Page 2 Plant-Bacteria Interactions Edited by Iqbal Ahmad, John ...

276j 14 Salt-Tolerant Rhizobacteria: Plant Growth Promoting Traits
were found very effective in controlling soilborne diseases and pathogens. These
characteristics are useful in producing commercial inoculants for routine use to
support plant production in stressed environments.
14.9
Future Directions
Although a number of rhizobacteria have been identified that are capable of tolerating
extreme climates, their potential synergistic effects on plants or antagonistic
effects on soilborne pests and diseases are still questionable. However, they have
potential use to support plant establishment and growth under dry and saline
environments. To further understand the highly complex nature of microbial adaptation
and response to alterations in the biological, chemical and physical environment
of the rhizosphere remains a significant challenge for plant biologists and soil
microbiologists. Future research must address the following:
. Proper understanding of the behavior of rhizosphere microbes from a wide range
of plants under extreme climatic conditions;
. Isolation, identification and comparison of rhizospheric microbes to develop a
genetic data bank; and
. Development of more effective microbial strains, with longer shelf lives, as a
biocontrol to supplement and/or complement chemical fertilizers and pesticides
in agriculture.
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