Gene expression of soybean root tips under water deficits

As an important adaptation to drought stress, several agronomic species, such as soybean and maize, can maintain the primary root substantial elongation rates at low water potentials, whereas shoot growth stops completely. In soybean, kinematic characterization of the spatial patterns of cell expansion within the root elongation zone showed that at low water potentials, elongation rates were preferentially maintained toward the root apex but were progressively inhibited at more basal locations, resulting in a shortened growth zone. To explore the molecular mechanism of root elongation in response to water stress, we set out to examine the expression of soybean genes in different root regions after 5 hours (5h) and 48 hours (48h) water stress treatment using the Affymetrix Soybean GeneChip containing 37,500 G. max probe sets. We examined spatial-temporal expression of soybean (cv.Magellan) genes in roots under water deficits. Overall, twenty-seven samples, including three biological replicates for each sample, were analyzed.