APBN New Site

APBN Developing Site

New Sensors Can Rapidly Detect Plant Hormones and Herbicide Resistance

Researchers have found a way to use corona phase molecular recognition nanosensors to detect synthetic plant auxins in real-time, potentially revolutionising screening methods for herbicide resistance in urban farms.

In the farming industry, two synthetic plant hormones, 1-naphthalene acetic acid (NAA) and 2,4-dichlorophenoxyacetic acid (2,4-D), are widely used to regulate plant growth and act as a herbicide respectively. This is because both NAA and 2,4-D are chemically more stable and potent than most endogenous auxins. Currently, biological assays and immunochemical methods are used to detect the presence of these hormones. However, such techniques usually damage plants and cannot provide real-time monitoring in planta.

In light of these limitations, scientists from the Singapore-MIT Alliance for Research and Technology, Massachusetts Institute of Technology (MIT)’s research enterprise in Singapore, Temasek Life Sciences Laboratory, and Nanyang Technological University (NTU) have come together to find a solution. Drawing inspiration from the concept of corona phase molecular recognition (CoPhMoRe), they developed safe and efficient nanosensors that can rapidly test for synthetic auxin plant hormones and plants’ response to herbicides. Their novel technology shows immense potential to transform agricultural production and our current understanding of plant growth.

To determine the efficacy of their creation, the researchers tested both the NAA and 2,4-D sensors on a number of crops including pak choi, spinach, and rice across various planting mediums like soil, hydroponic, and plant tissue culture. Their experiments revealed that the nanosensors could swiftly detect the auxins in living plants without posing any harm and allow for real-time monitoring of plants. With these results, experts are hopeful that the new tools can advance our knowledge about hormone distribution and signalling, as well as facilitate more efficient use of synthetic auxins in agriculture.

“Our CoPhMoRe technique has previously been used to detect compounds such as hydrogen peroxide and heavy-metal pollutants like arsenic – but this is the first successful case of CoPhMoRe sensors developed for detecting plant phytohormones that regulate plant growth and physiology, such as sprays to prevent premature flowering and dropping of fruits,” explained co-lead Principal Investigator Professor Michael Strano and Carbon P. Dubbs Professor of Chemical Engineering at MIT. “This technology can replace current state-of-the-art sensing methods which are laborious, destructive, and unsafe.”

In addition to the primary goal of detecting hormones, it was also discovered that their 2,4-D nanosensor could also detect herbicide susceptibility. This could enable farmers and agricultural scientists to quickly determine how vulnerable or resistant different plants are to herbicides without having to monitor crop or weed growth over days. Moreover, researchers could also gain a better understanding of plant growth dynamics and herbicide resistance. According to Principal Investigator Dr. Rajani Sarojam from Temasek Life Sciences Laboratory, “This could be incredibly beneficial in revealing the mechanism behind how 2,4-D works within plants and why crops develop herbicide resistance.”

In terms of applying the nanosensors in agricultural settings, NTU Professor Mary Chan-Park Bee Eng believes that the technology can be easily adapted for commercial setups since they use very low-cost electronics. In particular, she is hopeful because “using nanosensors for in planta detection eliminates the need for extensive extraction and purification processes.” Therefore, the technology would greatly save both time and money. Given these findings, the team is optimistic that their research can pave the way for future developments of real-time nanosensors for other dynamic plant hormones and metabolites. [APBN]

Source: Singapore-MIT Alliance for Research and Technology (SMART)