title: Salinity stress resistance offered by endophytic fungal interaction between Penicillium minioluteum LHL09 and glycine max. L.
abstract: Endophytic fungi are little known for their role in gibberellins (GAs) synthesis and abiotic stress resistance in crop plants. We isolated 10 endophytes from the roots of field-grown soybean and screened their culture filtrates (CF) on the GAs biosynthesis mutant rice line - Waito-C. CF bioassay showed that endophyte GMH-1B significantly promoted the growth of Waito-C compared with controls. GMH-1B was identified as Penicillium minioluteum LHL09 on the basis of ITS regions rDNA sequence homology and phylogenetic analyses. GC/MS-SIM analysis of CF of P. minioluteum revealed the presence of bioactive GA(4) and GA(7). In endophyte-soybean plant interaction, P. minioluteum association significantly promoted growth characteristics (shoot length, shoot fresh and dry biomasses, chlorophyll content, and leaf area) and nitrogen assimilation, with and without sodium chloride (NaCl)-induced salinity (70 and 140 mM) stress, as compared with control. Field-emission scanning electron microcopy showed active colonization of endophyte with host plants before and after stress treatments. In response to salinity stress, low endogenous abscisic acid and high salicylic acid accumulation in endophyte-associated plants elucidated the stress mitigation by P. minioluteum. The endophytic fungal symbiosis of P. minioluteum also increased the daidzein and genistein contents in the soybean as compared with control plants, under salt stress. Thus, P. minioluteum ameliorated the adverse effects of abiotic salinity stress and rescued soybean plant growth by influencing biosynthesis of the plant's hormones and flavonoids.
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 701-702, Korea.
authors.forename: Abdul Latif
authors.initials: AL
authors.lastname: Khan
authors.forename: Muhammad
authors.initials: M
authors.lastname: Hamayun
authors.forename: Nadeem
authors.initials: N
authors.lastname: Ahmad
authors.forename: Javid
authors.initials: J
authors.lastname: Hussain
authors.forename: Sang-Mo
authors.initials: SM
authors.lastname: Kang
authors.forename: Yoon-Ha
authors.initials: YH
authors.lastname: Kim
authors.forename: Muhammad
authors.initials: M
authors.lastname: Adnan
authors.forename: Dong-Sheng
authors.initials: DS
authors.lastname: Tang
authors.forename: Muhammad
authors.initials: M
authors.lastname: Waqas
authors.forename: Ramalingam
authors.initials: R
authors.lastname: Radhakrishnan
authors.forename: Young-Hyun
authors.initials: YH
authors.lastname: Hwang
authors.forename: In-Jung
authors.initials: IJ
authors.lastname: Lee
mesh_terms: D060026:Endophytes / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D008969:Molecular Sequence Data; D012275:Oryza / Q000254:growth & development / Q000382:microbiology; D010407:Penicillium / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D018517:Plant Roots / Q000737:chemistry / Q000254:growth & development / Q000382:microbiology / Q000502:physiology; D054712:Salinity; D012965:Sodium Chloride / Q000378:metabolism; D013025:Glycine max / Q000737:chemistry / Q000254:growth & development / Q000382:microbiology / Q000502:physiology*; D013312:Stress, Physiological
chemical_list: D012965:Sodium Chloride