Abstract Detail

Ecology

Leathers, Jack [1], Holcombe, Jaden [2], Manning, Sakura [2], Borer, Catherine [3].

Foliar calcium partitioning and sequestration in herbaceous plants and vines.

Calcium is an essential macronutrient, which helps to stabilize the structure of cell walls and plasma membranes, and serves as a second messenger that elicits appropriate physiological responses to numerous internal and external environmental cues. In order to maintain the low cytoplasmic calcium concentration that allows these processes to occur, cells typically pump calcium into organelles or out into the apoplast. Many plant species also crystalize a substantial fraction of their foliar calcium in a physiologically unavailable form, often as calcium oxalate. This leaves only a small portion of foliar calcium available for critical processes such as signal transduction. Thus, the traditional analysis of total foliar calcium can substantially overestimate the true physiological calcium status of plants. However, evaluating calcium partitioning via sequential foliar extractions has allowed us to understand and compare physiologically relevant pools of calcium, which are not revealed by total foliar analyses.           In previous work, measurement of foliar calcium partitioning has allowed us to explain mechanisms by which Cornus florida enhances ecosystem-level calcium cycling, and it has also allowed us to explain physiological strategies plants can use in order to withstand extremely high-calcium environments. The majority of this previous research has focused on trees and shrubs, but to our knowledge, foliar calcium partitioning has not previously been evaluated in herbaceous plants or vines. In this study, we evaluated foliar calcium partitioning in a range of understory trees, shrubs, vines, and herbaceous plants that are commonly found on the campus of Berry College in northwest Georgia, USA. We used sequential acidic extractions followed by a colorimetric analysis of solutions to evaluate and compare strategies for partitioning and sequestration, limiting, or eliminating excess foliar calcium. We found that species displayed a range of calcium management strategies, with some species that retain a very high proportion of their foliar calcium in labile forms, and other species that chemically sequester nearly all of their foliar calcium. This demonstrates varied calcium management strategies among the species that we studied.

1 - Berry College, Biology, P.O. Box 490430, Mount Berry, GA, 30149, USA
2 - Berry College, Biology, P.O. Box 490430, Mount Berry, GA, 30149, USA
3 - Berry College, Biology, P.O. Box 490430, Mount Berry, GA, 30149, United States

Keywords:
Calcium cycling
Mineral nutrition
Plant Nutrient
Nutrient cycling
herbaceous plants
vines.

Presentation Type: Poster
Session: P1, Ecology Posters
Location: Virtual/Virtual
Date: Monday, July 19th, 2021
Time: 5:00 PM(EDT)
Number: P1EC016
Abstract ID:920
Candidate for Awards:Phytochemical Best Poster Award