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Mungbean yellow mosaic virus (MYMV) is an important constraint in successful production of mungbean (Vigna radiata L.) in many countries, including Pakistan. The MYMV spreads by insect vector whitefly (Bemisia tabaci Gennadius). The use of resistant cultivars is the most effective management tactics for MYMV. Twenty mungbean varieties/lines were screened against insect vector of MYMV under field condition in the current study. Resistance levels for varieties/lines were assessed through visual scoring of typical disease symptoms. Furthermore, the impacts of two insecticides 'Imidacloprid' and 'Thiamethoxam' and two plant extracts, i.e., neem (Azadirachta indica), and Eucalyptus (Eucalyptus camaldulensis) were tested on the suppression of whitefly. Field screening indicated that none of the tested varieties/lines proved immune/highly resistant, while significant variations were recorded among varieties/lines for resistance level. All varieties/lines were systemically infected with MYMV. The varieties 'AARI-2006' and 'Mung-14043' were considered as resistant to MYMV based on visual symptoms and the lowest vector population. These varieties were followed by 'NM-2006' and 'NL-31', which proved as moderately resistant to MYMV. All remaining varieties/lines were grouped as moderately to highly susceptible to MYMV based on visual symptoms' scoring. These results revealed that existing mungbean germplasm do not possess high resistance level MYMV. However, the lines showing higher resistance in the current study must be exploited in breeding programs for the development of resistant mungbean varieties/lines against MYMV. Imidacloprid proved as the most effective insecticide at all concentrations to manage whitefly population. Therefore, use of the varieties with higher resistance level and spraying Imidacloprid could lower the incidence of MYMV., Competing Interests: The authors have declared that no competing interests exist.

Background and Objective: The Taify cultivar of grapevine (Vitis vinifera L.) is the second important economical fruit after pomegranate at high altitudes of the Taif region in Saudi Arabia. The grapevine trees are infested with different piercing-sucking insect pests especially aphids, whiteflies and thrips. The purpose of this study was to evaluate the ability of an indigenous endophytic entomopathogenic fungus, Beauveria bassiana to control the important piercing-sucking insect pests on grapevines., Materials and Methods: This investigation was carried out through 5, 10 and 15 day intervals between sprays for controlling Aphis illinoisensis, Bemisia tabaci and Frankliniella occidentalis with a concentration of 6×106 conidia mL-1 under field conditions., Results: The higher infestation in the untreated control was by aphids followed by whitefly and thrips. At the end of the experiment in the treated trees, aphid and whitefly reduction percentages with 5 day intervals of sprays (98.5 and 96.12%, respectively) were not significantly different from 10 day intervals (95.17 and 91.81%, respectively) while these reductions were significantly higher than the reduction occurred by 15 day intervals of sprays (65.93 and 44.51%, respectively). Meanwhile, the 3 intervals of sprays did not differ significantly in the thrips reduction occurred by them with a range from 93.62-96.46%., Conclusion: This indigenous B. bassiana as 6×106 conidia mL-1 with 10 day intervals of the spray-on grapevine can suppress the piercing-sucking insect pests. This also will participate in grapevine organic production and furthermore, it could replace the chemical treatment.

Orius albidipennis (Reuter) (Hemiptera: Anthocoridae) is a generalist predator used for biological control of insects attacking ornamental plants. Molecular identification of this species using internal transcribed spacer 1 (ITS1) of ribosomal DNA was conducted for the first time. The complete sequence of ITS1 and fragments of its flanking 18S and 5.8S rDNA genes are reported herein. The estimated length of ITS1 of O. albidipennis was 305 bp. This spacer was nearly identical to its counterpart of Orius sp-Taif strain in spite of the difference in their length. The phylogentic relationships were determined using the maximum-likelihood method supported with strong bootstrap probabilities clustering of both taxa together. Further molecular markers could be useful to identify the Taif strain and support its sister relationship to the Egyptian O. albidipennis.

Background: The cotton aphid, Aphis gossypii Glov. (Hemiptera: Aphididae), is a major insect pest on a wide range of plants that causes high damage and transmits plant viruses. This study was carried out to evaluate an indigenous isolate, Beauveria bassiana (Bb), and extracts of 5 plant species: Psiadia penninervia, Pulicaria crispa, Euryops arabicus, Salvia officinalis, and Ochradenus baccatus against A. gossypii, as individual and combined treatments to estimate their compatibility under laboratory conditions. Also, the antifungal activity of these plant extracts against B. bassiana was evaluated. Results: LC50 value was 8.64 × 104 spores/ml of Bb against A. gossypii, while LC50 values of the tested 5 plant extracts on A. gossypii were 103.64, 879.92, 747.90, 783.28, and 262.42 μg/ml for P. penninervia, P. crispa, E. arabicus, S. officinalis, and O. baccatus, respectively. Both P. penninervia and O. baccatus extracts had the highest antifungal activities against Bb and were significantly different from the other 3 plant extracts. After 24 h of treatment with the combination of Bb and each extract, no effect for these combinations on A. gossypii mortality was recorded. Meanwhile, 5 days after treatment, the combined treatments between Bb and each plant extract achieved a significant increase in mortality than that of the single treatment with Bb or plant extract, except for P. penninervia extract, which did not achieve a significant mortality increase when combined with B. bassiana than that of its single treatment. Conclusion: P. penninervia extract was not compatible with B. bassiana, but the other tested 4 plant extracts were compatible with B. bassiana. These 4 plant extracts could be used to control aphids in combinations with B. bassiana. Further laboratory and field investigations are needed to examine the effects of these plant extracts on other insect pests or associated beneficial insects. [ABSTRACT FROM AUTHOR]

The endophytic fungus, Beauveria bassiana has been found to occur endophytically in hundreds of plant species tissues and has been inoculated for establishment in different plants. It has negative effect on piercing-sucking insects in grapevine plants. Thus, the present study aimed to detect the endophytic fungus, B. bassiana throughout ITS genes analysis in the grapevine plant, Vitis venifera cv. Taify and assess its potential for controlling the grapevine aphid, Aphis illinoisensis Shimer (Hemiptera: Aphididae). The obtained 5 isolates were DNA sequenced for ITS region. Data analysis showed that there were 2 different isolates (accession number: MN900613 for isolate Bb-Taif1 and MN900614 for isolate Bb-Taif2). The values of LC50 were 6.041 × 104, 3.199 × 105 spores/ml while those of LC90 were 6.13 × 106 and 7.474 × 107 spores/ml after 3 days of treatment by Bb-Taif1 and Bb-Taif2, respectively. These values showed that the virulence of Bb-Taif1 isolate was higher in its efficacy than the Bb-Taif2 isolate. Further investigations are needed to evaluate its efficacy on other piercing sucking or chewing insect pests throughout conidia spraying, soil inoculation, and/or root immersion for grapevine plants. [ABSTRACT FROM AUTHOR]

Aphids are among the important pests causing a high damage for rose plants. They infest most of plant parts, specially leaves and flowers and are vectors for virus diseases. Orius is a generalist predator consuming aphids, other insects and mites. In the present work, Orius was used to control aphids that infest Taif's rose plants. Mass-production of the native species in the laboratory on alternative prey was done. Samples were released in the field as 10, 50 and 100 predators/rose plant. The obtained results showed that the release rate of 50 preadators/plant is efficient to control aphids pest. Molecular characterisation of native Orius sp. using Internal Transcribed Spacer (ITS)1 of ribosomal DNA was undergone for the first time. Complete sequence of ITS1 and its flanking RNA genes (18S rRNA and 5.8S rRNA) is reported in this manuscript and blasted in NCBI. [ABSTRACT FROM PUBLISHER]

Chemical insecticides have many harmful effects, including as foodborne residues and environmental contaminants, as well as side effects on natural enemies and serious risks for human health. The use of plant-derived essential oils (EOs) as effective bio-agents has become an essential component of integrated pest management. In this study, the contact toxicity, deterrent, and repellent activities were evaluated for essential oils obtained from Mentha piperita, Mentha longifolia, Salvia officinalis, and Salvia rosmarinus, grown at high altitudes in the Taif region, KSA, on Aphis punicae. Furthermore, the toxicity of these EOs against the predator Coccinella undecimpunctata was estimated. A total of 17, 14, 16, and 26 compounds were identified in the EOs of M. piperita, M. longifolia, S. officinalis, and S. rosmarinus, respectively. They showed a variation in the major compounds: M. piperita (Carvone, 61.16%), M. longifolia (Pulegone, 48.6%), S. officinalis (Eucalyptol, 33.52%), and S. rosmarinus (α-pinene, 36.65%). A contact toxicity test on A. punicae imago and C. undecimpunctata larvae showed that LC50 were approximately four-fold greater for all tested EOs towards aphids compared to towards the predator, while the two species of Salvia sp. were more effective than the other two species of Mentha sp. The LC50 values on A. punicae ranged from 1.57 to 2.97 µg/mL, while on C. undecimpunctata larvae, they ranged from 5.96 to 10.33 µg/mL. Furthermore, the EOs of two species of Salvia sp. showed excellent repellence and deterrence against A. punicae. In conclusion, the tested EOs, especially those from Salvia sp., have been shown to be promising natural aphicides, repellent, and deterrent against A. punicae, and they are safe for important insect predators. [ABSTRACT FROM AUTHOR]

Whiteflies, Bemisia tabaci Gennadius (Aleyrodidae: Hemiptera), are a polyphagous economically destructive pest of several solanaceous crops around the world. Many secondary metabolites are synthesized by different biotrophic and necrotrophic fungi which are capable of inducing systemic resistance in plants against various phytophagous pests. The present laboratory work demonstrated the anti-insect impact of a protein extracted and purified partially from an entomopathogenic fungus (EPF) Lecanicillium lecanii (Zimmermann) against B. tabaci. Three different concentrations (i.e., 7.43, 11.15, and 22.31 μg mL−1) of this protein were bioassayed to assess its effect on the fecundity rate of B. tabaci on cotton (Gossypium hirsutum L.) plants. Furthermore, the possible implication of this fungal protein in defense pathways of cotton plants was evaluated by determining the expression profiles of salicylic acid (SA) and jasmonic acid (JA) pathways related to major genes through reverse transcription qPCR (RT-qPCR). According to the results, all protein concentrations exerted a significant (F3, 252 = 62.51; p ≤ 0.001) and negative impact on the fecundity rate of B. tabaci females. At the highest protein concentration (22.31 μg mL−1), the minimum rate of fecundity (i.e., 2.46 eggs female−1day−1) of B. tabaci was noted on the seventh day, whereas fecundity rates for the other two protein concentrations (i.e., 11.15 and 7.43 μg mL−1) were, respectively, 3.06 and 3.90 eggs day−1 female−1. The maximum rate of fecundity (6.01 eggs female−1day−1) was recorded in untreated (control) treatments. In addition, the foliar application of L. lecanii derived protein significantly upregulated all SA linked genes (OPR3, PPO1 and COI1) and slightly triggered up the JA linked genes (LOX1, UBQ7 and AOS) in the cotton plants. These findings revealed that this L. lecanii extracted partially purified protein triggered systemic resistance against B. tabaci in the cotton plants, proposing its putative effectiveness as an innovative biological control technique against B. tabaci and other phloem-feeding hemipteran pests. Nevertheless, further investigations such as purification and molecular and functional characterization of this L. lecanii-derived partially purified protein are required. [ABSTRACT FROM AUTHOR]

The rose aphid, Macrosiphum rosae L. (Hemiptera: Aphididae), is an important insect pest of rose plants because it damages the leaves and flowers. The entomopathogenic fungus, Beauveria bassiana Balsamo (Vuillemin), is environmentally safe in comparison with the chemical pesticides. The indigenous fungal isolates can be the best options in biological control because they are more adapted to the local environment. In the present study, four genetically different isolates of B. bassiana (isolates 1, 2, 3, and 4) were used to estimate LC50 for the rose aphid. Also, the same isolates were used to control the aphid's infestation on rose plants in the field, and the efficacy was compared with a commercial strain (Naturalis®) with two concentrations for each isolate (2.3 × 106 and 4.6 × 106 conidia/ml). Bioassay results indicated that isolate 1 differed significantly (LC50 = 6.46 × 104) than the other three ones (LC50 = 1.46 × 105, 1.52 × 105, and 1.71 × 105). In field trials, the concentration of 4.6 × 106 conidia/ml, for indigenous as well as commercial strains, achieved the highest reductions of rose aphid infestation and the highest extraction of rose oil. Thus, this fungus can be recommended in organic rose production. Further investigations are needed for the improvement in utilization of these isolates with regard to UV radiations in the field. [ABSTRACT FROM AUTHOR]

Background: The life history and predation rate of the ladybird beetle, Harmonia dimidiata Fabricius (Coleoptera: Coccinellidae) were compared at four different temperatures (16, 20, 24, and 28 °C). The beetles were fed on the bird cherry-oat aphid, Rhopalosiphum padi Linnaeus (Hemiptera: Aphididae) and investigated at 70 ± 10% RH with a photoperiod of 14:10 h (L:D). Results: The reproductive rates (R0) were 20.07, 51.37, 66.95, and 14.54 beetle offspring at 16, 20, 24, and 28 °C, respectively. Results indicated that temperature had good impacts on the feeding potential, development, survivorship and fecundity, especially at 24 and 28 C compared with the other tested temperatures. In addition, the jackknife and bootstrap techniques were employed to estimate the population parameters' means. The obtained means of R0 and other population parameters, using the bootstrap technique fit a normal distribution. Meanwhile, the jackknife technique generated biologically meaningless zero values for R0. Both finite and predation rates were incorporated into limited predation rates for comparison of predation potential. Conclusion: Both of the growth and predation rates indicated that H. dimidiata is more effective biocontrol agent for R. padi at 24 and 28 °C than at 20, 16 °C. [ABSTRACT FROM AUTHOR]

Background: As different biogeographic strains and isolates of entomopathogenic fungi vary in their genetic, enzymatic and pathogenic characteristics, this study assessed the virulence of 2 indigenous strains of Beauveria bassiana (Balsam) Vuillemin and Metarhizium anisopliae (Metschn.) Sorokin (Ascomycota, Hypocreales: Clavicipitaceae), isolated from naturally infected insect cadavers, against the 3rd instar nymphs of Myzus persicae (Sulzer) (Hemiptera: Aphididae) and 3rd instar larvae of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) using leaf-dip and larval-dip methods, respectively. Results: Both fungal isolates exhibited considerable pathogenicity against M. persicae and S. frugiperda. Mortality in all bioassays was conidial concentration and exposure time dependent and increased significantly along with both factors (R2 = 0.86–0.99 for B. bassiana and 0.82–0.94 for M. anisopliae). Moreover, M. anisopliae isolate appeared more virulent to S. frugiperda larvae than B. bassiana isolate, while the later fungal isolate was more lethal to M. persicae nymphs than the former one. At the highest conidial concentration (1.0 × 109 conidia/ml), M. anisopliae caused maximum mean mortality of S. frugiperda (88%) and M. persicae (65%) and B. bassiana exhibited maximum mean mortality of S. frugiperda (76%) and M. persicae (94%). Moreover, probit regression analyses showed LT50 values for M. persicae of 4.57 and 6.86 days at 1.0 × 109 conidia/ml for the isolates of B. bassiana and M. anisopliae, respectively, while LC50 values were 7.75 × 106 and 8.70 × 107 conidia/ml after 10th day of application, for the isolates of B. bassiana and M. anisopliae, respectively, against M. persicae. Similarly, LT50 values for S. frugiperda were 7.75 and 7.03 days for 1.0 × 109 conidia/ml concentration and LC50 values were 2.84 × 107 and 8.84 × 105 conidia/ml at 10th day data for the isolates of B. bassiana and M. anisopliae, respectively. Conclusion: Overall study results demonstrated the effectiveness of B. bassiana and M. anisopliae against M. persicae and S. frugiperda, respectively. However, field evaluations of these indigenously isolated promising fungal strains against these insect pests. [ABSTRACT FROM AUTHOR]