Link to home

Can nanoparticles enhance disease resistance through mineral nutrition

Nubia Zuverza-Mena: Connecticut Agric. Exp. Stn

<div>Soil-borne pathogens cause over 20% losses in crop yields per year. Mineral elements, such as Cu, Mn, and Zn, can activate enzymes to initiate defense mechanisms against disease. However, these plant nutrients are often not readily available at the root level in sufficient quantities to fight fungal infection. An alternate method to fungicides and other disease management approaches is to supply plants with nutrients of a nano-size that may be basipetally translocated. Metal oxide nanoparticles were sprayed at 500 - 1,000 µg/ml onto tomato, eggplant, and watermelon leaves. Plants were then grown in potting soils infested with Fusarium or Verticillium pathogens in the field and greenhouse. In the greenhouse, disease progress due to Fusarium (AUDPC) was reduced by 31 %, 28 %, or 28 % in tomato plants treated with nanoparticles (NPs) of CuO, Mn<sub>2</sub>O<sub>3</sub>, or ZnO, respectively. In eggplants, CuO NPs increased the fresh weight by 64 %, reduced the verticillium wilt AUDPC by 69 % and the amount of Cu in roots incremented by 32 %.In the field, treatment with CuO NPs and bulk-size Mn<sub>2</sub>O<sub>3</sub> increased the tomato yield by ~ 30 %; while the eggplant yield was increased 34 % and 41 % in plants treated with CuO NPs and ZnSO<sub>4</sub> salt. Watermelon plants treated with CuO NPs had between 39-53% increases in yield. These findings show that supplying nano-nutrients though foliar application can potentially reduce root diseases and increase yield.</div>