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Commercial pesticides were selected, mixed and applied in coconut stems (Cocos nucifera Linn.) by endotherapy with various adjuvants. Tissue samples from the coconut stem were collected at different heights and days, and subjected to extraction and analysis by modified QuEChERS (“Quick, Easy, Cheap, Effective, Rugged and Safe") and UHPLC-MS/MS (ultra-high-performance liquid chromatography–tandem mass spectrometry). The translocations of 3-hydroxy-carbofuran, carbendazim, carbofuran, difenoconazole, imidacloprid, thiabendazole, thiamethoxam, thiophanate-methyl and spirodiclofen, using salts, citric acid and organosilicones as adjuvants, were evaluated and compared 2 and 30 days after the applications. The results showed that each pesticide had a different translocation profile, modified by the presence of the adjuvants. The most significant modifications were obtained using organosilicones, which enhanced the translocation process by 40% for most pesticides, followed by acidification (30%) and the addition of salts (22%).

The coconut mite, Aceria guerreronis Keifer, is one of the main pests of the coconut tree (Cocos nucifera L.) worldwide. Its control is mainly based on the use of acaricides. However, due to the habitat of this pest mite, which is protected by fruit bracts that act as a physical barrier, chemical control is often inefficient. Thus, natural enemies have been studied as an alternative to acaricides. We evaluated the functional and numerical responses of Amblyseius aerialis (Muma) to increasing densities of A. guerreronis (40, 80, 160, 240 and 360) and additionally the oviposition rates of the phytoseiid A. aerialis over 11 days on different food sources: coconut pollen, A. guerreronis and a mix of pollen and A. guerreronis. Our results showed that Amblyseius aerialis showed a type III functional response, where prey consumption increasing as the density of A. guerreronis increased, with a maximum consumption of up to 175 prey per predator. All the prey densities allowed female oviposition. The number of eggs laid by A. aerialis increased with increasing prey density and stabilized between 240 and 360 A. guerreronis individuals, with an average oviposition of 1.7 eggs/female. Furthermore, our results showed that all the food sources (coconut pollen, A. guerreronis and a mix of pollen and A. guerreronis) supported oviposition. The mean oviposition was approximately 1.5 eggs/female on all the food sources. Our study suggests that A. aerialis can be effective in the biological control of A. guerreronis. However, further studies are needed to investigate whether A. aerialis can explore the habitat of A. guerreronis and if that prey can support the development of immature stages and the reproduction of A. aerialis.

Resumo -O objetivo deste trabalho foi estimar os coeficientes de repetibilidade para produção de fruto e de albúmem sólido em coqueiro (Cocos nucifera) pelos métodos estatísticos da análise de variância (ANOVA), componentes principais (covariância e correlação) e análi-se estrutural (covariância). Detectou-se variabilidade significativa entre os híbridos em relação à produção de frutos e de albúmen sólido. Os coeficientes de repetibilidade foram menores quando foram usados os procedimentos da análise de variância e análise estrutural (correlação). Ao considerar satisfatório o nível de 90%, como critério de predição na escolha de híbridos com superioridade quanto às duas características, e tomando-se por base a estimativa do coeficiente de repetibilidade obtida pelo método dos componentes principais (covariância), recomenda-se realizar cinco e três avaliações para produções de frutos e de albúmen sólido, respectivamente.Termos para indexação: Cocos nucifera, seleção, método de melhoramento, genética quantitativa. Estimation of repeatability coeficients for production of fruits and solid albumen in hybrids of coconut palmAbstract -The objective of this work was to estimate the coefficient of repeatability for production of fruits and solid albumen in coconut palm (Cocos nucifera) using statistical methods of the variance analysis (ANOVA), main components (covariance and correlation) and structural analysis (covariance). Significant variability was detected between hybrids for fruits and solid albumen productions. Repeatability coeficients obtained by the variance analysis and structural analysis (correlation) showed the smallest values. If the level of 90% is considered sufficient to select hybrids with relative superiority for fruit and solid albumen productions based on the estimation of repeatability by the main components method (covariance), then it would be recommended to perform five and three evaluations for fruit and solid albumen productions, respectively.