Comparison of Plant Growth Promoting Rhizobacteria (PGPR) Diversity and Dynamics During Growth of Cilembu Sweet Potato (Ipomoea batatas L var. Rancing) in Cilembu and Jatinangor Site, Indonesia

Abstract

The growth and quality of Cilembu Sweet Potato is influenced by the colonization of plant growth promoting rhizobacteria (PGPR). In this study, cultivation medium (soil) were sampled on different period of growth time (0 – 4 months) in two different locations, Cilembu (LCI) and Jatinangor (LJA). Isolation were done based on several selective ability of PGPR, followed by sequencing using 16S rRNA. Based on soil properties, LJA contains more clay and slightly more acidic than the LCI, where the C/N ratio at LCI is higher than LJA (13:10). 17 isolates of bacteria and two isolates of Actinomycetes were found in LCI samples, while LJA samples had 17 isolates of bacteria and one isolate of Actinomycetes. The highest abundance of rhizosphere bacteria at LCI and LJA belongs to Firmicutes division, with 58% and 83% of presence, respectively. PGPR diversity increases in LCI site, while it drops after the third month in LJA site. This result indicates that PGPR diversity in LCI site may contribute in taste establishment of Cilembu Sweet Potato.

Keywords

• cilembu sweet potato
• pgpr
• rhizosphere
• ipomoea batatas