Feeding and breeding across host plants within a locality by the widespread thrips Frankliniella schultzei, and the invasive potential of polyphagous herbivores

Abstract

Abstract. Polyphagous insect herbivores could be expected to perform relatively well in new areas because of their ability to exploit alternative resources. We investigated relative abundance patterns of the polyphagous thrips species Frankliniella schultzei, which is characteristically found on plants from many different families, to establish the role of different host plant species in a single locality where the species is not indigenous (Brisbane, south‐eastern Queensland, Australia). F. schultzei females and larvae were always present in flowers (where oviposition takes place) and never on leaves of the eight plant species that we surveyed regularly over one year. They were present in flowers of Malvaviscus arboreus in much higher densities than for any other host. F. schultzei females were more fecund and larvae developed faster on floral tissue diets of M. arboreus than on those of other hosts. M. arboreus is therefore regarded as the ‘primary’ host plant of F. schultzei in the locality that we investigated. The other species are regarded as ‘minor’ hosts. Available evidence indicates a common geographical origin of F. schultzei and M. arboreus. F. schultzei may therefore be primarily adapted to M. arboreus. The flowers of the minor species on which F. schultzei is also found may coincidentally share some features of the primary host. Adult thrips may therefore accumulate on minor hosts and breed there, but to a lesser extent than on the primary host. The general implications for investigating polyphagous host relationships and interpreting the ecology of these species as generalist invaders are spelt out.

Australian Thysanoptera – biological diversity and a diversity of studies

“…In Australia, the introduced species Frankliniella schultzei is abundant around Brisbane within the rolled petals of the South American shrub, Malvaviscus arboreus. This plant has thus been referred to as the 'primary' host of this thrips (Milne & Walter 2000), and the other plants on which it is found around Brisbane as 'minor' hosts. However in other parts Australia, very large populations of F. schultzei occur on a wide range of non-native plants in the absence of Malvaviscus.…”

Spatial characterization of common blossom thrips (Frankliniella schultzei) in smallholder avocado orchards along slopes of Taita Hills and Mount Kilimanjaro

“…Being a polyphagous insect pest, it feeds on flowers of various ornamental, vegetable and fruit crop hosts in different parts of the world (Milne et al, 1996;Kakkar et al, 2012). Palmer (1990), Palmer (1992) and Milne & Walter (2000) reported Frankliniella schultzei on 83 species of plants from 35 families with important hosts being cotton (Gossypium spp. ), groundnut (Arachis hypogaea), beans (Phaseolus vulgaris) and pigeon pea (Cajanus cajan) and avocado (Persea americana).…”

Relative host plant species use by the lantana biological control agent Aconophora compressa (Membracidae) across its native and introduced ranges

“…Primary hosts are those that have the herbivore species of interest present on them most regularly and in relatively high numbers, and such hosts are predicted to have the entire range of features (stimuli) by which these herbivores detect, localise and use host plants (Walter and Benfield, 1994;Rajapakse et al, 2006). Secondary and incidental host plant species are predicted to have only a subset of these features and so are used less regularly in the field and in relatively lower numbers (Walter and Benfield, 1994;Milne and Walter, 2000;Walter, 2003, Chapter 7;Rajapakse et al, 2006).…”