Hazem Dib | Damascus Universty (original) (raw)

Papers by Hazem Dib

Figure 1 Life stages ofStethorus gilvifrons feeding on all developmental stages ofTetranychus eva... more Figure 1 Life stages ofStethorus gilvifrons feeding on all developmental stages ofTetranychus evansi: A – Larva feeding on adult; B – Pupa; C – Adult feeding on eggs; D – Adult feeding on nymph.

Biological Control, 2020

Abstract A good knowledge of interactions between natural enemy species is necessary for effectiv... more Abstract A good knowledge of interactions between natural enemy species is necessary for effective implementation of biological control programmes. This laboratory study aimed at assessing the outcome of intraguild interactions between two generalist predators frequently observed in the colonies of the rosy apple aphid (RAA), Dysaphis plantaginea Passerini (Hemiptera: Aphididae). The level of complementarity between these two species was estimated by the comparison of their individual and combined predation on RAA. Predation by 1st (H1) to 4th (H4) instar larvae of Harmonia axyridis Pallas (Coleoptera: Coccinellidae) and 3rd (F3) and 4th (F4) instar nymphs of Forficula auricularia L. (Dermaptera: Forficulidae) was evaluated for 24 h in Petri dishes using seven different densities (5, 10, 25, 50, 75, 100 and 200) of 3rd instar nymphs of RAA. Both predator species were more voracious as their age increased. The satiation level, i.e. the highest number of consumed RAA, reached on average of 17.8, 36.3, 49.4, 79.6, 62.9 and 84.3 aphids per day for H1, H2, H3, H4, F3 and F4, respectively. In the combined treatments, there was little evidence of intraguild predation. Only 2.9% of H1 and H2 died or disappeared at low RAA densities (≤25 aphids). At the non-limiting RAA density of 200, we observed a slight agonistic interaction with 7.9% less RAA consumption when the two predators were in the same arena than the sum of their individual consumptions. However, this effect was very small and was largely outweighed by the benefits of using these two predators in combination to increase prey consumption. For the other six RAA densities, predators in combination consumed a high proportion (>90%) of RAA. Our results point to the use of combinations of these two predator species, especially of their oldest instars, as promising aphidophagous candidates in early spring against RAA.

Acarologia, 2020

The red tomato spider mite Tetranychus evansi is an important invasive pest of solanaceous plants... more The red tomato spider mite Tetranychus evansi is an important invasive pest of solanaceous plants worldwide. It has been recorded in Syria since 2011 in Latakia governorate, a Mediterranean coastal region. During survey conducted in 2019, the ladybird beetle, Stethorus gilvifrons (Mulsant) (Coleoptera: Coccinellidae) and the acarivorous gall midge, Feltiella acarisuga (Vallot) (Diptera: Cecidomyiidae) were identified in association with T. evansi colonies on tomato and black nightshade from 12 sites in Latakia. Larvae of F. acarisuga, and larvae and adults of S. gilvifrons, were observed preying on all developmental stages of T. evansi. This is the first record of T. evansi as a prey of S. gilvifrons. A literature review of Stethorus and Feltiella species previously reported in association with T. evansi on solanaceous plants is also provided.

Dans le contexte politique (reduction 50% de l’utilisation des pesticides a echeance de 2018 -Pla... more Dans le contexte politique (reduction 50% de l’utilisation des pesticides a echeance de 2018 -Plan Ecophyto) et social actuel (mise en place de modes de production plus respectueux pour l'environnement), la severite des dommages causes par le puceron cendre du pommier, Dysaphis plantaginea Passerini (Hemiptera : Aphididae), surtout en agriculture biologique, rend necessaire la mise au point de solutions alternatives s’appuyant sur le role des ennemis naturels. Nous avons donc essaye d’apporter des elements nouveaux sur la connaissance des relations entre le puceron cendre et ses ennemis naturels et sur les conditions a meme de favoriser leur action. Des suivis hebdomadaires des arthropodes presents sur les rameaux infestes par D. plantaginea, ont mis en evidence l’effet negatif des auxiliaires sur les populations de D. plantaginea, sans pour autant atteindre une veritable regulation a meme d’eviter les degâts economiques. Nous avons egalement montre l’action favorisante des four...

The Canadian Entomologist

The role of spiders (Arachnida: Araneae) in biological control programmes has received less atten... more The role of spiders (Arachnida: Araneae) in biological control programmes has received less attention than that of insect natural enemies. The aim of this two-year study was to obtain descriptive data on spider spring field population structure and dynamics. The study was carried out in one insecticide-free and four organic apple orchards in southeastern France. Rolls and bands of corrugated cardboard near the ground and shoots infested with Dysaphis plantaginea (Passerini) (Hemiptera: Aphididae) in the tree canopy were used to sample spiders. Thirty-three spider species belonging to 14 families were identified from both sampling methods. Cheiracanthium mildei Koch (Araneae: Cheiracanthiidae) was clearly the predominant arboreal spider species in aphid-infested shoots (>57%). More than half of the spiders recorded in cardboard bands belonged to three species Drassodes pubescens (Thorell) (Araneae: Gnaphosidae), Pseudeuophrys erratica (Walckenaer) (Araneae: Salticidae), and Icius ...

Http Www Theses Fr, Dec 6, 2010

International Journal of Pest Management, 2016

The Canadian Entomologist, 2016

Entomologia Experimentalis et Applicata, 2016

Journal of Insect Conservation, Feb 18, 2012

Habitat manipulation techniques improve the availability of resources required by natural enemies... more Habitat manipulation techniques improve the availability of resources required by natural enemies to increase their effectiveness. This study focused on the effects of floral strips on Hymenopteran parasitoid presence. The experiments were conducted during spring 2007 in one organic low-input apple orchard located in southeastern France. The density and the diversity of parasitic wasps collected from sown floral strips were higher than those from mown plants. The family of parasitic wasps of Braconidae was strongly dominant, followed by Mymaridae and Pteromalidae. By studying 26 flowering species, the greatest diversity and density of parasitic wasps were collected from Potentilla reptans, Achillea millefolium, Trifolium repens and Torilis arvensis. In terms of the early flowering plants, the most important results were observed in Euphorbia helioscopia, Senecio vulgaris and Veronica persica. To give an idea of the functional role of these plants, we studied the parasitic wasps of the diapausing larvae (cocoon) of codling moth Cydia pomonella. We recorded three emerged species: Ascogaster quadridentata, Pristomerus vulnerator and the hyperparasite Perilampus fulvicornis. However, none of these species have been observed on the 26 studied plants. Hence, this result may be suggesting that the studied plants do not have a functional role concerning these parasitoids. These studies may be advantageous for biological control programs in order to select flowering plant species attracting parasitic wasps specific to fruit pests.

Agriculture, Ecosystems & Environment, 2016

Biological Control, 2011

To evaluate whether aphid antagonists are suitable targets for biological approaches to control a... more To evaluate whether aphid antagonists are suitable targets for biological approaches to control aphid populations, their voracity and intraguild interactions must first be elucidated. The aim of this laboratory study was to compare two predators of the rosy apple aphid (RAA) Dysaphis plantaginea: the generalist Forficula auricularia and the specialist Episyrphus balteatus. Predation by 2nd and 3rd instar larvae of E. balteatus and 3rd and 4th instar nymphs of F. auricularia was evaluated individually and in combination for 24 h in Petri dishes. Five different densities (25, 50, 75, 100 and 200) of 1st or 3rd instar nymphs of RAA were incubated at three different temperatures (15, 20 and 25°C). Overall, the older life-stages of both predator species were more voracious than younger individuals. The two predator species did not negatively interact. Instead, when the RAA density was not limiting they had an additive effect. Although the predators consumed significantly higher numbers of RAA when the younger life-stages were offered, they fed more efficiently on the older life-stages of RAA with consumption of 1.8-to 2.7-fold higher biomass. In general, the most RAA were consumed at 20°C. Syrphids consumed more RAA at 15°C than at 25°C whereas earwigs consumed slightly more aphids at 25°C than at 15°C. Overall, the two predators consumed a constant proportion of RAA at the first four RAA densities until reaching satiation. This finding suggests that in theory they would be effective in regulating RAA numbers in early spring when field RAA populations are beginning to build up. The potency of both predators, alone or in combination, should now be tested for augmentative approaches in semi-field and field studies.

Biological Control, 2010

Efficient pest control using conservation strategies requires sound knowledge of the dynamics of ... more Efficient pest control using conservation strategies requires sound knowledge of the dynamics of the pest and its natural enemies (NE). But the role of natural regulation under natural conditions is not easy to prove. The rosy apple aphid (RAA) Dysaphis plantaginea is the most detrimental aphid in organic apple orchards. Our aim was to determine whether and to which point the abundance and composition of arthropod communities associated with aphid colonies affects RAA population dynamics. The present study, based on weekly observations of marked and infested apple shoots was carried out from April to June in 2008 and 2009 in one experimental insecticide-free apple orchard and four organic commercial orchards located in south-eastern France. NE populations were the most diverse (7.3 taxonomic groups for 50 shoots) and abundant (1.44 individuals per shoot) in the experimental orchard compared to organic orchards (3.8 groups for 50 shoots and 0.7 individuals per shoot). The large RAA populations per shoot (more by 1.7-fold) observed in two of the five orchards were presumably related to a lower number of NE (less by 1.9-fold) and a high abundance of ants (more by 6.2-fold). Among the main NE groups, syrphids arrived first, followed by coccinellids and earwigs. Parasitism rates, mainly due to Ephedrus sp. (Braconidae), were between 0.66% and 6.93%. Based on their precocity and abundance, syrphids appeared to be the most efficient group of NE under the study conditions. By surveying the same shoots weekly we could demonstrate that RAA population dynamics were strongly affected by the presence of NE. This predatory effect was however not sufficient to prevent damage to the apple trees. New management practices aimed at favoring natural regulation, especially augmentative approaches, need to be developed.

Agricultural and Forest Entomology, 2011

1 Phenological day degree models are often used as warning systems for the emergence of arthropod... more 1 Phenological day degree models are often used as warning systems for the emergence of arthropod pests in agricultural crops or the occurrence of natural enemies of the pest species. In the present study, we report on a case study of the European earwig Forficula auricularia L., which is an important natural enemy in pipfruit orchards, and describe how such a day degree model can be used to avoid negative effects of crucial orchard management, such as spray applications and soil tillage. A precise timing of these interventions in relation to the phenology of natural enemies will enhance biocontrol. 2 Earwig population dynamics are characterized by single-and double-brood populations, each with specific biological characteristics. 3 A day degree model capable of predicting the phenology of local earwig populations of both population types was developed. The model was checked for accuracy by comparing the first field observation dates of various life stages with predicted values using temperature data from the nearest weather station. In addition, variation in development time was assessed using field data. 4 The model was able to make predictions on a global scale. Although single-and double-brood populations differ in phenology, the predictions of first appearance dates were similar. Variation in development time showed that single-brood populations were more synchronized. 5 Our phenological model provides an accurate tool for predicting and simulating earwig population dynamics, as well as for enhancing the biocontrol of pests in pipfruit orchards.

... Effect of codling moth exclusion nets on the rosy apple aphid, Dysaphis plantaginea, and its ... more ... Effect of codling moth exclusion nets on the rosy apple aphid, Dysaphis plantaginea, and its control by natural enemies. ... Research highlights. ►Nets reduced the duration of the rosy apple aphid (RAA) infestation by 7 to 10 days. ...