Abstract

Whitefly (Aleurotrachelus socialisBondar) is a major pest causing significant eco-nomic losses in cassava production systems in North South America. It diminishescassava’s photosynthesis by colonizing leaves, directly feeding on phloem sap, orexcreting substances that foster sooty mold growth, reducing the photosynthetic area.The most effective pest management approach is deploying natural resistance in thecrop. Identifying germplasm with superior whitefly-resistance (WFR) through phe-notypic evaluation distinguishing it from whitefly-susceptible responses requires anaccurate, high-throughput, quantitative phenotyping method. We developed Nymph-star, an image-based phenotyping tool, as an ImageJ plugin, quantifying third- andfourth-instar nymphs and their leaf area they occupy through red, green, and bluecolor space analysis. Using Nymphstar, we tested 19 cassava genotypes and classifiedtheir resistance toA. socialis. The plugin proved efficient, completing the analysisin 25.56 min on average for the entire dataset. In contrast, manual counting for thesame set of images took 425.23 min on average averaging around 6.29 min/image. Nymphstar was∼17 times faster showcasing its efficiency. To assess WFR in cas-sava germplasm, we conducted a full-bench caging free-choice assay. This approachenhanced whitefly colonization on each cassava genotype, providing an accurate rep-resentation of resistance/susceptible while reducing operator bias. Nymphstar is arapid, precise tool for automated nymphs counting and leaf area quantification. Itfacilitates the large-scale assessment of cassava resistance to whitefly, eliminatingbias associated with field assessment and manual countin

Published in

The Plant Phenome Journal
2023, Volume: 6, number: 1, article number: e20089

SLU Authors

• Leiva, Fernanda

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Plant Protection Network


UKÄ Subject classification

Agricultural Science


Publication identifier

DOI: https://doi.org/10.1002/ppj2.20089

Permanent link to this page (URI)

https://res.slu.se/id/publ/128309