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Ivermectin and fipronil have been used regularly to control the hard tick Hyalomma anatolicum (Acari: Ixodidae) in domestic ruminants for more than a half-decade in Balochistan, Pakistan. Inappropriate and indiscriminate use of these acaricides has resulted in the development of resistances in tick species. In this work, acaricides (ivermectin and fipronil) resistance was evaluated in H. anatolicum through in vitro and in vivo bioassays in a horse farm of Quetta, Balochistan province, Pakistan. A participatory epidemiological survey was conducted to assess potential risk factors associated with the development of acaricide resistance in H. anatolicum. The results of the epidemiological survey revealed that the horse keepers did not follow the manufacturer's instructions for the use of acaricides and applied indiscriminate doses of acaricides. The results of in vitro bioassays (adult immersion test and larval immersion test) showed that fipronil and ivermectin have protective efficacy against H. anatolicum. The results of in vivo bioassay (adult-tick mortality assay) revealed that fipronil had a higher efficacy (78.16%) than ivermectin (49.94%). More than 80% of tick mortality was not achieved in any bioassays, even for the highest acaricide concentration (100 ppm), which suggests the development of acaricide resistance against fipronil and ivermectin. This study highlights the urgency to implement a country-wide awareness about resistance monitoring and effective tick control. [ABSTRACT FROM AUTHOR]

The loss of individuals in disturbed sites may be buffered by the presence of small natural features (SNFs), sites acting as ecological refuges preventing the loss of phenotypic variability and genetic diversity of plants. An important group of SNFs is rocky outcrops, singular geological formations that stand out from the surrounding matrix which could host a greater species diversity. We tested the value of rocky outcrops as SNFs of a Tertiary relict tree, the Chilean lucuma Pouteria splendens (Sapotaceae). We identified vegetation patches with P. splendens and characterized their landscape properties in sites associated with rocky outcrops and clearings (plains). Then, we contrasted the genetic diversity, phenotypic variability and sapling abundance of P. splendens inhabiting rocky outcrops and plains. We observed that rocky outcrops sustained subtle higher genetic diversity compared with plains, but non-significant genetic structuration was detected between habitat types. Independently of the habitat type, P. splendens have a significant role in the sapling recruitment: their number was higher underneath of conspecifics than in open spaces. Besides, plants in the rocky outcrops produced smaller and ovoid-shaped fruits, as a possible result of selective pressures generated by frugivorous. We propose that rocky outcrops are regeneration sites for P. splendens. However, subtle differences in genetic diversity between habitats and the lacking of genetic structuration suggest that conservation strategies should be focused on the protection of all habitat types as a manner of maintaining ecosystem processes in this singular vegetation remnant. [ABSTRACT FROM AUTHOR]

Symbiosis in insects has been recognized as contributing to their ecological and evolutionary success. In the case of agricultural pests, endosymbionts may help insects colonize and expand their niches, allowing them to use different crops and to confront climatic variation. Moreover, endosymbionts provide improved defences against pathogens, predators, and parasitoids. In aphids, facultative endosymbionts have been found capable of generating these characteristics. However, evidence for this has been gathered from only a few model organisms. Here, we studied the effect of the facultative endosymbiont Regiella insecticola on the predation of Sitobion avenae clones by the ladybird Hippodamia variegata. In the laboratory, we assessed the predation rate of this coccinellid and the concomitant anti-predator behaviour of S. avenae with and without R. insecticola. We also evaluated the effect of the presence of this endosymbiont on the constitutive levels of E-β-farnesene, on the metabolic rate, and on the reproductive performance of S. avenae. All these traits were studied on two common alternative crops: wheat and barley. We found that R. insecticola-infected aphids were more predated irrespective of host plants and did not improve defences against coccinellid predators or metabolic rates on any host plants. Levels of E-β-farnesene were higher on wheat plants, irrespective of the presence of R. insecticola. Interestingly, R. insecticola-infected aphids had increased performance on wheat, while the opposite was true on barley. We discuss our findings based on the importance of secondary symbionts as providers of traits allowing aphids to be very invasive crop pests worldwide. [ABSTRACT FROM AUTHOR]

Plants produce secondary metabolites related to ecologically relevant processes. These compounds include surface secretions such as latex, mucilage and resins that help plants face abiotic and biotic environmental threats such as drought, nutrient deficiency, extreme temperatures and UV radiation, as well as herbivory, pathogenic microorganisms and other natural enemies. We studied the resinous coating found on involucral bracts of Haplopappus platylepis Phil. (Asteraceae). This plant belongs to a speciose genus widely distributed in South America (Lane and Hartman in Am J Bot 83:356, ). H. platylepis is characterized by resinous fragrant leaves. In this species, resins cover the involucral bracts as well as young leaves and are also secreted on reproductive stalks in smaller amounts. We carried out chemical analysis and natural history observations in order to identify whether arthropods caught in inflorescence resin differed from the ones freely visiting floral disks. Regarding bracteal adhesive's chemistry, we identified a mixture of diterpenoids and flavonoids; these compounds form a dense surface resin layer, especially over inflorescence's bracts. In relation to associated arthropods, we found a marked difference in the main organisms captured by bracteal resin compared to insects we observed foraging on disk florets; Arthrobracus (Coleoptera: Melyridae) and Linepithema (Hymenoptera: Formicidae) were the predominant insects 'trapped in resin', while Diadasia (Hymenoptera: Apidae) was the most frequent 'floral visitor'. We propose that bracteal resin of H. platylepis may function as a selective trap for non-mutualistic insects reaching reproductive structures of this plant and discuss other multiple possible roles for this secretion, including protocarnivory. [ABSTRACT FROM AUTHOR]

The author would like to include the following changes in the published article. [ABSTRACT FROM AUTHOR]