible obstacles within the ground vehicle pathway. Relying on that information, a navigation and obstacle avoidance system is used to re-plan the ground vehicle trajectory, ensuring an optimal detour. Finally, some experiments are presented employing a unmanned ground vehicle (UGV) and a low cost mini unmanned aerial vehicle (UAV).

The Tomato Processing Industry in Portugal

Portugal is a major producer of tomatoes for processing. Is export industry now ranks 4th worldwide; before the strongly protectionist European Common Market policy initiated in the early 1970s it ranked 3rd. The culture of tomatoes for processing in irrigated areas of Portugal is favored by the dry, warm summer that characterizes Mediterranean climates. In addition the summer in Portugal is not too hot for a good tomato set.

Simulation of AC, DC, and AC-DC coupled mini-grids. In search of the most efficient system

Renewable energy hybrid systems and mini-grids for electrification of rural areas are known to be reliable and more cost efficient than grid extension or only-diesel based systems. However, there is still some uncertainty in some areas, for example, which is the most efficient way of coupling hybrid systems: AC, DC or AC-DC? With the use of Matlab/Simulink a mini-grid that connects a school, a small hospital and an ecotourism hostel has been modelled. This same mini grid has been coupled in the different possible ways and the system’s efficiency has been studied. In addition, while keeping the consumption constant, the generation sources and the consumption profile have been modified and the effect on the efficiency under each configuration has also been analysed. Finally different weather profiles have been introduced and, again, the effect on the efficiency of each system has been observed.

Relations between resistance of fruit and skin characteristics in tomato varieties.

Varietal differences in physical properties of processing tomato fruits related with resistance are determined. Mean values of skin resistance and firmness are highly correlated with rupture of the fruits by quasi-static compression and by impact. Skin resistance is dependent on the features of the epidermis, studied microscopically.

Fruit firmness and skin resistance of processing tomato varieties tested in Badajoz (Spain), related to mechanical harvesting.

Determinations of resistance to damage were carried out in a total of 31 tomato varieties for processing, with the purpose of choosing the most suitable ones for mechanical harvesting. The characteristics studied include: puncture, deformation and rupture of the fruits, the ease of detachment of the fruits also being determined. Seventeen varieties were chosen, for further tests, with values 0.76 to 1.7 2 N of resistance to puncture; 3 to 9 N/mm of resistance to compression and 2.16 to 29.40 N resistance to detachment.