Handling Soybean ( Glycine max L.) Under Stress - Crop Improvement: New Approaches and Modern Techniques - page 417

Chapter 15
Handling Soybean ( Glycinemax L.) Under Stress
Mohammad Miransari
Abstract Soybean is among the most important leguminous plants with the abil-
ity to establish symbiotic association with the N-fixing bacteria, Bradyrhizobium
japonicum . With respect to the environmental and economical significance of N fix-
ation, there has been extensive research work regarding the production of legumes
including soybean under different conditions. Soils are usually subjected to some
kind of stress including salinity, acidity and suboptimal root zone temperature. One
of the most important processes, affecting the performance of soybean under stress
is the inhibited exchange of the signal molecules, specifically genistein, between
the host legume and B. japonicum during the initiation of symbiosis. Interestingly,
inoculation of B. japonicum with the signal molecule genistein has partially or
completely alleviated the stress. It is also of significance to determine the right
combination of N-fertilization and rhizobium inoculums when planting leguminous
including soybean. The use of breeding techniques may also be among the effective
methods of improving soybean performance under stress. In this chapter some of
the most important advances regarding the performance of soybean under different
conditions including stress with respect to the molecular techniques are reviewed.
Some future perspectives are also presented, the production of tolerant plants and
microbes are among the most important ones.
Introduction
Soybean ( Glycine max L.) is a crop plant belonging to the leguminous family and
is widely cultivated in different parts of the world. It is a source of food, with high
protein rate, containing useful nutrients. It is the major leguminous crop plant rep-
resenting 50 % of the crop legume production and 68 % of the total crop production
in the world. It is able to develop symbiotic association with the bacteria from the
rhizobium family, Bradyrhizobium japonicum , fixing atmospheric N 2 . The amount