Risk of damage to tomato crops by the generalist zoophytophagous predator Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae)

AbstractNesidiocoris tenuis (Reuter) (Hem. Miridae) is a native zoophytophagous predator of the Mediterranean region, and its populations colonize tomato crops when they are not heavily treated with insecticides. This generalist predator has a high capacity for controlling insect pests, and it is currently commercially produced and released in some areas to control Bemisia tabaci (Gennadius) (Hem. Aleyrodidae). However, its status as a pest and/or as beneficial is controversial. Therefore, the aim of this study was to evaluate the risk of damage to tomatoes in extreme conditions of prey scarcity, as well as high predator populations. Three predator densities were tested in a greenhouse cage experiment during a summer tomato crop. The crop did not display any negative effect caused by the predators during the first six weeks of interaction, independently of the density released. However, subsequently, the effect was dramatic, both on the vegetative growth of the plant and on the production of fruits. The reduction in vegetative growth was located at truss eight and it was expressed mainly by a lower number of leaves and a shorter length of the shoot above the truss. There was a significant reduction of yield with a lower number of fruits collected and a smaller mean weight, although this was not observable until truss seven. It seems that feeding on the plant by this mirid bug competed with the vegetative growth and fruiting processes of the plant in the extreme conditions of prey shortage maintained in our experiment.

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Effects of sticky traps on Dacnusa sibirica, Diglyphus isaea and Nesidiocoris tenuis

ENTOMOLOGIA HELLENICA ◽

10.12681/eh.10444 ◽

2017 ◽

Vol 25 (1) ◽

pp. 1

Author(s):

Dionysios Ch. Perdikis ◽

Konstantina A Arvaniti ◽

Dimitrios M Papadimitriou

Keyword(s):

Generalist Predator ◽

Mass Trapping ◽

Blue Colour ◽

Leaf Miners ◽

Tomato Crop ◽

Sticky Traps ◽

Diglyphus Isaea ◽

Effective Predator ◽

Nesidiocoris Tenuis ◽

The Difference

The potential of commonly used sticky traps (yellow, blue and transparent) to attract the two major natural enemies of the leaf miners, Dacnusa sibirica Telenga (Hymenoptera: Braconidae) and Diglyphus isaea (Walker) (Hymenoptera: Eulophidae) was recorded. In addition, we studied their efficacy to capture the effective predator Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) which in high population levels may cause damage on tomato crop. The captures of D. sibirica and D. isaea were negligible. Captures of N. tenuis adults were significantly higher on yellow and blue colour traps than on transparent traps. The difference of captures between yellow and blue traps was not significant. Furthermore, the effectiveness on N. tenuis was much increased when the traps were established next to the tomato plant apex. The results show that the use of coloured sticky traps and release of the leafminer parasitoids may be combined. Furthermore, it was clearly shown that sticky traps may not be compatible with the release of the generalist predator N. tenuis; however, yellow and blue traps should be further evaluated for its mass trapping.

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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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Effectiveness of Biopesticide Derived fromCassia spectabilis and Nicotiana tabacum Leaves Against the Main Insect Pests of Coffee and Its Effect On Other Arthropods

Pelita Perkebunan (a Coffee and Cocoa Research Journal) ◽

10.22302/iccri.jur.pelitaperkebunan.v22i1.27 ◽

2006 ◽

Vol 22 (1) ◽

Author(s):

Soekadar Wiryadiputra

Keyword(s):

Nicotiana Tabacum ◽

Insect Pests ◽

Block Design ◽

Monthly Interval ◽

Planococcus Citri ◽

Hypothenemus Hampei ◽

Botanical Pesticide ◽

Cassia Spectabilis ◽

Negative Effect ◽

Mealy Bug

An experiment on the effectiveness of biopesticide made of ramayana (Cassia spectabilis) and tobacco leaves (Nicotiana tabacum) it called as Casnic, on Hypothenemus hampeiand Planococcus citriand its effect on the arthropods population fauna in coffee plantation had been conducted in Pest Laboratory of Indonesian Coffee and Cocoa Researh Institute and Bangelan Plantation in Malang. The treatment consisted of three level concentrations of botanical pesticide(15 ml, 30 ml, and 60 ml/lof water), Beauveria bassiana(at a dose 100 g spore per ha), metidation spraying (2 ml formulation per litre of water) and two control treatments (with and without soap). The field experiment was arranged in randomized complete block design (RCBD) with four replications. The results showed that botanical pesticide at the concentration of 30.0 ml stock solution per litre of water and applied four times with monthly interval was effective in controlling coffee berry borer (Hypothenemus hampei) and coffee mealy bug (Planococcus citri). The effectiveness was not significantly different compared to metidation and Beauveria bassianaat the dose of 0.8 l and 100 g formulation per ha per application. Application of the botanical pesticide did not show negative effect on the usefull predatory insects and other arthropods population in coffee ecosystem. Key words : Botanical pesticide, Cassia spectabilis, Nicotiana tabacum, Coffee, Hypothenemus hampei, Planococcus citri, Arthropods.

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Comparative Effects of Rice and Melon Wastes on Sitophillus Zeamais, Storage Pest of Maize Grains in Nigeria

Journal of Experimental Agriculture International ◽

10.9734/jeai/2021/v43i130638 ◽

2021 ◽

pp. 114-123

Author(s):

R. T. Olorunmota ◽

T. I. Ofuya ◽

J. E. Idoko ◽

B. A. Ogundeji

Keyword(s):

Rice Husk ◽

Rice Husk Ash ◽

Insect Pests ◽

Adult Emergence ◽

Application Rates ◽

No Weight Loss ◽

Negative Effect ◽

Males And Females ◽

Maize Grain ◽

Treatment Mortality

World’s calories supply from maize accounts for 20% but global postharvest grain loss caused by insect pests was estimated to be 10%. Control is mostly by synthetic insecticides with consequences such as insect resurgence and resistance and negative effect on non- target organisms. Maize grain losses to weevils are so enormous that effective local solution has to be sought. Thus this research aimed at assessing the effectiveness of powders and ash of rice husk and melon shell in controlling Sitophillus zeamais (Mots) in stored maize. Four treatments, Rice husk powder (RHP), Rice husk ash (RHA), Melon shell powder (MSP) and Melon shell ash (MSA) were applied at eight levels of 0 - 2.0 g 20 g-1 maize grain in three replicates. Five pairs (males and females) of freshly emerged S. zeamais were introduced into each treatment. Mortality test was carried out on the insects at 48 and 96 hours after introduction. Germination test was conducted on ten randomly selected grains after weevil emergence. Significantly higher (p≤0.05) mortality was recorded in treated seeds than the control. Virtually 100% mortality of S. zeamais was attained in both RHA and MSA treated maize in 96hrs at all application rates. Mean adult emergence in maize treated with both RHA and MSA were zero, with no weight loss like those of grains treated with standard control of P. guinensis. Also maize grain treated with Rice husk ash (RHA) and Melon shell ash (MSA) recorded a mean WPI of zero irrespective of application rates as in P. guinensis. The mean percentage germination of maize grain was significantly higher (p≤0.05) in P. guinensis than those recorded on treatments, while germination of treated maize is higher than the control. Thus rice husk and melon shell are effective alternatives to insecticides against S. zeamais in stored maize.

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Effect of Different Substrate on Growth of African Violet (Saintpauila ionantha) Grown in Greenhouse Conditions

HortScience ◽

10.21273/hortsci.31.4.657c ◽

1996 ◽

Vol 31 (4) ◽

pp. 657c-657

Author(s):

M. Arias-Gonzalez ◽

J. Farias ◽

S. Guzman ◽

A. Michel

Keyword(s):

Experimental Design ◽

Vegetative Growth ◽

High Capacity ◽

Peat Moss ◽

Leaf Color ◽

Potted Plants ◽

African Violet ◽

Black Clay ◽

Randomized Experimental Design ◽

Compost Soil

Our purpose was to evaluate the vegetative growth and flowering of African violet (Saintpauila ionantha) grown in seven soils subtrates under greenhouse conditions. The following were tested: river lime, pine ushers, black clay, oak soil, peatmoss, Canadian peatmoss, and a compost soil. Pots were in a fully randomized experimental design with seven treatments, and four replications was used. A monthly 10N–20P–10K fertilization was applied to potted plants. The study lasted for 135 days, taking data every 15 days on leaf perimeter, length and elasticity of the petiole, plant height, and leaf color. Best vegetative growth was observed with oak and canadian peat moss due to their high capacity to hold water and their very good aeration. Least vegetative growth was observed with black clay, where plants failed to flower. Other substrates did not show differences in plant growth.

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Tomato hybrids with complex resistance for ground greenhouses

Kartofel` i ovoshi ◽

10.25630/pav.2021.34.51.006 ◽

2021 ◽

pp. 34-37

Author(s):

Т.А. Терешонкова ◽

Р.А. Багров ◽

М.Г. Фомичева ◽

Н.Ф. Тенькова ◽

Е.В. Титова ◽

...

Keyword(s):

Resistance Genes ◽

Frankliniella Occidentalis ◽

Insect Pests ◽

Western Flower Thrips ◽

Field Resistance ◽

Tuta Absoluta ◽

Pcr Analysis ◽

Sources Of Resistance ◽

Tomato Crop ◽

Breeding Material

На фоне усиливающейся инфекционной нагрузки на культуру томата, обусловленной появлением новых болезней и новых физиологических рас традиционных патогенов, возрастает значение создания и использования в производстве гетерозисных гибридов с комплексной устойчивостью. Возрастает вредоносность новых насекомых-вредителей культуры томата. По вредоносности выходят на первое место томатная минирующая моль (Tuta absoluta) и западный цветочный трипс (Frankliniella occidentalis), который помимо нанесения прямого ущерба культуре выступает как переносчик вирусных заболеваний, в том числе вируса бронзовости (TSVW). Начатая селекционная программа на полевую устойчивость томата к трипсу позволила в 2020–2021 годах выделить восемь источников устойчивости среди образцов различных товарных групп. В результате двадцатилетней селекции созданы коммерческие гибриды с различным набором генов устойчивости. В задачи современной селекции входят этапы оценки и отбора селекционного материала на наличие генов устойчивости в генотипах методами ПЦР-диагностики, а также контроль устойчивости путем испытания материала в условиях инфекционных фонов или искусственного заражения. Важный этап – контроль товарных партий семян на присутствие генов устойчивости. Результаты ПЦР-анализа коммерческих гибридов на четыре гена устойчивости в сочетании с испытанием полевой устойчивости к кладоспориозу на сильном многолетнем инфекционном фоне приведены в табличной форме. Результаты показывают, что практически во всех товарных группах есть гибриды с устойчивостью к кладоспориозу, фузариозному увяданию, вирусу томатной мозаики (ВТоМ) и галловой нематоде. Также была обнаружена относительная устойчивость к фитофторозу у гибрида F1Изящный (Ph2\Ph2). Сегодня проводится работа по расширению числа генов для ПЦР-анализа селекционного материала. Under conditions of the increasing infectious load on the tomato crop due to the emergence of new diseases and new physiological races of traditional pathogens, the importance of creating and growing heterotic hybrids with complex resistance is increasing. The harmfulness of new insect pests of tomato culture is also increasing. In terms of harmfulness, the tomato mining moth (Tuta absoluta) and the western flower thrips (Frankliniella occidentalis) take the first place, which, in addition to causing direct damage to the culture, is a carrier of viral diseases, including Tomato spotted wilt virus. The started breeding program for the field resistance of tomato to thrips made it possible for the period 2020–2021 to identify 8 sources of resistance among the samples of various commodity groups. As a result of 20 years of selection, commercial hybrids with different sets of resistance genes have been created. The goals of modern breeding include breeding material assessment and selection for the presence of resistance genes in genotypes by PCR diagnostics method, as well as control of resistance by testing the material under infectious backgrounds or artificial infection inoculation. Another important step is the control of commercial seed lots for the presence of resistance genes. The results of PCR analysis of commercial hybrids for 4 resistance genes in combination with the test of field resistance to Cladosporium fulvum under condition of strong long-term infectious background are given in tabular form. These results show that in almost all product groups there are hybrids with resistance to ToMV, in combination with other resistances, including the relative resistance to late blight in the F1 Iziyaschniy (Ph2\Ph2) hybrid. Currently, the progress is being made towards expanding the number of genes for PCR analysis of breeding material.

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Effect of Silicon fertilization on two major insect pests of tomato under greenhouse conditions

10.21203/rs.3.rs-205218/v1 ◽

2021 ◽

Author(s):

Aqeel Alyousuf ◽

Dawood Hamid ◽

Mohsen A. Desher ◽

Amin Nikpay ◽

Henk-Marten Laane

Keyword(s):

Population Density ◽

Insect Pests ◽

Insect Pest ◽

Tomato Leaf ◽

Leaf Miner ◽

Pest Species ◽

Tomato Crop ◽

Soil Drench ◽

Tomato Leaf Miner ◽

Acid Formulation

Abstract Tomato (Solanum lycopersicum L) is an important vegetable crop in Iraq. This horticultural crop is attacked by several insect pest species. Among them, the whitefly Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) and the tomato leaf miner Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) are the major threat of greenhouse tomatoes in Basrah province in south Iraq. The management of these pests is heavily based on application of chemical pesticides. Vast application of pesticides caused harmful damage to the environment, human health and may increasing the risk of pest resistance on insect populations. One of the promising strategies which are compatible with organic farming is application of silicon for enhancing plant vigor and resistance to pest damage on various agricultural crops. Due to these facts, the experiments have been carried out at Basrah University to evaluate the effects of silicon (Si) fertilization on tomato plants for reducing damage of these two major pests. Treatments comprised two type of Si applications (Soil drench treatment and foliar spraying) with four Si concentrations (0, 0.5, 1 and 2%) of AB Yellow ® silicic acid formulation. The population density of B. tabaci and T. absoluta were studied weekly during the growth season. The results clearly demonstrated that Silicon applications significantly decreased the population of immature of both whiteflies and tomato leaf miner on tomato crop in the greenhouse; Si-Foliar spraying was more effective in reducing the population density of these key pests compared to Si- soil drench application.

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Is repeated cypermethrin fumigation dangerous for the mitochondrial DNA in dry insect samples?

Acta Entomologica Musei Nationalis Pragae ◽

10.2478/aemnp-2018-0051 ◽

2018 ◽

Vol 58 (2) ◽

pp. 609-614

Author(s):

Dominik Vondráček ◽

Michal Tkoč ◽

Martin Fikáček

Keyword(s):

Mitochondrial Dna ◽

Insect Pests ◽

Negative Control ◽

Phylogenetic Studies ◽

Standardized Protocol ◽

Pcr Product ◽

Negative Effect ◽

Source Tissue ◽

Short Time

Abstract Entomological collections are the target of various insect pests, e.g. carpet beetles (Dermestidae) and booklice (Psocoptera) which can damage and completely destroy dry specimens in a relatively short time. Collections in the National Museum, Czech Republic (NMP) including the entomological ones are protected by fumigation using commercially available smoke shells ‘Cytrol Super SG’; fumigation is performed twice a year. The active insecticidal substance of these smoke shells is cypermethrin (6.25%). We tested whether the repeated cypermethrin fumigation of the NMP entomological collections negatively affects the quality of mitochondrial DNA in dry specimens and prevents the subsequent use of these samples for molecular analyses required for identification, taxonomy, systematics, and phylogenetic studies. We used 32 freshly fixed specimens of the flower chafer Oxythyrea funesta (Poda von Neuhaus, 1761) and 32 freshly fixed specimens of the brown-tailed cockroach Supella longipalpa (Fabricius, 1798). One half of specimens of both species was stored outside NMP and not fumigated (negative control), and the other half was deposited in collection hall with the NMP insect collection and directly exposed to the fumigation. Subsequently, all specimens were processed in a molecular laboratory under a standardized protocol using one leg as the source tissue after each fumigation, and the 658 bp long barcoding region of the cytochrome oxidase I (cox1) as the testing gene fragment. Results of the PCR product electrophoresis and the sequences acquired confirmed that the repeated fumigation had no negative effect on tested samples.

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Does capacity increase compliance? Examining evidence from European cooperation against air pollution

International Environmental Agreements Politics Law and Economics ◽

10.1007/s10784-020-09497-1 ◽

2020 ◽

Author(s):

Andreas Kokkvoll Tveit

Keyword(s):

Air Pollution ◽

High Capacity ◽

International Agreements ◽

European Cooperation ◽

Capacity Increase ◽

Policy Goals ◽

Negative Effect

Abstract Scholars commonly hypothesize that enhanced capacity—improved ability to do as agreed—increases states’ compliance with international agreements. In contrast, using a novel dataset that covers 31 states and three decades of cooperation, I find a negative effect of capacity on compliance. To help explain this seemingly counterintuitive finding, I offer a novel conjecture of the capacity–compliance relationship. In particular, I argue that the effect of capacity may vary substantially across states, because states’ intention to comply constitutes a crucial intervening variable. Among reluctant states pursuing policy goals that affect compliance negatively, high capacity may in fact cause noncompliance. I exemplify the conjecture through evidence from a high-capacity noncompliant state (Norway).

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