Influence of elevated CO2 on development and food utilization of armyworm Mythimna separata fed on transgenic Bt maize infected by nitrogen-fixing bacteria

Background Bt crops will face a new ecological risk of reduced effectiveness against target-insect pests owing to the general decrease in exogenous-toxin content in Bt crops grown under elevated carbon dioxide (CO2). The method chosen to deal with this issue may affect the sustainability of transgenic crops as an effective pest management tool, especially under future atmospheric CO2 level raising. Methods In this study, rhizobacterias, as being one potential biological regulator to enhance nitrogen utilization efficiency of crops, was selected and the effects of Bt maize (Line IE09S034 with Cry1Ie vs. its parental line of non-Bt maize Xianyu 335) infected by Azospirillum brasilense (AB) and Azotobacter chroococcum (AC) on the development and food utilization of the target Mythimna separate under ambient and double-ambient CO2 in open-top chambers from 2016 to 2017. Results The results indicated that rhizobacteria infection significantly increased the larval life-span, pupal duration, relative consumption rate and approximate digestibility of M. separata, and significantly decreased the pupation rate, pupal weight, adult longevity, fecundity, relative growth rate, efficiency of conversion of digested food and efficiency of conversion of ingested food of M. separata fed on Bt maize, while here were opposite trends in development and food utilization of M. separata fed on non-Bt maize infected with AB and AC compared with the control buffer in 2016 and 2017 regardless of CO2 level. Discussion Simultaneously, elevated CO2 and Bt maize both had negative influence on the development and food utilization of M. separata. Presumably, CO2 concentration arising in future significantly can increase their intake of food and harm to maize crop; however, Bt maize infected with rhizobacterias can reduce the field hazards from M. separata and the application of rhizobacteria infection can enhance the resistance of Bt maize against target lepidoptera pests especially under elevated CO2.

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Influence of elevated CO2 on development and food utilization of target armyworm Mythimna separata fed on transgenic Bt maize infected by nitrogen-fixing bacteria

10.1101/292565 ◽

2018 ◽

Author(s):

Zhuo Li ◽

Yingying Song ◽

Likun Li ◽

Long Wang ◽

Bin Liu ◽

...

Keyword(s):

Azospirillum Brasilense ◽

Insect Pests ◽

Azotobacter Chroococcum ◽

Utilization Efficiency ◽

Management Tool ◽

Food Utilization ◽

Mythimna Separata ◽

Bt Crops ◽

Mythimna Separate ◽

Buffer Control

AbstractBt crops will face a new ecological risk of reduced effectiveness against target-insect pests owing to the general decrease in exogenous-toxin content in Bt crops grown under elevated CO2. How to deal with this issue may affect the sustainability of transgenic crops as an effective pest management tool especially under future CO2 raising. In this study, azotobacters, as being one potential biological regulator to enhance crops’ nitrogen utilization efficiency, were selected and the effects of Bt maize and non-Bt maize infected by Azospirillum brasilense and Azotobacter chroococcum on development and food utilization of target Mythimna separate were studied under ambient and elevated CO2. The results indicated that azotobacter infection significantly increased larval life-span, pupal duration, RCR and AD of M. separata, and significantly decreased RGR, ECD and ECI of M. separata fed on Bt maize; There were opposite trends in development and food utilization of M. separata fed on non-Bt maize infected with azotobacters compared with the buffer control regardless of CO2 level. Presumably, the application of azotobacter infection could make Bt maize facing lower field hazards from the target pest of M. separate, and finally improve the resistance of Bt maize against target lepidoptera pests especially under elevated CO2.Summary statementElevated CO2 effect on development and food utilization of target armyworm Mythimna separata fed on Bt maize infected by azotobacter, Azospirillum brasilense and Azotobacter chroococcum

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Evaluation of Two Formulations of Chlorantraniliprole as Maize Protectants for the Management of Prostephanus truncatus (Horn) (Coleoptera: Bostrychidae)

Insects ◽

10.3390/insects12030194 ◽

2021 ◽

Vol 12 (3) ◽

pp. 194

Author(s):

Maria C. Boukouvala ◽

Nickolas G. Kavallieratos

Keyword(s):

Insect Pests ◽

Management Tool ◽

Prostephanus Truncatus ◽

Beneficial Arthropods ◽

Progeny Production ◽

Exposure Interval ◽

Low Toxicity ◽

Wood Boring ◽

Effective Compound ◽

Overall Mortality

The larger grain borer, Prostephanus truncatus (Horn) (Coleoptera: Bostrychidae) is one of the most destructive insect pests of stored maize and dried tubers of cassava, and a wood-boring species. In the present study, we examined two chlorantraniliprole formulations, WG (wettable granule) with 350 g/kg active ingredient (a.i.) and SC (suspension concentrate) with 200 g/L a.i., as maize protectants against P. truncatus adults. Chlorantraniliprole formulations were applied as solutions at 0.01, 0.1, 1 and 10 ppm, and tested at 20, 25 and 30 °C. Both formulations performed similarly. After 7 days of exposure, the overall mortality provided by both formulations was very low (<17%). Seven days later, mortality was remarkably increased on maize treated with 1 and 10 ppm at 25 and 30 °C for both formulations. The highest mortality was noted in chlorantraniliprole WG, at 10 ppm and 30 °C (98.9%), followed by chlorantraniliprole SC (96.1%), at the same dose and temperature. WG formulation was more effective at 10 ppm and 25 °C (92.8%) than SC formulation (89.4%). No progeny production was noted on maize treated with the WG formulation at 20 and 30 °C. The SC formulation caused complete offspring suppression at 10 ppm at all three tested temperatures. The results of the present work indicate that chlorantraniliprole is an effective compound with a high insecticidal activity against T. truncatus on stored maize that depends on temperature, dose and exposure interval. The fact that chlorantraniliprole is a broad-spectrum insecticide, exhibiting low toxicity to mammals and beneficial arthropods, could be a valuable management tool in storage facilities.

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Transgenerational Effects of a Neonicotinoid and a Novel Sulfoximine Insecticide on the Harlequin Ladybird

Insects ◽

10.3390/insects12080681 ◽

2021 ◽

Vol 12 (8) ◽

pp. 681

Author(s):

Changchun Dai ◽

Michele Ricupero ◽

Zequn Wang ◽

Nicolas Desneux ◽

Antonio Biondi ◽

...

Keyword(s):

Nicotinic Acetylcholine Receptors ◽

Harmonia Axyridis ◽

Biocontrol Agent ◽

Insect Pests ◽

Negative Influence ◽

Management Approach ◽

Generalist Predator ◽

Cotton Aphid ◽

Transgenerational Effects ◽

Harlequin Ladybird

The harlequin ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae), is a generalist predator and an effective biocontrol agent of various insect pests that has been exploited for the control of aphid pests in the greenhouse and field. However, insecticides are widely used to control aphid pests worldwide and the potential non-target effects of sulfoxaflor and imidacloprid for controlling aphid pests towards this biocontrol agent are little known. Although both sulfoxaflor and imidacloprid act on nicotinic acetylcholine receptors of insects, sulfoxaflor has a novel chemical structure compared with neonicotinoids. We assessed the lethal, sublethal and transgenerational effects of sulfoxaflor and imidacloprid on H. axyridis simultaneously exposed via ingestion of contaminated prey and via residual contact on the host plant at LC20 and LC50 doses estimated for the cotton aphid. Imidacloprid significantly reduced the survival of H. axyridis adults compared to sulfoxaflor at the same lethal concentration against cotton aphid. Both concentrations of imidacloprid and sulfoxaflor reduced the proportion of ovipositing females, and both concentrations of imidacloprid and sulfoxaflor, except LC20 dose of sulfoxaflor, reduced the fecundity and fertility of the parental generation. In the progeny of imidacloprid- and sulfoxaflor-exposed parents, both tested LC50 concentrations significantly decreased the juvenile survival rate, and both concentrations of imidacloprid and sulfoxaflor, except LC20 dose of sulfoxaflor, prolonged the development time. Our findings provide evidence of the negative influence of imidacloprid and sulfoxaflor at low lethal concentrations on the harlequin ladybird and on the progeny of exposed individuals, i.e., transgenerational effects. Hence, these findings stress the importance of optimizing the applications of imidacloprid and sulfoxaflor for the control of aphid pests, aiming at preserving the biocontrol services provided by H. axyridis throughout the integrated pest management approach.

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Methyl Benzoate Is Superior to Other Natural Fumigants for Controlling the Indian Meal Moth (Plodia interpunctella)

Insects ◽

10.3390/insects12010023 ◽

2020 ◽

Vol 12 (1) ◽

pp. 23

Author(s):

Md Munir Mostafiz ◽

Errol Hassan ◽

Rajendra Acharya ◽

Jae-Kyoung Shim ◽

Kyeong-Yeoll Lee

Keyword(s):

Insect Pests ◽

Insect Pest ◽

Plodia Interpunctella ◽

Methyl Benzoate ◽

Management Tool ◽

Contact Toxicity ◽

Fumigant Toxicity ◽

Indian Meal Moth ◽

Indian Meal ◽

Food Commodities

The Indian meal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), is an insect pest that commonly affects stored and postharvest agricultural products. For the control of insect pests and mites, methyl benzoate (MBe) is lethal as a fumigant and also causes contact toxicity; although it has already been established as a food-safe natural product, the fumigation toxicity of MBe has yet to be demonstrated in P. interpunctella. Herein, we evaluated MBe as a potential fumigant for controlling adults of P. interpunctella in two bioassays. Compared to the monoterpenes examined under laboratory conditions, MBe demonstrated high fumigant activity using a 1-L glass bottle at 1 μL/L air within 4 h of exposure. The median lethal concentration (LC50) of MBe was 0.1 μL/L air; the median lethal time (LT50) of MBe at 0.1, 0.3, 0.5, and 1 μL/L air was 3.8, 3.3, 2.8, and 2.0 h, respectively. Compared with commercially available monoterpene compounds used in pest control, MBe showed the highest fumigant toxicity (toxicity order as follows): MBe > citronellal > linalool > 1,8 cineole > limonene. Moreover, in a larger space assay, MBe caused 100% mortality of P. interpunctella at 0.01 μL/cm3 of air after 24 h of exposure. Therefore, MBe can be recommended for use in food security programs as an ecofriendly alternative fumigant. Specifically, it provides another management tool for curtailing the loss of stored food commodities due to P. interpunctella infestation.

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Dispersal and spatiotemporal distribution of Protapion fulvipes in white clover fields: implications for pest management

Journal of Pest Science ◽

10.1007/s10340-021-01408-w ◽

2021 ◽

Author(s):

Veronica Hederström ◽

Franklin N. Nyabuga ◽

Olle Anderbrant ◽

Glenn P. Svensson ◽

Maj Rundlöf ◽

...

Keyword(s):

Pest Management ◽

White Clover ◽

Insect Pests ◽

Animal Feed ◽

Main Tool ◽

Management Tool ◽

Pest Species ◽

Economic Injury Level ◽

Dispersal Capacity ◽

Clover Seed

AbstractYield loss caused by insect pests remains a substantial problem in agriculture. Chemical control, with potential negative effects on non-target organisms, is still the main tool for pest management. For pest species with limited dispersal capacity, rotation of the crop in time and space has potential as an alternative management measure. This is particularly important in organic farming, where most agrochemicals are prohibited, but also relevant as a complementary pest management strategy in conventional agriculture. Clover is an important crop used for animal feed and as green manure; however, seed-eating weevils can severely limit the seed yield. We hypothesized that the previous year’s clover seed fields constitute the major sources of weevil pests. Consequently, a greater distance to, and a smaller pest load from, this source should reduce the number of weevils colonizing the new seed fields. To map population dynamics and dispersal range of Protapion fulvipes, an economically important seed weevil specialized on white clover, we conducted field studies over four years in 45 white clover seed fields. We found that P. fulvipes overwinters close to its source field and disperses to new fields in early spring the following year. Pest abundance increased with pest load in the previous year’s seed field, but decreased by 68% per km distance to the previous year’s field. Thus, separation of seed production fields between years by 2–3 km would create a spatiotemporal pest management tool to reduce the pest infestation below the estimated economic injury level.

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THE EFFECT OF A MICROSPORIDIAN PARASITE ON THE DEVELOPMENT, REPRODUCTION, AND MORTALITY OF THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (CLEM.)

Canadian Journal of Zoology ◽

10.1139/z58-045 ◽

1958 ◽

Vol 36 (4) ◽

pp. 499-511 ◽

Cited By ~ 49

Author(s):

H. M. Thomson

Keyword(s):

Initial Dose ◽

Male Fertility ◽

Choristoneura Fumiferana ◽

Spruce Budworm ◽

Malpighian Tubules ◽

Pupal Weight ◽

Adult Longevity ◽

Microsporidian Parasite ◽

Pupal Development ◽

First Instar

Infection of the spruce budworm, Choristoneura fumiferana (Clem.), by the microsporidian parasite Perezia fumiferanae Thorn, retards both larval and pupal development and reduces pupal weight, fecundity, and adult longevity. These effects are more pronounced among the female insects. There is no evidence that the parasite affects male fertility, mate choice, or the fertility of eggs produced. The parasite causes some mortality, most of which occurs before the fifth instar. Among larvae infected orally, mortality seems to be related to the size of the initial dose. Mortality occurs equally in both sexes. The development and survival of the first instar and overwintering second instar are not affected by the parasite. It is suggested that the parasite causes most of the observed results by reducing the insect's ability to assimilate its food. Mortality, however, is believed to be due to the destruction of the mid-gut or Malpighian tubules.

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Gut Transcriptome Analysis Shows Different Food Utilization Efficiency by the Grasshopper Oedaleous asiaticus (Orthoptera: Acrididae)

Journal of Economic Entomology ◽

10.1093/jee/tox128 ◽

2017 ◽

Vol 110 (4) ◽

pp. 1831-1840 ◽

Cited By ~ 6

Author(s):

Xunbing Huang ◽

Mark Richard McNeill ◽

Jingchuan Ma ◽

Xinghu Qin ◽

Xiongbing Tu ◽

...

Keyword(s):

Transcriptome Analysis ◽

Utilization Efficiency ◽

Food Utilization

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Nutrient Expert for High Yield and Use Efficiency in Rainfed Bt Cotton Hybrids

Frontiers in Agronomy ◽

10.3389/fagro.2021.777300 ◽

2021 ◽

Vol 3 ◽

Author(s):

Angamuthu Manikandan ◽

Desouza Blaise ◽

Sudarshan Dutta ◽

T. Satyanarayana ◽

Bhargavi Bussa

Keyword(s):

Nutrient Uptake ◽

Crop Yields ◽

Insect Pests ◽

Nutrient Balance ◽

Central India ◽

The Other ◽

Utilization Efficiency ◽

High Yield ◽

Bt Cotton ◽

Fertilizer Recommendation

Low cotton productivity in the rainfed cotton grown in central India is attributed to abiotic (water and nutrients) and biotic (insect pests and diseases) stress. Nutrient stress can be overcome by providing nutrients in right amounts and at the right time when the plant needs the most. Field studies in cereal crops have demonstrated fertilizer recommendations by using the Nutrient Expert® (NE) decision support system to improve crop yields. However, such information in the case of the commercial crop, cotton, is scarce. Therefore, on-farm trials were conducted in three districts of Maharashtra, India during 2018–2020 with the hypothesis that the NE-based fertilizer recommendation would lead to higher cotton productivity and savings in fertilizer. Averaged over two seasons and locations, lint yield was significantly greater in the NE based than the recommended dose of fertilizer (RDF), soil test crop response (STCR), and farmers' practice (FP). Internal utilization efficiency (IE) did not differ among treatments for N (4.8 to 5.9 kg lint kg−1 nutrient uptake) and K (6.7 to 7.2 kg lint kg−1 nutrient uptake). With regard to the fertilizer P applied, the FP treatment had the least IE (17.0 kg lint kg−1 nutrient uptake) and was significantly lower than the other treatments. Partial nutrient balance (PNB) did not vary among treatments for applied fertilizer N. The FP treatment had PNB < 1 in case of fertilizer P and ~20 in the case of fertilizer K. This indicates farmers applied excess of P fertilizers. On the other hand, farmers in the region applied very small amount of K. Although the NE treatment had the highest cost of cultivation, net returns were the greatest followed by the STCR and RDF treatments. Our studies demonstrate that the NE-based fertilizer recommendation is not only productive, but also profitable.

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Keefektifan Nematoda Patogen Serangga Steinernema sp. Terhadap Achaea janata L., Serangga Pemakan Daun Jarak Kepyar (Ricinus communis)

Buletin Tanaman Tembakau Serat & Minyak Industri ◽

10.21082/bultas.v5n2.2013.58-68 ◽

2016 ◽

Vol 5 (2) ◽

pp. 58

Author(s):

Heri Prabowo ◽

I.G.A.A. Indrayani

Keyword(s):

Insect Pests ◽

Ricinus Communis ◽

Insect Pest ◽

Larval Mortality ◽

Infective Juvenile ◽

Pupal Weight ◽

Pathology Laboratory ◽

Randomized Design ◽

Achaea Janata ◽

Negative Impacts

Penggunaan pestisida kimia yang cukup tinggi pada akhir-akhir ini telah menimbulkan dampak negatif ter-hadap lingkungan, sehingga pengendalian hama yang ramah lingkungan sangat diperlukan. Saat ini, peng-gunaan nematoda entomopatogen terutama Steinernema sp., membuka peluang untuk digunakan sebagai pengendalian Achaea janata. Tujuan dari penelitian ini untuk mengetahui keefektifan Steinernema sp. ter-hadap A. Janata , dilaksanakan di laboratorium patologi serangga Balai Penelitan Tanaman Pemanis dan Serat pada bulan Maret sampai dengan Agustus 2011. Penelitian menggunakan rancanagan acak lengkap (RAL) dengan empat ulangan. Setiap ulangan menggunakan 25 larva A. janata instar 2. Larva diekspose de-ngan berbagai variasi konsentrasi Steinernema sp. dan kematian larva diamati setiap hari sampai 120 jam setelah infeksi. Konsentrasi Steinernema sp. yang digunakan adalah 0, 50, 100, 200, 300, dan 400 JI/larva. Hasil penelitian pemberian Steinernema sp. pada konsentrasi 200, 300, dan 400 JI/larva cukup efektif untuk membunuh A. janata dengan persentase berkisar antara 80–94% mulai 48–120 jam setelah perlakuan. Se-makin tinggi konsentrasi nematoda, semakin tinggi mortalitas A. janata. Steinernema sp. dengan konsen-trasi 400 JI/larva paling efektif membunuh larva, menurunkan bobot larva, bobot pupa, jumlah telur yang dihasilkan, dan fertilitas telur. High intensity of chemical pesticide application has become a serious concern of environmentalists in recent years, because of various negative impacts of it. Therefore, environmentally friendly techniques of controlling insect pest are needed. Recently, the use of entomopathogenic nematodes, especially Steinernema sp., has created new possibilities of promising control techniques against insect pests. The aim of this study was to evaluate the effectiveness of Steinernema sp. to A. janata larvae in laboratory. This research was conducted at the Laboratory of Insect Pathology Laboratory of Indonesian Sweetener and Fiber Crops Research Insti-tute from March to August 2011. Tests used the 2nd stage larvae of Achaea janata, the leaf eater of castor (Ricinus communis). Treatment arranged in a completely randomized design (CRD) with 4 replicates. For each test used 25 larvae which were exposed to various concentrations of Steinernema sp. Concentration of Steinernema sp. used was 0, 50, 100, 200, 300, and 400 infective juvenile/larvae. Daily mortality A. janata larvae, larval and pupal weight, the number of eggs laid, and number of hatch eggs were recorded. Steinernema sp. on concentration of 200; 300; and 400 IJ/larvae was effective to cause mortality of A. janata larvae (80–94% mortality after 48–120 hours). The higher the concentration of the nematode the higher larval mortality. Steinernema sp. with concentration of 400 IJ/ larvae was effective decreasing larval and pupal weight, the number of eggs laid, and fertility of the eggs produced.

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Biological attributes of diapausing and non-diapausing Doryctobracon areolatus (Hymenoptera, Braconidae), a parasitoid of Anastrepha spp. (Diptera, Tephritidae) fruit flies

Journal of Hymenoptera Research ◽

10.3897/jhr.78.52269 ◽

2020 ◽

Vol 78 ◽

pp. 41-56

Author(s):

Jassmin Cruz-Bustos ◽

Pablo Montoya ◽

Gabriela Pérez-Lachaud ◽

Javier Valle-Mora ◽

Pablo Liedo

Keyword(s):

Female Offspring ◽

Developmental Time ◽

Fruit Flies ◽

Pupal Weight ◽

Adult Longevity ◽

Anastrepha Ludens ◽

Starvation Resistance ◽

Flight Ability ◽

Laboratory Colony ◽

Biological Attributes

Doryctobracon areolatus (Szépligeti), a solitary endoparasitoid native to the Neotropics, attacks eggs and early instar larvae of Anastrepha fruit flies, and can enter diapause under tropical and subtropical conditions. We aimed to test if biological attributes, such as size, flight ability, starvation resistance, longevity and fecundity of diapausing individuals differ from those of non-diapausing ones. Parasitoids were obtained from a laboratory colony reared on Anastrepha ludens (Loew) larvae. Parasitized host puparia were sorted in two cohorts according to their diapause condition. Developmental time from egg to adult ranged from 18 to 31 days in non-diapausing parasitoids, and 70 to 278 days for diapausing individuals. Pupal weight and adult measurements were higher in non-diapausing than in diapausing parasitoids. There were no differences in adult longevity, starvation resistance, and emergence between diapausing and non-diapausing wasps. Flight ability and fecundity rates were greater in the non-diapausing than in the diapause cohort. The proportion of female offspring was greater in the non-diapausing cohort (42.5%), whereas in the diapausing cohort the male offspring proportion was greater (62.4%). Both cohorts produced diapause offspring, but the non-diapausing cohort produced more (26.6%) than the diapausing one (9.1%). Maternal age had a significant effect on the proportion of diapause offspring: in 26 to 34 days old non-diapausing females, 78.9% of their offspring entered into diapause. These results confirmed that diapause affects the biological attributes of D. areolatus. The observed differences contribute to better understand the diapause influence on the colonization and rearing process of this species and its use as biocontrol agent.

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