Nano-enhanced storage of American cotton using metal-oxide nanoparticles for improving seed quality traits

Cotton seeds have poorer germination than other crops because of their high sensitivity towards insect pests and other biotic and abiotic stresses during the germination process. In the present study, inorganic bulk and nano nutrients of zinc oxide (ZnO) and titanium oxide (TiO₂) nanoparticles were synthesized using the chemical reduction method and invigourated with cotton seeds. The characterization of nanoparticles was done by FESEM, HRTEM, UV/Vis analysis and FTIR. The delinted and fuzzy seeds of two American cotton varieties (H 1300 and H 1098-i) were nano-primed for 10 h with zinc oxide nanoparticles (ZnONPs) @ 400 ppm and titanium dioxide nanoparticles (TiO₂NPs) @ 100 ppm. After nanoparticle invigouration, the seeds were analyzed for various parameters at different intervals (0 months, 3 months, 6 months, 9 months and 12 months) such as germination percentage, seedling length, seedling dry weight, electrical conductivity, dehydrogenase activity, antioxidant enzyme activity. The results indicated that that different storage periods and nanopriming treatments had significant effects on all seed quality parameters except the effect of nanopriming treatments on germination percentage (excluding delinted seeds of H 1098-i). It is also revealed that the interaction effect of nanopriming treatment and storage period was non-significant on all parameters except EC. Maximum reduction in seed quality parameters was observed in control treatment and minimum was found when seeds were nanoprimed with ZnONPs @ 400 ppm. The differences in the response for both NPs can be attributed to their surface charge, and concentration used. Overall, ZnONPs and TiO₂NPs could hold seed quality and vigour during the storage of cotton seeds of American varieties (H 1300 and H 1098-i).