PERSONAL DE APOYO
MASCIARELLI Oscar Alberto
artículos
Título:
Endophytic Bacteria Improve Seedling Growth of Sunflower Under Water Stress, Produce Salicylic Acid, and Inhibit Growth of Pathogenic Fungi
Autor/es:
G. FORCHETTI , M. IZAGUIRRE; O. MASCIARELLI , S. ALEMANO , D. ALVAREZ AND G. ABDALA
Revista:
CURRENT MICROBIOLOGY
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 2010 p. 485 - 493
ISSN:
0343-8651
Resumen:
Endophytic bacterial strains SF2 (99.9%
homology with Achromobacter xylosoxidans), and SF3 and
SF4 (99.9% homology with Bacillus pumilus) isolated
from sunflower grown under irrigation or drought were
selected on the basis of plant growth-promoting bacteria
(PGPB) characteristics. Aims of the study were to examine
effects of inoculation with SF2, SF3, and SF4 on sunflower
cultivated under water stress, to evaluate salicylic acid
(SA) production by these strains in control medium or at
Wa = -2.03 MPa, and to analyze effects of exogenously
applied SA, jasmonic acid (JA), bacterial pellets, and
bacterial supernatants on growth of pathogenic fungi
Alternaria sp., Sclerotinia sp., and Verticillum sp. Growth
response to bacterial inoculation was studied in two inbred
lines (water stress-sensitive B59 and water stress-tolerant
B71) and commercial hybrid Paraiso 24. Under both water
stress and normal conditions, plant growth following
inoculation was more strongly enhanced for Paraiso 24 and
B71 than for B59. All three strains produced SA in control
medium; levels for SF3 and SF4 were higher than for
SF2. SA production was dramatically higher at Wa =
-2.03 MPa. Exogenously applied SA or JA caused a significant
reduction of growth for Sclerotinia and a lesser
reduction for Alternaria and Verticillum. Fungal growth
was more strongly inhibited by bacterial pellets than by
bacterial supernatants. Our findings indicate that these
endophytic bacteria enhance growth of sunflower seedlings
under water stress, produce SA, and inhibit growth of
pathogenic fungi. These characteristics are useful for formulation
of inoculants to improve growth and yield of
sunflower crops.