DOI: 10.5061/dryad.c866t1gc2
title: The data of 960 stomata from four Magnoliaceae species

description: This dataset provides the boundary coordinate data of 960 stomata and the
 fitted results (including the estimated values of model parameters and the
 goodness of fit) using the superellipse and Gielis equations from the four
 Magnoliaceae species with 240 stomata for each species.
description: The following contents were
 cited from Li et al. (2023): Leaf
 sampling  Healthy fully-expanded
 mature leaves of four Magnoliaceae species [(<em>Magnolia
 denudata</em> Desr.<em>, Magnolia stellata</em> (Siebold
 & Zucc.) Maxim., <em>Michelia chapensis</em>
 <em>Dandy.</em>, and <em>Michelia martini </em>(H.
 Lév.) Finet & Gagnep. ex H. Lév]<em> </em>were
 collected between July and August 2022. Forty leaves were selected from
 each species. <em>Magnolia
 denudata</em>,
 <em>M. chapensis</em>, and <em>M. martini</em>
 were collected from the Nanjing Forestry University campus in Nanjing
 (32°4'41''N,
 118°48'34''E), and <em>M. stellata</em> was
 collected from Nanjing
 Botanical Garden Mem. Sun
 Yat-Sen (32°3'17''N,
 118°49'51''E). For convenience, we will refer to these species as Md, Mc, Mm,
 and Ms hereinafter. Lamina
 section sampling and data acquisition For each leaf, two lamina
 sections of approximately 0.5 cm × 0.5 cm were selected along the width
 axis of the leaf, one near the midrib and another section near the leaf
 left margin, respectively. Stomatal images (with a view-field area of 662
 μm × 444 μm for each lamina section) were acquired by the segregation
 method (Jiao et al. 2021). An optical microscope (NE-620; Nanjing Yongxin
 Optics Co., Ltd, Nanjing, China) and ImageView software (version
 4.11.17864; Shanghai Pooher Electro-Optical Co., Ltd, Shanghai,
 China) installed on a desktop Lenovo XiaoXinAir 15ITL 2021 computer
 (Lenovo Group Limited, China) were used to observe and capture images.
 Taking care to avoid major leaf veins during photographing, the exported
 images were saved as TIF files at 72 ppi resolution totally having 5440 ×
 3648 pixels (with actual size of 662 μm × 444
 μm). For each of the four
 Magnoliaceae species, 240 stomata were randomly selected from the images
 taken, resulting in a total of 960 stomata. The boundary of each stoma
 selected was manually redrawn using the Procreate software (version 5.2.9;
 Savage Interactive Pty Ltd, Hobart, TAS, Australia) on an iPad air3
 (version 14.7.1; Adobe Systems Incorporated, Cupertino, CA, USA). First,
 the lamina section TIF
 files were imported into the Procreate software; second, a new layer was
 created for redrawing the boundary of a stoma randomly sampled; third, the
 studio brush in Procreate was selected, and the opacity of the studio
 brush was adjusted to be maximum; fourth, a stoma was randomly selected,
 and its boundary was redrawn using the studio brush on the newly built
 layer; fifth, the inside of the redrawn stomatal boundary was filled with
 black; sixth, the output files were saved in PSD
 format; seventh, the
 stomatal images were then cropped and converted to black and white BMP
 images using Adobe Photoshop 2021 (version 22.4.2; Adobe Systems
 Incorporated, San Jose, CA, USA); finally, the planar coordinates of the
 stomatal profile (i.e., the planar projection of the stoma) in the
 Cartesian coordinate system were extracted using a MATLAB program (Shi et
 al. 2018; Su et al. 2019 for details). The number of approximately
 equidistant data points
 forming, each stomatal perimeter was fixed at 500. To reduce the
 measurement error, two female graduate students with similar age (i.e., QL
 and LZ in the list of authors, who were 24 and 22 years old and came from
 the same province) were arranged to carry out the above operating
 procedures. Before formally carrying out the redrawing work, they were
 trained to perform the above operating procedures in the same manner as a
 pre-experiment. References 
 Jiao Y, Gao Z, Wang R. 2021. Application of
 segregation process in observing the leaf stomatal structure of
 <em>Michelia</em> plants. Anhui For Sci Technol. 47(1):26–29.
 doi: 10.3969/j.2095-0152.2021.01.009. 
 Li Q, Niklas KJ, Niinennets Ü, Zhang L,
 Yu K, Gielis J, Gao J and Shi P. 2023. Stomatal shape described by a
 superellipse in four Magnoliaceae species. Bot Lett.
 In
 press.
 https://doi.org/10.1080/23818107.2023.2234443 
 Shi P, Gielis J, Quinn BK, Niklas KJ, Ratkowsky
 DA, Schrader J, Ruan H, Wang L and Niinennets Ü. 2022.
 'biogeom': An R package for simulating and fitting natural
 shapes. Ann NY Acad Sci 1516:123-134. doi:
 10.1111/nyas.14862. Shi P, Ratkowsky DA, Li Y, Zhang L, Lin S,
 Gielis J. 2018. A general leaf area geometric formula exists for
 plants—evidence from the simplified gielis equation. Forests.
 9(11):714. doi:
 10.3390/f9110714. Su J, Niklas KJ, Huang W, Yu X, Yang Y, Shi P.
 2019. Lamina shape does not correlate with lamina surface area: an
 analysis based on the simplified Gielis equation. Glob Ecol Conserv.
 19:e00666. doi: 10.1016/j.gecco.2019.e00666.