Morphological and Anatomical Characteristics of Cocoa Plants (Theobroma cacao L.) That Grow at Different Heights

Kakao (Theobroma cacao L.) atau dikenal sebagai cokelat merupakan salah satu komoditas unggulan Indonesia yang memiliki keragaman tinggi. Untuk meningkatkan produktivitas kakao diperlukan kultivar unggulan yang sesuai lingkungannya sehingga diperlukan kajian karakter  morfologi dan anatomi. Tujuan penelitian ini mengetahui kultivar unggul ditinjau dari karakter morfologi, ekologi, dan anatomi dan mengetahui keterkaitan antara  karakteristik morfologi dan anatomi tanaman Kakao  yang tumbuh pada ketinggian berbeda.   Penelitian deskriptif eksploratif ini dilakukan di Madiun dan Blitar.  Sampel diambil secara purposive sampling sebanyak 18 individu tanaman pada  tiga kultivar kakao di Madiun dan Blitar. Karakter morfologi sebanyak 120 karakter morfologi dan dianalisis dengan Principal Component Analysis untuk menentukan karakter penanda. Karakter ekologi yang digunakan adalah ketinggian tempat, suhu, kelembaban, dan pH serta karakter anatomi diamati menggunakan preparat whole mount daun agar dapat  menghitung kerapatan dan indeks stomata. Hasil penelitian menunjukkan bahwa ketinggian tempat menyebabkan perbedaan morfologi dan anatomi daun kakao sedangkan kualitas biji disebabkan oleh faktor naungan. Perbedaan ketinggian tempat berdampak pada karakter morfologi yang bervariasi terutama pada karakter daun, bunga, buah, dan biji, sedangkan anatomi daun berbeda pada kerapatan stomata dan indeks stomata. Tanaman kakao yang ternaungi akan memiliki indeks stomata lebih  tinggi dan  menghasilkan  biji lebih banyak dan berkualitas.

Cocoa (Theobroma cacao L.) or known as chocolate is one of Indonesia's leading commodities with high diversity. To increase the productivity of cocoa, superior cultivars are needed that are suitable for their environment so that a study of morphological and anatomical characters is needed. The purpose of this study was to determine the superior cultivars in terms of morphological, ecological, and anatomical characters and to know the relationship between the morphological and anatomical characteristics of Cocoa plants that grow at different heights.  This exploratory descriptive research was conducted in Madiun and Blitar. Samples were taken by purposive sampling as many as 18 individual plants in three cocoa cultivars in Madiun and Blitar. The morphological characters were 120 morphological characters and analyzed by Principal Component Analysis to determine the marker characters. The ecological characters used were altitude, temperature, humidity, and pH and anatomical characters were observed using whole mount leaf preparations in order to calculate the density and stomatal index. The results showed that the altitude caused differences in morphology and anatomy of the cocoa leaves, while the quality of the beans was caused by the shading factor. Differences in altitude have an impact on morphological characters that vary, especially on the characters of leaves, flowers, fruits, and seeds, while leaf anatomy differs in stomatal density and stomata index. Shaded cocoa plants will have a higher stomata index and produce more and quality beans.