Paromomycin Derived from Streptomyces sp. AG-P 1441 Induces Resistance against Two Major Pathogens of Chili Pepper.
This is the first report that paromomycin, an antibiotic derived from Streptomyces sp. AG-P 1441 (AG-P 1441), controlled Phytophthora blight and soft rot diseases caused by Phytophthora capsici and Pectobacterium carotovorum, respectively, in chili pepper (Capsicum annum L.). Chili pepper plants treated with paromomycin by foliar spray or soil drenching 7 days prior to inoculation with P. capsici zoospores showed significant (p < 0.05) reduction in disease severity (%) when compared with untreated control plants. The disease severity of Phytophthora blight was recorded as 8% and 50% for foliar spray and soil drench, respectively, at 1.0 ppm of paromomycin, compared with untreated control, where disease severity was 83% and 100% by foliar spray and soil drench, respectively. A greater reduction of soft rot lesion areas per leaf disk was observed in treated plants using paromomycin (1.0 μg/ml) by infiltration or soil drench in comparison with untreated control plants. Paromomycin treatment did not negatively affect the growth of chili pepper. Furthermore, the treatment slightly promoted growth; this growth was supported by increased chlorophyll content in paromomycin-treated chili pepper plants. Additionally, paromomycin likely induced resistance as confirmed by the expression of pathogenesis-related (PR) genes: PR-1, β-1,3-glucanase, chitinase, PR-4, peroxidase, and PR-10, which enhanced plant defense against P. capsici in chili pepper. This finding indicates that AG-P 1441 plays a role in pathogen resistance upon the activation of defense genes, by secretion of the plant resistance elicitor, paromomycin.
Microbial Plant Activation Laboratory, Agricultural Microbiology Division, National Academy of Agricultural Science (NAAS), RDA, Jeonju 55365, Republic of Korea.
Kotnala
K
Balaraju
Korean Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea.
Chang-Jin
CJ
Kim
Korean Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea.
Dong-Jin
DJ
Park
Department of Horticulture, Hankyung National University, Ansung 17579, Republic of Korea.
Ki-Woong
KW
Nam
Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, P.R. China.
Kecheng
K
Zhang
Microbial Plant Activation Laboratory, Agricultural Microbiology Division, National Academy of Agricultural Science (NAAS), RDA, Jeonju 55365, Republic of Korea.
Mee Kyung
MK
Sang
Microbial Plant Activation Laboratory, Agricultural Microbiology Division, National Academy of Agricultural Science (NAAS), RDA, Jeonju 55365, Republic of Korea.
Kyungseok
K
Park
D002212:Capsicum / Q000382:microbiology*; D060467:Disease Resistance / Q000187:drug effects*; D010303:Paromomycin / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D010838:Phytophthora / Q000187:drug effects*; D010935:Plant Diseases / Q000382:microbiology / Q000517:prevention & control; D013302:Streptomyces / Q000737:chemistry* / Q000378:metabolism
D010303:Paromomycin
Chili pepper; Phytophthora blight; Streptomyces sp; induced resistance; paromomycin; soft rot