Population fluctuation and distribution of Brevipalpus phoenicis (Geijskes) (Acari: Tenuipalpidae) on peduncle, sepals and exocarp of guava (Psidium guajava L.) fruits of different ages.

Population fluctuation and distribution of Brevipalpus phoenicis in interaction with guava (Psidium guajava) fruit development are important ecological and phenological aspects to be considered in appropriate pest management. The study was carried out at the experimental orchard of Centro Fruticola del Zulia, Mara Co., Venezuela (10° 49' 98"LN, 71° 46' 33"LW), under annual mean temperature, relative humidity and potential evapotranspiration of 27°C, 73% and 2100 mm respectively. Twenty plants of guava were randomly selected; ten fruits plant -1 of 14, 21, 28, 35, 49, 56 and 84 days old (DPA: Days Post Anthesis) were harvested for mite counting on abaxial and adaxial surfaces of sepals, peduncles and around exocarp. Mean mite population fluctuated from 0 to 19 during the 84 DPA. Mites were more abundant on sepals and peduncle of young fruits, which were between 14 and 35 DPA, whereas on older fruits of 49 and 84 DPA the population density was more abundant around the exocarp. The highest mean (19.16 mites) population was observed on the abaxial surface of sepals, whereas the lowest mean (0) was found on the peduncle of old fruit, as well as on the adaxial surface of sepals when the fruit was 84 DPA. This population behavior is related to feeding habits of B. phoenicis since sepals provide the conditions for population increase in young fruits, probably due to special nutrition and protection from other mite predators, besides the anatomical characters of those structures facilitate the feeding and defense of this mite species.