EXPRESSION STUDY OF MaACO AND MaACS2 GENES IN SUSCEPTIBLE AND RESISTANT BANANA TO BLOOD DISEASE

• Main Author: PUTRI MEITASARI, DWIANTY
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/34273
• Institution: Institut Teknologi Bandung

Indonesia is one of the tropical fruits producer countries such as banana. Genetic diversity of banana is very high in Indonesia (more than 200 have been identified from more than ~1000). However, banana genetic information remains limited, particularly related to disease resistance. Blood Disease is one of the common disease caused by Blood Disease Bacterium (BDB) which cause huge loss of banana production in Indonesia. Gene family of MaACO and MaACS2 play role in ethylene biosynthesis which is responsible for respon of plant defense mechanism. However, studies regarding expression of such genes on plant defense mechanism on blood disease are not available. This study aimed to observe effect of infection Blood Disease Bacterium (BDB) on MaACO and MaACS2 expression of susceptible and resistant banana to blood disease. BDB isolates were identified from blood disease-infected Nangka banana (AAB group) in Balai Penelitian Buah Tropika, Subang. BDB isolate was 99%-100% homologous to BDB by PCR with a pair of Ralsonia solanacearum (RS) primer and a pair of BDB spesific primer. In this study, there were two banana cultivars observed, Mas Kirana (AA group) as a resistant candidate to blood disease, and Klutuk (BB group) as a susceptible candidate to blood disease. BDB injection in suspension of 2,5 ml BDB with density of 107 cfu/ml, was conducted in 6 months old banana on 5 cm above ground surface. Symptoms development was observed in injected banana. Gene expression of MaACO and MaACS2 was measured with Reverse Transcriptase (RT) PCR. Results showed that blood disease symptoms were present in BDB-injected banana in Klutuk group after 1 week, which were shown as flaccid, withered leaf, yellowish, a reddish-brown discoloration of stem, corm turned brown and rot, whereas there was no symptoms found significantly in Mas Kirana group as a resistant candidate to BDB. Molecular analysis showed MaACO and MaACS2 were not significantly in gene expression both in Mas Kirana and Klutuk after BDB injection.