Establishing an inexpensive, space efficient colony of Bemisia tabaci MEAM1 utilizing modelling and feedback control principles

J Appl Entomol. 2022 Jun;146(5):648-658. doi: 10.1111/jen.12995. Epub 2022 Mar 24.

Abstract

A stable, synchronized colony of whitefly (Bemisia tabaci MEAM1 Gennadius) was established in a single ~30 cu.ft. reach-in incubator and supported on cabbage host plants which were grown in a 2 × 2' mesh cage without the need for a greenhouse or dedicated growth rooms. The colony maintenance, including cage cleaning and rotation of plants, was reduced to less than 10 h per week and executed by minimally experienced researchers. In our hands, this method was approximately 10-fold less expensive in personnel and materials than current typical implementations. A predator-prey model of whitefly colony maintenance that included whitefly proliferation and host plant health was developed to better understand and avoid colony collapse. This quantitative model can be applied to inform decisions such as inoculum planning and is a mathematical framework to assess insect control strategies. Extensive measurements of colony input and output (such as image analysis of leaf area and whitefly population size) were performed to define basic 'feedback control' parameters to gain reproducibility of this inherently unstable scaled-down whitefly colony. Quantitative transfer of ~100 whiteflies repeatedly produced more than 5000 adult whiteflies over a 6-week, two-generation period. Larger scale experimentation could be easily accommodated by transferring adult whiteflies from the maintenance colony with a low flow vacuum capture device. This approach to colony maintenance would be useful to programs that lack extensive plant growth room or greenhouse access and require a "clean" implementation that will not contaminate an axenic tissue culture laboratory.

Keywords: cost reduction; crop protection; image analysis; insectary; proliferation kinetics; quality control; whitefly.