Centro Agrícola

5-15

Authors: Sofía Peñaherrera Villafuerte, Galo Cedeño García, Fernando Solórzano Alcívar, George Cedeño-García, Pedro Terrero Yépez

The main objective of the research was to evaluate the efficacy of mixtures of Trichoderma spp. and palm oil in the management of cocoa moniliasis. The experiment was carried out during 2016 in a 40-year-old polyclonal plantation, made up of clones EET-19, EET-95 and EET-103, sensitive to moniliasis. The treatments evaluated were: palm oil + Trichoderma koningiopsis and T. stromaticum (T1), palm oil + T. ovalisporum (T2), T. koningiopsis + T. stromaticum (T3), T. ovalisporum (T4), Hydroxide of Copper (T5) and a control treatment (T6). The main variables recorded were: the area under the disease progress curve (ABCPE), the control efficacy, the yield and the net economic benefit. The data were subjected to the analysis of variance and the comparison of means through the Tukey test, with a 5 % probability of error. The treatments significantly influenced the evaluated variables. T1 and T2 showed the highest moniliasis control efficacy with 50.27 and 41.68 % respectively, in addition to having lower disease intensities over time (ABCPE) compared to control. Likewise, these treatments showed a greater increase in the yield of dry grains with 30.18 and 29.46 %, in their respective order; at the same time, they achieved the highest net economic benefits with 1094 and 1050 USD ha-1. The mixtures of Trichoderma spp. and palm oil were effective in managing the disease and increase the yield and economic benefit of cocoa.

22-30

Authors: Osmany de la Caridad Aday Díaz, Héctor García Pérez

The orange rust of the sugar cane (Puccinia kuehnii (W. Krüger) E. J. Butler) is a disease of potential danger for the sugar industry in Cuba. The objective of the research was to determine the spatial distribution of orange rust in leaves infected by P. kuehnii, type of distribution of the pustules and the possible use of a quantitative variable that allows estimating the affected leaf area with a superior precision to observation of the human eye. From the cultivar C01-227 (susceptible to the disease), 25 leaves were collected and the +5 leaf was selected. The type of spatial distribution of the pustules was determined by calculating the variance / mean ratio and the Morisita index. A maximum of 6.88 pustules per cm2 was determined in leaves with 25 % of affected leaf area and an average of 2.26 in leaves with affectation from 5 to 25 %. The pustules for square centimeters was significantly higher in the middle and apical thirds; but in the third of the leaf, their value average or their maximum is not related directly with area affected in the leaf.

41-53

Authors: Alonso David Ojeda-Falcón, Olgioly Domínguez-Quintero

An agroecological Voisin’s Rational Grazing production system was established in 2013 in Barinas, Venezuela, with the aim of studying a sustainable agroecological route in acid-sandy soils. A pasture of 27 ha with Urochloa brizantha and Urochloa ruziziensis was divided in 64 paddocks. Four treatments were established: application of a single dose of 1.5 Mg ha-1 asphaltic emulsion; single dose of 440 kg ha-1 of phosphoric rock; asphaltic emulsion with phosphoric rock, with the same previous dose, and control, only with Voisin’s Rational Grazing. Four replicates of each treatment were established in 16 randomly chosen paddocks in which periodic soil and vegetation samplings were carried out. The highest yields of dried matter in t ha-1 yr-1 of pasture corresponded to asphaltic emulsion (34-62) and asphaltic emulsion with phosphoric rock (54-48) in comparison to the control (22-31) and phosphoric rock (24-25) treatments, for years 2015 and 2016, respectively. This brought about better quality pastures, from the first year of the management the pasture yields tripled and an increase of the animal load from 1.2 to 3.7 LU ha-1 between 2015 and 2016, and to 4.3 LU ha-1 in 2017 was achieved. Applying a single dose of asphaltic emulsion aided to accelerate the regular increases with time. The labile fractions of P showed that Voisin’s Rational Grazing induced a high phosphoric fertility which displaced phosphorous as the main limiting factor in primary productivity of these soils of low natural fertility, that are widely distributed in savannah ecosystems and the Neotropic.

66-74

Authors: Isbel Rodríguez Seijo, Pedro Martínez Campos, Ubaldo Álvarez Hernández, Arahis Cruz Limonte, Elier Mora Pérez

The objective of this work was to evaluate the effect of planting distances of 1.60 m and furrow with a wide base (0.40 m x 1.40 m) on the growth and agricultural yield of sugarcane. The experimental design used was random blocks with four replications and two treatments equivalent to the plantation frameworks most used in this crop in Cuba; the cultivar used was C90-469. At 30 days after planting (ddp) the number of shoots per linear meter was evaluated; at field closure, 120 ddp, the length, width and number of active leaves and the leaf area per plant were evaluated; at 360 ddp, length, diameter and number of internodes, length of stems, number of stems per linear meter, weight of stems, number of stems per hectare, and agricultural yield were evaluated. In the framework of a wide-base furrow plantation, there was an increase in the number of shoots per linear meter; the leaf area, mean internodes, length and diameter of the same, length of the stems and weight of the stems was less than the planting distance of 1.60 m; however, the number of stems per hectare at the time of harvest was higher, reaching 97 290 and an increase in agricultural yield of 11.8 % in relation to the distance 1.60 m.

84-88

Authors: Rosabel Rodríguez Rojas, Vladimir Nuñez Caraballo, Sinaí Barcia Sardiñas, Roberto Valdés Herrera

Obtained a methodology it permits carry out a diagnosis and effective characterization of the agricultural urban production of the blessed cities white of egg and Cienfuegos, by keeping in mind by having the location of the organoponics, cercaniases to fixed sources of emission of polluting agents and ways of access, cultivations that it develops, areas that occupy, as well as the environment built. For it carried out the update and mapping of active organoponics in the cities object of study.