Electronic Theses and Dissertation

Penelitian ini bertujuan untuk mengkaji struktur morfologi dan anatomi daun c. argentea, c. costata, dan c. cf. hypophoenicea yang berasal dari stasiun penelitian soraya kawasan ekosistem leuser. karakter morfologi yang diamati yaitu bangun daun, ujung daun, pangkal daun, tepi daun, tangkai daun, permukaan atas dan bawah daun, tekstur daun, dan venasi daun. karakter anatomi yang diamati yaitu struktur jaringan helaian daun, tangkai daun, tulang daun, stomata, kristal, dan trikoma. metode kerja pengamatan morfologi dilakukan dengan mengamati langsung karakter yang diamati dan dibandingkan dengan literatur. metode kerja pembuatan preparat anatomi meliputi perebusan, clearing, pewarnaan, dehidrasi, dan mounting. hasil pengamatan morfologi menunjukkan daun c. argentea berbentuk obovate, sedangkan c. costata dan c. cf. hypophoenicea berbentuk elliptical. pangkal daun c. argentea, c. costata, dan c. cf. hypophoenicea berturut-turut adalah acute, obtuse, dan cuneate. ujung daun seluruh jenis castanopsis berbentuk accuminate, tepi daun entire, tangkai daun bulat. tekstur daun c. argentea adalah chartaceous, sedangkan pada c. costata dan c. cf. hypophoenicea adalah coriaceous. seluruh jenis castanopsis memiliki tipe urat daun primer pinnate, tipe urat daun sekunder eucamptodromous, tipe urat daun tersier scalariform, venasi tepi daun tertutup, terdapat free-ending veinlet pada areola. struktur anatomi helaian daun, tulang daun, dan tangkai daun ketiga jenis castanopsis menunjukkan kesamaan dengan tipe stomata siklositik. bentuk kristal oksalat pada c. argentea dan c. cf. hypophoenicea adalah drus dan prismatik, sedangkan pada c. costata adalah drus, raphida, dan pasir. jenis trikoma pada c. argentea antara lain trikoma kelenjar kapitat dan trikoma nonkelenjar stellat serta uniseluler sederhana. trikoma pada c. costata dan c. cf. hypophoenicea adalah trikoma nonkelenjar fasikulat dan uniseluler sederhana. kata kunci: anatomi daun, castanopsis, fagaceae, kawasan ekosistem leuser, morfologi daun

This study aims to examine the morphological and anatomical structure of the leaves of C. argentea, C. costata, and C. cf. hypophoenicea collected from the Soraya Research Station, Leuser Ecosystem. The observed morphological characters included leaf shape, apex, base, margin, petiole, adaxial and abaxial surfaces, leaf texture, and venation pattern. The anatomical characters observed were the tissue structure of the leaf blade, petiole, midrib, stomata, crystals, and trichomes. Morphological observations were carried out through direct examination and comparison with relevant literature. The anatomical preparations involved boiling, clearing, staining, dehydration, and mounting. Morphological observations showed that C. argentea has an obovate leaf shape, while C. costata and C. cf. hypophoenicea have elliptical leaves. The leaf bases of C. argentea, C. costata, and C. cf. hypophoenicea are acute, obtuse, and cuneate, respectively. All three Castanopsis species have acuminate apices, entire margins, and rounded petioles. The leaf texture of C. argentea is chartaceous, while that of C. costata and C. cf. hypophoenicea is coriaceous. All species possess pinnate primary venation, eucamptodromous secondary veins, and scalariform tertiary venation, with closed marginal venation and free-ending veinlets within areoles. Anatomical observations of the leaf blade, midrib, and petiole revealed similar structures across the three species, all exhibiting cyclocytic stomata. The oxalate crystal forms found in C. argentea and C. cf. hypophoenicea were druses and prismatic crystals, while C. costata contained druses, raphides, and sand crystals. Trichome types in C. argentea included capitate glandular trichomes and non-glandular trichomes of the stellate and simple uniseriate types. Meanwhile, C. costata and C. cf. hypophoenicea exhibited non-glandular trichomes of the fasciculate and simple uniseriate types. Keywords: Castanopsis, Fagaceae, leaf anatomy, leaf morphology, Leuser Ecosystem