A comparison of internal and external lipids of nondiapausing and diapause initiation phase adult Colorado potato beetles, Leptinotarsa decemlineata

Abstract

The Colorado potato beetle, Leptinotarsa decemlineata, reared under diapause-inducing conditions will emerge from the soil as an adult and enter the diapause initiation phase, a period where metabolic reserves are stockpiled before the beetles enter the nonfeeding diapause maintenance phase. Internal and external lipids were characterized during the diapause initiation phase (IP) and compared to the lipid profiles of nondiapausing adults. The primary internal lipids of both diapause IP and nondiapausing adults are triacylglycerols. Only trace amounts of internal lipids were detected in day 1 diapause IP adults. A dramatic increase in internal lipids was observed between day 7 and day 15 post-emergence in the diapause IP adults. The majority of the triacylglycerol isomers were identified as C50, C52 and C54 chain lengths by GC-MS. There were no observed differences in the isomeric distribution of the major internal lipids between diapause IP and nondiapausing adults. External lipids were mainly methyl-branched alkanes containing a 25 to 53 carbon backbone. The quantity of external lipids increased from day 1 to day 7 post-emergence in both the diapause IP and nondiapausing adults, with the bulk of the increase occurring in the longer chain-length methylalkanes.

Differences in the pre‐diapause and pre‐oviposition accumulation of critical nutrients in adult females of the beetle Colaphellus bowringi

“…diapause and reproductive female C. bowringi. Many previous studies, including those on Drosophila melanogaster Meigen (Ohtsu et al, 1992), Leptinotarsa decemlineata (Say) (Yocum et al, 2011), Culex pipiens L. (Sim & Denlinger, 2013), and Cameraria ohridella Deschka & Dimic (Weyda et al, 2015), have also found that the fat body is the major TAG storage site, and that diapausing females store more TAG than reproductive ones. TAG accumulated in the fat body during diapause preparation plays an important role in maintaining the diapause process (Hahn & Denlinger, 2011).…”

Molecular Organization of the Nanoscale Surface Structures of the Dragonfly Hemianax papuensis Wing Epicuticle

“…alcohols and carboxylic acids) were converted to trimethylsilyl (TMSi) derivatives by means of reaction with N,N-bis-trimethylsilyl-triflouro-acetamide (BSTFA, C 8 H 21 NOSi 2 ) in the presence of pyridine for 45 minutes at 70°C according to previously optimized laboratory protocols [8], [9], [21], [31]–[33]. The composition of the sample extract was determined by injecting 1 µL of the solution onto a capillary GC column (Rxi-5SIL MS column fused silica; column 30.0 m, 0.25 mm i.d., df = 0.25 µm, Restek Corporation, Bellefonte PA, U.S.A.), using He as the carrier gas at constant flow of 1.4 mL min −1 and a mass spectrometric detector (GCMS-QP2010, Shimadzu Scientific Instruments, Columbia, U.S.A).…”

“…Superhydrophobic and self-cleaning surfaces are of particular interest in these studies [2], [8], [9]. Recently, it was reported that the wings of several species of insects not only possess superhydrophobic and self-cleaning properties, but also possess strong antibacterial activity [10].…”

“…Most previous chemical characterizations of insect epicuticle and/or procuticle (the thicker layer below the epicuticle) physiologies have been performed in (macro) biological contexts [3], [5], [8], [20]–[22]. These studies are typically limited to broad classifications (e.g., waxy compounds) of the insect cuticle and certainly do not examine the specific composition of the epicuticle nanoscale structures [9], [23]–[26]. There is also a lack of knowledge regarding the nature and function of the structural components of the epicuticle and the procuticle.…”

Fatty Acid Composition of Sexes and Body Parts in a Solitary Wasp, Sphex flavipennis (Insecta: Hymenoptera)

“…Many insect species belonging to different orders have been investigated in terms of fatty acid contents so far (Barlow, 1964;Fast, 1964;Thompson, 1973;Thompson and Barlow, 1974;Nurullahoğlu et al, 2004;Stewart-Jones et al, 2009;Yocum et al, 2011;Sushchik et al, 2013;Gołebiowski et al, 2013). In some of these studies it was stated that fatty acid composition in insects may differ between sexes and even different developmental stages of the same species (Sushchik et al, 2013;Gołebiowski et al, 2013).…”