A Toxic, Invasive Weed Discovered to be Useful as an Organic Fertiliser

According to a new study, the toxic, invasive herb Ageratum conyzoides, also known as billy goat weed, can be bio-converted into nutrient-rich compost for crop cultivation. The study, which was published in the journal Biomass Conversion and Biorefinery in March, discovered that the compost was environmentally safe and ideal for use as a soil conditioner to improve farmlands.

Findings of Study:

According to Krishna Chaitanya Maturi, an author of the study and researcher at the Indian Institute of Technology (IIT) Guwahati, the negative impact of A. conyzoides weeds is well documented, particularly in degrading soil quality by reducing useful soil organisms. The invasive weed, also known as billy goat weed and chickweed, is native to South America.

"As a result of the presence of toxic allelochemicals such as stigmasterol, demethoxy-ageratochromene, and caryophyllene in A. conyzoides, it is harmful to neighbouring crops." "It also disrupts various aboriginal plant cultures in various ecological regions," Maturi explains to SciDev.Net.

According to Ajay S. Kalamdhad, co-author and professor of Environmental Engineering at IIT, the study's goal was to create a non-toxic product by biologically treating the plant and blending it with inoculums (a combination of microorganisms and organic matter) and bulking agents in a rotary drum composter.

"The composter was capable of increasing nutritional parameters like nitrogen, phosphorus, and potassium while decreasing lignin, hemicelluloses, and cellulose," Kalamdhad says. "The use of A. conyzoides for in-vessel composting is a novel approach to obtaining a value-added product that is rarely reported in other management technologies."

Kalamdhad claims that statistical analysis revealed a close relationship between biodegradation and nutritional products after composting. "As a result, the study suggests that A. conyzoides compost can be used in a variety of farming applications that require a nutrient-rich, non-toxic, environmentally acceptable product," he continued.

According to an FAO paper, the value of A. conyzoides in increasing soil fertility is part of indigenous knowledge among farmers in Arunachal Pradesh's mid-hills. According to the paper, farmers in Arunachal Pradesh believe the plant can be used to increase rice grain yields by improving soil chemical properties and fertility.

K.C. Jisha, an assistant professor at Kerala's Muslim Education Society College who was not involved in the study, believes the findings will be useful to agro-industry policymakers seeking effective weed management strategies. "A. conyzoides compost can be used as a replacement for chemical fertilizers," she tells SciDev.Net.

"Plants in the [Asteraceae] family are rich in bioactive compounds like polyphenols, terpenoids, and flavonoids, and their essential oils have long been used [in traditional medicines such as for skin diseases and diarrhoea," says R. Seema Devi, a researcher specializing in the phytochemistry of aromatic medicinal herbs and assistant professor at the N.S.S. College, Manjeri, Kerala.

"A. conyzoides is an annual herb used to treat skin diseases, diarrhoea, and gynaecological issues in folk and ethnobotanical medicine. It has anti-microbial, anti-inflammatory, anti-malarial, and other properties, according to research."

(Source: Phys.org)