Mr. Michael GómezMs. Ana Laura Velázquez

Dr. Robert Ross

UPR at CayeyRISE Program

Introduction Mangrove environment

Water with high concentrations of dissolved salts

Morphological adaptations to SaltSalt secretionSequester Salt

BenefitsSecrete excess saltsPrevent water stress

Purpose Observe structure of

salt glands Observe maturation

of leaves

Hypothesis

Young mangrove salt glands morphology is more capable of salt secretion than old mangrove salt glands.

Objectives

Compare the morphology of young and old mangrove salt glands.

Goals

Short term goalsDescribe histological features

of young and mature

mangrove leaves & their salt glands

Long term goalsCompare the normal growth observed in Salinas

to a polluted area exposed to

different chemicals.

Procedures

Obtaining samples Microscopy techniques Paraffin Embedding Sectioning Mounting Staining

Obtaining samplesSalinas, PR

Salina’s Bay

White mangrovesYoung and mature leaves (with glands)

Obtaining samples (cont.)

Petioles with salt glands

Obtaining samples (cont.)

Leaves with salt glands

Microscopy techniquesDisecting scope images

Microscopy techniques (cont.)Epidermal surface (reflected vs. transmitted light)

Reflected light Transmitted light

Microscopy techniques (cont.)Upper epidermis (reflected vs. transmitted light)

Reflected light Transmitted light

Microscopy techniques (cont.)

Upper epidermis Lower epidermis

Microscopy techniques (cont.)

Stomata 200x darkfield

Fixation Dehydration Embedding Blocking Sectioning Mounting Staining

Histological Techniques

ResultsYoung mangrove salt gland

Results (cont.)Young mangrove leaf

Results (cont.)Young mangrove leaf (cross section)

Results (cont.)Young mangrove leaf (cross section)

Results (cont.)Mature mangrove salt gland

Results (cont.)Mature mangrove leaf (cross section)

Results (cont.)Mature mangrove leaf (cross section)

Conclusion Mangrove salt glands in petioles and leaves are

bigger in size in young tissue than in mature tissue.

Glands in young leaves Glands in mature leaves

ReferencesChanita, P., et. al. Salt uptake and shoot water relations in mangroves. Aquatic

Botany 78 (2004) 349-360

Mangroves. 08 Jan. 2008. Marietta College Biology Department. 23 Mar. 2009 http://www/marietta.edu/~biol/biomes/magroves.htm

Ruzin, et. al. 1999. Plant Microtechniques and Microscopy. University of Oxford.

Shua, S., et. al. Molecular phylogenetic analysis of mangroves: independent evolutionary origins of vivipary and salt secretion. Molecular Phylogenetics and Evolution 34 (2005) 193-205.

Zouhaier, B., et. al. Contribution of NaCl excretion to salt resistance of Aeluropus littoralis (Wild) Parl Molecular. Journal of Plant Physiology 164 (2007) 842-850.

Acknowledgments

Dr. Robert Ross

Dr. Eneida Díaz

Yadira Ortiz

RISE Program