Gibberellin plant hormones are detectable and distinguishable by nanotube sensors.

 

The continued study of gibberellins could lead to further breakthroughs in agricultural science and have implications for food security. Credits: Photo courtesy of SMART.

 

Due to their similar chemical structures, gibberellins (GAs), a family of phytohormones that are crucial for plant growth, can be difficult to distinguish. Single-walled carbon nanotubes (SWNTs) with different corona phases that preferentially bind to bioactive GAs, GA3, and GA4 are created and manufactured by MIT researchers. This causes variations in fluorescence intensity in the near-infrared spectrum (NIR).

The Disruptive and Sustainable Technologies for Agricultural Precision (DiSTAP) initiative seeks to transform the methods used to identify, track, engineer, and translate plant biosynthetic pathways in order to satisfy the world's demand for food and nutrients. Researchers from MIT, Temasek Life Sciences Laboratory, NTU, and NUS are working together to create new instruments for constantly monitoring crucial plant hormones and metabolites.

Researchers from DiSTAP have created the first nanosensor for identifying gibberellins (GAs). The nanosensors, which are nondestructive and have been effectively tested in living plants, differ from conventional collection techniques. They could revolutionise plant biotechnology and agriculture by providing farmers with a useful instrument to increase yield.

 

For the purpose of identifying and detecting two plant hormones, GA3 and GA4, researchers created near-infrared glowing carbon nanotube sensors. These hormones, which are diterpenoid phytohormones made by plants, are believed to have contributed to the 1960s "green revolution," which prevented starvation and saved lives. Additional research on gibberellins might result in other innovations in crop science and have effects on food security.

Soil salinity increases as a result of climate change, global warming, and increasing sea levels, which inhibits GA biosynthesis and promotes GA metabolism. When used in the field, new nanosensors developed by SMART researchers enable the early study of GA dynamics in living plants under salt stress, enabling producers to make early interventions.

 

New sensors that can sense GA kinetics in the roots of model and non-model plant species as well as GA accumulation during lateral root emergence have been made possible thanks to Professor Michael Strano's CoPhMoRe concept. A new coupled Raman/near-infrared fluorimeter that allows for the self-referencing of nanosensor near-infrared fluorescence with its Raman G-band has been developed to make this feasible.

The reversible GA nanosensors observed reduced endogenous GA levels in plants under salinity stress as well as increased endogenous GA levels in mutant plants producing greater amounts of GA20ox1. After just six hours of exposure to salinity stress, lettuce growth was badly stunted and its GA levels dropped, proving its usefulness as a salinity stress indicator after ten days.

Co-corresponding author Strano, the DiSTAP co-lead principal scientist and Carbon P. Dubbs Professor of Chemical Engineering at MIT, said, "With our CoPhMoRe technique, we can make nanoparticles that behave like natural antibodies in that they can recognise and lock onto specific molecules. However, they are frequently much more secure than substitutes. This technique has been effective in helping us develop nanosensors for plant signals like hydrogen peroxide and heavy metal pollutants like arsenic in soil and plants. As demonstrated, the technique produces sensors for organic compounds such as synthetic auxin, a crucial plant hormone. This most recent discovery expands this achievement to the extremely challenging-to-identify gibberellin family of plant hormones.

The resulting technology, he continues, "offers a rapid, real-time, and in vivo way to monitor changes in GA levels in virtually any plant, and can replace current sensing methods that are time-consuming, damaging, species-specific, and much less effective."

" further than just a advance in factory stress discovery, we've also demonstrated a tackle invention in the form of a new coupled Raman/ NIR fluorimeter that enabled tone- referencing of SWNT detector luminescence with its Raman G- band, representing a major enhancement in the restatement of our nanosensing tool sets to the field," says Mervin Chun- Yi Ang, associate scientific director at DiSTAP andco-first author of the paper. Our detectors can soon be combined with low- cost electronics, transmittable optodes, or microneedle interfaces for artificial use, revolutionising how factory stress in food crops is screened for and eased while conceivably enhancing growth and yield.

the new sensors may still be used in a wide range of industrial uses. "GAs are known to regulate a wide range of plant development processes, from shoot, root, and flower development to seed germination and plant stress responses," explains Daisuke Urano, a principal investigator at the Temasek Life Sciences Laboratory and adjunct assistant professor at the National University of Singapore (NUS). These plant hormones are also marketed to growers and farmers as plant growth regulators to encourage plant growth and seed germination as a result of the commercialization of GAs. Our cutting-edge GA nanosensors may be used in the field to watch early signs of plant stress as well as by growers and farmers to monitor the uptake or metabolism of GA in their crops.

SMART and MIT carried out the statistical analysis of plant sensors, coupled Raman/near-infrared fluorimeter development and validation, and nanosensor design and development for this research. The planning, carrying out, and analysis of investigations pertaining to plants were done by the Temasek Life Sciences Laboratory.