Exploitation of FTA cartridges for the sampling, long-term storage, and DNA-based analyses of plant-parasitic nematodes.

The use of DNA-based analyses in molecular plant nematology research has dramatically increased over recent decades. Therefore, the development and adaptation of simple, robust, and cost-effective DNA purification procedures are required to address these contemporary challenges. The solid-phase-based approach developed by Flinders Technology Associates (FTA) has been shown to be a powerful technology for the preparation of DNA from different biological materials, including blood, saliva, plant tissues, and various human and plant microbial pathogens. In this work, we demonstrate, for the first time, that this FTA-based technology is a valuable, low-cost, and time-saving approach for the sampling, long-term archiving, and molecular analysis of plant-parasitic nematodes. Despite the complex structure and anatomical organization of the multicellular bodies of nematodes, we report the successful and reliable DNA-based analysis of nematode high-copy and low-copy genes using the FTA technology. This was achieved by applying nematodes to the FTA cards either in the form of a suspension of individuals, as intact or pestle-crushed nematodes, or by the direct mechanical printing of nematode-infested plant tissues. We further demonstrate that the FTA method is also suitable for the so-called "one-nematode-assay", in which the target DNA is typically analyzed from a single individual nematode. More surprisingly, a time-course experiment showed that nematode DNA can be detected specifically in the FTA-captured samples many years after initial sampling occurs. Collectively, our data clearly demonstrate the applicability and the robustness of this FTA-based approach for molecular research and diagnostics concerning phytonematodes; this research includes economically important species such as the stem nematode (Ditylenchus dipsaci), the sugar beet nematode (Heterodera schachtii), and the Northern root-knot nematode (Meloidogyne hapla).

Insecticidal and Behavioral Effect of Microparticles of Pimpinella anisum Essential Oil on Larvae of Leptinotarsa decemlineata (Coleoptera: Chrysomelidae).

The Colorado potato beetle ranks as one of the most important potato pests, mainly due to its high feeding rate during all developmental stages, particularly third and fourth larval instar, and high fecundity. The effect of essential oil (EO) from anise (Pimpinella anisum L. [Apiales: Apiaceae]) prepared as conventional and encapsulated (EN) formulations on the mortality and antifeedant responses of young larvae of Colorado potato beetles was studied to evaluate the insecticidal and antifeedant effects of five concentrations of this EO and to assess the persistence of both formulations on potato plants. The EN formulation had a significantly higher residual amount compared with that of the conventionally formulated EO. Significantly different values of LC50 and LC90 (ppm) were established for the EO (LC50 = 1,700 and LC90 = 9500) and EN (LC50 = 3,100 and LC90 = 14,300) formulations. The effects of both P. anisum formulations (EO and EN) applied topically to Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) larvae were distinctly different from those observed with the contact treatment. At the highest concentration of 20,000 ppm, the mortality of the second instars of the L. decemlineata larvae did not exceed 25%. On the other hand, both tested formulations of P. anisum were highly effective when administered orally. The encapsulated EO formulation achieved a distinctly higher biological activity. Our results confirm that the EO from P. anisum, especially the encapsulated formulation, has high insecticidal properties that may lead to the development of new organic products for the control of Colorado potato beetles.