The cirus and papaya are the main perennial fruit trees produced in Brazil, especially in the state of Roraima. Among the most important pests affecting the culture of citrus in Roraima, Schizotetranychus hindustanicus is highlighted; among the most important pests affecting the culture of papaya Polyphagotarsonemus latus. Despite the great infestations and damages caused by these mites-pest, there is no bioecological information about these species supporting programs of integrated management of these mites in the state of Roraima. Studies to understand the population dynamics of pests in loco are very important to design strategies of integrated management of them, allowing the producer to take actions when the pests are less favored by environment conditions, increasing the chances of control. Thus, the objective of this work is to determine geographical distribution of Schizotetranychus hindustanicus, its population dynamics and the propensity of site of attack on the plant, in an orchard of orange and the population dynamics of Polyphagotarsonemus latus in an orchard of papaya, in Caracaraí, to prospect natural enemies for biological control and to suggest actions of management of these mites-pest in Roraima. For this, the thesis was divided in three chapters, the first one discusses the geographical distribution of S. hindustanicus and associated mites in Roraima, the second and the third chapters discuss the population dynamics of S. hindustanicus e de P. latus, respectively. A survey for detection of S. hindustanicus and potential natural enemies was accomplished in August and September 2015, in the fifteen cities of Roraima. Schizotetranychus Hindustanicus was found in all the fifteen of the state of Roraima. The predatory mites from the family Phytoseiideae: Amblyseiusaerialis (Muma), Iphiseiodeszuluagai Denmark & Muma e Euseiusconcordis (Chant) were the predators most abundant on the survey and they are the potential agents of biological control of S. hindustanicus. The population dynamics of S. hindustanicus was accomplished in an orchard of orange during the period from June 2016 to December 2018 in the municipality of Caracaraí, Roraima. The biggest densities of S. hindustanicus occured in the periods of smaller rainfalls. There was no difference among the density of egg in the different quadrants, strata and position of leaves on the branch, in the plant and the density in the whole plant. Thus, the sample of mites may be carried out in any position on the plant. Predatory mites Amblyseius (Phytoseiidae) were found during the research. The population dynamics of Polyphagotarsonemus latus was analyzed in a culture of papaya, in the city of Caracaraí-RR from the Februray 2016 to August 2017. Only 12 papaya plants were observed with symptoms of the attack of P. latus and of other pests. It is supposed to be related to the fact the experiment was located in a recently open area in the middle of a woodland which might have worked as a natural barrier against the pests. The main predator associated to P. latus is Amblyseius (Acari: Phytoseiidae). These results may be used as basis for the best management of Schizotetranychus hindustanicus and Polyphagotarsonemus latus in the cultures of orange and papaya in Roraima. Studies with the natural enemies observed are necessary to assess the efficiency on the biological control of these pests.
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