Besides the effect of zeolites against plant diseases and insect pests, zeolites may also have beneficial effects for the treated plant itself. Zeolites are able to adsorb CO2, which may influence photosynthesis. Zeolites may also reduce leaf temperature by reflecting the infrared radiation. These properties lead to a reduction of transpiration rate, which may improve the water-use efficiency, the yield and the fruit quality. In this study, the possible beneficial effects of zeolites on plant growth, dry weight, water uptake and photosynthesis are described. Despite the fact that little or no effects were observed for plant growth, water uptake and dry weight, some effects were noticed for the photosynthesis. A clear trend could mainly be observed for the treated apple trees, i.e. an increase of photosynthesis was observed after treating the apple trees with the zeolites, followed by a decrease after two weeks.

Abstract:The high versatility and ease of electrospinning of polymer solutions have recently resulted in electrospun fibers which are of interest for a wide variety of chemical and biomedical applications. This is partially due to the high surface area of the fibers which is attractive for the detection and capture of (bio)chemicals. In the present work, polystyrene (PS) fibers were electrospun and coated with cationic poly(allylamine hydrochloride) (PAH) or anionic dextran sulfate (DSS). The fibers were physicochemically characterized. Upon incubation in a dispersion of inactivate HIV-1, avid binding of HIV to all types of fibers occurred. By atomic force microscopy and spatial selective photobleaching, the binding of the inactivate HIV-1 particles to the fibers could be confirmed. Interestingly, all fibers but especially the DSS-and PAH-coated ones resulted in a significant reduction of infection of CD4 + TZMb1 cells by replication-competent HIV-1. On top, DSS-coated PS fibers were not toxic for vaginal epithelial cells which may make these fibers of potential interest to inhibit HIV infection in the context of topical prevention.2

(1) Background: The tomato leafminer Tuta absoluta (Lepidoptera: Gelechiidae) is a key tomato insect pest. At present, it is considered to be a serious threat in various countries in Europe, North Africa, and Middle East. The extensive use and the developed resistance of T. absoluta to spinosad causes some concern, which leads to the need for alternative products. (2) Materials and Methods: Several laboratory experiments were conducted to investigate the ovicidal properties of a zeolite particle film on T. absoluta. The toxicity of three different zeolites and six zeolite formulations to T. absoluta eggs and larvae was determined using different exposure methods. (3) Results: In general, the formulated zeolites yielded higher egg and larvae mortality values, especially when the zeolite particle film was residually applied. Notable differences in mortality rates from exposure to zeolites compared to other products, such as kaolin, its formulated product Surround, and the insecticide spinosad, were observed. Kaolin and Surround exhibited little or no effect for both application methods, while the hatch rate was reduced by 95% when spinosad was applied topically. Spinosad yielded egg and larvae mortality rates of 100% for both application methods. Additionally, increased oviposition activity was observed in adults exposed to the wettable powder (WP) formulations. These WP formulations increased egg deposition, while Surround and spinosad elicited a negative oviposition response. (4) Conclusions: It can be derived that the tested products, zeolites BEA (Beta polymorph A), FAU (Faujasite), LTA (Linde type A), and their formulations, had no real insecticidal activity against the eggs of T. absoluta. Nevertheless, egg exposure to zeolites seemed to affect the development process by weakening the first instar larvae and increasing their mortality. Subsequently, based on the choice test, no significant difference was observed between the number of eggs laid on the treated leaves and control leaves.

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Resistance to pesticides has been studied in several insect pests, but information on the natural enemies of pests-including the Neotropical predator Chrysoperla externa Hagen (Neuroptera: Chrysopidae), a major biological control agent in South America-is lacking. We report here a comparative study between a field-collected strain of C. externa subjected to monthly sprayings of pyrethroids and neonicotinoids and a laboratory strain without exposure to pesticides. The tolerance of both strains against zeta-cypermethrin was similar, and addition of the synergist piperonyl butoxide increased the toxicity by 30% in both strains. Gas-chromatography analyses and mixed-function-oxidase measurements indicated similar values in both strains and also confirmed the key role of oxidative metabolism in this species. Because C. externa has maintained a tolerance to zeta-cypermethrin without previous pesticide exposure, this species could potentially be mass-reared and released in fields in the presence of pesticide pressure.