International Journal of Tropical Insect Science, 2016
Frankliniella schultzei Trybom is a polyphagous pest and vector of tospoviruses worldwide. It occ... more Frankliniella schultzei Trybom is a polyphagous pest and vector of tospoviruses worldwide. It occurs in dark and pale colour forms that are morphologically similar but differ in vector competency and geographic spread. In Kenya and other tropical regions, mixed populations of both colour forms are observed in similar habitats, so are considered as one species. To ascertain the taxonomic status of the two colour forms, they were characterized using morphological, molecular, biological and ecological approaches. Morphological characterization revealed differences between the colour forms on eight features and they separated into distinct clusters through principal component analysis. Restriction fragment length polymorphism of the internal transcribed spacer region (ITS-RFLP) analysis revealed differences between the two colour forms and was confirmed by differences in ITS2 sequences. Virgin pale females had female offspring (thelytoky), while virgin dark females had male offspring (a...
Thermothrips mohelensis Pelikán is an extremely rare thrips found in dry steppe grassland ecosyst... more Thermothrips mohelensis Pelikán is an extremely rare thrips found in dry steppe grassland ecosystems (Pelikán 1949, 1995; Ulitzka 2019a). It has been reported from only a few locations and almost always in very low abundance: one female each has been collected in Germany (Ulitzka 2019a), Slovenia (Kucharczyk 2008) and Turkey (Tunç 1992), two females are known from Iran (Mirab-balou & Chen 2013), three from Poland (Zawirska 1988; Kucharczyk 2007) and six from Western Russia (Schliephake 1977). Larger series including males and larvae are known only from Czechoslovakia (Pelikán 1949, 1995) and from Yakutia, East Siberia where—besides other specimens—the larvae discussed below have been collected (see Evdokarova & Kucharczyk 2020). The fragmented and selective occurrence of this species in steppe habitats has been interpreted to represent scattered relict populations that may have remained from a more extensive distribution far back, possibly in the wide dry grasslands of the Late Plei...
Parthenogenesis under influence of microbes in Thysanoptera. Several thrips species were tested f... more Parthenogenesis under influence of microbes in Thysanoptera. Several thrips species were tested for the presence of parthenogenesis-inducing bacteria of the genus Wolbachia using primers amplifying either the 16S rDNA gene or the ftsZ gene. Tested species show either arrhenotoky (Frankliniella occidentalis, Echinothrips americanus, Gynaikothrips ficorum, Suocerathrips linguis) or thelytoky (Hercinothrips femoralis, Parthenothrips dracaenae). In contrast, Thrips tabaci reproduces by arrhenotoky
ABSTRACT When attacked by a predator many Thysanoptera are able to bend their abdomen scorpion- l... more ABSTRACT When attacked by a predator many Thysanoptera are able to bend their abdomen scorpion- like and to place a defensive secretion on their enemies over the head (lewis 1973). Adults and larvae of the fungus-feeding Suocerathrips linguis MounD & Marullo, 1994 (Thysanoptera, Phlaeothripidae) produce also an anal secretion. Methanol extracts of droplets of adult males and females of S. linguis were examined using GC-MS. The samples yielded aliphatic alkanes and alkenes and long-chain acetates. The two main components, (11Z)-11,19-eicosadienyl acetate and stearyl acetate, already described by tschuch & al. (2005), were confirmed. The third substance in abundance is 17-octadecenyl acetate, which is otherwise not known to occur naturally. Oleyl acetate, 1-heptadecene and 1,9-nonadecadiene were identified by DMDS derivatization data. Oleyl acetate and 1,9-nonadecadiene were not found in thrips before. Furthermore heptadecane was detected (Gehlsen & al. 2009). Determination of configuration of the compounds was
ABSTRACT The influence of three different temperatures on developmental time and sex ratio was in... more ABSTRACT The influence of three different temperatures on developmental time and sex ratio was investigated in the bisexual Thysanoptera species Frankliniella occidentalis. Increasing temperatures decreased developmental time and induced a more female biased sex ratio. Remarkably, there are second instars with a prolonged developmental time requiring the same number of hours as the shortest developmental time from egg to adult. Arrhenotokous reproduction in this species is based on haplodiploidy, with virgin females producing male offspring exclusively. However, at all three temperatures tested, about 0.5% of offspring from unfertilized eggs were females. The presence of Wolbachia could not be detected in Western flower thrips and can be excluded as influencing reproduction in this species.
Mitteilungen Der Deutschen Entomologischen Gesellschaft, May 29, 2006
Apoptosis of the right mandible limb in Thysanoptera ontogeny - a twice recurring phenomenon. Thr... more Apoptosis of the right mandible limb in Thysanoptera ontogeny - a twice recurring phenomenon. Thrips exhibit a wide range of biology. Larvae and adult stages feed on the cells of angiosperms and gymnosperms, with a few on ferns and mosses and others predatory on small arthropods, but with many feeding only on fungal hyphae or spores. All larvae and adults
Male sexual aggregations are a common territorial, mating-related or resource-based, behaviour ob... more Male sexual aggregations are a common territorial, mating-related or resource-based, behaviour observed in diverse organisms, including insects such as thrips. The influence of factors such as plant substrate, time of day, and geographic location on aggregation of thrips is uncertain, therefore we monitored the dispersion of male and female bean flower thrips (BFT), Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae), on cowpea, Vigna unguiculata (L.) Walp. (Fabaceae), over three cowpea growth stages and across three cowpea-growing areas of Kenya. Our results indicated that for all the crop growth stages, the density of BFTs varied over the time of day, with higher densities at 10:00, 13:00, and 16:00 hours than at 07:00 hours. Thrips densities did not differ among blocks at the budding stage, but they did at peak flowering and podding stages. Dispersion indices suggested that both male and female BFTs were aggregated. Active male aggregation occurred only on green plant par...
ABSTRACT The genus Frankliniella Karny is the second largest in the family Thripidae with many po... more ABSTRACT The genus Frankliniella Karny is the second largest in the family Thripidae with many polyphagous thrips and tospovirus vectors which are Neotropic and Nearctic in origin. The invasive Western Flower Thrips (WFT), Frankliniella occidentalis (Pergande) and F. schultzei Trybom are known to occur in East Africa. However detailed information on the distribution and diversity of Frankliniella sp. is lacking in East Africa. Detailed surveys in over 250 locations were undertaken from August 2008 to July 2010. Both the dark and pale forms of WFT were found restricted to the high and mid altitude regions of Kenya. Frankliniella schultzei, the most widespread species was observed in high-, mid- and low altitude regions of East Africa. Both pale forms with short third ocellar setae (OSIII) and dark forms with long OSIII were observed in East Africa. Molecular analysis of the ITS1/ITS2 sequences of F. schultzei forms with RFLP technique indicated high degree of divergence between them. While WFT and F. schultzei were frequently pest on French beans, tomato and capsicum; the latter was also pest on potato, egg plant, cucurbits, amaranthus, pigeon pea etc. For the first time we observed the occurrence of Frankliniella williamsi Hood 1915 and Frankliniella borinquen Hood, 1942 from East Africa. While F. williamsi was frequently observed on graminaceous plants such as maize, sorghum, rice and wheat, F. borinquen was frequently observed on the weed,Tithonia diversifolia (Hemsl.) A Gray. Further detailed information on the plant-association, distribution will be presented in this paper.
International Journal of Tropical Insect Science, 2016
Frankliniella schultzei Trybom is a polyphagous pest and vector of tospoviruses worldwide. It occ... more Frankliniella schultzei Trybom is a polyphagous pest and vector of tospoviruses worldwide. It occurs in dark and pale colour forms that are morphologically similar but differ in vector competency and geographic spread. In Kenya and other tropical regions, mixed populations of both colour forms are observed in similar habitats, so are considered as one species. To ascertain the taxonomic status of the two colour forms, they were characterized using morphological, molecular, biological and ecological approaches. Morphological characterization revealed differences between the colour forms on eight features and they separated into distinct clusters through principal component analysis. Restriction fragment length polymorphism of the internal transcribed spacer region (ITS-RFLP) analysis revealed differences between the two colour forms and was confirmed by differences in ITS2 sequences. Virgin pale females had female offspring (thelytoky), while virgin dark females had male offspring (a...
Thermothrips mohelensis Pelikán is an extremely rare thrips found in dry steppe grassland ecosyst... more Thermothrips mohelensis Pelikán is an extremely rare thrips found in dry steppe grassland ecosystems (Pelikán 1949, 1995; Ulitzka 2019a). It has been reported from only a few locations and almost always in very low abundance: one female each has been collected in Germany (Ulitzka 2019a), Slovenia (Kucharczyk 2008) and Turkey (Tunç 1992), two females are known from Iran (Mirab-balou & Chen 2013), three from Poland (Zawirska 1988; Kucharczyk 2007) and six from Western Russia (Schliephake 1977). Larger series including males and larvae are known only from Czechoslovakia (Pelikán 1949, 1995) and from Yakutia, East Siberia where—besides other specimens—the larvae discussed below have been collected (see Evdokarova & Kucharczyk 2020). The fragmented and selective occurrence of this species in steppe habitats has been interpreted to represent scattered relict populations that may have remained from a more extensive distribution far back, possibly in the wide dry grasslands of the Late Plei...
Parthenogenesis under influence of microbes in Thysanoptera. Several thrips species were tested f... more Parthenogenesis under influence of microbes in Thysanoptera. Several thrips species were tested for the presence of parthenogenesis-inducing bacteria of the genus Wolbachia using primers amplifying either the 16S rDNA gene or the ftsZ gene. Tested species show either arrhenotoky (Frankliniella occidentalis, Echinothrips americanus, Gynaikothrips ficorum, Suocerathrips linguis) or thelytoky (Hercinothrips femoralis, Parthenothrips dracaenae). In contrast, Thrips tabaci reproduces by arrhenotoky
ABSTRACT When attacked by a predator many Thysanoptera are able to bend their abdomen scorpion- l... more ABSTRACT When attacked by a predator many Thysanoptera are able to bend their abdomen scorpion- like and to place a defensive secretion on their enemies over the head (lewis 1973). Adults and larvae of the fungus-feeding Suocerathrips linguis MounD & Marullo, 1994 (Thysanoptera, Phlaeothripidae) produce also an anal secretion. Methanol extracts of droplets of adult males and females of S. linguis were examined using GC-MS. The samples yielded aliphatic alkanes and alkenes and long-chain acetates. The two main components, (11Z)-11,19-eicosadienyl acetate and stearyl acetate, already described by tschuch & al. (2005), were confirmed. The third substance in abundance is 17-octadecenyl acetate, which is otherwise not known to occur naturally. Oleyl acetate, 1-heptadecene and 1,9-nonadecadiene were identified by DMDS derivatization data. Oleyl acetate and 1,9-nonadecadiene were not found in thrips before. Furthermore heptadecane was detected (Gehlsen & al. 2009). Determination of configuration of the compounds was
ABSTRACT The influence of three different temperatures on developmental time and sex ratio was in... more ABSTRACT The influence of three different temperatures on developmental time and sex ratio was investigated in the bisexual Thysanoptera species Frankliniella occidentalis. Increasing temperatures decreased developmental time and induced a more female biased sex ratio. Remarkably, there are second instars with a prolonged developmental time requiring the same number of hours as the shortest developmental time from egg to adult. Arrhenotokous reproduction in this species is based on haplodiploidy, with virgin females producing male offspring exclusively. However, at all three temperatures tested, about 0.5% of offspring from unfertilized eggs were females. The presence of Wolbachia could not be detected in Western flower thrips and can be excluded as influencing reproduction in this species.
Mitteilungen Der Deutschen Entomologischen Gesellschaft, May 29, 2006
Apoptosis of the right mandible limb in Thysanoptera ontogeny - a twice recurring phenomenon. Thr... more Apoptosis of the right mandible limb in Thysanoptera ontogeny - a twice recurring phenomenon. Thrips exhibit a wide range of biology. Larvae and adult stages feed on the cells of angiosperms and gymnosperms, with a few on ferns and mosses and others predatory on small arthropods, but with many feeding only on fungal hyphae or spores. All larvae and adults
Male sexual aggregations are a common territorial, mating-related or resource-based, behaviour ob... more Male sexual aggregations are a common territorial, mating-related or resource-based, behaviour observed in diverse organisms, including insects such as thrips. The influence of factors such as plant substrate, time of day, and geographic location on aggregation of thrips is uncertain, therefore we monitored the dispersion of male and female bean flower thrips (BFT), Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae), on cowpea, Vigna unguiculata (L.) Walp. (Fabaceae), over three cowpea growth stages and across three cowpea-growing areas of Kenya. Our results indicated that for all the crop growth stages, the density of BFTs varied over the time of day, with higher densities at 10:00, 13:00, and 16:00 hours than at 07:00 hours. Thrips densities did not differ among blocks at the budding stage, but they did at peak flowering and podding stages. Dispersion indices suggested that both male and female BFTs were aggregated. Active male aggregation occurred only on green plant par...
ABSTRACT The genus Frankliniella Karny is the second largest in the family Thripidae with many po... more ABSTRACT The genus Frankliniella Karny is the second largest in the family Thripidae with many polyphagous thrips and tospovirus vectors which are Neotropic and Nearctic in origin. The invasive Western Flower Thrips (WFT), Frankliniella occidentalis (Pergande) and F. schultzei Trybom are known to occur in East Africa. However detailed information on the distribution and diversity of Frankliniella sp. is lacking in East Africa. Detailed surveys in over 250 locations were undertaken from August 2008 to July 2010. Both the dark and pale forms of WFT were found restricted to the high and mid altitude regions of Kenya. Frankliniella schultzei, the most widespread species was observed in high-, mid- and low altitude regions of East Africa. Both pale forms with short third ocellar setae (OSIII) and dark forms with long OSIII were observed in East Africa. Molecular analysis of the ITS1/ITS2 sequences of F. schultzei forms with RFLP technique indicated high degree of divergence between them. While WFT and F. schultzei were frequently pest on French beans, tomato and capsicum; the latter was also pest on potato, egg plant, cucurbits, amaranthus, pigeon pea etc. For the first time we observed the occurrence of Frankliniella williamsi Hood 1915 and Frankliniella borinquen Hood, 1942 from East Africa. While F. williamsi was frequently observed on graminaceous plants such as maize, sorghum, rice and wheat, F. borinquen was frequently observed on the weed,Tithonia diversifolia (Hemsl.) A Gray. Further detailed information on the plant-association, distribution will be presented in this paper.
Uploads