Abstract Detail

Physiology

Millard, Avery [1], Carver, Michelle [1], Dunn, Michael [1], Smith, Jessica [1], Borer, Catherine [1].

Evaluation of crystalline calcium in dried foliage samples.

Calcium is an essential plant macronutrient, important as a structural component of cell walls and membranes, and as a second messenger to initiate physiological responses to a range of environmental signals. To allow for these functions, calcium must be maintained at low cytoplasmic concentrations, and is commonly pumped into organelles or into the apoplast. Plants can also crystallize excess foliar calcium in a physiologically unavailable form, such as calcium oxalate. In previous work, we have evaluated physiologically relevant pools of foliar calcium using sequential acidic extractions of dried plant foliage. The purpose of this study was to adapt a method that is used to analyze crystalline calcium in fresh plant foliage, and determine whether it may also be used to assess crystallized calcium in dried plant tissues. We used this method to more directly evaluate the physical form of chemically sequestered foliar calcium, and its role in calcium tolerance of plants growing at sites with high calcium availability, such as the gypsum soils at White Sands National Monument in New Mexico. Freeze dried and ground foliage samples were treated to release crystalline calcium, and samples were evaluated via differential interference contrast microscopy. Samples were separated into three groups, based on their relative amounts of chemically sequestered foliar calcium, as determined in a previous study. We found that the relative abundance of crystals, determined via microscopy, was consistent with species groupings of chemically sequestered calcium reported in the previous study. This comparatively simple visual method provides a reasonable estimate of the relative abundance of crystalized calcium in freeze-dried foliage samples, and helps elucidate physiological strategies of tolerance utilized by plants growing at a high calcium site.

1 - Berry College, Biology, P.O. Box 490430, Mount Berry, GA, 30149, USA

Keywords:
Calcium
microscopy
Calcium crystals
Gypsum soils.

Presentation Type: Poster
Session: P, Physiological Posters
Location: Exhibit Hall/Savannah International Trade and Convention Center
Date: Monday, August 1st, 2016
Time: 5:30 PM This poster will be presented at 5:30 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: PPS003
Abstract ID:582
Candidate for Awards:Physiological Section Best poster presentation,Physiological Section Physiological Section Li-COR Prize