Effects of several UV-protective substances on the persistence of the insecticidal activity of the Alphabaculovirus of Chrysodeixis chalcites (ChchNPV-TF1) on banana (Musa acuminata, Musaceae, Colla) under laboratory and open-field conditions

PLoS One. 2021 May 12;16(5):e0250217. doi: 10.1371/journal.pone.0250217. eCollection 2021.

Abstract

Alphabaculovirus of Chrysodeixis chalcites (ChchNPV-TF1) has been investigated as a useful bioinsecticide against C. chalcites (Esper) (Lepidoptera: Noctuidae) in banana crops. This study investigated the effects of several substances on the persistence of ChchNPV-TF1 under field conditions in the Canary Islands. Natural photoprotective substances, such as moringa, cacao, green tea, benzopurpurine, charcoal, iron dioxide, benzimidazole, kaolinite, and bentonite, were first evaluated under laboratory conditions using a Crosslinker as UV light source at 200 J/cm2. The photoprotective substances were divided into three groups: low protection (0-8%; kaolinite), intermediate protection (48-62%; green tea, moringa, bentonite and cacao) and high protection (87-100%; charcoal, iron ioxide). Benzopurpurine and benzimidazole did not provide any photoprotective effects. Two of the substances that yielded the best results, 1% cacao and 1% charcoal, were selected for the open-field experiment in a banana plantation. The persistence of ChchNPV-TF1 OBs (occlusion bodies) on leaf surfaces with sunlight exposure was analysed by comparing the initial mortality of 2nd instar C. chalcites larvae with the mortality observed at various intervals postapplication. The mortality rates decreased over time in all treatments and were always higher in the UV-protective substance-treated parcels. The 1% charcoal treatment exhibited the highest protection in both the laboratory and field experiments. No specific interference of UV-protective substances on the maximum photochemical efficiency of banana plants was observed under field conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bentonite / pharmacology
  • Benzimidazoles / pharmacology
  • Cacao / chemistry
  • Charcoal / pharmacology
  • Insecticides / pharmacology*
  • Kaolin / pharmacology
  • Lepidoptera / virology
  • Moringa / chemistry
  • Nucleopolyhedroviruses / drug effects
  • Nucleopolyhedroviruses / radiation effects
  • Spain
  • Tea / chemistry
  • Ultraviolet Rays*

Substances

  • Benzimidazoles
  • Insecticides
  • Tea
  • Bentonite
  • Charcoal
  • Kaolin
  • benzimidazole

Grants and funding

This research was supported by Ministerio de Economía y Competitividad-INIA, España - CCAA (2014-2017), project title “El Alphabaculovirus de Chrysodeixis chalcites un nuevo agente de control biológico: su integración en programas de Gestión Integrada de Plagas (GIP)” ("Chrysodeixis chalcites Alphabaculovirus a new biological control agent: its integration in Integrated Pest Mangement (IPM) programs”) (RTA2013-00114-C02) in the form of a grant awarded to ICIA and IMAB, and Ministerio de Ciencia e Innovación, España - Subvenciones para la formación de personal investigador en agroalimentación en los centros de investigación agraria y alimentaria INIA-CCAA FPI INIA) (https://www.ciencia.gob.es/portal/site/MICINN/menuitem.dbc68b34d11ccbd5d52ffeb801432ea0/?vgnextoid=792df5b222132710VgnVCM1000001d04140aRCRD) in the form of a grant awarded to TC (CPD 2015-0205). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.