Influence of Soil Moisture and Salinity on the Carbon Dioxide Emission and Water Consumption during Germination of Cereal Seeds

Resumo

The influence of moisture and salinity of quartz sand on activation of the CO₂ emission and water consumption by seeds of spring wheat (Triticum), winter rye (Secále cereále), triticale (Triticosecale), and spring barley (Hórdeum) treated by a stimulant was studied under conditions of a model experiment. It was found that the seeds treated with a stimulant get advantages in the development upon a decrease in the water content of quartz sand. However, in the case of sand salinization, stimulant application did not lead to acceleration of seed development. The deficiency of moisture in saline sand also resulted in the increase of stimulant application efficiency. It was supposed that optimum moisture contents of quartz sand for seed germination and for the development of endophytic microorganisms do not coincide: active development of endophytic microorganisms stimulating seed development began under a lower moisture in comparison with that of the active seed development. Thus, active development of endophytic microorganisms upon the low moisture content mitigates the deceleration of seed development in the case of water deficiency. Hence, application of the microbial stimulant for seeds should be efficient in the cases, when germination of seeds proceeds under conditions of possible moisture deficiency, i.e., in the regions, where early spring droughts are frequent.