PENGARUH PLANT GROWTH PROMOTING RHIZOBACTERIA (Bacillus subtilis dan Pseudomonas fluorescens) TERHADAP PERTUMBUHAN DAN HASIL TANAMAN KENTANG (Solanum tuberosum L.) PADA KETINGGIAN 800 METER DIATAS PERMUKAAN LAUT

One of the important diseases that attack the potato crops in the medium latitude is bacterial wilt caused by Ralstonia solanacearum. Needed a technologies that use of B. subtilis and P. fluorescens to enhance the resilience of the potato plants against diseases and for increased growth and yield of potato crop at latitude of 800 masl (meters above sea level). The results showed that the application of a combination of bacteria B. subtilis and P. fluorescens is able to increase the length of the plant, number of leaves and potato plant resistance against pathogen attack. On weight of tuber varieties DTO 28 observations, application of a combination of bacteria B. subtillis + P. fluorescens per plant, per meter and per hectare be able to increas 92.41% compare with control treatment without bacterial inoculation. In the treatment of Granola Kembang variety, observations per plant, per square meter and per hectare application of B. subtillis bacteria, P. fluorescens bacteria and application of a combination B. subtillis + P. fluorescens bacteria increased 90%, 100% and 122.67% compared with control treatment without inoculation of bacteria. The potato plant resistance to pathogen attack of R. solanacearum, DTO 28 variety on bacterial combination of B. subtilis + P. fluorescens treatment be able to pressing the attack of R. solanacearum compare with control treatment by 55.08%. On Granola Kembang variety, attacks R. solanacearum on potato treatment applications bacteria of B. subtilis, P. fluorescens bacteria and application combinations bacteria B. subtilis + P. fluorescens is able to pressing the attack amounted to 72.19%, 88.95% and 94.47% compared to Granola Kembang with control treatment