Effects of Exogenous Diluted Raw Clover Honey on Drought Tolerance in Arabidopsis thaliana

Blessing Awogbamila, Guddi Brahmbhatt, Jenna Brodnyan, Paula Khoiniha, Rosemarie Arroyo-Martinez

Department of Biology, Rutgers University, Camden NJ 08102


Globally, drought is a major agricultural and economic problem, specifically due to its effects on crop yield. Effective and economical strategies to mitigate drought stress in agricultural plants must be developed as drought continues to escalate in both frequency and intensity. Substances known as biostimulants have been studied for their agricultural outputs, as they are capable of increasing nutrient uptake in plants, enhancing crop quality traits, and increasing tolerance of abiotic stress, such as drought. Currently, commercially produced biostimulants are expensive. A cost-effective alternative to commercial biostimulants is honey, which is considered a natural biostimulant by-product of sustainable agriculture. Honey has been shown to be beneficial when sprayed directly onto the leaves (i.e., the foliar method) of crops that are experiencing abiotic stress, such as drought.  However, the precise study of drought mitigation using diluted honey has not been studied using the dicot model plant Arabidopsis thaliana or by using the subirrigation method. In this study, we hypothesized that exogenous diluted honey reduces the effects of drought stress on A. thaliana, and its beneficial effects are due to the biostimulants in honey. To test this hypothesis, plants exposed to drought and normal conditions were administered various concentrations of honey, phosphate solution, and water. Seed volume and biomass, which are measures of plant yield, were evaluated and recorded. We found that diluted honey reduced crop lifespan while maintaining or increasing crop yield when applied by the subirrigation method to plants under both normal and drought conditions. Additionally, diluted honey increased seed size in plants subjected to drought stress, but it does not affect the seed volume of plants under normal and drought conditions. Given that the diluted honey treatments produced the same biomass in less time than the control groups under drought stress, our results supported the view that application of diluted honey by subirrigation may prove to be a sustainable, naturally available, and economically advantageous agricultural practice to overcome drought stress.