Ecobiology of Anaphothrips obscurus, a new dweller of citrus orchards brought in by more sustainable pest management practices

Abstract

1 The abundance and frequency of Anaphothrips obscurus (Thysanoptera: Thripidae) increased in a cover of Festuca arundinacea (Poaceae) when this plant was used to improve the biological control of the clementine key pest Tetranychus urticae (Acari: Tetranychidae).

2 To unveil the ecological role of A. obscurus in this system, we re-explored field data and performed laboratory studies aiming to determine its demographic parameters and feeding habits, as well as its role as a prey of predatory mites (Acari: Phytoseiidae) occurring in the Spanish citrus agreoecosystem.

3 Field studies indicate that T. urticae populations decreased, whereas those of A. obscurus and phytoseiids, as a whole, increased.

4 Reproductive and demographic parameters of macropterous and brachypterous morphs of A. obscurus were different and confirmed the host status of F. arundinacea.

5 Anaphothrips obscurus could compete with T. urticae as a result of its higher intrinsic rate of increase in F. arundinacea. However, A. obscurus zoophagy on T. urticae eggs and the host status of citrus can be discarded.

6 Anaphothrips obscurus can be a prey for Euseius stipulatus, Neoseiulus barkeri and Neoseiulus californicus (three phytoseiids preying on T. urticae), suggesting that apparent competition between A. obscurus and T. urticae could occur in citrus orchards.