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Imaging densitometry of honeydew samples with Densitometric Research Operating Program (DROP)

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The amount of excreta from sap-feeding insects is linked to the differences in ingestion volumes, and it provides valuable information such as the presence of feeding stimulants and deterrents in their diets. In this work, we introduce a newly developed program source code named DROP and use it to produce imaging densitometric analyses of the insect excreta. Our method is straightforward, rapid, has high sensitivity, and is sufficiently accurate, and therefore is applicable to many sap-feeding insects. The DROP and the sample images are freely available on the website https://sites.google.com/view/tsuchida-lab-drop.

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We thank T. Ichishi, N. Murakami, K. Tanaka, M. Yoshizaki for their technical assistance; N. Haruyama for the whitefly samples; T. Fukatsu for the useful comments. This study was supported by grants from the Project of the NARO Bio-oriented Technology Research Advancement Institution (Research Program on development of innovative technology). A. F. was supported by the Leading Initiative for Excellent Young Researchers (LEADER) Program.

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Correspondence to Tsutomu Tsuchida.

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Tsuchida, T., Wasano, N., Wang, Y. et al. Imaging densitometry of honeydew samples with Densitometric Research Operating Program (DROP). Appl Entomol Zool (2020). https://doi.org/10.1007/s13355-020-00672-z

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  • Densitometry
  • Honeydew
  • Aphid
  • Whitefly
  • Image analysis