Could Fitbit’s newest brand ambassador be a Brazilian soy plant?
Smartwatches and other wearable technology are becoming increasingly sophisticated, so much so that these devices are no longer amenities exclusive to humans. For several years, scientists have been investigating how these wearable devices that monitor our wellbeing could be adapted to track plant health in real-time and aid cultivation choices. Agriculture and crops are essential to both our food security and our economy. However, efficient and sustainable farming practices (i.e. large yield with small environmental consequences) are difficult to achieve when several factors harm plant health.1 These include the salt levels of water, ultraviolet radiation, ozone exposure, and toxic agents, but the major forces are pests, diseases, and drought stress, resulting in significant yield losses.1,2,3 There is an urgent need for plant wearables which can monitor growth, loss of water content in leaves, climate, and any other relevant indicators which can assist in gauging plant wellness.1,2
When researchers began designing wearables for plants, many obstacles had to be considered. The devices had to be able to attach to the plant, flexible enough to match the plant’s motion, built to withstand deformation and fluctuating climate conditions, and unobtrusive to the plant’s natural processes, all while reporting accurate data.1 One of the biggest challenges had to do with electrode sensors in the wearables. These sensors had to be placed on the leaves to measure the plants’ signals, similarly to electrode patches which monitor heart activity in humans when placed on the chest. However, selecting electrodes which were compatible to the plants’ biological processes, as well as attaching them to the plant’s leaves, proved to be very difficult. Leaves’ irregular shape, hairy surface structures, and shrivelling all caused poor adhesion between the electrode and the leaves, leading to faulty data collection.1,3 Additionally, electrodes could disrupt photosynthesis in plants by blocking out light, which seriously harms plant health instead of monitoring it.1 Nevertheless, a wearable for soy plants was successfully developed just last year. The team consisted of researchers at the Campus Bio-Medico University of Rome, who proposed the methods, and technologists at the Brazilian Nanotechnology National Laboratory, who created the wearable to monitor water loss and indirectly assess exposure to pests and toxic agents.1,2,3
Composed of a stretchy, snake-shaped nickel electrode structure, this wearable can harmlessly attach to soy leaves with regular adhesive tape.1 The decreasing water content is recorded and the data is shared to a smartphone via Bluetooth connection.1 Finally, machine learning converts the data into user-friendly figures which can be more easily interpreted.1,3 These devices are known as “stand-alone Ni structures” or SANSs (Ni is the chemical symbol for nickel). Nickel was proven to be a highly effective material through tests that found the plants adhered best to the nickel in different temperatures and wind conditions.1 Additional tests found the nickel electrode was able to measure water loss accurately and effectively.
Although the SANS is a step towards more sustainable agriculture and crop management, it is not an exhaustive solution. Further testing of the SANS in extreme climate conditions and for various plant species will allow for greater and more suitable farming applications. Scientists are also looking into paper-based wearables which, despite less efficiency in terms of monitoring sensitivity, have benefits with respect to green chemistry: paper is a cheaper, widely accessible, and biodegradable material, and also generates less waste when manufactured.1
With future experimentation, perhaps plant wearables will become as widespread as smartwatches, giving all plant growers—professional and novice—the opportunity to better care for their plants.
1. Barbosa JA, Freitas VMS, Vidotto LHB, Schleder GR, de Oliveira RAG, da Rocha JF, Kubota LT, Vieira LCS,
Tolentino HCN, Neckel IT, et al. Biocompatible wearable electrodes on leaves toward the on-site monitoring of water loss from plants. ACS Appl. Mater. Interfaces [accessed 2023 Oct 11]; Vol.14: p.22989-23001. Doi: 10.1021/acsami.2c02943
2. Lo Presti D, Cimini S, Massaroni C, D’Amato R, Caponero MA, De Gara L, Schena E. Plant wearable
sensors based on FBG technology for growth and microclimate monitoring. Sensors [accessed 2023 Oct 11]; Vol.21: p. 1-16. Doi: 10.3390/s21196327
3. A new wearable technology — for plants by American Chemical Society. Headline Science2022 May 4, 2:32 [accessed 2023 Oct 3]. https://www.youtube.com/watch?v=i864_c0fvVg