Optimization, characterization and application of chitooligosaccharide-urea conjugate for wheat seed priming: A...

The present study deals with the preparation of chitooligosaccharide (COS), its conjunction with urea, and its priming effect on wheat grains. Employing central composite rotatable design (CCRD) of response surface methodology (RSM) to optimize conditions for COS production resulted in COS with a reducing sugar: 4.14 mg GAH/ml and an average particle size: 232 nm. FTIR, FESEM and XRD validated its formation. The COS displayed exceptional antioxidant properties via. DPPH (IC₅₀: 7.74 mg/ml), ABTS (IC₅₀: 0.147 mg/ml), MCA (IC₅₀: 0.329 mg/ml) and TAA (AO_0.5: 1.76 mg/ml). It was then dopped with urea, and FTIR and NMR detailed the interaction between COS and urea, primarily owing to hydrogen bonds. On studying the effect of priming of wheat grains, an increase of 41.5 % and 22.62 % in shoot and root length of wheat seedlings was noticed with COS-urea (25-50 ppm). Fresh weight, dry weight, SVI-I and SVI-II also detailed the maximum positive trend with COS-urea followed by the maximum utilization of starch and protein. This study provides a new perspective on the application of COS-urea for enhancing the germination potential of wheat, and also for its potential use as a foliar spray, contributing towards sustainable agriculture and the environment.