Expression of PR1 and PR3 Resistance Genes in In Vitro Assay of Banana Plantlets Cultivars Kepok and Mas Infected with Fusarium oxysporum f.sp cubense Tropical Race 4 (Foc TR4).

• Main Author: Rizanti - NIM: 10614038 , Meirifa
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/28840
• Institution: Institut Teknologi Bandung

<p align="justify">Banana is the fourth highest consumed fruit in Indonesia. However, its productivity does not increase significantly because of several factors including plant diseases. Panama disease caused by Fusarium oxysporum f.sp. cubense (Foc) is one of the main disease affecting banana production. The most abundant strain of Foc found in Indonesia is the Foc TR4. It causes economic losses due to the decline in banana fruit production. Therefore, the aim of this study is to determine the banana plants resistance to Panama disease by examining the expression of pathogenesis 1 and 3 related genes (PR1 and PR3) on bananas infected with Foc TR4. In this study, mas and kepok cultivars were used for the in vitro culture assay. The banana culture was infected in the same physiological age, ie having 4 leaves. Foc TR4 used was confirmed morphologically by microscope observation of the culture and molecularly using the Foc TR4 specific primers. Foc TR4 infection was carried out on sugar-free interaction medium for 14 days. Morphological observation was carried out during the infection period, while analysis for the expression of PR1 and PR3 genes was carried out on the 4th, 8th, and 14th days after infection using semiquantitative method in imageJ. Morphological and molecular observations of BKK3 and BKS3 confirmed that the Foc strain used was Foc TR4. The infection results on both banana cultivars showed that morphologically, the banana group infected with Foc TR4 showed a symptoms of panama disease while the negative control did not. Kepok cultuvar showed more obvious symptoms of the disease compared to Mas cultivar, which was a more severe yellowing in leaf colour with the necrosis spots. ImageJ results showed that the expression of PR1 and PR3 genes in both mas and kepok infected cultivar was higher than the negative control, but both resistance genes were expressed higher in the mas cultivar. The highest expression of both genes occurred on day 4. With this results, it is suspected that the expression patterns of PR1 and PR3 genes correlate with banana resistance to Foc TR4, and Kepok cultivar is relatively more susceptible to Foc TR4 than the mas cultivar. <p align="justify">