Distribution of Amblyseius manihoti (Acari, Phytoseiidae) on manioc and development of sampling plan

Sampling plans were developed for Amblyseius manihoti, a predator of the cassava green mite Mononychellus progresivus Doreste (Acari, Tetranychidae). Analysis of intra-plant distribution showed a more stable and constant distribution of A. manihoti on the leaves 9-12 (numbering starting from the first fully developed leaf), hence leaves belonging to this stratum were chosen as the sampling unit. Within this unit, A. manihoti displayed aggregated distributions between plants. The proposed binomial and the enumerative sampling procedures permitted reliable estimates of A. manihoti densities. For population monitoring, 100 sample units per field were sufficient to provide satisfactory estimates of densities.