The use of adequate plant densities can be a key and important factor to increasing rice productivity (Oryza sativa L.). Therefore, the objective of this study was to investigate the influence of four population densities (DP) on the growth and agricultural production of rice. The INCA-LP-5 cultivar was managed between April and August 2016. The treatments were distributed in a randomized block design, with four population densities (250,000, 350,000, 450,000 and 550,000 plants ha-1) and five replications. The effects of the PD were verified by observing the following parameters: evaluated the following indicators, plant height (cm), tiller number per hill, number of panicles per m2, number of grains per panicle, panicle length (cm), 1000 grains weight (g) and grain yield (t ha-1). The results indicated that the DP of 450,000 plant ha-1 showed the best results in rice productivity. These results were possible because the DP of 450,000 plants ha-1 increased the morphological and productive parameters in relation to the other densities studied. The findings of this study indicated that the use of optimal plant densities plays a fundamental role in the growth and productivity of rice, which leads to a sustainable development of the crop.
This work was carried out in the urban farm "Las Mercedes" in the municipality of Matanzas, Cuba, with the objective of evaluating the current use and management of soil resources to avoid its degradation and increase sustainable food production. The main agro-productive limitations of edaphic character were determined, and the fields were georeferenced. A field diagnosis was carried out to evaluate the effective depth, maximum slope, stoniness and presence of carbonates in order to establish the agrological class of the crop fields. The inadequacies in the use of the soils according to their suitability were established and the conservationist use and management of the fields was recommended in order to control soil degradation and achieve sustainable agricultural development. It was proposed to improve the current use and management of seven fields with agrological class IV, to work and arrange the furrows in contour in three fields with a 5-7 % slope, to change the use of two fields with agrological class VI and to subdivide two fields with different agrological classes. In addition, it was proposed to develop a rehabilitation project to improve the current use of a field with susceptibility to flooding and surface and internal drainage problems, whose diagnosis was limited in magnitude and quality in the present study.
Cuban forests are an important source of non-timber forest products, with a historical tradition of consumption, mainly among peasants. However, there is currently a trend towards the loss of the traditional use of plants. With the objective of disseminating knowledge about the potential use of these forest products, little diffused among current generations, a characterization of some groups of ethnobotanical interest present in the living collections of plants of the Villa Clara Botanical Garden is presented, as a tool for environmental education. The ethnobotanical information was obtained from the bibliographic review, mainly from published works on case studies in Cuba. The groups of utilities defined in the study were: food, handicraft, source of fats and oils, exudates and extracts. The forest products as a source of resources for handicrafts with ten examples, followed by those that constitute a source of food (8), extracts (7), exudates (4), and fats and oils (2), are the ones that resulted among the little diffused at present. These constitute a highly valuable collection in the Botanical Garden to maintain the patrimonial legacy for current and future generations. The application of these results is materialized through the talks incorporated into the tours with visitors.
With the objective of determining the response of the production and quality of maize forage inoculated with arbuscular mycorrhizal fungi and their association with canavalia, an experiment was carried out at Centro Universitario Municipal of Cumanayagua, in a randomized block design with five treatments and four replications: maize + Funneliformis mosseae, maize + F. mosseae + Canavalia ensiformis, maize + C. ensiformis, maize + NPK and maize on grayish brown soil. Polyethylene bags with a capacity of 2 kg of soil were used. At planting, the maize was inoculated with F. mosseae by the seed coating method. Fifteen days after emergence, the canavalia was planted. At 60 days, stem diameter was measured and at 75 days, biomass production and crude protein percentage of maize, canavalia and their association were determined. The highest growth and production of maize was found in the presence of mineral fertilization. Biomass production and gross protein of forage responded positively to mycorrhizal inoculation of maize and the association with canavalia, with the greatest benefits in the application of both practices. In the association forage, biomass and gross protein production increased by 24.6 and 15.03 %, and 29.8 and 23.4 %, respectively, relative to maize forage alone. It was higher when maize was inoculated with mycorrhiza. The inferior performance of coapplication with respect to mineral fertilization suggests the need to supplement it with low doses of fertilizers to optimize its benefits.
