Abstract Detail

Development and Structure

Bullock, Madison [1], Williams, Tanisha [2], Martine, Christopher [3], Haase, Butch [4], Cantley, Jason [1].

Exploring the potential evolutionary adaptation of leaf heteroblasty in Hawaiian Chenopodium oahuense ssp. ilioensis.

The genus Chenopodium L. (Amaranthaceae) is distributed worldwide and includes economically significant species such as quinoa (Chenopodium quinoa), kañiwa (Chenopodium pallidicaule), and lamb’s quarters (Chenopodium album). In Hawai‘i, the sole species, Chenopodium oahuense, generally inhabits a variety of xeric habitats including rocky sea cliffs, sandy beaches, and dry to mesic forests. However, as this taxon is morphologically variable across these habitats, several additional taxa have previously been split from and eventually recombined into a diverse C. oahuense. The Cantley Lab at San Francisco State University recently described a novel subspecies, Chenopodium oahuense subsp. ilioensis, from the northwestern portion of Moloka‘i, which differs from the typical form of C. oahuense by its smaller, succulent leaves, smaller seed size, and prostrate to scandent habit. Moreover, C. oahuense ssp. ilioensis exhibits remarkable leaf heteroblasty when transitioning from juvenile to adult life stages. To further clarify the boundaries between the two subspecies and to characterize the remarkable heteroblastic change to succulence, we conducted landmark, elliptical Fourier descriptor (EFD), and shape descriptor analyses on data obtained from greenhouse plants grown over 28 weeks. Preliminary results show that the separation of subspecies is significantly represented via EFD and shape descriptor analyses. Significant patterns of heteroblastic change, however, are largely due to shape descriptors such as area and thickness alone, and not overall leaf shape.

1 - San Francisco State University, Biology, 1600 Holloway Avenue, San Francisco, CA, 94132, USA
2 - Bucknell University, Biology, 1 Dent Drive, Lewisburg, PA, 17837, United States
3 - Bucknell Univeristy, Biology, 1 Dent Drive, Lewisburg, PA, 17837, USA
4 - Moloka'i Land Trust, PO Box 1884, Kaunakakai, HI, 96748 , USA

Keywords:
Heteroblasty
Chenopodium
Morphometrics
Hawai'i.

Presentation Type: Oral Paper
Session: DS3, Development and Structure III
Location: /
Date: Thursday, July 22nd, 2021
Time: 1:30 PM(EDT)
Number: DS3014
Abstract ID:1080
Candidate for Awards:Katherine Esau Award,Developmental and Structural Section Graduate Student Registration Award