Population dynamics of Aceria guerreronis (Acari: Eriophyidae) and its predatory mite, Neoseiulus baraki (Acari: Phytoseiidae) in two coconut growing areas in Sri Lanka

Abstract

Densities of coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae) and its predatory mite, Neoseiulus baraki Athias-Henriot (Acari: Phytoseiidae) were monitored on coconut fruits in two coconut mite infested areas, Kalpitiya and Madurankuliya, in Sri Lanka, over a period of 3 years and were compared with local rainfall records. Significant differences in A. guerreronis densities were observed among years and months of the year. Rainfall (amount and frequency, i.e. the total number of days with rainfall of >5 mm) was not significantly correlated with the variation of A. guerreronis densities. But the drought length (i.e. the number of days without rainfall of >5 mm) significantly influenced A. guerreronis densities. Generally, peak densities of A. guerreronis were observed during February-March and June-September in both areas. The differences in the N. baraki densities were significantly different between the two areas and among the 3 years but not among months of the year. Although the amount of rainfall was not significantly correlated with the population densities of N. baraki, frequency of rainfall showed a negative significant correlation and drought length showed a positive significant correlation with the population densities. The results of this experiment indicated that the application of control methods for A. guerreronis may be more advantageous if they are carried out at the onset and during the dry seasons.

Mite species (Acari) on blackberry cultivars in organic and conventional farms in Florida and Georgia, USA

“…In contrast, no mite was found on the leaf samples taken from the Freedom cultivar, and 4). We hypothesize that differences in mite numbers and diversity may be caused by different phytochemical components, morphological and histological leaf structure of blackberry cultivars as stated by Camporese and Duso (1996), Krips et al (1999), Kretier et al (2002, Kabicek (2008), Khan et al (2008) and Ali et al (2015) for different plants. It should be noted that a single factor is not responsible for the abundance and diversity of mites but a combination of factors.…”