Chitosan-Enclosed Menadione Sodium Bisulfite as an Environmentally Friendly Alternative to Enhance Biostimulant Properties against Drought

Biostimulants are an interesting strategy to increase
crop tolerance
to water deficits, and there is an extensive bibliography on them.
However, most of them need to be treated continuously to increase
protection throughout the growth cycle. In this context, we chose
menadione sodium bisulfite, whose protective effect against water
deficit has been previously demonstrated but only for a short period
of time. Nanoencapsulation seems to be an interesting way to improve
the properties of biostimulants. Our results show that menadione sodium
bisulfite (MSB) encapsulated in chitosan/tripolyphosphate nanoparticles
can increase the system’s tolerance against an imposed water
deficit and delay the need for retreatment by at least 1 week, accelerating
plant recovery after rehydration. This highlights the positive properties
of nanoencapsulation and shows how a simple encapsulation process
can significantly improve the biostimulant protective properties,
opening up new possibilities to be explored under field conditions
to cope with water-deficit stress.