In recent years, nanobubbles (NBs) as a novel technology have attracted people’s great concern in both agricultural and engineering fields. It has been proved that the water contain-ing NBs can accelerate the growth of plants, shellfish and yeast. Up to now, the explanation has not theoretically been given for these new scientific findings, especially to growth promo-tion and sterilization. On the other hand it is known that reactive oxygen species (ROS) play a vital role in growth by facilitating the required cell wall loosening for cell elongation. In our latest research we’ve reported that the water containing NBs can produce hydroxyl radicals in the water. Here, we’ve reported a direct evidence for the positive effect of NBs on the ROS production inside barley seeds.
The mechanism of NBs’ physiological activity promotion was investigated with germination tests and nitroblue tetrazolium (NBT) staining method. The germination rates of barley seeds dipped in water containing NBs were more than 10 percentage points greater than those of the seeds dipped in distilled water with the same concentration of dissolved oxygen (DO). 5 geminated seeds in each group were incubated in 1 mM nitroblue tetrazolium (NBT) in 10mM Tris-HCl buffer (pH 7.34) at room temperature for 30 minutes. Then the seeds were cut into 100μm slices with a cutting machine. ROS can be visualized as deposits of dark-blue insolu-ble formazan compound using microscope spectrophotometer.