Life history characteristics of Frankliniella occidentalis on cucumber leaves with and without supplemental food

Abstract

The development time, fecundity, longevity, and resultant intrinsic growth rate of the western flower thrips Frankliniella occidentalis (Pergande) [Thysanoptera: Thripidae] encaged on a cucumber leaf were compared among seven types of food supplied: six pollen species and a mixture of milk powder and yeast. The rationale was to find a food source that offers the least benefit for thrips and could therefore be considered as a food source for the preventative introduction of thrips predators. With the exception of the mixture of milk powder and yeast, all the food sources tested offered a nutritional benefit for the thrips. The addition of pollen increased fecundity and reduced development time, mainly during the larval stage. Betula pubescens and Corylus avellana pollen also increased adult longevity. The nutritional benefit of Pinus sylvestris pollen was greater than that of the other five pollen species, as manifested by its significantly greater positive effect on fecundity. The other pollen species could not be ranked in terms of nutritional benefit to F. occidentalis. The negative effect of the milk powder plus yeast mix on the life‐table parameters of F. occidentalis probably only occurs in an encaged situation where thrips cannot escape from the unfavorable environment. The crude estimate of the intrinsic growth rate of F. occidentalis increased from 0.163 on the plain cucumber leaf to 0.240 when P. sylvestris pollen was added to the leaf. The differences in intrinsic growth rate mainly reflect the differences in fecundity among the food sources. Thus, the peak oviposition rate may be used as a measure of the nutritional benefit F. occidentalis can obtain by feeding on supplemental food sources. The positive effect of a supplemental food source on thrips does not necessarily mean it is unsuitable for the preventative introduction of thrips predators, because the supplemental food can also affect the population dynamics of the predator and the predator–prey interaction and, hence, the outcome of biological control.

Sampling Techniques for Thrips (Thysanoptera: Thripidae) in Preflowering Tomato

“…In this study, the r value of F. occidentalis and F. intonsa was higher on cucumber leaves than that on tomato leaves, especially for F. intonsa, which is low to 0.01 on tomato leaf, this means the not suitable of tomato leaf for population development, but slowly population development would be improved in fields when added with pollens as reported in F. occidentalis (Gerin et al 1999, Hulshof et al 2003, Zhi et al 2005.…”

“…Although the important effect of pollens on individual growth and population development of flower visiting thrips, such as F. occidentalis (Hulshof et al 2003, Riley et al 2011, plant leaves also offered sufficient nutrition when flower were scare, e.g., F. occidentalis caused severe damage on the seedling stages and young leaves (Olson et al 2006), and in laboratory, the intrinsic rate of F. occidentalis on cucumber leaf were 0.3 in Gaum et al (1994) and 0.21 in Zhang et al (2007) as was 0.21 of F. intonsa in cucumber in this study which mean the suitability for population development of thrips. The plant leaves also be used to evaluate the performance of F. occidentalis on different plants and performance of F. occidentalis compared with other thrips such as F. bispinosa (Northfield et al 2011) andT.…”

Biologia e tabela de vida de fertilidade de Frankliniella occidentalis (Pergande) (Thysanoptera, Thripidae) em morangueiro

“…O alimento ingerido na fase larval afeta, não só o tempo de desenvolvimento, mas também o tamanho corporal do tripes. Assim, larvas maiores e mais rápidas são potencialmente menos suscetíveis a serem predadas por seus inimigos naturais (Gerin et al 1999;de Kogel et al 1999;Hulshof et al 2003).…”

“…Esta hipótese foi corroborada pelos resultados obtidos por Trichilo & Leigh (1988) e Hulshof et al (2003), os quais verificaram um aumento significativo na fecundidade de F. occidentalis quando o pólen foi adicionado à dieta. Em F. shultzei, Milne et al (1996) observaram o mesmo efeito.…”

Biological control of Echinothrips americanus by phytoseiid predatory mites and the effect of pollen as supplemental food

“…When pollen is applied as supplemental food for predatory mites, there is a potential risk of promoting pollen-feeding thrips under certain conditions, as pollen is also edible for this thrips (Hulshof et al 2003;Leman and Messelink 2015;van Rijn et al 2002;Vangansbeke et al 2016). Because E. americanus is a leaf-dwelling thrips species, it is not expected to feed on pollen.…”