Nano-hives for plant stimuli controlled targeted iron fertilizer application

Abstract

In spite of iron being an abundant element present in soil, often crops show iron deficiency, because it is not present in phyto-available forms. External application is also not successful, because of soil carbonate/bicarbonate ions assisted conversion into unavailable oxy hydroxyl forms. Here the chitosan coating on iron powder loaded mesoporous silica have been found to control the above undesired soil reaction. The coating acts as gate, which close the pores in the presence of carbonate ions to keeps the iron in phyto-available forms, whereas open the pores in the presence of the uptake proton signal from the roots. This phenomenon of excellent control in the nutrient supply to plant is a complementary effect of the pH responsive chitosan and the mesoporous channel. Because in the absence of either of the component, the performance is reduced. In the tomato plant experiment, the ferric chelate reductase activity, an iron deficiency parameter, is reduced by ~20% in plants treated with FeSO4@MS@CH compared to the one treated with FeSO4@MS.