Cleiton A. Domingos

Diet-dependent life history, feeding preference and thermal requirements of the predatory mite Neoseiulus baraki (Acari: Phytoseiidae).

Neoseiulus baraki Athias-Henriot (Acari: Phytoseiidae) has been reported from the Americas, Africa and Asia, often in association with Aceria guerreronis Keifer (Acari: Eriophyidae), one of the most important pests of coconut (Cocos nucifera L.) in different parts of the world. That phytoseiid has been considered one of the most common predators associated with A. guerreronis in Brazil. The objective of this study was to evaluate the feeding preference and the effect of food items commonly present on coconut fruits and several temperature regimes on the life history of a Brazilian population of N. baraki. Completion of immature development was possible when N. baraki was fed A. guerreronis, Steneotarsonemus concavuscutum Lofego and Gondim Jr., and Tyrophagus putrescentiae (Schrank). Fecundity was highest on T. putrescentiae (39.4 eggs), followed by A. guerreronis (24.8 eggs). In choice tests, irrespective of the food on which N. baraki was reared, a larger number of adults of this predator chose leaf discs containing A. guerreronis than discs containing other food items, demonstrating a preference of the former for the latter as food. Egg to adult thermal developmental time was calculated as 84.2 degree-days, above a threshold of 15.8°C. This lower developmental threshold is higher than previously published for phytoseiid species from higher latitudes. Neoseiulusbaraki was shown to have higher biotic potential at 30°C (rm 0.29). The results suggest N. baraki to be a promising biological control agent of A. guerreronis, well adapted to survive and develop in areas with relatively high temperatures, where that pest prevails.

Comparison of two populations of the pantropical predator Amblyseius largoensis (Acari: Phytoseiidae) for biological control of Raoiella indica (Acari: Tenuipalpidae).

The red palm mite, Raoiella indica Hirst (Acari: Tenuipalpidae), was recently introduced in the Americas. It spread quickly throughout coconut palm growing areas, expanding considerably its host range. The invasion of this species has caused high economic impact in several countries. In Brazil, extensive areas are expected to be affected. For logistical reasons and other concerns, chemical control does not seem desirable for the control of this pest in most Latin American countries. Biological control of R. indica by introducing exotic natural enemies seems to be an important control measure to be considered. Surveys in many countries have shown that Amblyseius largoensis (Muma) (Acari: Phytoseiidae) is a very common predator on coconut palms. This study compared the biology of a population of A. largoensis found for a long time in association with R. indica in La Reunion Island (Indian Ocean) with a population from Roraima State (northern Brazil), where R. indica was first found about two and a half years ago. No significant differences were observed between populations in relation to the duration of different immature stages or total survivorship. However, the oviposition period, prey consumption and net reproductive rate were significantly higher for the La Reunion population, warranting further investigation to determine whether that population should be released in Roraima to control the pest.

Can Euseius alatus DeLeon (Acari: Phytoseiidae) prey on Aceria guerreronis Keifer (Acari: Eriophyidae) in coconut palm?

Mites of the genus Euseius are generally considered specialist as pollen feeders. Euseius alatus DeLeon is one of the six species of phytoseiid mites most commonly found on coconut plants in northeast Brazil associated with Aceria guerreronis Keifer. Although the morphology of E. alatus does not favor the exploitation of the meristematic area of the fruit inhabited by A. guerreronis, the predator may have some role in the control of this eriophyid during the dispersion process. The objective of this work was to evaluate the development and reproduction of E. alatus on the following diets: A. guerreronis, Ricinus communis pollen (Euphorbiaceae), and Tetranychus urticae Koch (Tetranychidae) + R. communis pollen + honey solution 10%. Euseius alatus developed slightly faster and had slightly higher oviposition rate when feeding on the diet composed of T. urticae + pollen + honey. However, life table parameters were very similar on all diets, suggesting that E. alatus may contribute in reducing the population of A. guerreronis in the field.

Mites on grapevines in northeast Brazil: occurrence, population dynamics and within-plant distribution

Mite pests are some of the major limiting factors affecting grape production in the world. Despite the economic importance of the grapevines and the damage to them caused by some of the phytophagous mites in northeast Brazil, little is known about the mite fauna associated with this crop. The present study aimed to identify the mite fauna associated with grapevine, to evaluate the fluctuation of the populations of the most frequent species of phytophagous mites and their associated predators over a 12-month period as well as their within-plant distribution. Considering all varieties sampled, Tetranychus urticae Koch and Oligonychus mangiferus (Rahman & Sapra) comprised 74% of phytophagous mites. Euseius citrifolius Denmark & Muma and Neoseiulus idaeus Denmark & Muma comprised more than 80% of Phytoseiidae mites. The population dynamics study was conducted in a vineyard of Sugraone and a vineyard of Itália Muscat varieties. In these fields, E. citrifolius occurred at low population levels throughout the year, whereas N. idaeus was found only when high densities of T. urticae were observed. Tetranychidae and Phytoseiidae showed the same pattern of within-plant distribution, being found in higher densities on basal and median leaves and rarely they were found on apical leaves.

The invasive red palm mite, Raoiella indica Hirst (Acari: Tenuipalpidae), in Brazil: range extension and arrival into the most threatened area, the Northeast Region

ABSTRACT Raoiella indica Hirst (Acari: tenuipalpidae), commonly known as the red palm mite (RPM), is an invasive polyphagous pest, which has emerged as a threat to agriculture in the Americas. In the Americas, the mite has not only spread quickly, but also greatly extended its host range in the new areas where it has been observed. We present here new records of the RPM in Brazilian states, with focus on its arrival into the most threatened area, the Northeast Region. Coconut and banana are important crops in this region of Brazil and represent the main threatened crops by this pest. These new records of RPM reinforce the idea that this species is already widely distributed throughout Brazil eight years after its introduction into the extreme North state of Roraima. Comments on the possible economic, social and environmental impacts are presented.