Studi taksonomi ubi jalar (Ipomoea batatas (L.) Lam.) di Tawangmangu dan gunung Kawi berdasarkan karakter morfologi dan profil kromatografi lapis tipis senyawa gologan flavonoid

SUHARNANIK, Drs. Purnomo, M.S

2008 | Tesis | S2 Biologi

Studi taksonomi ubi jalar di Tawangmangu dan Gunung Kawi dilakukan berdasarkan karakter morfologi dan profil KLT senyawa golongan flavonoid. Penelitian ini bertujuan untuk mengetahui macam kultivar, menentukan sifat khas setiap kultivar, dan menentukan hubungan kekerabatan fenetik antar kultivar ubi jalar yang dibudidayakan di Tawangmangu dan Gunung Kawi. Koleksi sampel dilakukan di Tawangmangu dan Gunung Kawi. Karakterisasi morfologi dilakukan pada organ batang, daun, bunga, dan umbi. Profil senyawa golongan flavonoid dideteksi menggunakan KLT dilakukan terhadap bagian daun dan umbi. Data diskor dan dikode menggunakan metode two-state dan multistate characters, ditentukan nilai mean dan standar deviasinya, kemudian distandarisasi untuk mendapat data dalam status 0-1. Selanjutnya dihitung nilai indeks similaritas menggunakan rumus simple matching coefficient. Pengelompokkan kultivar menggunakan metode agglomerative UPGMA untuk membentuk dendrogram. Hasil penelitian menunjukkan di Tawangmangu terdapat lima kultivar ubi jalar, yaitu kultivar Sari, Biru, Paket, Ayumurasaki (Biru mangsi), dan Kola’an sedangkan di Gunung Kawi terdapat delapan kultivar ubi jalar, yaitu kultivar Genjah sawo, Mantang, Kuning waluh, Mongkrong, Gatut koco, Kangkungan, Gentho, dan Ayumurasaki (Biru mangsi). Sifat khas setiap kultivar secara morfologi terutama adalah pada pola warna baik pada batang, daun, bunga, maupun umbi. Secara KLT setiap kultivar pada daun mengandung flavonoid golongan flavonol dan flavon, sedangkan pada umbi mengandung golongan flavonol kecuali kultivar Gatut koco. Pada umumnya pada umbi tidak mengandung golongan flavon kecuali kultivar Paket dan Kuning waluh. Kultivar yang mempunyai warna kulit umbi merah keunguan atau ungu tua mengandung golongan antosianin. Dendrogram yang terbentuk menunjukkan bahwa diantara 12 kultivar ubi jalar dapat dikelompokkan menjadi tiga kelompok yang diduga merupakan takson di bawah tingkat spesies yang berbeda.

A study on taxonomy of sweet potatoes in Tawangmangu and Gunung Kawi is carried out based on morphological characteristics and TLC flavonoid profile compound groups. The objective of the study was to identify the types of cultivar, particular characteristics of each cultivar, and intercultivar phenetic relationship of sweet potatoes cultivated in Tawangmangu and Gunung Kawi. Samples were taken from the collection in Tawangmangu and Gunung Kawi. Morphological characterization was assessed based on stem, leaves, flower, and tuber. Flavonoid groups profiling was detected using TLC from leaves and tuber. Data were scored and coded using two-state and multistate characters methods. Mean value was determined and the deviation standard was calculated to facilitate standarization of the data which then come in the form of 0-1 data sets. Then, index of similarity was calculated using sample matching coefficient formula. The grouping of cultivars was carried out using UPGMA agglomerative method to create a dendrogram. There were five cultivars of sweet potatoes, i.e. Sari, Biru, Paket, Ayumurasaki (Biru mangsi) and Kola'an in Tawangmangu and there were eight cultivars in Gunung Kawi, i.e. Genjah sawo, Mantang, Kuning waluh, Mongkrong, Gatut koco, Kangkungan, Gentho, and Ayumurasaki (Biru mangsi). Specific morphological characteristics of each cultivar identified in this study were: color pattern either in the stem, leaf, flower, and tuber. Based on TLC, the cultivars have flavonoid of flavonol and flavon group in their leaves. Whereas in the tuber flavonol was identified in all cultivars except in Gatut koco. Generally there was no flavon in tuber except in cultivar of Paket and Kuning waluh. Cultivars having red purple or dark purple tuber skin contained antosianin. The dendrogram indicated that 12 cultivars of sweet potatoes could be recognized as three different groups suggested to be infraspecific taxa.

Kata Kunci : Ubi jalar,Morfologi,Kultivar,Flavonoid,Hubungan kekerabatan fenetik,Tawangmangu,Gunung Kawi, cultivar, sweet potatoes, morphology, flavonoid, phenetic relationship, Tawangmangu, Gunung Kawi