Assessing abundance and distribution of an invasive thrips Frankliniella schultzei (Thysanoptera: Thripidae) in south Florida

Abstract

Within-plant and within-field distribution of larvae and adults of an invasive thrips species, Frankliniella schultzei (Trybom) on cucumber, Cucumis sativus L. was studied in 2008 and 2009 in Homestead, Florida. The majority of thrips were found inhabiting flowers of cucumber plants and little or none was found on the other parts of the plant. Thrips were aggregated in the field, as indicated by the two regression models, Taylor's power and Iwao's patchiness regression. Iwao's patchiness regression provided a better fit than Taylor's power law. The distribution was clumped during the initial stages of infestation at the edges of the field and became random thereafter. However, with increase in population density, thrips again formed aggregates in the field. Based on the average pest density per flower in a ∼0.25-ha field, minimum sample size (number of flowers) required at the recommended precision level (0.25) was 51. The number of samples required at two levels of predetermined pest density was also calculated, which would help growers in collecting optimum number of samples required to determine the correct threshold level of pest in fields. Results from seasonal abundance indicated that density of thrips peaked during the fifth week of sampling with an average of 25 and 34 adults per ten flowers during autumn 2008 and 2009, respectively. Results from these studies will help growers and extension personnel in understanding the abundance and distribution of F. schultzei in the field, which are important components required in developing a sound management program.

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

“…Generally, the common blossom thrips thrives well in areas with mild temperatures (Milne et al 1996;Kakkar et al 2012;Palmer et al, 1992) which were available in submontane (1200m -1600m a.s.l) and montane (1500-1799m a.s.l) zones at both Taita Hills and Mount Kilimanjaro agroecosystems. However, distribution patterns of Frankliniella schultzei along altitudinal gradient of Taita Hills and Mount Kilimanjaro may shift drastically in future with changing climate and associated agricultural activities.…”

“…Common blossom thrips (Frankliniella schultzei Trybom) is anthophilous pest species (Milne et al, 1996;Odanga et al, 2017b) whose diet is predominantly pollen and floral tissues (Kakkar et al, 2012). 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).…”

“…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.…”

New species for the Hungarian Thysanoptera fauna collected by suction trap

“…However, it also attacks tomato, sweet potato, coff ee, sorghum, chillies, onion and sunfl ower (Hill 1975). In South America and in Florida it is an important pest of tomato and cucumber in the fi eld (Monteiro et al 2001, Jones 2005, Kakkar et al 2012. Th e species can attack the plants directly (sucking, pollen feeding) but can be harmful indirectly as well, because it is one of the important vectors of TSWV (Tomato Spotted Wilt Virus) (Vierbergen & Mantel 1991, Wijkamp et al 1995, Riley et al 2011.…”

First record of Tomato chlorotic spot virus in the USA

“…Several TCSV vector species have existed in Florida for some time (Frantz & Fasulo, 1997). However, the dark form of Frankliniella schultzei, demonstrated in one study to be the most efficient vector of TCSV, has only recently become a pest in vegetable crops in South Florida (Wijkamp et al, 1995;Kakkar et al, 2012). It is possible that TCSV is a recent introduction possibly on an unknown ornamental host.…”