The effect of terahertz frequency range electromagnetic radiation on agricultural crops

The results are put forward for the study of terahertz frequency range radiation effect on seeds of maize of Volgogradskaya and PS (Purpurnaya Saratovskaya) population, sorghum of Volzhskiy 51 and Melodia cultivars, Sudan grass (Sorghum sudanense) and wheat of Saratovskaya zolotistaya cultivar.

Dry seeds were exposed to electromagnetic radiation (EMR). Control sets of seeds were kept outside of EMR exposure under otherwise similar conditions. After that the seeds were soaked in water for 20 hours and couched in Petri dishes on absorbent paper at 27 ºС.

In the experiments a millimeter wave generator of VZRIP G4-161 class with working frequency range of 129.200-142.800 GHz was used. The used exposure frequency corresponded to one of the molecular spectrum lines of atmosphere oxygen absorption at 129±0.2GHz. Exposure time was 30 minutes. Power density at seed level was 10µW/cm2.

Seed germinating and seedling morphological parameters were noted to evaluate electromagnetic radiation effect on plants.

It was revealed that exposure of the investigated crops to EMR at the frequency of one of oxygen spectrum lines has substantial stimulating effect on seed germinating, with the exception of Melodia cultivar sorghum where germination index was lower by 8% than in the control group. The stimulating effect of EMR manifested itself vividly in the increase of all the maize seed parameters under study. EMR had either inhibitory effect on seedling morphological parameters and mitotic activity of root apical meristems of other investigated crops - e.g. growth of maize seedlings of PS line slowed 5.7-fold, and that of Saratovskaya zolotistaya wheat slowed 4.7-fold - or had no substantial effect on the parameters under study (Sudan grass, Volzhskiy sorghum and Melodia sorghum).