Pengaruh aplikasi bakteri perakaran pemacu pertumbuhan tanaman pada tiga genotipe cabai (Capsicum annum L.) terhadap pertumbuhan tanaman serta kejadian penyakit penting cabai

Abstract

In Indonesia, chilli was an important vegetable commodity refer to production area as well as it’s value, but production of chilli in Indonesia still very low. The low production was caused by a lack of proper cultivation techniques, seed quality, and pest and plant disease. Important disease that can decrease the production of chilli includes antrachnose disease, bacterial wilt, mosaic and mottle virus in chilli. The disease controlling effort that were recently developed and relatively safe for the environment, using Plant Growth-promoting Rhizobacteria (PGPR). The objective of this study was to determine the effect of PGPR usage, that were P. fluorescens PG01 isolates, B. polymixa BG25 and a mixture of both isolates (PG01 + BG25) against agronomic characters and incidence of important diseases in the three genotypes of chilli (IPB C5, C10 IPB, and Kopay) on the field. The experiment was performed from February until November, 2009 on farmer land were located on Desa Cibatok I, Kecamatan Cibungbulang, Kabupaten Bogor. The experiment was arranged in split plot design, were randomly treated with bacterial group as main plots and genotypes as subplots. Four levels main plots were PGPR treatments isolates PG01, BG25, PG01 + BG25, and without PGPR treatment as a comparison. The three subplots were C10 IPB, C5 IPB, and Kopay. In the experiment there were 12 treatment combinations, each treatment consisted of three replications, so there are 36 experimental units. Each experimental unit consisted of 20 plants, with a total 720 plants were tested. PGPR treatments significantly influenced the plant height and number of branches, but gave no significant effect on leaves number. The highest growth improvement on vegetative phase was occurred by the mixed bacterial treatment (PG01 + BG25). IPB C10, C5 genotypes and varieties of IPB Kopay have different agronomic characteristics measured on plant height, number of branches and number of leaves. PGPR treatment did not affect significantly to crop production and disease incidence (antraknosa, bacterial wilt, TMV, CMV, and ChiVMV). Antrachnose infections most commonly found in Kopay varieties, while the bacterial wilt infection occurs more frequently in genotypes IPB C5.