Sains Malaysiana 29: 45-62 (2000)                                                                                                                Sains Hayat /

Life Sciences

The Significance of Leaf Morphological Characters for the

Identificationof Carica papaya L. cultivars in Malaysia

Chan Lai Keng & Chris K.H. Teo

School of Biological Sciences

Universiti Sains Malaysia

11800 Pulau Pinang, Malaysia

ABSTRACT

The detailed study of the papaya leaves morphology indicated that there were significant differences in the macrostructures and microstructures of the leaves between the 22 papaya cultivars that were grown in Malaysia. The number of leaf main veins, number of lobes at the leaf margin, leaf shape, type of stomata and wax structures on the leaf surface, and the colour of leaf petiole were the important characters used for the identification of the papaya cultivars. This information enabled us to identify the 22 papaya cultivars grown in Malaysia with a proposed taxonomic key.

ABSTRAK

Kajian terperinci tentang morfologi daun betik telah menunjukkan bahawa struktur makro dan mikro daun adalah berbeza secara bererti di antara 22 kultivar betik yang ditanam di Malaysia. Bilangan urat daun, bilangan cuping di tepi lamina daun, bentuk daun, jenis stomata dan struktur lilin yang terdapat di permukaan daun, dan warna petiol daun adalah ciri-ciri yang penting untuk pencaman kultivar betik. Dengan makluman ini, satu kunci taksonomi dicadangkan untuk mengcamkan 22 kultivar betik yang terdapat di Malaysia.

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