Profile of cotton fleahopper (Hemiptera: Miridae), an economic insect pest of cotton in Texas

Cotton fleahopper [Pseudatomoscelis seriatus (Reuter)] (Hemiptera: Miridae) is one of the most damaging insect pests of cotton (Gossypium hirsutum L.) in Texas and Oklahoma because of their feeding on small floral buds which are termed squares. Damage to early season squares can reduce yield, delay crop maturity and increase the risk of crop loss because of late season insect pests and adverse weather. Insecticide applications are the only control tactic. The objectives of this study were to determine the tolerance to cotton fleahopper injury to squares among upland cotton genotypes representing the adapted germplasm pools and breeding lines available to cotton breeders in the United States and to evaluate leaf hairiness as a resistant trait. Results of the choice and no-choice trials indicated that four entries, 'Stoneville 474', 'Suregrow 747', 'Deltapine 50', and 'TAM 96WD-22 h', were more tolerant to cotton fleahopper injury relative to the other 11 entries. In choice trials, cotton fleahopper density was significantly correlated with the density of trichomes on leaves, bracts and stems. However, there was no correlation between cotton fleahopper density and percent square damage in the choice trials, suggesting that in some genotypes the response to feeding injury is mediated by host plant resistance factors expressed as tolerance. Results of the no-choice studies also indicate that some genotypes express tolerance to cotton fleahopper feeding.

The cotton fleahopper, Pseudatomoscelis seriatus Reuter, is a widespread and important insect pest of cotton in Texas and Oklahoma. This plant bug feeds on small floral buds, which results in bud abscission, delayed fruiting, and subsequent crop loss. In central and southeastern Texas, two to four insecticide applications are typically applied for cotton fleahopper management. Primitive race stocks of cotton have been identified as an important source of resistance to a wide range of insect pests, but they have not been evaluated for resistance to cotton fleahopper. The objective of this study was to evaluate selected groups of primitive race stocks of Gossypium hirsutum L. for resistance to cotton fleahopper. Resistance was identified by caging cotton fleahoppers on cotton plants in a no-choice feeding trial and comparing the mean number of damaged squares per plant to a standard susceptible genotype. Four primitive race stocks, TX706, TX188, TX1530, and TX1156, were identified as resistant to cotton fleahopper in a collection of 65 primitive race stocks representing 18 genetic groups and collected throughout Mexico and Central America. No resistance was found in a collection of 11 accessions previously identified as resistant to Lygus spp. and no resistance was identified in a collection of 78 primitive accessions converted to day-neutrality. The possibility that some genetic resistance in these race stocks to the cotton fleahopper might have been lost as a result of the conversion to day-neutrality is discussed.

Several phytophagous insects exhibit distinct preference for their host plants. In widely distributed generalist insects, host preference can be influenced by geographic variation in host plant distribution and abundance as well as by prior experience. We have studied host preference of the cotton fleahopper, Pseudatomoscelis seriatus (Reuter), a pest of cotton in Texas and other neighboring states, by measuring olfactory orientation to horsemint (Monarda punctata L.) and cotton (Gossypium hirsutum L.). Horsemint is one of the primary, native, wild hosts of cotton fleahopper during late-spring and early summer in Texas, and it is commonly believed to be the main source of this pest in cotton. Although the abundance of horsemint, and therefore the fleahopper exposure to it, varies geographically, cotton fleahopper's preference for this native host-plant is maintained across two ecoregions in Texas, TX High Plains (Lubbock area) and Brazos Valley (College Station area). Similarly, preference for horsemint was retained regardless of prior experience with cotton throughout all the life stages of the insect. This fixed preference of cotton fleahopper to horsemint could be because of their ancestral insect-plant interaction, better fitness of cotton fleahopper on horsemint, and relatively low abundance of horsemint compared with cotton. Information gained from this study could be used to implement cultural control practices such as trap cropping, to develop attractants to monitor this pest, or both.

The cotton fleahopper (Pseudatomoscelis seriatus Reuter) is considered a highly economically damaging pest of cotton (Gossypium hirsutum L.) in Texas and Oklahoma. Current control methods rely heavily on the use of foliar-applied chemical insecticides, but considering the cost of insecticides and the critical timeliness of applications, chemical control methods are often not optimized to reduce potential yield losses from this pest. The Bacillus thuringiensis (Bt) Mpp51Aa2 (formerly Cry51Aa2.834_16) protein has proven effective against thrips and plant bugs with piercing and sucking feeding behaviors, but the impact of this toxin on cotton fleahoppers has not been investigated. To evaluate the Mpp51Aa2 trait effectiveness towards the cotton fleahopper, field trials were conducted in 2019, 2020, and 2021, comparing a cotton cultivar containing the Mpp51Aa2 trait to a non-traited isoline cultivar under insecticide-treated and untreated conditions. Populations of cotton fleahopper nymphs and adults were estimated weekly by visually inspecting cotton terminals. Square retention was also assessed during the first week of bloom to provide some insight on how the Bt trait may influence yield. While cotton fleahopper population differences between the traited and non-traited plants were not consistently noted during the pre-bloom squaring period, there was a consistent increase in square retention in cotton expressing Mpp51Aa2 relative to non-traited cotton. Additionally, cotton expressing Mpp51Aa2 offered similar square protection relative to non-traited cotton treated with insecticides for the cotton fleahopper. These findings indicate that the Mpp51Aa2 protein should provide benefits of delayed nymphal growth, population suppression, and increased square retention.

In Texas, the cotton fleahopper (Pseudatomoscelis seriatus (Reuter)) is considered a highly economically damaging pest of cotton (Gossypium hirsutum L.). Current control methods rely heavily on foliar chemical insecticides throughout the growing season. Considering the cost of insecticides and the critical timeliness of their application, chemical control methods are often not optimized to reduce potential yield losses. The Mpp51Aa2.834_16 gene in cotton (ThryvOn) has shown effectiveness against thrips and several piercing and sucking mirid insect pests, suggesting it has the potential to mitigate yield losses caused by the cotton fleahopper. Choice and no-choice caged feeding assays were conducted to assess the impact of cotton fleahoppers on ThryvOn cotton square retention under controlled laboratory conditions. In the choice assay, feeding by cotton fleahoppers significantly reduced square retention in the gene-lacking cotton to 46%, while the ThryvOn cotton retained 60% of the squares. In the no-choice assay, cotton fleahopper nymph feeding significantly reduced square retention in the cotton not expressing Mpp51Aa2 to 61%, whereas the ThryvOn cotton was unaffected. Based on the differences in square retention observed in both the choice and no-choice feeding assays, our findings indicate that the Mpp51Aa2 protein influences cotton fleahopper feeding preferences and the susceptibility of cotton plants to damage caused by cotton fleahoppers. Our study offers confirmation of the activity of ThryvOn on cotton fleahoppers observed in the field. The ThryvOn trait’s activity towards cotton fleahoppers is consistent with that found for other mirid pests in cotton.

Thrips (Thysanoptera: Thripidae( and cotton fleahoppers, Pseudatomoscelis seriatus (Reuter( (Hemiptera: Miridae(, are considered to be significant economic pests of cotton in Texas, USA. A 2-year field study evaluated the influence of planting date, tillage practice, and Bt cotton on seasonal abundance patterns of thrips and cotton fleahoppers and their within-plant distribution patterns in cotton. Thrips were sampled visually while fleahoppers were sampled both visually and with a ‘beat bucket’ at weekly intervals throughout the growing season. Thrips infestations had two distinct peaks, with the first peak at the one to two main stem node leaf stage and the second peak during the flowering stage. Cotton fleahoppers had only one infestation peak at 13 – 15 weeks after planting (after crop cutout(. Average seasonal abundance of each pest was significantly influenced by tillage practice with higher numbers in conventional tillage compared with that in conservation tillage plots. Thrips abundance was similar between the two cultivars, whereas cotton fleahopper abundance was significantly higher in non-Bt cotton compared with that in Bt cotton. Thrips average seasonal abundance was significantly higher in timely planted cotton compared with that in late-planted cotton. Thrips were more prevalent in upper one-third vertical stratum (51%( followed by middle stratum (33%( and the lower stratum (16%(. Cotton fleahopper within-plant distribution was similar to that for thrips, with 65, 24, and 11% of the total abundance found in upper, middle, and lower one-third of the plant, respectively.

Cotton fleahopper (Pseudatomoscelis seriatus Reuter) (Hemiptera: Miridae) is a piercing-sucking insect that has emerged as a major pest of cotton (Gossypium hirsutum L.) in Texas. Cotton fleahoppers feed on floral buds, commonly referred to as squares, causing damage and abscission, and subsequent yield loss. Previous studies indicate that plant resistance to cotton fleahopper is present in upland cotton, but the mechanism of resistance remains undetermined. In this study, Pilose, a cultigen of G. hirsutum, was examined as a source of resistance to cotton fleahopper, focusing on mechanism of resistance and heritability of the resistance trait. Results indicated that the resistance trait in Pilose is heritable and that pubescence is causative of resistance or that the resistance trait may be tightly linked to genes controlling pubescence. Behavioral assays indicated nonpreference as a mode of resistance in plants with dense pubescence.

A 2-yr field study was conducted to examine the effectiveness of two sampling methods (visual and plant washing techniques) for western flower thrips, Frankliniella occidentalis (Pergande), and five sampling methods (visual, beat bucket, drop cloth, sweep net, and vacuum) for cotton fleahopper, Pseudatomoscelis seriatus (Reuter), in Texas cotton, Gossypium hirsutum (L.), and to develop sequential sampling plans for each pest. The plant washing technique gave similar results to the visual method in detecting adult thrips, but the washing technique detected significantly higher number of thrips larvae compared with the visual sampling. Visual sampling detected the highest number of fleahoppers followed by beat bucket, drop cloth, vacuum, and sweep net sampling, with no significant difference in catch efficiency between vacuum and sweep net methods. However, based on fixed precision cost reliability, the sweep net sampling was the most cost-effective method followed by vacuum, beat bucket, drop cloth, and visual sampling. Taylor's Power Law analysis revealed that the field dispersion patterns of both thrips and fleahoppers were aggregated throughout the crop growing season. For thrips management decision based on visual sampling (0.25 precision), 15 plants were estimated to be the minimum sample size when the estimated population density was one thrips per plant, whereas the minimum sample size was nine plants when thrips density approached 10 thrips per plant. The minimum visual sample size for cotton fleahoppers was 16 plants when the density was one fleahopper per plant, but the sample size decreased rapidly with an increase in fleahopper density, requiring only four plants to be sampled when the density was 10 fleahoppers per plant. Sequential sampling plans were developed and validated with independent data for both thrips and cotton fleahoppers.

A 2-yr field study was conducted to examine the effectiveness of two sampling methods (visual and plant washing techniques) for western flower thrips, Frankliniella occidentalis (Pergande), and five sampling methods (visual, beat bucket, drop cloth, sweep net, and vacuum) for cotton fleahopper, Pseudatomoscelis seriatus (Reuter), in Texas cotton, Gossypium hirsutum (L.), and to develop sequential sampling plans for each pest. The plant washing technique gave similar results to the visual method in detecting adult thrips, but the washing technique detected significantly higher number of thrips larvae compared with the visual sampling. Visual sampling detected the highest number of fleahoppers followed by beat bucket, drop cloth, vacuum, and sweep net sampling, with no significant difference in catch efficiency between vacuum and sweep net methods. However, based on fixed precision cost reliability, the sweep net sampling was the most cost-effective method followed by vacuum, beat bucket, drop cloth, and visual sampling. Taylor’s Power Law analysis revealed that the field dispersion patterns of both thrips and fleahoppers were aggregated throughout the crop growing season. For thrips management decision based on visual sampling (0.25 precision), 15 plants were estimated to be the minimum sample size when the estimated population density was one thrips per plant, whereas the minimum sample size was nine plants when thrips density approached 10 thrips per plant. The minimum visual sample size for cotton fleahoppers was 16 plants when the density was one fleahopper per plant, but the sample size decreased rapidly with an increase in fleahopper density, requiring only four plants to be sampled when the density was 10 fleahoppers per plant. Sequential sampling plans were developed and validated with independent data for both thrips and cotton fleahoppers.

The cotton fleahopper, Pseudatomoscelis seriatus (Reuter), is an early-season pest of developing cotton in Central Texas and other regions of the Cotton Belt. Cotton fleahopper populations develop on spring weed hosts and move to cotton as weed hosts senesce or if other weed hosts are not readily available. To identify weed hosts that were seasonably available for the cotton fleahopper in Central Texas, blooming weed species were sampled during early-season (17 March-31 May), mid-season (1 June-14 August), late-season (15 August-30 November), and overwintering (1 December-16 March) periods. The leading hosts for cotton fleahopper adults and nymphs were evening primrose (Oenothera speciosa T. Nuttall) and Mexican hat [Ratibida columnifera (T. Nuttall) E. Wooton and P. Standley], respectively, during the early season. During the mid-season, silver-leaf nightshade (Solanum elaeagnifolium A. Cavanilles) was consistently a host for fleahopper nymphs and adults. Woolly croton (Croton capitatus A. Michaux) was a leading host during the late season. Cotton fleahoppers were not collected during the overwintering period. Other suitable hosts were available before previously reported leading hosts became available. Eight previously unreported weed species were documented as temporary hosts. A compendium of reported hosts, which includes >160 plant species representing 35 families, for the cotton fleahopper is provided for future research addressing insect-host plant associations. Leading plant families were Asteraceae, Lamiaceae, and Onagraceae. Results presented here indicate a strong argument for assessing weed species diversity and abundance for the control of the cotton fleahopper in the Cotton Belt.

The cotton fleahopper, Pseudatomoscelis seriatus (Reuter), is an economic pest of Texas cotton, Gossypium hirsutum L., that feeds on and causes abortion of early-stage squares. Cotton fleahopper eggs are laid in late fall and overwinter on woolly croton, Croton capitatus Michx. Cotton fleahoppers terminate diapause in early spring in response to minimum required temperature and moisture conditions. A laboratory study quantified the effects of different amounts of moisture (soaking durations of field-collected dead woolly croton plants) on the emergence of cotton fleahopper nymphs from diapaused eggs. Five moisture treatments evaluated were: 1) 24-hour initial soaking and no further moistening of the substrate for the remainder of emergence duration (T1); 2) 2-hour initial soaking followed by daily mist spraying of the substrate (T2); 3) 2-hour initial soaking followed by 30-minute soaking for the next 7 days and thereafter mist spraying daily (T3); 4) 2-hour initial soaking followed by 30-minute soaking for the next 7 days and thereafter dipping the substrate in water daily (T4); and 5) soaking for 15 minutes every other day (T5). Emergence of nymphs started 6 days after initial incubation in T3, while the latest emergence was recorded from T2. Peak nymphal emergence was recorded 12-days after incubation. Significantly more (P = 0.05) nymphs emerged from T4 (n = 425) and T3 (n = 404) than from T1 (n = 173), T2 (n = 290), or T5 (n = 293). To maximize fleahopper emergence from overwintered eggs in a laboratory, it was recommended that egg hatching be activated by soaking host substrate (croton) for 30 minutes daily for about 7 days and keeping the substrate moist throughout the emergence period.

Cotton fleahopper, Pseudatomoscelis seriatus Reuter (Hemiptera: Miridae), is an early season pest of upland cotton, Gossypium hirsutum L. Feeding damage from this pest causes square abscission. The response of commercial cotton cultivars with varying maturity traits to cotton fleahopper feeding was assessed. The hypothesis was that feeding affects early and late-maturing cultivars differently in maturity delays and yield. Field experiments with natural and artificial infestations were conducted in Corpus Christi, TX. For the natural infestation experiment, 4 cultivars (DP 2020 B3XF, DP 2012 B3XF, PHY 332 W3FE, and PHY 545 W3FE) were assigned to main plots, with subplots either sprayed or not sprayed with thiamethoxam insecticide to control cotton fleahopper early in the season. The artificial infestation experiment used 2 cultivars (DP 2020 B3XF and PHY 545 W3FE) as main plots, with subplots infested to or not infested with cotton fleahopper using single square caging. In the no-spray subplots of the natural infestation experiment, cotton fleahopper feeding increased square abscission, leading to yield loss and delayed boll maturity, especially in cultivars classified as late-maturing. Early maturing cultivars consistently showed faster boll opening regardless of cotton fleahopper. Artificial infestation experiments further confirmed increased square abscission, reduced boll numbers, and lower lint weights when infested with cotton fleahopper. Early maturing cultivars are more resilient and may be particularly useful in areas with high cotton fleahopper pressure, especially when scheduling an early harvest is desirable.

Insect herbivores may undergo genetic divergence on their host plants through host-associated differentiation (HAD). Much of what we know about HAD involves insect species with narrow host ranges (i.e., specialists) that spend part or all their life cycle inside their hosts, and/or reproduce asexually (e.g., parthenogenetic insects), all of which are thought to facilitate HAD. However, sexually reproducing polyphagous insects can also exhibit HAD. Few sexually reproducing insects have been tested for HAD, and when they have insects from only a handful of potential host-plant populations have been tested, making it difficult to predict how common HAD is when one considers the entire species’ host range. This question is particularly relevant when considering insect pests, as host-associated populations may differ in traits relevant to their control. Here, we tested for HAD in a cotton (Gossypium hirsutum) pest, the cotton fleahopper (CFH) (Pseudatomoscelis seriatus), a sexually reproducing, highly polyphagous hemipteran insect. A previous study detected one incidence of HAD among three of its host plants. We used Amplified fragment length polymorphism (AFLP) markers to assess HAD in CFH collected from an expanded array of 13 host-plant species belonging to seven families. Overall, four genetically distinct populations were found. One genetically distinct genotype was exclusively associated with one of the host-plant species while the other three were observed across more than one host-plant species. The relatively low degree of HAD in CFH compared to the pea aphid, another hemipteran insect, stresses the likely importance of sexual recombination as a factor increasing the likelihood of HAD.

The cotton fleahopper, Pseudatomocelis seriatus (Reuter), is a major pest of cotton, Gossypium hirsutum L., in Texas and Oklahoma. Although commonly studied as a cotton pest, little is known of the insect parasitoids attacking cotton fleahopper nymphs and adults. We surveyed parasitoids of cotton fleahopper collected during 2 years from wild plant hosts in 17 Texas counties from the Rio Grande Valley to northcentral Texas. The only parasitoid found was Leiophron uniformis (Gahan) (Braconidae). Parasitoids were recovered from 2–4% of nymphs and 0–1% of adults as determined by dissection or by holding cotton fleahoppers for parasitoid emergence. The parasitoid was reared from cotton fleahopper collected from Monarda spp., Solanum elaeagnifolium A. Cavanilles, and Croton glandulosus L., but was not recovered from cotton fleahopper collected on Croton capitatus A. Michaux or Tidestromia lanuginosa (Nutt.) Standl. The low parasitism rate suggested that importation and establishment of parasitoids might be beneficial if increased parasitism resulted in fewer cotton fleahopper adults dispersing from wild hosts into cotton.

BackgroundCotton fiber quality and seed composition play vital roles in the economics of cotton production systems and the cottonseed meal industry. This research aimed to examine the effects of different irrigation levels and planting geometries on fiber quality and seed composition of cotton (Gossypium hirsutum L.). We conducted a 2-year study in 2018 and 2019 in a warm, humid area in the Southeast United States on Dundee silt loam soil. There were three irrigation treatments in the study. The treatments included irrigating every furrow, or full irrigation (FI), every alternate furrow, or half irrigation (HI), and no irrigation, or rain-fed (RF). Planting geometries were on ridges spaced 102 cm apart and either a single-row (SR) or twin-rows (TR).ResultsThe results of high-volume instrument (HVI), advanced fiber information systems (AFIS) and near-infrared reflectance spectroscopy (NIRS) showed that irrigation and planting treatments played a significant role in fiber quality and seed composition. Across irrigation treatments, significant differences were seen in fiber properties, including fineness, maturity ratio, micronaire, neps, short fiber, strength, uniformity, upper half mean length (UHML), upper quartile length by weight (UQLw), and yellowness (+b). Irrigation and planting geometry (PG) had a significant effect on micronaire, strength, and UHML while their interaction was significant only for micronaire. The micronaire was negatively affected by irrigation as FI-SR, FI-TR, HI-SR, and HI-TR recorded 11% ~ 12% lower over the RF-SR and TR treatments. The PG played a minor role in determining fiber quality traits like micronaire and nep count. Irrigation treatments produced significantly lower (3% ~ 4%) protein content than rain-fed, while oil content increased significantly (6% ~ 10%).ConclusionsThe study results indicate a potential for improving cotton fiber and seed qualities by managing irrigation and planting geometries in cotton production systems in the Mississippi (MS) Delta region. The HI-TR system appears promising for lint and seed quality.