Download Azospirillum and related microorganisms

Azospírillum VI
and Related Microorganisms
Genetics - Physiology - Ecology
Edited by
István Fendrik Maddalena del Gallo Jos Vanderleyden
Miklos de Zamaroczy
NATO ASI Series
Series G: Ecological Sciences, Vol. 37
jced bacteria.
in the infectíon of cercáis wilh
R.PastorelU, A.Gori and F.Favilli
Dipartimento di Scienze e Tecnologie Alimentari
Sez. di Microbiología Applícata, University of Flo
Piazzale delle Cascine, 27 - 50144 Firenze, Itaty.
pirillum inoculation technology:
iol 36: 591-608
ic responses in plant growth, yield
ilion with Azospirillum brasilense
(1986) Effect of inoculation of
vn wheat. Plant Soil 95:
ME, Littell RC, Galaher NR,
Is and hybrids to inoculation with
) Establishment of Azospirillum
.¡ochen. 21:59-64
Genotype-dependent response to
in Brassica júncea L. Curr. Sci.
88) Field inoculation of sorg'hum
•edicae. Plant Soil. 110:
Abstract
Several bacterial strains were isolated from the rh
classifíed in the genera Enterobacter, Pseudomo
on the basis of their morphological and biochem
of colonizatíon and adhesión of these bacteria to
microscopy have been carried out.
Keywords: rhizosphere, adhesión, root surface, S
biofertilizer in intensive wheat
ilion of Azospirillum spp. Appl.
Introduction
ig roots of nonleguminous plañís.
Is) Nauka Moscow (in Russian)
Chmeleva ZV (1989) Bacteria of
ivily of nonhomologous plañís.
The ability of rhizobacteria to colonize roots is
competition of the bacterium in the rhizosphere.
;arl millet cultivars to inoculation
that are important to promote competitiveness,
surface. Living firmty anchored to root, bacteria
(Mentéis e/a/., 1989).
In this work we have investigated the capacity t
bacterial strains isolated from the rhizosphere of i
described by Bazzicalupo et al. (1985). Plañís
to root surface of maize and w
th cabinet (16h light, 21°C; 8h dark, 17°C) for
Figure 1A shows how most
epidemial cells in tiie root-hair r
washed inoculated-roots were fixed for 18h at
connected to root surface an
jhosphate buffer (pH 7.0), washed three times,
coíonization was observed near
le and dehydrated in a grade series of ethanol.
to be attached to the cell surfac
al Point Dryer 020 Balzers) mounted on stubs,
while the other strains along the
i05 scanning electrón microscope (Haahtela et
The majority of the bacterial c
aggregations, with the exception
the surface of roots (Fig. ID).
Azospirillum snáBacittus strain
observations provided evidence
pecies
zospirittum lipoferum
zospirillum lipoferum
'nteróbacter cloacae
'nterobacter sakazakii
seudomonas sp.
zotobacter chroococcum
acillus subtilis
acüius megaiherium
Conclusión*
Bacteria tested prefer to colon
exúdales; the modality of adhe
seems to be supported by fibrilla
Internal root coíonization has b
Azospirillum strains are able
Á2ospirillum penetraíion into i
understood (Bashan and Levan
penetraíion of bacteria in root in
Figure 1. Scanning electrón micrographs: (A) EnunAp3 adherec ~
maize root, X655; (B) EnunB12 anchored to root surface
fibrillar materal, X5000; (C) EnunEtS anchored to maize roer bj
a single pole of the bacterial cell, X2500, (D) EnunB12 femé:
aggregations on maize root surface, X600; (E) EnunAp2 ad'r.= r^~
to root hair surface, X2620; (F) internal colonization of r = _ : ^
root by EnunAp3, X1250.
Azospirülum as a challenge for agriculture. Can
Bazácalupo M, Cresta E and Favilli F (1985) An i
wheat association. In Azospirülum DI: Genetic
Springer-Verlag, pp. 139-146
de Freitas JR and Germida JJ (1990) A root ti
rhizobacteria interactíons. Appl Microbiol Biote
Haahtela K, Laakso T, Nurmiaho-Lassila EL and
of Poa pratensis and Triticum aestivum
Enterobacter máAzospirillum. Plant and Soil
Holt JG (1984) Bergey's manual of systematic ba
Wilkins Co. Baltimore.
Michiels K, Vanderleyden J and Van Gool A (1
review. Biol Fértil Soils 8:356-363
(A) EnunAp3 adhered to
to root surface by
hored to maize root by
30, (D) EnunB12 formad
; (E) EnunAp2 adhered
colonization of maize