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The most effective way to contain spread of the plant pathogen Xylella fastidiosa in Europe is to manage populations of its main insect vector, Philaenus spumarius L. (Hemiptera: Aphrophoridae). The action of some entomopathogenic endophytic fungi (EEF) on insect pests, directly through contact or indirectly by internal colonization of host plant tissues, may offer an excellent control option within integrated pest management (IPM) programmes. This study evaluated the impact of two EEF strains as control agents of P. spumarius (Metarhizium brunneum strain EAMa 01/58-Su and Beauveria bassiana strain EABb 01/33-Su [Hypocreales: Clavicipitaceae and Cordycipitaceae, respectively]); both strains were known to be excellent control agents of many other serious chewing and sap-sucking agricultural pests. First, the pathogenicity of strains applied directly to P. spumarius adults was evaluated, resulting in 50.0% and 32.0% mortality and a mean survival time of 4.7 and 6.2 days for M. brunneum and B. bassiana, respectively. Furthermore, colonization of Sonchus oleraceus by EEFs was observed after both soil and foliar applications. Greatest colonization (91.0%) was observed in plants treated with foliar applications of M. brunneum. Based on these results, we evaluated the feeding behaviour of P. spumarius on S. oleraceus plants previously colonized by M. brunneum using the ‘Electrical Penetration Graph’ technique. P. spumarius fed in a similar way on EEF-colonized and non-colonized S. oleraceus plants, with the exception that insects feeding on colonized plants reached xylem vessels faster than insects feeding on non-colonized plants. In addition, significantly higher mortality of P. spumarius was observed when feeding on plants treated by M. brunneum compared with the control. The duration of xylem ingestion events indicates that P. spumarius preferred to feed on basal leaves of the plant compared with apical leaves. Our results indicate strong potential for strain EAMa 01/58

Aim of study: To identify a new pest of jujube reported by the farmers in Spain. Area of study: The Iberian Peninsula (Spain). Material and methods: The insects were identified according to the mitochondrial cytochrome C oxidase subunit I (COI) gene and the main morphological features of this tephritid species, including the ocellar seta, the mesonotum and apical crossband in winds. Main results: Based on morphological characterization the insects were identified as Carpomya incompleta (Becker) (Diptera: Tephritidae), which was confirmed by the phylogenetic analysis with more than 94% of identity. Besides, the distance analysis showed very low intraspecific divergence in C. incompleta sequences. Research highlights: We report the presence of the zizyphus fruit fly in Spain for the first time. This presence has been reported to the Early Warning Systems on Alien Invasive Species of the Andalusian Government (Spain).

Aim of study: Entomopathogenic fungi (EPF) are biocontrol agents, plant growth promoters, and increase tolerance to biotic-abiotic stresses. In this study we investigated the factors associated to the application method, which are crucial for the interaction between the fungus and the host plant at initial crop growth stages. Area of study: The study was performed in Cordoba (Spain) Material and methods: Three experiments were performed to investigate: (i) the effect of different concentrations of the surfactant Tween® 80 (0, 0.5, 1, 5, and 10%) on wheat seed coating with conidia of Metarhizium brunneum and seed and conidia viability; (ii) the performance of wheat seedlings at first growth stages after their inoculation with Beauveria bassiana or M. brunneum via seed coating or soil drenching; and (iii) the role of soil sterilization and seed disinfection on leaf concentration of chlorophyll (SPAD) and B. bassiana or M. brunneum colonization. Main results: Tween® 80 concentration linearly improved seed coating (up to 127%) without altering wheat seeds and fungal conidia germination. Seedling length of inoculated plants was significantly increased with B. bassiana and M. brunneum (67% and 46%, respectively) via seed coating. Seed disinfection was key to achieve an enhancement in wheat SPAD (10-18%) with B. bassiana or M. brunneum concerning Control, that combined with sterilization of soil showed the highest endophyte colonization rates (up to 83.3% with both fungi) Research highlights: The surfactant concentration, application method, seed disinfection, and soil sterilization are key parameters to improve the potential benefits on the EPF-plant relationship.

Pine Wood Nematode Bursaphelenchus xylophilus causes Pine Wilt Disease (PWD), resulting in widespread tree mortality. This quarantine organism is necessarily vectored by Monochamus spp. pine sawyer beetles. PWD management through control of the insect vectors has been proposed. Recently, the high potential of entomopathogenic fungus Beauveria pseudobassiana for the biological control of M. galloprovincialis, the only known vector of the disease in Europe, has been shown. Several experiments were carried out aimed to develop a practical method to spread this biological control agent into the beetle population by self-dissemination tactics. Multiple funnel trap collection cups were provided with screened bottoms to effectively reduce by-catch of non-targeted beetles by 72%. Two self-release devices attached to the trap collection cups were field tested and resulted high level effective in allowing escape of trapped M. galloprovincialis adults. These devices were further developed to serve for the self-infection purpose. Two B. peudobassiana concentrations, [109] and [1010] conidia/g in talc powder, were assayed in two selfinfection devices in the laboratory. Survival time averaged was 4,9 days and dosis 2,7 mg·insect-1 was reported for the low dosage applied with thin device. Further studies testing horizontal transmission of self-infected beetles would extend these results., Bursaphelenchus xylophilus, cuyo vector es Monochamus galloprovincialis, provoca la enfermedad del marchitamiento del pino. Las estrategias de control se centran en el manejo del vector. En este trabajo se desarrolla un método de autodiseminación de Beuaveria pseudobassiana, hongo entomopatógeno de alta virulencia sobre M. galloprovincialis, que permita la infección sobre la población de este vector, consistente en un sistema mixto de autoliberación y autoinfección, de los insectos capturados en el bote colector de trampas multiembudos. Se intenta aumentar su selectividad reduciendo las capturas de especies de xilófagos no objetivo mediante modificaciones en el sistema: filtrado a través de mallas de fondo y alturas de conexión del dispositivo al bote. El sistema de malla ancha testado redujo en un 72% la captura de especies no objetivo. El dispositivo de autoliberación de Monochamus, un tubo enroscado externamente al bote colector, ha permitido la autoliberación de la totalidad de los insectos capturados. Se han determinado las características del dispositivo de autoinfección y la concentración del hongo entomopatógeno que pueden resultar adecuadas tras ensayar dos concentraciones: 1·109 y 1·1010 conidios·gramo-1 en talco y dos dispositivos. El dispositivo estrecho forrado internamente con fieltro fino y la dosis de 1·109 conidios·gramo-1 en talco han definido un tiempo promedio de vitalidad (4,9 días) y una cantidad de inóculo transmisible (2,7 mg·insecto-1) adecuado.