Increasing the survival and efficacy of entomopathogenic nematodes on exposed surfaces by Pickering emulsion formulations offers new venue for foliar pest management

Jayashree Ramakrishnan; Liora Salame; Karthik Ananth Mani; Reut Feldbaum; Eldad Karavani; Guy Mechrez; Itamar Glazer; Dana Ment

doi:10.1016/j.jip.2023.107938

Increasing the survival and efficacy of entomopathogenic nematodes on exposed surfaces by Pickering emulsion formulations offers new venue for foliar pest management

J Invertebr Pathol. 2023 Jul:199:107938. doi: 10.1016/j.jip.2023.107938. Epub 2023 Jun 1.

Authors

Jayashree Ramakrishnan¹, Liora Salame², Karthik Ananth Mani³, Reut Feldbaum⁴, Eldad Karavani⁵, Guy Mechrez⁴, Itamar Glazer⁶, Dana Ment⁷

Affiliations

¹ Department of Plant Pathology and Weed Research, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel; Department of Agroecology and Plant Health, The Robert H. Smith Faculty of Agriculture, Food & Environment the Hebrew University of Jerusalem, Rehovot 7610001, Israel.
² Department of Plant Pathology and Weed Research, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel.
³ Department of Food Science, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel; Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel.
⁴ Department of Food Science, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel.
⁵ Department of Vegetable Research, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel.
⁶ Department of Entomology, Nematology and Chemistry Units, Agricultural Research Organization, Volcani Institute, Rishon LeZion 7505101, Israel.
⁷ Department of Plant Pathology and Weed Research, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel. Electronic address: danam@volcani.agri.gov.il.

PMID: 37268287
DOI: 10.1016/j.jip.2023.107938

Abstract

Formulation technology has been the primordial focus to improve the low viability and erratic infectivity of entomopathogenic nematodes (EPNs) for foliar application. Adaptability to the fluctuating environment is a key trait in ensuring the survival and efficacy of EPNs. Hence, tailoring formulations towards EPNs foliar applications would effectively deliver consistent and reliable results for above-ground applications. EPNs survival and activity were characterized in novel Pickering emulsion post-application in planta cotton foliage. Two different types of novel formulations, Titanium Pickering emulsion (TPE) and Silica Pickering emulsion Gel (SPEG), were tailored for EPNs foliar applications. We report an extension of survival and infectivity to 96 hrs under controlled conditions by SPEG formulations for survival of IJ's on cotton foliage. In addition, survival of IJs (LT₅₀) was extended from 14hrs in water to > 80 hrs and > 40 hrs by SPEG and TPE respectively. SPEG accounted for the slowest decrease of live IJs per surface area in comparison to TPE and control samples over time, exhibiting a 6-fold increase at 48 hrs. Under extreme conditions, survival and efficacy were extended for 8hrs in SPEG compared to merely 2hrs in control. Potential implications and possible mechanisms of protection are discussed.

Keywords: Entomopathogenic nematodes; Foliar application; Formulations; Pickering emulsion; Relative humidity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Emulsions / pharmacology
Nematoda*
Pest Control, Biological* / methods

Substances

Emulsions