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The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is an important pest of cotton that also feeds on other crops and many wild hosts. In the mid-South, where tarnished plant bugs in cotton are controlled exclusively with synthetic insecticides, infestations resulted in >29% of all yield loss attributed to insect damage and the control costs exceeded US$10 per acre in 2013. They have developed resistance to the most commonly used insecticides. Estimations of gene flow and migration are important to understand the spread of resistance in tarnished plant bug populations. Here, we analyzed tarnished plant bugs collected from July to September, 2006, to estimate population genetic parameters using 13 microsatellite markers. Our data indicated that tarnished plant bug populations in the study area had undergone a population bottleneck and all loci deviated from Hardy–Weinberg equilibrium in one or more collections. Bayesian simulations and factorial correspondence analysis indicated the presence of two genetic clusters in the tarnished plant bug populations in the study area. Proportions of insects separated into the two genetic clusters changed from July to September. Genetic differentiation and reduced gene flow between populations were also observed. We postulate that while random genetic drift and gene flow may have contributed to the seasonal variations observed in the study populations, selection by insecticide sprays in cotton during 2005–2006 as well as other extrinsic factors could also have played a significant role in the temporal variation in genetic structure observed in the tarnished plant bug populations. [ABSTRACT FROM PUBLISHER]

Abstract: The complete genome sequence of a single-stranded RNA virus infecting the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), was identified by sequencing cDNA prepared from insects collected from the Mississippi Delta. The 9655 nucleotide positive-sense single-stranded RNA genome of the L. lineolaris single-stranded RNA virus (LyLV-1) contained a single open reading frame of 8958 nucleotides encoding a 2986 amino acid genome polypeptide. The open reading frame was flanked by untranslated regions of 603 and 69 nucleotides at the 5′- and 3′- ends of the genome, respectively. Database searches and homology based modeling was used to identify four capsid proteins (VP1-VP4), helicase/AAA-ATPase, cysteine protease (C3P), protease 2A, and the RNA-directed RNA polymerase (RdRp). In addition, a region with weak similarity to the eukaryotic structural maintenance of chromosome (SMC) domain was identified near the amino-terminal of the polyprotein and adjacent to the VP1 domain. The amino acid sequence of LyLV-1 was approximately 44.4% similar to that of sacbrood virus (SBV) of the honey bee. The genomic organization of both viruses showed remarkable similarity with the exception of highly divergent amino acid regions flanking fairly conserved structural and non-structural polypeptide regions. High similarity to the SBV genome and similarities in the genome organization and amino acid sequence with the viruses of the family Iflaviridae suggested that LyLV-1 was a novel member of this family. Virus particles were 39nm in diameter and appeared to transmit vertically via eggs. Although this virus may only cause covert infections under normal conditions, the potential for using this virus in biological control of L. lineolaris is discussed. [Copyright &y& Elsevier]

The article focuses on a study related to the evaluation of the effect of modification of the NI artificial diet on the biological fitness parameters of mass reared western tarnished plant bug Lygus hesperus. It discusses the investigation of three modifications including D1, D2 and D3 of the NI diet that avoids the cooked egg and improves mass fitness parameters of the hesperus. The study found an increase in production capacity and a reduction in production costs with the use of this diet.