title: Induction of Systemic Resistance against Aphids by EndophyticBacillus velezensisYC7010 via ExpressingPHYTOALEXIN DEFICIENT4inArabidopsis.
abstract: Aphids are the most destructive insect pests. They suck the sap and transmit plant viruses, causing widespread yield loss of many crops. A multifunctional endophytic bacterial strainBacillus velezensisYC7010 has been found to induce systemic resistance against bacterial and fungal pathogens of rice. However, its activity against insects attack and underlying cellular and molecular defense mechanisms are not elucidated yet. Here, we show that root drenching ofArabidopsisseedlings withB. velezensisYC7010 can induce systemic resistance against green peach aphid (GPA),Myzus persicae. Treatment of bacterial suspension ofB. velezensisYC7010 at 2 × 107CFU/ml toArabidopsisrhizosphere induced higher accumulation of hydrogen peroxide, cell death, and callose deposition in leaves compared to untreated plants at 6 days after infestation of GPA. Salicylic acid, jasmonic acid, ethylene, and abscisic acid were not required to confer defense against GPA inArabidopsisplants treated byB. velezensisYC7010. Bacterial treatment withB. velezensisYC7010 significantly reduced settling, feeding and reproduction of GPA onArabidopsisleaves via strongly expressing senescence-promoting genePHYTOALEXIN DEFICIENT4(PAD4) while suppressingBOTRYTIS-INDUCED KINASE1(BIK1). These results indicate thatB. velezensisYC7010-induced systemic resistance to the GPA is a hypersensitive response mainly dependent on higher expression ofPAD4with suppression ofBIK1, resulting in more accumulation of hydrogen peroxide, cell death, and callose deposition inArabidopsis.
authors.affiliation: Division of Applied Life Science (BK21 Plus), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University Jinju, South Korea.
authors.forename: Md Harun-Or-
authors.initials: MH
authors.lastname: Rashid
authors.affiliation: Division of Applied Life Science (BK21 Plus), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University Jinju, South Korea.
authors.forename: Ajmal
authors.initials: A
authors.lastname: Khan
authors.affiliation: Division of Applied Life Science (BK21 Plus), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University Jinju, South Korea.
authors.forename: Mohammad T
authors.initials: MT
authors.lastname: Hossain
authors.affiliation: Division of Applied Life Science (BK21 Plus), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University Jinju, South Korea.
authors.forename: Young R
authors.initials: YR
authors.lastname: Chung
keywords: Arabidopsis; Bacillus velezensis YC7010; PAD4; aphid; induced systemic resistance