Morpho-anatomy of marijuana (Cannabis sativa L.)

Abstract

Cannabis sativa is a complex species with highly variable morphological features. The present chapter provides detailed descriptions of morphological and anatomical characters of various parts of C. Sativa plant and illustrated with bright-field and scanning electron micrographs. Male and female flowers occur in separate plants. Three types of glandular trichomes namely, glandular stalked, glandular sessile and bulbous glandular trichomes are found. Of these, glandular stalked trichomes are restricted to the floral bracts in pistillate plants and anthers in staminate plants. The other two types of glandular trichomes are found in various parts including bracts, leaves, stems and petioles. Two types of non-glandular trichomes namely, cystolith trichomes and slender covering trichomes, are present. Cystolith trichomes are primarily found on the adaxial leaf surface while the covering trichomes are commonly present on the abaxial leaf surface, stems, petioles and tepals. Cystolith crystals of calcium carbonate and cluster crystals of calcium oxalate are observed in the leaves. Anatomical features of various parts of the plant are described and illustrated.