Abstract Detail

Physiology & Ecophysiology

Eckart, Phoebe [1], Alsamadisi, Noah [1], Martin, Celia [2], Spicer, Rachel [3].

Auxin transport affects vessel structure and hydraulic properties in hybrid poplar.

The plant hormone auxin (indole-3-acetic acid; IAA) has a well-established role in the regulation of vascular development, where vascular strands are initiated in cell files containing high concentrations of IAA due to PIN protein-mediated transport. In contrast, little is known about the effects of auxin transport on vessel development specifically. We applied the auxin transport inhibitor NPA in longitudinal strips (lanolin + DMSO + 1% w/v NPA) to stems of 3-month-old Populus tremula x alba and monitored the effects on xylem development and stem hydraulic properties. Interestingly, xylem growth was significantly reduced under both control (lanolin + DMSO) and NPA treatments relative to the untreated stem surface, whereas only the NPA treatment produced abnormally shaped vessels. Vessels formed under NPA were smaller in diameter, more tightly clustered, shorter in length and more angular in cross-section relative to those of controls. Native specific conductivity (k_s, m² s^-1 MPa^-1) was about 20% lower in NPA-treated plants relative to controls and preliminary evidence suggests that this may have been due to increased embolism accumulation. Our results suggest that auxin transport plays a significant role in the differentiation and expansion of vessels with corresponding consequences on stem hydraulic function.

1 - Connecticut College, Botany
2 - Connecticut College, Biology
3 - Connecticut College, Botany, 270 Mohegan Avenue, New London, CT, 06320, USA

Keywords:
auxin
vessel
hybrid poplar
xylem
wood anatomy.

Presentation Type: Poster
Session: P, Physiology & Ecophysiology
Location: Exhibit Hall/Omni Hotel
Date: Monday, June 26th, 2017
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PPE008
Abstract ID:417
Candidate for Awards:None