Tarnished Plant Bug Research Articles

Temporal and Spatial Genetic Variability Among Tarnished Plant Bug (Hemiptera: Miridae) Populations in a Small Geographic Area

ABSTRACT 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 p...

Remote Sensing of Selected Winter and Spring Host Plants of Tarnished Plant Bug (Heteroptera: Miridae) and Herbicide Use Strategies as a Management Tactic

Remote sensing was used in a series of experiments over a three-year period to obtain spectral reflectance data for studying differences in vegetation indices between grasses, broadleaf plants, and grass/broadleaf plant mixtures. Selected non-crop winter and spring host plants of tarnished plant bug, Lygus lineolaris, were planted in field-plot experiments. Multispectral reflectance data were aerially acquired with both a Real-Time Digital Airborne Camera System (RDACS) sensor and Geospatial Systems (Duncan Tech) MS-2100 multispectral camera. The following six vegetation indices of spectral reflectance were evaluated in this study: normalized difference vegetation index, ratio vegetation index, green normalized difference vegetation index, green vegetation index, green ratio vegetation index, and Ashburn vegetation index. Vegetation indices calculated with imagery data for the grasses and broadleaves differed significantly; there appeared to be more discriminating differences between vegetation indices for grasses and broadleaf plants when the indices were based on a combination of green and near infrared or green and red spectral bands than when the indices were based on red and near infrared spectral bands. Insect data from these studies confirm that tarnished plant bug prefers broadleaf host plants, but can use Italian ryegrass for food and reproduction. The narrow temporal window of host suitability for Italian ryegrass may limit its significance. Herbicide destruction of broadleaf host plants in early spring prevented the tarnished plant bug population increases that occurred in untreated plots. Findings of this study would be useful in site-specific vegetation management decisions in programs such as the prototypical area-wide tarnished plant bug management experiment conducted in the Delta region of Mississippi.

Molecular Cloning and Characterization of G Alpha Proteins from the Western Tarnished Plant Bug, Lygus hesperus.

The Gα subunits of heterotrimeric G proteins play critical roles in the activation of diverse signal transduction cascades. However, the role of these genes in chemosensation remains to be fully elucidated. To initiate a comprehensive survey of signal transduction genes, we used homology-based cloning methods and transcriptome data mining to identity Gα subunits in the western tarnished plant bug (Lygus hesperus Knight). Among the nine sequences identified were single variants of the Gαi, Gαo, Gαs, and Gα12 subfamilies and five alternative splice variants of the Gαq subfamily. Sequence alignment and phylogenetic analyses of the putative L. hesperus Gα subunits support initial classifications and are consistent with established evolutionary relationships. End-point PCR-based profiling of the transcripts indicated head specific expression for LhGαq4, and largely ubiquitous expression, albeit at varying levels, for the other LhGα transcripts. All subfamilies were amplified from L. hesperus chemosensory tissues, suggesting potential roles in olfaction and/or gustation. Immunohistochemical staining of cultured insect cells transiently expressing recombinant His-tagged LhGαi, LhGαs, and LhGαq1 revealed plasma membrane targeting, suggesting the respective sequences encode functional G protein subunits.

IPM-CPR for peaches: incorporating behaviorally-based methods to manage Halyomorpha halys and key pests in peach.

The invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), has emerged as a key pest in mid-Atlantic peach production. Current management of H. halys has disrupted IPM programs by relying exclusively on frequent, repeated, season-long insecticide applications. We developed a behaviorally-based tactic termed IPM-CPR (Crop Perimeter Restructuring) that utilizes border sprays for H. halys, groundcover management for Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae) and mating disruption for Grapholita molesta (Busck) (Lepidoptera: Tortricidae). IPM-CPR reduced insecticide usage by 25-61%. Generally there was less, and at times significantly less, catfacing injury (attributable to H. halys) in peaches in the IPM-CPR blocks relative to the standard, and minimal differences in injury due to G. molesta or L. lineolaris. These results suggest that perimeter applications of insecticides exploit the border-arrestment behavior of H. halys by controlling them at the orchard edge, reducing damage throughout the block. IPM-CPR significantly reduces the area managed by growers for control of H. halys, while simultaneously managing key pests at levels equal to current grower standard practices. This approach brings IPM tactics back into the orchard system after disruption by the invasive H. halys and potentially supports beneficial insects.

Transcriptome-Based Identification of ABC Transporters in the Western Tarnished Plant Bug Lygus hesperus

ATP-binding cassette (ABC) transporters are a large superfamily of proteins that mediate diverse physiological functions by coupling ATP hydrolysis with substrate transport across lipid membranes. In insects, these proteins play roles in metabolism, development, eye pigmentation, and xenobiotic clearance. While ABC transporters have been extensively studied in vertebrates, less is known concerning this superfamily in insects, particularly hemipteran pests. We used RNA-Seq transcriptome sequencing to identify 65 putative ABC transporter sequences (including 36 full-length sequences) from the eight ABC subfamilies in the western tarnished plant bug (Lygus hesperus), a polyphagous agricultural pest. Phylogenetic analyses revealed clear orthologous relationships with ABC transporters linked to insecticide/xenobiotic clearance and indicated lineage specific expansion of the L. hesperus ABCG and ABCH subfamilies. The transcriptional profile of 13 LhABCs representative of the ABCA, ABCB, ABCC, ABCG, and ABCH subfamilies was examined across L. hesperus development and within sex-specific adult tissues. All of the transcripts were amplified from both reproductively immature and mature adults and all but LhABCA8 were expressed to some degree in eggs. Expression of LhABCA8 was spatially localized to the testis and temporally timed with male reproductive development, suggesting a potential role in sexual maturation and/or spermatozoa protection. Elevated expression of LhABCC5 in Malpighian tubules suggests a possible role in xenobiotic clearance. Our results provide the first transcriptome-wide analysis of ABC transporters in an agriculturally important hemipteran pest and, because ABC transporters are known to be important mediators of insecticidal resistance, will provide the basis for future biochemical and toxicological studies on the role of this protein family in insecticide resistance in Lygus species.

Registration of Arkot 0305, Arkot 0306, Arkot 0309, and Arkot 0316 Germplasm Lines of Cotton

Arkansas Agricultural Experiment Station has released four germplasm lines of Upland cotton, Gossypium hirsutum L., designated as Arkot 0305 (Reg. No. GP-983, PI 669971), Arkot 0306 (Reg. No. GP-984, PI 671966), Arkot 0309 (Reg. No. GP-981, PI 669969), and Arkot 0316 (Reg. No. GP-982, PI 669970). Arkot 0305, Arkot 0306, and Arkot 0316 were derived from crosses with one common parent, Arkot 9203-17. The second parent for Arkot 0305, Arkot 0306, and Arkot 0316 was ‘DP 491’, DPX99X35, and Arkot 9111, respectively. Arkot 0309 was derived from a cross of DP 491 and ‘FM 966’. All four lines exhibited high fiber density and produced equal or higher lint yields than ‘DP 393’ over 4 yr and four test sites in Arkansas. Arkot 0305, Arkot 0306, and Arkot 0316 produced higher yields than Arkot 0309. Basic yield components (lint index and seed per area) of Arkot 0305, Arkot 0309, and Arkot 0316 were similar to DP 393, while Arkot 0306 produced yield with lower lint index and higher seed per area. The lines differed with respect to lint fraction, plant height, maturity, and relative trichome density on leaves, stems, and bracts. All four lines displayed resistance to bacterial blight [caused by Xanthomonas axonopodis pv. malacearum (Smith) Dye] and Fusarium wilt [caused by Fusarium oxysporum Schlect. F. sp. vasinfectum (Atk.) Snyd. & Hans.]. Arkot 0305 and Arkot 0306 displayed resistance to tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), equal to DP 393, but higher than Arkot 0309 and Arkot 0316. Fiber quality of Arkot 0309 was superior to the other three Arkot lines and DP 393. Each line displayed high yielding ability, favorable yield components, specific host plant resistance traits, early maturity and acceptable-to-superior fiber quality.

Influence of Maize and Pigweed on Tarnished Plant Bug (Hemiptera: Miridae) Populations Infesting Cotton

Abstract. The influence of maize, Zea mays L., and pigweed, Amaranthus spp., on the abundance of tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), adults infesting cotton, Gossypium hirsutum L., in the Mississippi Delta was studied using stable-isotope analyses. Cotton fields adjacent to maize and those farther than 1.6 km from maize were identified in four counties of the Mississippi Delta. Tarnished plant bug adults were collected from the cotton fields weekly throughout the growing season and analyzed with stable-carbon and nitrogen isotopes to determine the natal host. The proportion of tarnished plant bug adults collected from cotton that developed as nymphs on plants that used the C4 photosynthetic pathway, primarily maize and pigweed, peaked from 79–92% during 2008–2009. Distance of cotton fields from maize did not influence the peak proportion of tarnished plant bug adults with a C4 signature from cotton fields, the peak time, or peak duration. Time of the C4 peaks occurred from 28 June...

PLANT PROTECTION CHALLENGES IN STRAWBERRY PRODUCTION IN NORTHERN EUROPE

Strawberry is cultivated in north Europe, also in the higher latitudes and it is the most important soft fruit crop in Finland. The cool climate has limited the spread of many strawberry pests to Finland, but this is now changing. Benefiting from the warming climate, strawberry tarsonemid mite (Tarsonemus pallidus) continues to be the most important pest. Biological control by use of predatory mites is widely adopted by growers. Two-spotted spider mite (Tetranychus urticae) is favoured by use of fibre cloth used to protect plants during winter and spring. Strawberry blossom weevil (Anthonomus rubi) and European tarnished plant bug (Lygus rugulipennis) are among the key pests, and in northern Finland strawberry leaf beetles (Galerucella spp.) can cause severe damage. Monitoring methods have been developed for these pests. Warming climate has increased thrips damage on fruits, and favours also the black vine weevil (Otiorhynchus sulcatus). Grey mould (Botrytis cinerea) is the main disease, and controlled with fungicides. Recently, also biological control has become more popular. Crown rot (Phytophthora cactorum) has spread to production fields. However, anthracnose (Colletotrichum acutatum) has not established itself in production fields. Leaf diseases (Mycosphaerella fragariae, Diplocarpon earlianum and Gnomonia comari) are quite common and powdery mildew (Podosphaera aphanis) has not been an important disease in open field. The main vector of strawberry viruses, strawberry aphid (Chaetosiphon fragaefolii), occurs not yet in Finland. In the future, mites are expected to be more harmful and also thrips and black vine weevil are favoured by warmer conditions. Considering diseases, Phytophthora species can be expected to increase in Finnish strawberry fields.

A Biological Comparison of Tarnished Plant Bug (Hemiptera: Miridae) Populations From Mississippi's Major Agricultural Regions

A laboratory experiment was performed to compare fitness parameters of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), populations collected from the Hills and Delta regions of Mississippi. Each population was split into two cohorts to be reared on cotton or artificial diet to make comparisons of food source and region of collection. Each population was maintained separately and allowed to mate. Nymphal survivorship from the F1 generation of each population from each region and food source was compared. Parameters measured included development times to fourth instar, fifth instar and adult, total nymphal survivorship, fecundity, and fertility. Populations collected from the Delta region and reared on cotton developed significantly faster at all life stages than other populations. Tarnished plant bugs from the Hills reared on cotton developed significantly slower than other populations, except those from the Hills reared on artificial diet. Populations reared on diet had significantly higher survivorship than those reared on cotton. Tarnished plant bug populations from the Delta region laid significantly more eggs per female per day than those from the Hills region. Populations reared on cotton also laid significantly more eggs per female per day than those reared on diet. Populations collected in the Delta region laid significantly more viable eggs per female per day than those from the Hills region. Tarnished plant bugs reared on cotton produced significantly more nymphs per female per day than those reared on diet. These data indicate there are differences in several fitness parameters between tarnished plant bug populations from the Hills and Delta regions of Mississippi.

Altered gene regulation and potential association with metabolic resistance development to imidacloprid in the tarnished plant bug,Lygus lineolaris

Chemical spray on cotton is almost an exclusive method for controlling tarnished plant bug (TPB), Lygus lineolaris. Frequent use of imidacloprid is a concern for neonicotinoid resistance in this key pest. Information of how and why TPB becomes less susceptible to imidacloprid is essential for effective monitoring and managing resistance. Microarray analysis of 6688 genes in imidacloprid-selected TPB (Im1500FF) revealed 955 upregulated and 1277 downregulated (≥twofold) genes in Im1500FF, with 369 and 485 of them annotated. Five P450 and nine esterase genes were significantly upregulated, and only one esterase gene and no P450 genes were downregulated. Other upregulated genes include helicases, phosphodiesterases, ATPases and kinases. Pathway analyses identified 65 upregulated cDNAs that encode 51 different enzymes involved in 62 different pathways, including P450 and esterase genes for drug and xenobiotic metabolisms. Sixty-four downregulated cDNAs code only 17 enzymes that are associated with only 23 pathways mostly related to food digestion. This study demonstrated a significant change in gene expression related to metabolic processes in imidacloprid-selected TPB, resulting in overexpression of P450 and esterase genes for potential excess detoxification and cross/multiple resistance development. The identification of these and other enzyme genes establishes a foundation to explore the complicity of potential imidacloprid resistance in TPB.

Effects of Field Plot Size on Variation in White Flower Anther Injury by Tarnished Plant Bug for Host Plant Resistance Evaluations in Arkansas Cotton

Field trials conducted in 2008 and 2009 investigated whether plot size affects incidence of white flower anther injury by tarnished plant bug (Lygus lineolaris (Palisot de Beauvois)) in host plant resistance (HPR) evaluations. The three cotton lines evaluated in the trial included a susceptible frego bract line (RBCDHGPIQH-197) and 2 standards, SureGrow (SG) 105 and Deltapine (DP) 393. Samplers monitored white flower anther injury between single row mini-plots embedded within multiple row max-plots. A sub-section of the max-plots was sprayed with insecticides to evaluate these tactics on altering the incidence of white flower anther injury. Plant bug numbers were very low in 2008, while infestation levels were higher in 2009. Significantly higher numbers of flowers with anther injury were observed in both years in the susceptible frego bract line compared to SG 105 and DP 393 lines. In both years, anther injury levels were similar in the max- and mini-plots, with lower levels observed in max-sprayed plots. The white flower monitoring procedure is a consistent indicator of adult plant bug preferences and is not influenced by plot size or interspersions of cultivar lines among plots.

Percussion signals of Lygus rugulipennis Poppius (Heteroptera: Miridae)

Abstract The European tarnished plant bug (Lygus rugulipennis Poppius) is among the most serious pests in the family Miridae, and therefore there is increasing interest in understanding the behaviour of this species. In the present study, laboratory recordings were taken using a laser vibrometer on adult males and females to ascertain whether acoustic signals are involved in intraspecific communication. Recordings were both carried out on plant and loudspeaker membrane substrates. Males and females emitted vibratory signals and the present results indicate that these signals are important during courtship. The basic signal characteristics measured were the dominant frequency, pulse duration, repetition time and number of pulses per group within the signal. Male and female signals did not differ in respect to any of these characteristics. Plant recorded signals were longer because of different mechanical properties of substrates. Additionally, the high frequency components were attenuated due to the low-pass filtering properties of plants. As this is the first study on vibratory communication of the European tarnished plant bug, we believe these findings may contribute considerably to the better understanding of the mating behavior of this important pest species.

Development and validation of a model forecasting the phenology of European tarnished plant bug Lygus rugulipennis in the U.K

Abstract The European tarnished plant bug Lygus rugulipennis has caused significant economic damage to strawberry production in the U.K. in recent years. Laboratory experiments were conducted to study L. rugulipennis development under fluctuating low temperatures. The results indicated that L. rugulipennis can develop at an appreciable rate at 10 °C. We have developed a model predicting the phenology of L. rugulipennis in the U.K. The model assumes that adults overwinter and uses temperature from the first day of a calendar year to simulate pest development. The model was validated against field observations of L. rugulipennis population dynamics monitored under both open‐field and protected conditions on weeds and strawberry plants. Predicted L. rugulipennis population patterns from the model agreed well with the observed data. The L. rugulipennis model can be used in practice to enable growers to identify the timing of the first generation of L. rugulipennis adult dispersal into strawberry, or other crops, from weeds. The model will also assist growers with the timing of the deployment of pheromone traps and interpreting the importance of trap catches. This will allow growers to better time and target applications of insecticides against damaging life stages of the pest.

Effect of Selected Insecticides onLygus hesperus(Heteroptera: Miridae) Oviposition Behavior in Cotton

Oviposition behavior of western tarnished plant bug, Lygus hesperus Knight, as affected by residual insecticides, was studied in potted as well as field-grown cotton. In this study, we investigated the spatial distribution and phytotomical preference of Lygus oviposition in presquaring and blooming cotton, as affected by selected insecticides. Flonicamid, acephate, and cypermethrin were applied to cotton at 82, 516, and 114 g (active ingredient)/ha, respectively. At 3 d posttreatment, a gravid female Lygus was caged on the plants. After 4 d, caged plants were harvested and eggs were counted by whole plant dissection. Results indicated significantly greater egg deposition in untreated controls than treated plants in both potted and field-grown cotton. For untreated plants, Lygus preferred to oviposit on the pulvinus and leaf petiole, where 76 and 85% of eggs were laid in potted and field-grown cotton, respectively. For insecticide-treated plants, no plant structure preference was observed, although fewer eggs were laid. The upper stratum of the plant canopy had significantly more eggs than the lower or middle strata of untreated plants, while more eggs were observed in the middle strata of plants treated with acephate in field-grown cotton. Sublethal effects could not be adequately assessed in the cypermethrin treatment owing to high Lygus mortality.

Identification and characterization of a sex peptide receptor‐like transcript from the western tarnished plant bug Lygus hesperus

Lygus hesperus females exhibit a post-mating behavioural switch that triggers increased egg laying and decreased sexual interest. In Drosophila melanogaster, these changes are controlled by sex peptide (SP) and the sex peptide receptor (DmSPR). In Helicoverpa armigera, SPR (HaSPR) also regulates some post-mating behaviour; however, myoinhibiting peptides (MIPs) have been identified as the SPR ancestral ligand, indicating that SPR is a pleiotropic receptor. In the present study, we identified a transcript, designated L. hesperus SPR (LhSPR), that is homologous to known SPRs and which is expressed throughout development and in most adult tissues. LhSPR was most abundant in female seminal depositories and heads as well as the hindgut/midgut of both sexes. In vitro analyses revealed that fluorescent chimeras of LhSPR, DmSPR and HaSPR localized to the cell surface of cultured insect cells, but only DmSPR and HaSPR bound carboxytetramethylrhodamine-labelled analogues of DmSP21-36 and DmMIP4. Injected DmSP21-36 also failed to have an effect on L. hesperus mating receptivity. Potential divergence in the LhSPR binding pocket may be linked to receptor-ligand co-evolution as 9 of 13 MIPs encoded by a putative L. hesperus MIP precursor exhibit an atypical W-X7 -Wamide motif vs the W-X6 -Wamide and W-X8 -Wamide motifs of Drosophila MIPs and SP.

The complete mitochondrial genome of the tarnished plant bug, Lygus lineolaris (Heteroptera: Miridae)

The complete mitochondrial genome of the tarnished plant bug, Lygus lineolaris, comprised 17,027 bp. The genome contained 13 protein coding regions, 22 tRNA genes and 2 ribosomal RNA genes. The gene arrangement corresponded to the common order found among insect mtDNAs which was considered to be the ancestral arrangement. The protein coding genes started with ATN and stopped with TAA or TAG. The nucleotide distribution was 76.0% A + T. The control region contained two repeat regions, one was 24 bp and the other was 161 bp. The Genbank accession for the complete L. lineolaris mt genome is EU401991.

Registration of Arkot 0111, Arkot 0113, and Arkot 0114 Germplasm Lines of Cotton

Arkot 0111 (Reg. No. GP-974, PI 664925), Arkot 0113 (Reg. No. GP-975, PI 664926), and Arkot 0114 (Reg. No. GP-976, PI 664927) are noncommercial breeding lines of cotton (Gossypium hirsutum L.) that were released by the Arkansas Agricultural Experiment Station in December 2011. The three lines were derived from crosses to a common parent, Arkot 9111. The second parent for Arkot 0111, Arkot 0113, and Arkot 0114 was ‘FM 958’, Arkot 9101, and Arkot 9108, respectively. All three lines were evaluated in replicated tests at four Arkansas sites from 2007 through 2010. Compared with ‘DP 393’, Arkot 0111 produced lower lint yields but had enhanced fiber quality; Arkot 0113 and Arkot 0114 produced higher lint yields and had similar fiber quality. Each line possessed favorable yield components. Maturity of the lines was similar to DP 393. Trichome density associated with leaves, stems, and bracts for Arkot 0111 and Arkot 0113 was greater than DP 393. Compared with DP 393, Arkot 0114 had higher leaf trichome density but lower trichome density on stems and bracts. All three lines expressed resistance to bacterial blight. All three lines were equal to SG 105 in response to tarnished plant bug, but Arkot 0111 and Arkot 0114 were more sensitive than Arkot 0113 or DP 393. The relative yield and line-specific host plant resistance traits make these lines valuable to cotton breeding programs.

Registration of Arkot 0219 and Arkot 0222 Germplasm Lines of Cotton

Arkansas Agricultural Experiment Station has released two germplasm lines of Upland cotton, Gossypium hirsutum L., designated as Arkot 0219 (Reg. No. GP-972, PI 668533) and Arkot 0222 (Reg. No. GP-973, PI 668534). Both lines were derived from crosses with one common parent, Arkot 9111. The second parent for Arkot 0219 and Arkot 0222 was the advanced breeding lines DES 810 and STX8M007, respectively. Arkot 0222 is a sister line to ‘UA222’. Both Arkot 0219 and Arkot 0222 produced higher yields than ‘DP 393’ and ‘SG 105’ at each of four test sites in Arkansas. Their high yields were achieved by a favorable combination of basic yield components, which should provide high yield stability. Both lines displayed high resistance to bacterial blight and were similar to DP 393 in their response to other diseases. Arkot 0222 displayed resistance to tarnished plant bug equal to DP 393 and UA222 but higher than SG 105 or Arkot 0219. Fiber quality of Arkot 0219 is similar to SG 105 but inferior to DP 393 and UA222. Fiber quality of Arkot 0222 is similar to DP 393 but inferior to UA222. Both lines display high yielding ability, favorable yield components, specific host plant resistance traits, early maturity, and acceptable fiber quality.

Molecular and functional characterization of multiple aquaporin water channel proteins from the western tarnished plant bug, Lygus hesperus

Aquaporins (AQPs) are integral membrane channel proteins that facilitate the bidirectional transfer of water or other small solutes across biological membranes involved in numerous essential physiological processes. In arthropods, AQPs belong to several subfamilies, which contribute to osmoregulation, respiration, cryoprotection, anhydrobiosis, and excretion. We cloned and characterized five novel AQPs from the western tarnished plant bug, Lygus hesperus, a polyphagous insect pest of food and fiber crops throughout western North America. The L. hesperus AQPs (LhAQP1-5) belong to different phylogenetic subfamilies, have unique transcription profiles and cellular localizations, and all transport water (but not glycerol) when heterologously expressed in Xenopus laevis oocytes. Our results demonstrate that multiple AQPs with possible compensatory functions are produced in L. hesperus that likely play important roles in maintaining water homeostasis in this important insect pest.

Impact of Planting Date and Varietal Maturity on Tarnished Plant Bug (Hemiptera: Miridae) in Cotton

A field experiment was conducted in Stoneville, MS, during 2010 and 2011 to investigate the impact of varietal maturity, planting date, and insecticide application on tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), populations and damage in cotton. Four planting dates were selected to encompass the cotton-planting period in Mississippi. An early and late maturing variety were planted at each planting date, and each variety and planting date combination was either sprayed or unsprayed for tarnished plant bugs. Plots were sampled weekly from first square until physiological maturity. Plots were harvested at the end of the season. Early planting dates had lower densities of tarnished plant bug and required fewer insecticide applications than the later planting dates. Mid-April to early May planting dates sustained less yield loss from tarnished plant bug than mid-May to late-May planting dates. Tarnished plant bug had less impact on yield of the early maturing variety than on the late maturing variety. The sprayed plots yielded more than unsprayed plots. These data demonstrate that later plantings of cotton in the Mississippi Delta are likely to experience yield losses from tarnished plant bug and need to be sprayed more compared with early cotton plantings. As a result, growers should manage their crop for earliness through planting date and varietal selection.