Tesis Agronomía

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    Evaluación de una especie de fitoseido (Acari: phytoseiidae) para el control de Tetranychus urticae (Acari: tetranychidae) en rosa spp
    (2022-09) Pico Martínez, Christian Alexander; Santana Mayorga, Rita Cumandá
    The two-spotted mite, Tetranychus urticae Koch, is one of the most important phytophagous mites in agriculture due it is able to feed on a large number of plant species, its wide geographical distribution and the number of cases of resistance to different acaricidal products. In view of its importance, numerous studies have been carried out to evaluate alternative methods of control, such as biological control. In this research, the effect of the prey density (Tetranychus urticae) on the consumption and reproduction rates of Typhlodromalus sp. was evaluated in laboratory conditions. Regarding the predation rate, an increase in consumption was observed as the prey density increased, reaching a maximum of 11.2 eggs and 5.2 individuals/predator, respectively. Similarly, a positive effect of increasing prey density on the reproductive rate Typhlodromus sp. female, measured as the number of eggs laid per female per day, was observed. According to the results, it is possible to conclude that Typhlodromus sp. shows biological attributes that would allow it to increase its population levels accordingly increases in the pest population, which is a desirable characteristic of natural enemies to be included in integrated pest management programs.
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    Respuesta funcional de una especie de fitoseido (Acari: phytoseiidae) sobre diferentes densidades de Tetranychus urticae (Acari: tetranychidae) como base para un programa de control biológico
    (2022-09) Machado Freire, Ericka Belén; Santana Mayorga, Rita Cumandá
    Tetranychus urticae Koch is considered one of the most widely distributed phytophagous mites worldwide and is also the most polyphagous species of Tetranychidae, with the largest number of cases of resistance to a wide number of pesticide molecules have been recorded. Given its importance, several studies have been carried out to evaluate the efficiency of more environmentally friendly control methods, such as biological control. In the present study, the functional response of a phytoseiid species on different densities of Tetranychus urticae was evaluated as a basis for a biological control program. The functional response of Typhlodromalus sp. on different T. urticae egg densities (5, 10, 20, 30 and 40 eggs/predator female) and mobile phases, larvae and nymphs (2, 4, 8 and 16 mobile phases/predator female) was studied in separate bioassays under laboratory conditions. The consumption rate of eggs and mobile phases followed a functional response of quadratic type, which was evidenced by a regression coefficient of 97.27% for eggs and 98.8% for mobile phases. Consumption rate ranged from 2.8 eggs/female at the density of 5 eggs offered and increased to 11.2 eggs/female at the highest density of eggs offered (40 eggs/arena). Likewise, the consumption rate of mobile phases increased from 1.6 to 5.2 individuals/female of the predator. Finally, values of Th= 0.0492 h and a= 1.7064 h-1 were obtained for the eggs and Th= 0.2125 h and a= 0.8262 h-1 for the mobile phases (larvae and protonymphs). Based on the results, the predator, Typhlodromalus sp. showed a high consumption capacity with low handling times and high attack rates, which suggests that this species could be included in integrated management programs, which include biological control of T. urticae in rose plantations.