Isolation of Frankia from nodules of Casuarina equisetifolia

Abstract

Using the simple serial dilution technique, five strains of actinomycetes were isolated from nodules of Casuarina equisetifolia. In spite of the fact that these strains did not nodulate the host plant, they were assumed to belong to the genus Frankia because they possessed the morphological and cultural characteristics now admitted as specific to this genus.

Extranodular growth of Frankia on Casuarina equisetifolia

“…Sporangia in the ENF colonies exhibited a wide range of sizes and shapes (Fig. 6), much like those observed in pure cultures of Fraizkia from Casuarirza [3] or other host plants (e.g. [9]).…”

Isolation offrankiastrains from root nodules ofmyrica rubra

“…In the current study, lobe tips of newly developed nodules in water culture were used for the isolation of the endophytes and the outer cortical layers of the nodule lobes were peeled off to eliminate most of the contaminants (DIEM and DOMMERGUES 1983). Moreover, the double layer agar technique described by DIEM et al (1982) was used with slight modifications. The double layer agar technique is advantageous in that (i) contaminants do not necessarily overgrow the Frankia colonies, and (ii) microaerophilic Frankia colonies are not directly exposed to the atmosphere.…”

“…Endophytes retained on the 25 ym screen were released in the FMS by vigorous shaking. For the isolation of Frankia strains in the agar medium, the double layer agar technique described by DIEM et al (1982) was used with slight modifications. The suspension of endophytes was mixed in 15.5 ml of 1.0~/o agar-FMS, previously autoclaved and cooled.…”

“…The Frankia endophytes were successfully isolated from root nodules of Comptonia peregrina by CALLAHAM et al (1978). Thereafter numerous strains of Frankia were isolated from various plants (BURGGRAAF et al 1981 ;BENSON 1982;DIEM et al 1982;BURGGRAAF and SHIPTON 1983;ZANG et al 1984). Recently JtABIN et aL (1985) reported that nodules were not * Present address: Iwata Experimental Station, Japan Tobacco Inc., Iwata-gun, Shizuoka, 438 Japan.…”

Biologie et diversité génétique des souches deFrankiaassociées aux Casuarinacées

“…Depuis 1983, date du premier isolement d'une souche de Frankia a partir de Casuarinacees, capable de renoduler sa plantehote d' origine, seulement quelques souches sont actuellement disponibles (Diem et at., 1982 ;Diem et al, 1983 ;Diem et Dommergues 1985 ;Zang et al 1984 ;Zang et Torrey 1985a, b ;Girgis et al, 1990 ;MUller et al, 1991 ;Savoure et Lim, 1991 ;Girgis et Schwencke, 1993). Ceci semble du a differents facteurs.…”