Promotion of apple tree growth and fruit production by the EBW-4 strain of Bacillus subtilis in apple replant disease soil

Abstract

A field trial was conducted near Kelowna, British Columbia, to determine the effect of biological treatments alone and in combination with formalin fumigation in apple replant disease soil. The response was measured by the increase in cross-sectional trunk area, total shoot growth, and fruit yield of McIntosh apple trees on M.26 rootstock. The postplanting drench application of strain EBW-4 of Bacillus subtilis alone was consistently effective in increasing cross-sectional trunk area for 5 years, total shoot growth for 4 years, and fruit yield for 3 years. The biological agent EBW-4 of B. subtilis in combination with formalin fumigation was also effective in promoting total shoot growth and cross-sectional trunk area. The application of formalin fumigation alone was effective in increasing shoot growth for 2 years and cross-sectional trunk area for 1 year only. This treatment did not increase fruit yield for 3 years. The consistent performance of strain EBW-4 of B. subtilis during 1986-1991 indicates that this bacterium has the potential for biological control of replant disease under orchard conditions in the Okanagan Valley of British Columbia.

Influence of plant growth-promoting rhizobacteria (PGPR) on blackberry (Rubus glaucus Benth. cv. thornless) growth under semi-cover and field conditions

“…When performing mineral fertilizations, fixation of soil nutrients and their leaching make difficult the presence of these available minerals to plants, which had achieved a decreasing in the fertilization efficiency. In contrast, strains of B. subtilis in apple showed that effects on plant growth linked to the mechanisms of action of this PGPR could last up to five years (Utkhede & Smith, 1992). In Rubus glaucus cv.…”

“…(De-Bashan, Hernandez, Bashan & Maier, 2010). Moreover, in sweet cherry (Prunus avium (L.) L.), PGPR improved performance and therefore flowering (Esitken, Pirlak, Turan & Sahin, 2006) and, in apple the effect on yield and harvest, implicitly linked to flowering, may last up to three years under the inoculation of these PGPR (Utkhede & Smith, 1992). In blackberry crops, the number of flowers per cluster is a good crop indicator due to its high fruit set percentage (89%).…”

Apple Replant Disease: Causes and Mitigation Strategies

“…Already 25 years ago, Utkhede and Smith (1992) reported the promotion of apple tree growth and fruit production in a former ARD soil after inoculation with a strain of Bacillus subtillis, which showed biocontrol activities against various pathogens. The authors could prove that the inoculation procedure was more effective than a classical formalin fumigation, mainly, as it did not only increase shoot growth and the cross-sectional trunk area but resulted in higher yields, too.…”

Biocontrol ofBacillus subtilisagainst Infection of Arabidopsis Roots byPseudomonas syringaeIs Facilitated by Biofilm Formation and Surfactin Production

“…Interestingly, poor root colonization by PR may result in decreased biocontrol activity (Schippers et al, 1987). One beneficial rhizobacterium is Bacillus subtilis, which is ubiquitous in soil, can promote plant growth, protect against fungal pathogen attack ( Utkhede and Smith, 1992;Asaka and Shoda, 1996;Emmert and Handelsman, 1999), and play a role in the degradation of organic polymers in the soil (Emmert and Handelsman, 1999). Among the first successful biocontrol agents used against insects and pathogens were members of the genus Bacillus (Powell and Jutsum, 1993).…”