Chemical-radiation degradation of natural oligoamino-polysaccharides for agricultural application

The main objective of the research was to elaborate the method of degradation of natural aminopolysaccharides to obtain a product applicable as biospecimen in protection and stimulation of the plants growth. Depolymerization of chitosan can be carried out by radiation or chemical degradation combined with irradiation method. The efficiency of these methods was verified by viscometric analysis. The chemical-radiation method was much more appropriate from economical point of view. By application of this method it was possible to obtain product with lower crystalline phase content than initial one, what was proved by X-ray diffraction studies. Finally preliminary agricultural tests on spring rape seeds were performed. The results show that the biggest growth was observed for chitosan (molecular weight 47,000 Da) in concentration of 0.1 g/kg of seeds. The higher concentration did not affect plant's growth. The average growth over-ground plant parts was about 16–22%, diameter of roots was about 11–13%, and mass of roots was about 51–65% higher in comparison to the control.