Cahaya matahari diduga berperan dalam proses pembentukan kristal CaOx pada tanaman porang. Penelitian ini bertujuan untuk mengetahui variasi bentuk kristal CaOx dan pengaruh naungan terhadap kerapatan kristal CaOx pada tanaman porang. Preparat untuk pengamatan mikroskopis berasal dari

Sunlight was suspected to affect CaOx crystal formation in porang. This research had aim to determine variations in forms of CaOx crystals and the influence of shade on the density of CaOx crystals in porang. Preparations for microscopic observation derived from sliced leaf, petiole, and tuber of porang that grown under shaded and exposed to sunlight conditions. Sliced organ were cleared by using the modified clearing method. The parameters that observed included shape, shape variety, and density of CaOx crystals. CaOx crystal density were analyzed using ANOVA followed by Tukey (α 0,05). The differences of crystal density between the edges and middle of the organ were analyzed using Paired Samples T Test. Microscopic observation showed that CaOx crystals were grouped into large (20-710 m) and small (1-15 m) crystals size. The density of CaOx crystals in plants exposed to sunlight was 3 times higher than the shaded plants. Leaf organ had the highest number of crystal compared to others organ. The tuber had the lowest density of CaOx crystals among organ. In addition, the shaded or exposed to sunlight condition had no effect on CaOx crystal density between the edges and center of the organ. Key word: Porang, Shade, CaOx crystals, Density of crystals, Variation shape of crystals.

[1]  G. Savage,et al.  Oxalate content of purslane leaves and the effect of combining them with yoghurt or coconut products , 2009 .

[2]  M. S. Khan.  Engineering photorespiration in chloroplasts: a novel strategy for increasing biomass production. , 2007, Trends in biotechnology.

[3]  M. Ku,et al.  Correlations between Calcium Oxalate Crystals and Photosynthetic Activities in Palisade Cells of Shadeadapted Peperomia glabella , 2007 .

[4]  K. Korth,et al.  Medicago truncatula Mutants Demonstrate the Role of Plant Calcium Oxalate Crystals as an Effective Defense against Chewing Insects1 , 2006, Plant Physiology.

[5]  Xinxiang Peng,et al.  Oxalate Accumulation as Regulated by Nitrogen Forms and Its Relationship to Photosynthesis in Rice (Oryza sativa L.) , 2005 .

[6]  V. Franceschi,et al.  Calcium oxalate in plants: formation and function. , 2005, Annual review of plant biology.

[7]  H. Horner,et al.  Calcium Oxalate Crystals in Developing Seeds of Soybean , 2001 .

[8]  P. Rudall,et al.  Calcium Oxalate Crystals in Monocotyledons: A Review of their Structure and Systematics , 1999 .

[9]  M. A. Webb.  Cell-Mediated Crystallization of Calcium Oxalate in Plants , 1999, Plant Cell.

[10]  H. Horner,et al.  Quantitative determination of calcium oxalate and oxalate in developing seeds of soybean (Leguminosae). , 1997, American journal of botany.

[11]  B. Libert,et al.  Oxalate in crop plants , 1987 .

[12]  Y. Lindqvist,et al.  Structure of glycolate oxidase from spinach. , 1984, Proceedings of the National Academy of Sciences of the United States of America.

[13]  R. C. Jones,et al.  Raphides with Barbs and Grooves in Xanthosoma sagittifolium (Araceae) , 1972, Science.

[14]  S. Sen,et al.  The photosynthetic production of oxalic acid in Oxalis corniculata , 1970 .

[15]  T. Kisaki,et al.  Glycolate and glyoxylate metabolism by isolated peroxisomes or chloroplasts. , 1969, Plant physiology.