A new study has found out how we could grow more crops with fewer fertilizers

New research identifies nearly 300 species of microorganisms that grow together with common Asian vegetables.

For vegetables to grow well, it is not enough to just give them sunlight and water; They need a whole community of microorganisms to help them grow healthily.

The finding is the first step towards helping high-tech urban farmers produce more crops with less chemical fertilizers.

Currently, what little is known in this field of research has been garnered mostly from standard plant species used in experiments, and they are not vegetables. To address this gap, the team from the National University of Singapore collaborated with a commercial urban farm in Singapore.

They obtained soil samples, as well as both the seedlings and mature plants of three common Asian vegetables: choy sum, kai lan, and bayam (also called Chinese flowering cabbage, Chinese broccoli/Chinese kale, and Chinese spinach, respectively). The team extracted the microbes and their genetic material in the soil and on the plants for analysis.

“Green leafy vegetables are nutrient-dense and packed with bioactive compounds known for promoting human health,” says study leader Sanjay Swarup, associate professor in the biological sciences department.

“These leafy greens are short-cycle crops, suitable for adoption in various farming formats. Focusing our research priorities on this food group will address food and nutritional security and cater to both quantity and quality aspects of food production.”

The researchers sequenced the genetic material in the samples using a technique called metagenomics. It uses computational methods to analyze the diversity and characteristics of the genetic material without having to isolate and culture individual species of microorganisms. This method gave them a comprehensive picture of the microbial community in less time and with less effort.

Using a supercomputer, the researchers identified almost 300 species of bacteria and a group of single-celled, bacteria-like organisms known as archaea. From the data, they found that the microbes could potentially benefit the vegetables by providing nutrients, stimulating growth, and suppressing pathogens. The findings of the four-year study appear in the journal Scientific Data.

“We have seen how food supply chains are adversely impacted by the COVID-19 pandemic. Therefore, we need urgent reformative actions to build greater food resilience and security. Through this study, we are taking the first step towards building innovative solutions to boost local production in a highly sustainable manner,” says Pavagadhi Shruti, the senior manager of the team who led the field sampling and laboratory work.

Building upon their research, the team will be conducting detailed studies to identify the best microbial strains for enhancing crop production. They also hope their findings will encourage further research to understand how micro-organisms enhance crop growth and find new ways to cultivate these micro-organisms.

Research fellow Aditya Bandla led the computational work for the study.