Pengaruh Pemberian Kalsium Terhadap Ukuran dan Kerapatan Kristal Kalsium Oksalat pada Porang (Amorphophallus muelleri blume) - Nunung Harijati; Estri Laras Arumingtyas; Rian Handayani (Indonesian Journal of Environment and Sustainable Development, 2010)
Abstrak Porang (Amorphophallus muelleri Blume) mempunyai ciri famili Araceae yaitu mempunyai kristal calcium oxalate. Porang direkomendasikan di tanam di bawah tegakan kayu Jati, kayu jati berkualitas umumnya hidup pada daerah kapur. Disamping sebagai tanaman yang bernilai kesehatan tinggi karena kandungan glukomanannya, Porang mempunyai sisi lemah dari sisi kesehatan yaitu mengandung kristal Ca-oksalat. Untuk itu perlu diteliti apakah lingkungan berkapur mempengaruhi ukuran dan kerapatan kristal kalsium oxalate dari Porang. Dengan menggunakan disain penelitian Rancangan Acak Lengkap, 4 dosis kapur (Dolomit) yaitu 2 g, 4 g, 8 g, dan 16 g tiap kg tanah diberikan ke Porang  dan kontrol (tanpa diberi kapur). Hasil penelitian menunjukkan bahwa ukuran kristal rafida semakin meningkat selaras dengan peningkatan kapur. Tetapi, peningkatan dosis dolomit pada kristal druse tidak menambah ukuran diameter, namun menambah jumlah per satuan luas. Ukuran tertinggi (359,6 µm) kristal rafida dihasilkan dari dosis 16 g tiap kg. Dari pengukuran kerapatan kristal setiap mm2, didapatkan kristal lebih rapat pada daun dibandingkan tangkai daun. Kerapatan kristal meningkat selaras dengan kenaikan dosis pemberian dolomit. Kerapatan tertinggi diperoleh dari dosis pemupukan 16 g tiap kg tanah yaitu sebesar 838 kristal tiap mm2 untuk daun. Berdasarkan jumlah tersebut, proporsi kristal druse lebih tinggi (686 kristal tiap mm2) dibandingkan kristal rafida (147 kristal tiap mm2). Penambahan kapur, berpengaruh terhadap penambahan ukuran kristal rafida sedangkan untuk kristal druse mengalahi penambahan  jumlah kristal. Kata kunci : dolomit, druse, jumlah Kristal, rafida, ukuran kristal Abstract Porang (Amorphophallus muelleri Blume) have a characteristic family Araceae that have calcium oxalate crystals. Porang was recommended planting under teak tree. And generally high quality of teak wooden are obtained from teak trees that are grown in calcareous soils.  Beside as a high health-value crops because the content of its glucomannan, Porang also contained Ca-oxalate as a weak side. Therefore it was needed to study whether calcareous environment affected the size and density of calcium oxalate in Porang. The experiment was designed using completely randomized design with 4 doses of lime (dolomite), namely 2g/kg, 4 g / kg, 8g/kg, 16g/kg soil and 0g/kg as a control. The results showed that the crystal raphide size increased in line with the increase of lime dose. However, Increased dolomite dosage did not increase the size of diameter crystals-druse but increased the number  per unit area. Highest size (372 µm) of raphide crystals were generated from 16g/kg dose. From the measurement of crystal density per mm2, more dense crystals obtained  in the leaves than the petiole of Porang. Crystal density increased in line with dose increase of dolomite. The highest density of crystal was obtained from 16g/kg soil fertilization dose i.e. 838 kristal/mm2 in the leaf. Of these, Druse crystal proportion was higher than crystal rafida i.e. 686 crystal /mm2 and 147 crystal /mm2 for druse and raphide respectively. The addition of lime, for crystal rafida had effect by increase the size of crystals, while for crystals Druse by increasing the number of crystals. Keywords: Dolomite, raphide, Druse, crystal size, number crystal