S elenium is an essential element for humans, animals and some species of micro-organisms; however, in higher plants the role of selenium is still unclear. The present investigation was carried out to study the response of wheat plants to selenium application in presence of humic acid under salt conditions, the study included evaluation for the impact of this response on productivity of wheat plants. To achieve this goal two germination experiments were performed in order to choose and define the best concentrations of selenium and humic aid.
Wheat grains were germinated on different concentrations from sodium selenite (5µm/l- 10µm/l- 20 µm/l- 40 µm/l- 80 µm/l) and humic acid (0.5gm/1000ml -1 gm/1000ml -2gm /1000ml- 1gm/100 ml -5gm/100 ml -10gm/100 ml -20gm/100 ml - 40gm/100 ml) after soaking the grains for 6 hours to select the most suitable concentrations. Wheat grains were then grown on sandy soil, under different concentrations from mixtures consisting of the best suitable concentrations of both selenium and humic acid under Salt Stress conditions. Based on the results of above preliminary experiments, field experiments were using performed saline soil.
Results showed that soaked wheat grains in different concentrations of mixtures of selenium and humic acid led to increases the percentage of germination as well as length both shoot and root along with their dry matter contents, were also favored total soluble sugars.
Results also revealed that used mixtures of selenium and humic acid in saline soil led to increases resistance of plants to salinity conditions, therefore decreasing the content of proline compared to control, in case of wheat grains, the treatments also improved the proportion of protein and selenium compared to the control.