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Relevance. The study is aimed at evaluating the biological effectiveness of insecticides to reduce the number of tobacco thrips and gourd aphids in a film greenhouse on gourds. These pests cause significant damage to plants and can carry a viral infection. In greenhouse conditions, tobacco thrips can produce up to 7-8 generations, and melon aphid – up to 16 generations per season. The recommended pest control products have a limited protective duration in protected ground conditions, and in most cases promote the development of resistance in insects.Results. The article presents the results on the use of the insectoacaricide MatrinBio, BP against melon aphids and tobacco thrips, and the biological effectiveness in reducing the number of pests is determined. A single treatment with a bioinsecticide kills up to 90% of tobacco thrips insects. Efficiency against melon aphids is 27% lower. It is noted that the period of the protective action of MatrinBio, BP lasts up to seven days, then decreases. On the fourteenth day, the biological effectiveness against pests is; for thrips – 72%, and for aphids – 40%. For comparison, bioinsecticide Fitoverm, EC, was chosen as a standard, which showed worse results in reducing the number of tobacco thrips (less by 20...25%), but had the best protective effect against melon aphids - by 19...21%. Re-treatment with drugs seven days after the first one significantly reduced the number of pests. To prevent the emergence of resistance in pests in protected ground conditions, it is recommended to include MatrinBio, BP in the integrated protection system and alternate with insectoacaricides from other classes or use in various combinations.

[Objectives] The paper was to explore the influence of unmanned aerial vehicle (UAV) low volume spray technology on the control effect of viruliferous thrips and tomato spotted wilt virus (TSWV) under different pesticide concentrations, and to explore the effective control nodes and methods of thrips and TSWV. [Methods] According to the occurrence characteristics of thrips and TSWV, the field control effects of 4 pesticides on thrips and TSWV were tested by UAV with the thrips number and disease index as indicators, following the principle of regional and periodic control trials. [ Results] In the groups of UAV and artificial prevention and control, 4 agents were used alternatively, including 1% emamectin benzoate ME, 1.7% abamectin imidacloprid ME, 5% emamectin benzoate WDG, and 30% pyriproxyfen dinotefuran SL. There was no significant difference in the control effect of thrips and TSWV among treatment 1 (recommended dosage of UAV agent), treatment 2 (reduction of recommended dosage of UAV agent by 25%) and treatment4 (recommended dosage of artificial control agent), and the control effects on thrips were more than 83. 16% in the 3 treatments. The disease index of TSWV in the 3 treatments decreased from 8.64 ±1.37 in the blank control group to less than 3, which reached the prevention and control threshold. But treatment 3 (reduction of recommended dosage of UAV agent by 50%) did not reach the prevention and control threshold. The disease index of TSWV in the blank control area increased with the increase of the number of live nymphs of thrips, and there was a significant positive correlation, with good fitness. [ Conclusions] UAV has a significant impact on the control effect of thrips and TSWV under different pesticide concentrations. In the actual flight control application, it is recommended that the amount of the pesticides is about 3/4 and not less than 1/2 of that of the artificial application. The control area should be extended to 100 m of the ridge of the tobacco field, and UAV is used periodically to control thrips and TSWV for 5 times from pre-transplanting stage to pre-squaring stage of flue-cured tobacco. The control effect is significantly different from the traditional artificial application. [ABSTRACT FROM AUTHOR]

Simple Summary: Transgenic Bt crops are important tools for growers to manage insect pests, but their use is threatened by the evolution of insect resistance, and monitoring programs are essential in detecting and responding to resistance. For Bt products in which insect control is not complete ("non-high-dose crops"), resistance monitoring is challenging, because insects and insect damage will be present even without resistance. Given these challenges, "sentinel plots" (designated monitoring plots) consisting of Bt and non-Bt control plots have been used to monitor for insect resistance to non-high-dose Bt crops by assessing changes in the efficacy of a Bt crop over time relative to a non-Bt control. We used this approach for ThryvOn™ cotton, a new non-high-dose Bt product targeting two sucking pest types—Lygus and thrips—and report here on the thrips monitoring program. Monitoring for insect resistance over time requires knowledge of the baseline susceptibility, which is the initial assessment of the insect population response to a given Bt crop prior to its widespread adoption. To characterize the baseline susceptibility of thrips to ThryvOn, we tested several approaches and found that the number of immature thrips on ThryvOn relative to the control cotton best characterized the efficacy of the trait. Transgenic Bt crops are important tools for growers to manage insect pests, but their durability is threatened by the evolution of insect resistance. Implementing a resistance monitoring program is essential to detect and mitigate resistance. For non-high-dose Bt crops, resistance monitoring is challenging, because insect control is not complete, so targeted insects and insect damage will be present even without resistance. Given these challenges, sentinel plots have been used to monitor for insect resistance to non-high-dose crops by assessing changes in the efficacy of a Bt crop over time relative to a non-Bt control. We optimized a sentinel plot resistance monitoring approach for MON 88702 ThryvOn™ cotton, a new non-high-dose Bt product targeting two sucking pest taxa—Lygus (L. lineolaris and L. hesperus) and thrips (Frankliniella fusca and F. occidentalis)—and report here on the thrips monitoring methods and results. Quantifying thrips immatures was the best metric to characterize the impact of the trait, with at least a 40–60% average reduction of thrips immatures on ThryvOn relative to the control cotton at all sites with higher thrips densities. These data can be used within a ThryvOn resistance monitoring program and represent a case study for establishing a resistance monitoring approach for a non-high-dose trait product. [ABSTRACT FROM AUTHOR]

Transgenic Bt crops are important tools for growers to manage insect pests, but their durability is threatened by the evolution of insect resistance. Implementing a resistance monitoring program is essential to detect and mitigate resistance. For non-high-dose Bt crops, resistance monitoring is challenging, because insect control is not complete, so targeted insects and insect damage will be present even without resistance. Given these challenges, sentinel plots have been used to monitor for insect resistance to non-high-dose crops by assessing changes in the efficacy of a Bt crop over time relative to a non-Bt control. We optimized a sentinel plot resistance monitoring approach for MON 88702 ThryvOn™ cotton, a new non-high-dose Bt product targeting two sucking pest taxa—Lygus (L. lineolaris and L. hesperus) and thrips (Frankliniella fusca and F. occidentalis)—and report here on the thrips monitoring methods and results. Quantifying thrips immatures was the best metric to characterize the impact of the trait, with at least a 40–60% average reduction of thrips immatures on ThryvOn relative to the control cotton at all sites with higher thrips densities. These data can be used within a ThryvOn resistance monitoring program and represent a case study for establishing a resistance monitoring approach for a non-high-dose trait product.

Frankliniella fusca Hinds (Thysanoptera: Thripidae) is an economically important pest of many cultivated crops including cotton, tomatoes, peppers and tobacco. Previous research has focused on the importance of non‐crop weeds for F. fusca populations when estimating crop infestation risk in the spring. Although weeds play an integral role in population development, early‐season cultivated hosts (e.g. wheat and sage) may also contribute and augment overall populations. Few studies have examined the role of early‐season crops as a source habitat for sensitive host crops later in the season. The goal of this study was to investigate the abiotic conditions and landscape components that are associated with F. fusca populations in winter wheat (Triticum aestivum L.). Exploring these relationships will provide insight into early‐season drivers of F. fusca. To do this, we conducted a 2 year study documenting F. fusca populations during an 8 weeks period each spring. We sampled immature thrips abundance on wheat heads while concurrently monitoring adult dispersal from the field using yellow sticky cards. Across both years, we found that immature thrips sampled during the milk and dough development stages best‐predicted adult dispersal 2 weeks later. Cumulative precipitation and the number of precipitation events beginning in the autumn of the prior year were the most important abiotic predictors of F. fusca abundance. At the landscape scale, adult F. fusca density was negatively related to the area of row crop agriculture, grasslands and amount of landscape fragmentation. Results of our study provide a basis to assess larval thrips and forecast dispersal of this pest from wheat using a head sampling method. At a landscape scale, we show that specific combinations of abiotic and landscape variables influence population abundance of F. fusca in North Carolina row crop agroecosystems. [ABSTRACT FROM AUTHOR]

The tobacco thrips, Frankliniella fusca Hinds, is a phytophagous pest and vector of orthotospoviruses in many crops around the world. F. fusca causes direct feeding injury to peanut plants, resulting in leaf chlorosis and curling, and yield loss. Adults and larvae also transmit the economically important tomato spotted wilt orthotospovirus (TSWV) in all peanut market types grown in the U.S. TSWV infection causes spotted wilt disease, a plant disease characterized by chlorosis, stunting, and death. From 1996 to 2006, spotted wilt disease resulted in an estimated U.S.$140 million in annual peanut production losses in the U.S. At present, a thorough documentation of F. fusca 's impacts on the U.S. peanut production system is not available. Here, we describe the morphology, life cycle, and biology of F. fusca and provide images of immature life stages. Feeding injury characteristics and TSWV transmission in peanuts are also discussed. Currently, F. fusca and TSWV are managed in peanut with a combination of tactics, including prophylactic insecticide applications and TSWV-resistant cultivars. However, standardized scouting protocols and economic thresholds for F. fusca are not yet available. Very few biological control agents have been evaluated for use against F. fusca , and few studies have quantified the contributions of native natural enemies. More research into natural enemies' contributions to F. fusca management and the mechanisms underlying TSWV-resistance in peanut could help inform and diversify integrated pest management programs. [ABSTRACT FROM AUTHOR]

Thrips (Thysanoptera) are the most prevalent early season pests of cotton and are often detrimental to the establishing crop. Heavy reliance on prophylactic insecticides, primarily used as seed treatments, has led to insecticide resistance in populations of Frankliniella fusca Hinds. Sustainable, alternative management tactics are needed to protect seedling cotton from thrips. We evaluated day-neutral, exotic landraces (N = 164) of Upland cotton (Gossypium hirsutum L.) for thrips-resistance traits in three field trials using insecticide-treated and -untreated plots. The cotton landraces were chosen for their diverse backgrounds, unique genotypes, and day-neutrality, allowing them to easily cross with USA breeding lines. The trials were conducted at the North Carolina State University Sandhills Research Station in Jackson Springs, NC (NC2018), and the Clemson University Pee Dee Research and Education Center in Florence, SC (SC2018 and SC2020). A selection index was created to quantify thrips resistance based on densities of thrips and ratings of injury by thrips at the first and third true-leaf stages in untreated plots, and genotypic differences in above-ground dry biomass between treated and untreated plots at 42 days after planting. Subsamples of adult thrips were collected for species identification. Dominant thrips species were F. fusca in NC2018 and SC2020 and Frankliniella tritici in SC2018. Eight putatively thrips-resistant genotypes (TX-1109, TX-1975, TX-2320, TX-2383, TX-101, TX-2347, TX-2362, TX-251) and four putatively thrips-susceptible genotypes (TX-203, TX-1212, TX-1094, TX-2403-2) were identified in the field trials. Further investigation of the putatively thrips-resistant and -susceptible genotypes should focus on mechanisms of thrips resistance to enhance future breeding efforts. • Thrips are key pests of cotton that are resistant to commonly used insecticides. • Host plant resistance has potential as an alternative control tactic. • Exotic cotton landraces were screened using multiple field trials. • A novel selection index was used to identify resistant and susceptible genotypes. [ABSTRACT FROM AUTHOR]