Researchers discover a new way for the early detection of shade avoidance syndrome in plants

Reviewed by Emily Henderson, B.Sc.November 25, 2020

Researchers from the Disruptive & Sustainable Technologies for Agricultural Precision (DiSTAP) Interdisciplinary Research Group (IRG) of Singapore-MIT Alliance for Research and Technology (SMART), the research firm of MIT in Singapore and Temasek Life Sciences Laboratory (TLL) have discovered a way to use Raman spectroscopy for the early detection of shadow avoidance syndrome (SAS) in plants. The discovery can help farmers with timely action against SAS, leading to improved plant health and crop yield.

SAS is an adaptive response and an irreversible phenomenon, in which plants reach more light to overcome shade conditions. It is commonly seen in plants experiencing vegetative shade which is detrimental to plant health, as it leads to a number of problems including hindering leaf development, early flowering, and weakening of the plant’s structure and immune system.

Therefore, early detection of SAS is crucial for sustainable agriculture and better crop yield. However, existing methods for detecting SAS in implants are limited to observing structural changes, making SAS difficult to detect early.

In a paper entitled “Rapid response of metabolites in leaf lamina and petiole as a marker for shadow avoidance syndrome” published in the prestigious journal Plant methods, SMART DiSTAP and TLL scientists explain their new way of detecting SAS early on, allowing farmers to intervene in time to prevent the irreversible effects of SAS. The team built a tabletop Raman spectroscopy instrument that enables measurement of carotenoid levels in plants, which can indicate whether a plant has SAS.

Our experiments with Raman spectroscopy found a decrease in the carotenoid content of plants that have SAS. While plants with longer shade exposure developed more severe SAS, these morphological changes were only seen after one to three days. However, the changes in the intensity of the carotenoid peaks were detected much earlier, starting with just four hours of treatment in the shade. “

Dr Gajendra Pratap Singh, co-first author of the article and Scientific Director and Principal Investigator at DiSTAP

Using Raman spectroscopy, scientists are able to non-destructively measure the carotenoid content in plant leaves and have discovered its correlation with the severity of SAS and as a peak biomarker for early diagnosis. This reduces the time it takes to detect SAS from days to hours. The method can also be used to detect SAS in plants due to high density plantations and can be particularly useful for improving urban farming practices.

“We conducted our experiments on a number of edible plants, including frequently consumed Asian vegetables such as Kai Lan and Choy Sum,” said Benny Jian Rong Sng, co-first author of the paper and PhD student of Dr. In-Cheol Jang at the TLL and Department of Biological Sciences, National University of Singapore. “Our results showed that Raman spectroscopy can be used to detect SAS, induced by shade and high density plantations. Regardless of the food crop, this technology can be applied to improve agriculture and to meet nutritional needs. of the current growing populations. “

Dr In-Cheol Jang, principal investigator at TLL and DiSTAP, who led the project, said the new discovery can do a lot to help farmers improve urban farming practices. “We look forward to helping urban farmers achieve higher yields by detecting SAS in shorter time periods. By adopting scalable and precision farming technologies such as Raman spectroscopy-enabled sensors, we can better position cities like Singapore to grow more produce with fewer resources, achieving the desired nutritional profiles for global food security “.