Biological Parameters ofScirtothrips dorsalis(Thysanoptera: Thripidae) on Selected Hosts

Abstract

Since its establishment in Florida in 2005, Scirtothrips dorsalis Hood, a highly polyphagous species, has become an economically important pest of ornamental plants and a potentially significant pest of vegetable and fruit crops. Fruit and vegetable production in Florida is trending toward significant adoption of organic methods and use of widely dispersed small fields in rapidly urbanizing landscapes. Landscape plants may serve as refugia from which S. dorsalis recruits can disperse to nearby fruit and vegetable plantings. Therefore, information on this pest's biology including how it is affected by various host species is needed to develop effective integrated pest management (IPM) programs. In the greenhouse and laboratory condition, we studied the effects of various host plants, development, diel flight activity, oviposition, and demographics of S. dorsalis. The pest preferred Jalapeño pepper and Knockout rose over the other hosts, and it was most active between 1000 and 1600 hours EST. Irrespective of the host species, the duration of each of the immature stadia varied within a narrow range, and their respective sizes were quite similar. Demographic parameters quantified included gross reproduction rate (GRR), net reproductive rate (R(o)), intrinsic rate of increase per day (R(m)), finite rate of increase per day (λ), and mean generation time (T). The pest population may increase by a factor of ≈ 1.09/d, so that it may double in 8 or 9 d. The above information should be helpful in the development of sound programs to manage S. dorsalis on various crops and in the formulation of detection strategies by quarantine officers.

Development and Survivorship of Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) in Different Growth Stages of Mango and Selected Weeds

“…Chen, Lin, Chiu, & Shih (2013) and Kang, Lee, & Kim (2015) found that the development of S. dorsalis on mango decreased from 21.5, 14.8, 12.1, to 9.8 days at 20, 24, 28, and 32 °C , respectively. Seal, Klassen, & Kumar (2010) found that host as factor determined the developmental duration of S. dorsalis reared on bean, eggplant, pepper, rose, squash and tomato in a constant temperature of 26 °C had a mean duration of 20.3 ± 0.3; 19,9 ± 0,6; 17.8 ± 0.3; 18.8 ± 0.4; 20.2 ± 0.5 and 20.6 ± 0.3 days, respectively.…”

“…The laid down mango leaf inside the Petri dish was infested with ten female adult of S. dorsalis for 24 hours for oviposition. The upper part of the leaves was observed every four hours for the emergence of first larval instar (Seal, Klassen, & Kumar, 2010). The twenty newly hatches larval instars were transferred to new leaves.…”

Scientific Opinion on the pest categorisation of Scirtothrips dorsalis

“…The genetic differences between these samples was considered to be too great to support the conclusion that separate host races were present. According to Seal et al (2010), different populations of this pest have host preferences without substantial modifications to life history traits such as development, survival and fecundity. Toda et al (2014) found a new strain of S. dorsalis infesting capsicum in addition to mango and tea in Japan.…”

“…Given the high polyphagy of S. dorsalis, many wild plant species can serve as a reservoir for dispersal to cultivated plants (Seal et al, 2010). The availability of the host plants significantly increases the success of dispersal.…”

“…Host plants for these viruses are not grown in the EU. The pest's capacity also to vector tomato spotted wilt virus (TSWV) remains under discussion (Seal et al, 2010). However, a new strain of S. dorsalis infesting capsicum, and also mango and tea, in Japan was identified as a potential vector of TSWV in capsicum (Toda et al, 2014).…”