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Title: Intra‐leaf modeling of Cannabis leaflet shape produces leaf models that predict genetic and developmental identities
Summary

The iconic, palmately compound leaves ofCannabishave attracted significant attention in the past. However, investigations into the genetic basis of leaf shape or its connections to phytochemical composition have yielded inconclusive results. This is partly due to prominent changes in leaflet number within a single plant during development, which has so far prevented the proper use of common morphometric techniques.

Here, we present a new method that overcomes the challenge of nonhomologous landmarks in palmate, pinnate, and lobed leaves, usingCannabisas an example. We model corresponding pseudo‐landmarks for each leaflet as angle‐radius coordinates and model them as a function of leaflet to create continuous polynomial models, bypassing the problems associated with variable number of leaflets between leaves.

We analyze 341 leaves from 24 individuals from nineCannabisaccessions. Using 3591 pseudo‐landmarks in modeled leaves, we accurately predict accession identity, leaflet number, and relative node number.

Intra‐leaf modeling offers a rapid, cost‐effective means of identifyingCannabisaccessions, making it a valuable tool for future taxonomic studies, cultivar recognition, and possibly chemical content analysis and sex identification, in addition to permitting the morphometric analysis of leaves in any species with variable numbers of leaflets or lobes.

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Award ID(s):
2310355
NSF-PAR ID:
10513274
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
New Phytologist
ISSN:
0028-646X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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