BACILLUS SUBTILIS AS GROWTH PROMOTOR IN HYDROPONICALLY GROWN TOMATOES UNDER SALINE CONDITIONS

The gram-positive bacterium Bacillus subtilis is known to positively influence plant growth, vitality, and the ability of the plant to cope with pathogens often resulting in higher yield.
These beneficial effects are documented in field crops, where it has been ascribed to abiotic stress release.
However, little is known about the mechanism by which B. subtilis interacts with the plant.
Therefore, we tested a specifically selected strain of B. subtilis (FZB24) for its ability to help hydroponically grown tomato plants to withstand salinity stress.
The basic nutrient solution was 2.5 mS/cm EC with the addition of 2 and 4 mS/cm NaCl EC plus 5 mmol CaCl in all treatments to reach 5.4 and 7.4 mS/cm EC. In addition, the high salinity level (EC NaCl 4) was inoculated with the plant growth promoting bacteria B. subtilis in the root zone.
Plant growth parameters including element con-centrations in plant tissues were examined on tomato plants grown under 3 salinity regimes in an environmentally controlled greenhouse.
Marketable yield was signifi-cantly reduced in the high salinity treatment as compared to the control without NaCl.
In addition, the high salinity treatment with B. subtilis had even lower yield despite improved vegetative plant growth.
The element composi-tion/concentration in the leaves is discussed according to salinity levels.

VII International Symposium on Protected Cultivation in Mild Winter Climates: Production, Pest Management and Global Competition

M. Woitke, H. Junge, W.H. Schnitzler

Bacillus subtilis, tomato, Lycopersicon esculentum Mill., growth, yield, salinity, nutrient uptake

https://doi.org/10.17660/ActaHortic.2004.659.48