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Ramirez F.,Pontifical Xavierian University | Davenport T.L.,University of Florida | Fischer G.,National University of Colombia | Pinzon J.C.A.,National University of Education of Colombia

The quantitative floral inductive role of the age of the last vegetative flush was investigated in replicated trials of two cultivars of mango (Mangifera indica L.), Keitt and Tommy Atkins, growing in tropical conditions of Cundinamarca State in Colombia. Empirical observations have indicated that stems must be in rest for sufficient time, generally 4 to 5 months, to be induced to flower in the absence of cool temperatures.Twelve trees per cultivar were tip-pruned to stimulate a synchronous flush of vegetative growth at the beginning of the experiments. The first of four sets, each consisting of three replicate trees among the 12, were sprayed with 4% potassium nitrate on a 2-week schedule beginning 2 months after the pruning date. Biweekly sprays continued in this first set until a growth response was observed, whereupon the set was retired from further observations, and the second set of three synchronized trees began receiving biweekly spray treatments until they initiated a growth flush. The schedule continued through the four successive sets of trees until the age of stems necessary to induce a flowering response was determined. Treatment applications were quantified using a one-m-square quadrate to determine the numbers of resting stems and vegetative and /or reproductive shoots contained within. KNO3 sprays applied 3 months after the pruning date stimulated initiation of vegetatively induced shoots in both 'Keitt' and 'Tommy Atkins' trees. Synchronous generative shoot initiation in 'Keitt' trees occurred in ≈75% and 100% of the stems after KNO3 sprays applied 5 and 6 months after the pruning date, respectively. Tommy Atkins, a cultivar that is more difficult to induce to flower than 'Keitt', had 18% of shoots flowering after the 5-month application and 100% flowering after the KNO3 application 6 months after the pruning date. None of the nontreated orchard trees flowered during this time. Stem age was the key factor correlated with flowering. The experimental trees, which were naturally habituated to experience two flowering periods per year, each within separate sections of tree canopy, were stimulated to produce one annual synchronized flowering event throughout the tree canopy as a result of the treatments. Source

This study explores the perception of citizens of the city of Bogota (Colombia) on the current state of the environment at local, national and global level, and the prospect of what it will be in the future, in order to provide guidance for the development of environmental components of citizenship education. It also investigates the allocation of responsibility for environmental management in the future. Participants were 118 people, men and women aged over 18 years with different levels of schooling. The instruments used were the Environmental Future Scale by Gifford et al. (2009) to which two items relevant to the assessment of the environment in Colombia were incorporated, and the Allocation Scale for Environmental Responsibility by Barros, Pinheiro and Gunther (2010). Results showed moderate pessimism for the national level, and high for the international and local case. Regarding the allocation of responsibility, an external locus of control was identified in terms of the causes of environmental degradation, where the main actors mentioned were other people and the national government. Findings are discussed in terms of a comparison with similar studies elsewhere in the world and of its implications for promoting pro-environmental behavior and the attribution of responsibility on the part of the citizens of Bogota, as well as the effect of the media assessing the state of the environment. Source

Ramirez F.,University College of Cundinamarca | Fischer G.,National University of Colombia | Davenport T.L.,Research and Development | Pinzon J.C.A.,National University of Education of Colombia | Ulrichs C.,Humboldt University of Berlin
Scientia Horticulturae

The cape gooseberry (Physalis peruviana L.) is a shrub found native in the Andes that bears tomato-like fruit, which are sold commercially and exported from Colombia. We describe the BBCH-based phenological scale for this crop that was developed by observing three cape gooseberry ecotype accessions during a two-year study. The proposed BBCH phenological scale uses seven principal growth stages out of the nine principal stages identified for solanaceous fruits. The principal growth stages are (0) germination, (1) leaf development, (2) formation of side shoots, (5) inflorescence emergence, (6) flowering, (7) development of fruit and (8) ripening of fruit and seed. Early growth stages (0-1) in cape gooseberry are similar to the developmental stages of other solanaceous plants. The first bifurcation (stage 2) marks the beginning of floral development (stage 5). Thereafter, simultaneous developmental stages occur throughout the plant's phenology. It is common to observe early flowers, fully open flowers, immature and mature fruits on the same plant. The BBCH phenological scale developed for cape gooseberry is a useful tool for management and research practices and for subsequent investigations on any of the developmental stages the plant passes through. © 2013 Elsevier B.V. Source

Ramirez F.,University College of Cundinamarca | Davenport T.L.,Vivafresh Technologies | Fischer G.,National University of Colombia | Pinzon J.C.A.,National University of Education of Colombia | Ulrichs C.,Humboldt University of Berlin
Scientia Horticulturae

We propose a convenient, easily observable set of landmark developmental stages during vegetative and flowering flushes and fruiting events to characterize the changes through which individual growing mango shoots pass in the tropics and subtropics. Individual non-growing stems are in the Resting stage (R), when the apical bud (following a previous vegetative growth event) or lateral buds (following a previous flowering event) are dormant. A flush event is one in which the resting buds on many stems in a section of tree canopy initiate growth (asynchronous flush) or when the entire canopy initiates bud growth at once (synchronous flush). The stages describing vegetative shoot growth are: Vegetative Bud Emergence and Development stage, Elongating Green Leaf stage, Limp Red Leaf stage (LRL), Immature Green Leaf stage, and Mature Green Leaf stage. Reproductive growth stages in purely flowering, or generative, shoots are: Floral Bud Initiation, Emergence and Development stage, Early Panicle Elongation stage, Mid-size Panicle Early Anthesis stage, and Full-size Panicle Maximum Anthesis stage. Fruiting stages are: Emergent Fruit stage, Small-size Green Fruit stage, Mid-size Green Fruit stage, Near Full-size Immature Fruit stage, and the Full-size Mature Fruit stage. Mixed shoots, bearing both leaves and lateral inflorescences at each node, exhibit characteristics of both vegetative and flowering shoots. Landmark stages for Tommy Atkins and Keitt, two cultivars commercially growing in the Americas, were observed in tropical orchards near the village of La Mesa, Colombia. Tommy Atkins leaves had a more intense red coloration during the LRL than did 'Keitt'. More pedicels were found in 'Tommy Atkins' than in 'Keitt' during panicle development. Young fruits of 'Tommy Atkins' developed their distinctive, dark red coloration, whereas 'Keitt' fruit developed less intense reddish coloration once they were mature. Aside from these minor phenotypic differences in distinctive shoot and stem developmental stages, attempts to ascribe a distinct phenological pattern of mango tree growth and development are impractical. Each stem terminal or groups of stem terminals borne on scaffolding branches act as independent structures influenced by environmental conditions, such as temperature, water relations, and nutrition coupled with their physiological age resulting in widely variable tree responses even in similar environments. © 2014 Elsevier B.V. Source

Cano J.R.,National University of Education of Colombia
Proceedings - Frontiers in Education Conference, FIE

This document is part of a research done from Master Science in Telecommunications Engineering program of the Universidad Nacional de Colombia, that links three strategies for interconnection1 which aim is to rescue the culture in the country from the schools. The current document shows a development model to be incorporated in Colombian education and describes three fundamental axes for its implementation. Initially a description of the present educative organization in Colombia for the levels of elementary and high school education is done. Then, it focuses attention on the obligatory area of Technology and Computing extending the information with the advantages that this area has to the model by its varied alternatives of implementation and the promotion of competences for this decade. The proposal is articulated with the use of free software, the advantages that this has against the alternative of proprietary software and the existing relation with the increase in the use of pirate software in Latin America. The third axis considers the context of the competences that the teachers who implement the model must have, and finally, there is a description of the integration of the three elements mentioned and allows being viable within the educative policies in the following decade for Colombia. © 2010 IEEE. Source

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