Table 3.

Overview of methods used to generate image data for deep learning analysis of stomata

Data collection type	Method	Paper
Non-destructive	Nail varnish-based surface impressions	Jayakody et al. (2017, 2021), Meeus et al. (2020), Millstead et al. (2020), Bheemanahalli et al. (2021), Costa et al. (2021), Cowling et al. (2021, Preprint), Gibbs et al. (2021), Hunt et al. (2021), Kwong et al. (2021), Razzaq et al. (2021), Ren et al. (2021), Toda et al. (2021), F. Zhang et al. (2022, 2023), Dey et al. (2023), Meng et al. (2023), Pathoumthong et al. (2023), Yang et al. (2024), Wang et al. (2024a)
	Direct microscope imagery	Bhugra et al. (2018), Li et al. (2019), Andayani et al. (2020), Song et al. (2020), Sun et al. (2021, 2023), Yang et al. (2021, 2024), Dai et al. (2022, Preprint), Liang et al. (2022), Sai et al. (2022, Preprint), Pathoumthong et al. (2023), Takagi et al. (2023)
Destructive	Epidermal separation	Casado-García et al. (2020), Aono et al. (2021), Zhu et al. (2021), Li et al. (2022), X. Zhang et al. (2023, Preprint), Yang et al. (2024)
	Use of leaf discs	Toda et al. (2018, Preprint)
	Freezing samples in liquid nitrogen	Bhugra et al. (2019)
	Leaf clearing	Fetter et al. (2019), Sultana et al. (2021)
	Optical topometry	Xie et al. (2021)
	Printing	Sakoda et al. (2019)