Polycrystalline calcium oxalate in a May Apple
The tissue making up the interior bulk of the gynoexium wall of this May Apple shows may clusters of crystalline material as evidenced by birefringence observed under crossed polarizers (bright yellow features). This is calcium oxalate. With a lambda wave plate, the isotropic material is purple. The specimen was stained with Hematoxylin resulting in the very dark nuclei. This is a longitudinal cross section of the gynoecium from a May Apple ( Podophyllum sp.) Specimen from the edge of the Dowagiac River (5/15).
The crystalline morphology of and distribution of the calcium oxalate varies with plant species. For example, in Wild Ginger, I have found it to consist of single crystals as opposed the polycrystalline aggregates here. In addition, in the Wild Ginger, it is found primarily in the cell placental wall, where as here it is in the bulk and not the wall.
The protocol was as follows. Specimens fixed in FAA (formaldehyde, acetic acid, ethanol) 48 hr. Dehydrated in 35, 50, 75, 85, 95, 99 % IPA in water, 6 hours each min. Infiltrated in xylene saturated with Paraplast for 2 days, followed by 2 changes of melted Praplast for 2 hours each. Embedded in Paraplast. Sectioned on a Spencer 820 microtome at 11 micron. Cleared in Xylene 2X, 10 min each. Rehydrated 99 (10 min), 95, 85, 70 % IPA, 2 min. each. Stained Gill's Hematoxylin 10 sec. Washed 3 min running water. Blued 0.05 % lithium carbonate 3 s. Water rinse 1 min. Stained 1 % aq. Erythrosin-B 2 min. Dehydrated 99 % IPA 2 min. Cleared 2X xyene 5 min each. Mounted with DEPEX.
Photographed on a Spencer 42 petrographic polarizing microscope with crossed polarizers and a Lambda wave plate using an original magnification of 430X, using a Sony NEX 5N with a Leica MIKAS 1/3X adapter.
Polycrystalline calcium oxalate in a May Apple
The tissue making up the interior bulk of the gynoexium wall of this May Apple shows may clusters of crystalline material as evidenced by birefringence observed under crossed polarizers (bright yellow features). This is calcium oxalate. With a lambda wave plate, the isotropic material is purple. The specimen was stained with Hematoxylin resulting in the very dark nuclei. This is a longitudinal cross section of the gynoecium from a May Apple ( Podophyllum sp.) Specimen from the edge of the Dowagiac River (5/15).
The crystalline morphology of and distribution of the calcium oxalate varies with plant species. For example, in Wild Ginger, I have found it to consist of single crystals as opposed the polycrystalline aggregates here. In addition, in the Wild Ginger, it is found primarily in the cell placental wall, where as here it is in the bulk and not the wall.
The protocol was as follows. Specimens fixed in FAA (formaldehyde, acetic acid, ethanol) 48 hr. Dehydrated in 35, 50, 75, 85, 95, 99 % IPA in water, 6 hours each min. Infiltrated in xylene saturated with Paraplast for 2 days, followed by 2 changes of melted Praplast for 2 hours each. Embedded in Paraplast. Sectioned on a Spencer 820 microtome at 11 micron. Cleared in Xylene 2X, 10 min each. Rehydrated 99 (10 min), 95, 85, 70 % IPA, 2 min. each. Stained Gill's Hematoxylin 10 sec. Washed 3 min running water. Blued 0.05 % lithium carbonate 3 s. Water rinse 1 min. Stained 1 % aq. Erythrosin-B 2 min. Dehydrated 99 % IPA 2 min. Cleared 2X xyene 5 min each. Mounted with DEPEX.
Photographed on a Spencer 42 petrographic polarizing microscope with crossed polarizers and a Lambda wave plate using an original magnification of 430X, using a Sony NEX 5N with a Leica MIKAS 1/3X adapter.