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Nilai Taksonomi Ciri Anatomi Daun Coelostegia Benth. dan Ceiba pentandra Gaertn. (Bombacaceae)

Sains Malaysiana (Impact Factor: 0.48). 10/2010; 39(3(2010)):371–376.

ABSTRACT Kajian anatomi perbandingan daun dilakukan ke atas tiga spesies daripada genus Coelostegia (C. griffithii, C. borneensis dan C. chartacea) dan juga Ceiba pentandra Gaertn. (Bombacaceae) sebagai spesies perbandingan dalam famili yang sama. Kajian yang dilakukan melibatkan keratan rentas lamina dan tepi daun menggunakan mikrotom gelongsor. Penjernihan daun dilakukan menggunakan larutan 1% Basic Fuchsin di dalam 10% KOH. Hasil kajian menunjukkan ciri sepunya semua spesies Coelostegia yang dikaji iaitu kehadiran sel lendir, jenis trikom, jenis dan taburan hablur, kehadiran sel sklerenkima dan jenis peruratan tengah lamina. Ciri unik yang dikongsi oleh semua spesies genus Coelostegia ialah kehadiran satu hablur tunggal di atas berkas vaskular lamina yang menyambungkannya ke bahagian adaksial epidermis dan seakan-akan membentuk tiang serabut. Manakala variasi interspesies dalam Coelostegia yang boleh digunakan untuk membezakan spesies dalam genus ini ialah bentuk luaran tepi daun, peruratan tepi daun dan taburan trikom. Dalam kajian ini, terdapat tujuh ciri yang boleh membezakan antara Coelostegia dan Ceiba pentandra. Ciri tersebut adalah kehadiran trakeid membengkak yang dapat dilihat pada peruratan lamina, corak berkas vaskular pada tulang daun dan petiol, kehadiran dan jenis hablur, kehadiran dan jenis trikom, sel lendir, sklerenkima pada lamina, hipodermis, sklerenkima pada berkas vaskular petiol dan kehadiran kolenkima. Kajian ini membuktikan bahawa gabungan beberapa ciri anatomi daun mempunyai nilai taksonomi yang boleh digunakan untuk membezakan spesies.

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Available from: Noraini Talip, Jun 10, 2015
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