Epiphytic Bacteria Associated with the Bryophyte Funaria hygrometrica: Effects of Methylobacterium Strains on Protonema Development

Abstract

Bacteria represent a substantial fraction of the microorganisms that inhabit leaf surfaces. We collected samples of the moss Funaria hygrometrica (L.) in the field and analysed the epiphytes on the gametophyte by the agar impression method and scanning electron/fluorescence microscopy. On the phylloid surface numerous bacteria were detected, notably in the grooves between adjacent lamina cells. Methanol‐ammonium salts agar surfaces impressed with isolated phylloids of green gametophytes resulted in the growth of methylotrophic colonies. Two Methylobacterium strains (M. mesophilicum and M. sp., isolated from the Funaria phylloids) were found to simulate the well‐known effect of cytokinin application on bud formation in Funaria protonemata. In addition, Methylobacterium inoculation promoted the growth of protonemal filaments. The significance of this novel Methylobacterium‐land plant interaction is discussed.

Impact of Pink Pigmented Facultative Methylotroph and PGRs on Water Status, Photosynthesis, Proline and NR Activity in Tomato under Drought

“…Using a variety of biochemical and cytological methods, it has been shown that microbes of the genus Methylobacterium produced cytokinin (Koenig et al, 2002). The "classical" phytohormone auxin is also produced and secreted by different strains of Methylobacterium (Hornschuh et al, 2002). Basile et al, (1985) found that the PPFMs influence plant growth by production of phytohormones, such as IAA, cytokinins and vitamins.…”

Methylobacteria isolated from bryophytes and the 2-fold description of the same microbial species

“…4,8 the authors as PPFMs (see ref. 6), stimulated organ growth and reproductive development, compared with sterile controls. Based on these data, the authors proposed that a specific association between these microbial plant surface dwellers (PPFMs) and the liverwort may exist.…”

“…12 Numerous subsequent studies revealed that methylobacteria and bryophytes have, in the course of evolution, established a symbiotic relationship. [6][7][8] In their detailed study, Tani et al 3 document that bacterial strains that belong to the taxa M. adhaesivum, M. brachiatum, M. extorquens, M. marchantiae, M. komagatae and M. radiotolerans, and novel lineages close to M. adhaesivum, most of which were isolated from various bryophytes, are efficient colonizers of the phyllosphere. Based on these data, they speculate that microbes of the genus Methylobacterium preferentially colonize the above groundphytosphere of these "living fossil plants."…”

“…This is not correct, since the type strain was isolated by us in 2002, and the first paper describing the morphology of the cells, and their ability to secrete cytokinines, was published ten years ago. 6 Two additional articles on Methylobacterium sp F3.2 followed in 2006 and 2007. 7,8 We also noticed that the information concerning carbohydrate metabolism are erroneous.…”

Beneficial microbiomes: Biodiversity and potential biotechnological applications for sustainable agriculture and human health

“…The phyllospheric microbes may perform an effective function in controlling the airborne pathogens inciting plant disease. Microbes on leaf surface are said to be extremophiles as they can tolerate low/high temperature (5-55°C) [15,[23][24][25][26][27].…”