Microneedle technology advanced as a means of noninvasive drug administration for humans is being A tomato plant injected by an array of phytoinjectors. Scale bar: 1 mm. Source: Yunteng Cao et al.extended to disease prevention in the botanical realm. MIT researchers are adapting the drug delivery approach to the development of phytoinjectors designed to stem the spread of various plant pathogens.

An array of microneedles is synthesized with a hydrophilic silk-based biomaterial to deliver nutrients, drugs or other agents to roots, stems or other parts of a plant. Diseases impacting leaves or stems can be treated with pesticide sprays, but pathogens attacking plant vasculature tissues are not well controlled by such chemical treatment. The phytoinjectors can perform this pest control mission by target the phloem circulating through a plant’s tissues, which could carry an antibacterial compound down into the roots.

The microneedle system described in Advanced Science was tested on tomato and tobacco plants in the laboratory. The researchers were able to observe injected fluorescent molecules traveling through the plants from roots to leaves. With continued development, the phytoinjectors could be deployed to deliver micronutrients as well as pesticides, or to help bioengineer disease-resistant varieties of important crop plants.