Determination of beginning of bulb enlargement time in shallot, Allium cepa var aggregatum for managing onion thrips ( Thrips tabaci )

2017 ◽  
Vol 220 ◽  
pp. 154-159 ◽  
Author(s):  
Tebkew Damte ◽  
Getachew Tabor ◽  
Mesfin Haile ◽  
Geteneh Mitiku ◽  
Tewodros Lulseged
Keyword(s):  
Allium Cepa ◽  
Thrips Tabaci ◽  
Onion Thrips

scholarly journals Investigations of Thrips tabaci and Aeolothrips intermedius population dynamics in tobacco plantations

2018 ◽  
pp. 121-127
Author(s):  
Szilvia Orosz ◽  
László Bujdos ◽  
Lajos Varga ◽  
Tibor Fekete
Keyword(s):  
Population Dynamics ◽  
Primary Objective ◽  
Thrips Tabaci ◽  
Onion Thrips ◽  
Sticky Traps ◽  
Chemical Treatments ◽  
Proper Timing ◽  
Yellow Sticky Traps

Studies were conducted between 2015 and 2017 with yellow sticky traps in seven tobacco plantations. The purpose was to determine when and in what numbers onion thrips individuals can settle into tobacco plantations. The primary objective of the study was to determine the proper timing of chemical treatments, furthermore, the determination of crucial factors that can influence the population dynamics of Thrips tabaci.

scholarly journals Thrips (Thysanoptera) associated with onion (Allium cepa L.) and Welsh onion (Allium fistulosum L.)

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Marta Olczyk ◽  
Maria Pobożniak
Keyword(s):  
Allium Cepa ◽  
Growing Season ◽  
Thrips Tabaci ◽  
Allium Fistulosum ◽  
Onion Thrips ◽  
Welsh Onion ◽  
Allium Cepa L ◽  
Onion Cultivar ◽  
The Relationship ◽  
Thrips Population

AbstractWe determined the abundance, species composition, sex ratio and seasonal dynamics of thrips on one cultivar of Welsh onion (Allium fistulosum) and eight cultivars of onion (Allium cepa) in South Poland within three vegetation seasons (2014–2016). Nine species of Thysanoptera were identified on A. cepa and A. fistulosum. Irrespective of the onion cultivar, Thrips tabaci was the dominant species (64.4% of all collected thrips specimens), while Frankliniella intonsa also occurred in high numbers (28.3%). Conversely, Welsh onion was most often inhabited by F. intonsa (62.7%), although T. tabaci was also numerous (28.3%). The predatory Aeolothrips intermedius accounted for 4.5% on A. cepa and 2.9% on A. fistulosum. In the most numerous species, T. tabaci, F. intonsa and A. intermedius populations were formed mainly by females. The cultivar most colonised by thrips was Kroll of A. fistulosum. The tested cultivars of A. cepa demonstrated varying degrees of attractiveness to thrips in the subsequent years. The relationship between populations of T. tabaci, F. intonsa and A. intermedius changed in the subsequent months of the growing season. In June, mainly T. tabaci and F. intonsa occurred on onion plants, while from July, the percentage shares of F. intonsa and the predatory A. intermedius in the thrips population on many onion cultivars increased. The level of attractiveness of A. cepa related to onion thrips, which is reported as a main pest of onion, varies depending on the year and cultivar.

scholarly journals Insects’ RNA Profiling Reveals Absence of “Hidden Break” in 28S Ribosomal RNA Molecule of Onion Thrips,Thrips tabaci

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Rosaline Wanjiru Macharia ◽  
Fidelis Levi Ombura ◽  
Erick Onyango Aroko
Keyword(s):  
Ribosomal Rna ◽  
Thrips Tabaci ◽  
28S Rrna ◽  
Onion Thrips ◽  
Rna Integrity ◽  
Rna Profiling ◽  
Insect Order ◽  
Banding Profile ◽  
Rrna Sequences

With an exception of aphids, insects’ 28S rRNA is thought to harbor a “hidden break” which cleaves under denaturing conditions to comigrate with 18S rRNA band to exhibit a degraded appearance on native agarose gels. The degraded appearance confounds determination of RNA integrity in laboratories that rely on gel electrophoresis. To provide guidelines for RNA profiles, RNA from five major insect orders, namely, Diptera, Hemiptera, Thysanoptera, Hymenoptera, and Lepidoptera, was compared under denaturing and nondenaturing conditions. This study confirmed that although present in most of insect’s RNA, the “hidden break” is absent in the 28S rRNA of onion thrips,Thrips tabaci. On the other hand, presence of “hidden break” was depicted in whiteflies’ 28S rRNA despite their evolutionary grouping under same order with aphids. Divergence of 28S rRNA sequences confirms variation of both size and composition of gap region among insect species. However, phylogeny reconstruction does not support speciation as a possible source of the hidden break in insect’s 28S rRNA. In conclusion, we show that RNA from a given insect order does not conform to a particular banding profile and therefore this approach cannot be reliably used to characterize newly discovered species.

Evaluation of UV reflective mulches for protection against thrips (Thrips tabaci) in onion (Allium cepa) crops

2004 ◽  
Vol 57 ◽  
pp. 209-213
Author(s):  
R.F. Van_Toor ◽  
C. Till ◽  
D.E. James ◽  
D.A.J. Teulon
Keyword(s):  
Allium Cepa ◽  
Field Trial ◽  
Late Summer ◽  
Bare Soil ◽  
Thrips Tabaci ◽  
Aluminium Foil ◽  
Plastic Mulch ◽  
Onion Thrips

The efficacy of the ultraviolet (UV) reflective plastic mulch Extenday for preventing onion thrips (Thrips tabaci) from colonising onions was evaluated The mulch reflected 35 of incident UV at 250 nm wavelength and 25 of incident UV at 360 nm while bare soil reflected 11 and 4 UV at these wavelengths respectively In a field trial the total number of thrips at 8 weeks after transplanting was lower with mulch (185 thrips/ bulb) than in the control (280 thrips/bulb) However thrips populations were similar for both treatments in subsequent assessments When onions in seedling trays were placed adjacent to an onion field for 818 days during early mid and late summer aluminium foil which reflected UV 250 nm by 43 and UV 360 nm by 35 and Extenday did not reduce numbers of T tabaci compared to the control The use of reflective mulches for repelling thrips in onions does not appear promising

scholarly journals Biological parameters of onion thrips, Thrips tabaci Lindeman on onion cultivars

2017 ◽  
Vol 57 (2) ◽  
pp. 120-128 ◽  
Author(s):  
Maher Ahmed Moraiet ◽  
Mohammad Shafiq Ansari ◽  
Rabiya Basri
Keyword(s):  
Integrated Pest Management ◽  
Pest Management ◽  
Allium Cepa ◽  
Life Tables ◽  
Thrips Tabaci ◽  
Life Stages ◽  
Biological Parameters ◽  
Onion Thrips

Abstract Biological parameters of the onion thrips, Thrips tabaci Lindeman were studied on the following onion (Allium cepa L.) cultivars: Nasik Red Plus N-53, Onion Dr-301 (Krishna), Onion White, and Nasik Red, at 25±1°C and 65±5% RH. Significant (p < 0.05) differences were found in the life stages and fertility life tables on different cultivars except in the pupal stages. More information about the biological parameters of T. tabaci on onion cultivars can help in designing Integrated Pest Management programs for onion thrips.

Eliminating Thrips in Microshoot Cultures

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 506d-506
Author(s):  
Robert R. Tripepi ◽  
Holly J. Schwager ◽  
Mary W. George ◽  
Joseph P. McCaffrey
Keyword(s):  
Betula Pendula ◽  
Culture Media ◽  
Dry Weight ◽  
Thrips Tabaci ◽  
Shoot Cultures ◽  
Onion Thrips ◽  
Ulmus Americana ◽  
Shoot Height ◽  
Tissue Culture Media ◽  
Plant Tissue Cultures

Two insecticides, acephate or azadirachtin, were added to tissue culture media to determine their effectiveness in controlling onion thrips (Thrips tabaci Lindeman.) and to determine if these insecticides could damage the plant shoot cultures. To test for insecticide phytotoxicity, microshoots from European birch (Betula pendula), American elm (Ulmus americana), `Pink Arola' chrysanthemum (Dendranthema grandiflora), `America' rhododendron (Rhododendron catawbiense), `Golden Emblem' rose (Rosa hybrida), and `Gala' apple (Malus domestica) were placed in 130-ml baby food jars containing 25 ml of medium supplemented with 6.5, 13, or 26 mg/l Orthene® (contained acephate) or 0.55, 1.1, or 2.2 ml/l Azatin® (contained azadirachtin). Control jars lacked insecticide. To test for thrips control, 13 mg/l Orthene® or 0.55 ml/l Azatin® was added to Murashige and Skoog medium, and 10 thrips were placed on `Gala' apple microshoots in each jar. Jars were sealed with plastic wrap. In both studies, microshoot dry weight and heights were determined. In the second study, the total number of thrips per jar was also determined 3 weeks after inoculation. Microshoots on Orthene®-treated media lacked phytotoxicity symptoms, regardless of the concentration used. In contrast, Azatin® hindered plant growth, decreasing shoot height or dry weight by up to 85% depending on the species. Both insecticides prevented thrips populations from increasing, since less than 10 thrips were found in jars with insecticide-treated medium. Control jars, however, contained an average of almost 70 thrips per jar. This study demonstrated that both Orthene® and Azatin® were effective for eradicating thrips from plant tissue cultures, but Orthene® should probably be used because Azatin® was phytotoxic to all species tested.

Sign in / Sign up

Export Citation Format

Share Document