Electronic Theses and Dissertation

Penelitian ini bertujuan untuk mendapatkan isolat rizobakteri yang mampu
berperan sebagai kandidat agen biokontrol dalam menghambat pertumbuhan koloni patogen
P. palmivora secara in vitro. Disamping itu penelitian ini bertujuan untuk mengetahui
apakah jenis rizobakteri indigenous dapat berperan sebagai kandidat agens pemacu
pertumbuhan tanamandengan isolat patogen P. palmivora. Penelitian dilaksanakan dari
bulan Oktober 2020 sampai bulan Mei 2021. Penelitian menggunakan rancangan acak
lengkap non factorial. Faktor yang diteliti yaitu jenis isolat rizobakteri indigenous sebanyak
8 jenis isolat. Pengamatan yang dilakukan mencakup daya hambat pertumbuhan koloni
pathogen, laju penghambatan, aktivitas enzim protease, kemampuan melarutkan fosfat,
produksi IAA, produksi HCN, produksi dan produksi senyawa siderofor. Hasil penelitian
menunjukkan bahwa kemampuan isolat rizobakteri indigenous GM 8/1 dan GM 7/10
merupakan dua isolat yang memiliki daya hambat sanat tinggi. Sedangkan laju
penghambatan relative lebih tinggi diperoleh dari isolat GM 8/3. Sementara aktivitas enzim
protease tertinggi terdapat pada isolat GM 5/6 dan isolat GM 7/10. Kemampuan melarutkan
fosfat tertinggi diperoleh pada isolat rizobakteri GM 7/10. Isolat rizobakteri yang
menghasilkan senyawa IAA lebih tinggi pada isolat GM 8/1, GM 8/3 dan GM 8/11. Produksi
senyawa HCN diperoleh pada 3 isolat rizobakteri yaitu GM 5/6, GM 7/10 dan GM 8/8.
Semua isolat mampu memproduksi senyawa siderofor.

This study aimed to obtain rhizobacteria isolates that capable to act as candidates for biocontrol agents in inhibiting the growth of P. palmivora pathogenic colonies in vitro. In addition, this study aimed to know whether indigenous rhizobacteria could be acted as candidates for plant growth promoting agents with pathogenic isolates of P. palmivora. The study was conducted from October 2020 to May 2021. The study used a randomized block design. The factors studied were the types of indigenous rhizobacteria isolates as many as 8 types of isolates. Observations were made including the inhibition of the growth of pathogenic colonies, the rate of inhibition, the activity of the protease enzyme, the ability to dissolve phosphate, the production of IAA, the production of HCN, and the production of siderophore compounds. The results showed that the ability of the indigenous rhizobacteria isolates GM 8/1 and GM 7/10 were the two isolates that had very high inhibitory power. While the relatively higher rate of inhibition was obtained from isolate GM 8/3. Meanwhile, the highest protease enzyme activity was found in isolate GM 5/6 and isolate GM 7/10. The highest phosphate solubilizing ability was obtained in GM 7/10 rhizobacteria isolate. The rhizobacteria isolates that produced IAA compounds were higher in isolates GM 8/1, GM 8/3 and GM 8/11. The production of HCN compounds was obtained in 3 rhizobacteria isolates, namely GM 5/6, GM 7/10 and GM 8/8. All isolates were able to produce siderophores.