White Skin Orange Sweet Potato Grown in Limapuluh Kota District, West Sumatra Indonesia: Morphology and Elemental Analysis by Energy-Dispersive X-ray Flourescence

The white skin sweet orange potato (Ipomoea batatas Linn ) was grown by organic method without using any synthetic fertilizer. It was harvested after 4 months of cultivation. Scanning electron photomicrograph of both transversal and longitudinal cross sections showed the formation of starch crystals having round or spherical and polygonal shape with sizes between 2 and 30 μm. Only carbon, oxygen as major elements and small concentration of potassium, calcium and magnesium were detected by energy-dispersive X-ray spectrometry. The absence of some important essential elements demands further investigation on soil-plant nutrient uptake relationship towards the production of highly nutritional potato.