A North-West University (NWU) female academic, Dr Bongiwe Dhlamini-Zungu, has made a remarkable scientific discovery with the potential to increase the maize harvest in South Africa (SA). Maize is the staple food source for most sub-Saharan countries including SA.
Indigenous African Herb
Dr Dhlamini-Zungu says maize seeds germinate quickly and become thriving seedlings when combined with fertiliser made from nano-particles, extracted from a popular and indigenous African herb, impepho. The strong herb (helichrysum odoratissimum) is also known as kooigoed or African sage. The title of her PhD study was: “Engineered polysaccharide-based nanoparticles as hybrid fertilizer for efficient plant nutrition and stress tolerance”.
- The herb is steeped in rich African tradition and spirituality and has been used for centuries for its medicinal and spiritual properties. It is largely believed to protect and cleanse body and soul. People use the herb to connect, communicate and mediate with the ancestors. The parts of the herb commonly used are the leaves, stems and flowers and sometimes the roots. Some of the herb’s medicinal uses include antiseptic and insecticidal, as well as anti-microbial and anti-inflammatory and pain-relieving (analgesic) agents.
Nano-Engineered Fertiliser
Dr Dhlamini-Zungu, who has recently obtained a PhD in chemistry from the NWU, harnessed the potency of the herb for the greater good of the public. Her study focused on developing an environmentally-friendly and nano-engineered fertiliser, designed to enhance crop yields with reduced inputs. Using extracts and ingredients from impepho, she created zinc and iron oxide polysaccharide-based nano-particles. Her study showed that the African sage herb helped to make these nano-particles by acting as a reducer and providing oxygen. Through the study she aims to address food security and promote environmental sustainability.
Nano-Priming Agents
Dr Dhlamini-Zungu says the nano-particles were covered with a chitosan biopolymer, an eco-friendly substance made from the outer skeleton of shellfish. This allows the nano-particles to release nutrients slowly over time; ensuring maize plants receive a steady supply of nutrients. “The innovative aspect of my research was the application of these zinc oxide and chitosan-based nanoparticles as nano-priming agents on maize seeds. The results were remarkable: seed germination and early seedling growth of maize were significantly improved, even under salinity stress conditions. This demonstrated the potential of nanotechnology in enhancing crop resilience and productivity in challenging environmental conditions,” she explained.
Reducing Environmental Footprint
Her findings represent the latest and innovative applications in agriculture, geared towards promoting sustainability by using indigenous plants. Dr Dhlamini-Zungu taps into the unique properties of nano-particles with her research providing imaginative solutions to reduce the negative impact of certain agricultural practices. In addition, her research is in line with global efforts, particularly some of the UN’s Sustainable Development Goals (SDG’s) to promote sustainable agricultural practices and systems.
Inspiring Academic Journey
Dr Dhlamini-Zungu says her successful academic journey is the result of sheer hard work and patience. She started off as a research assistant at the NWU with the nanotechnology group in 2016. She was also a student laboratory assistant of the Chemistry subject group from 2017 to 2022 and has proven herself to be a top achiever: she was a Three-Minute Thesis (3MT) institutional second runner-up and a national 3MT winner in 2022. The title of her PhD study was: “Engineered polysaccharide-based nanoparticles as hybrid fertilizer for efficient plant nutrition and stress tolerance”.
To date her PhD research has resulted in two published articles – “Nano-engineering metal-based fertilizers using biopolymers: An innovative strategy for a more sustainable agriculture” in 2022, and “Zn-nutrients-loaded chitosan nano-composites and their efficacy as nano-priming agents for maize (Zea mays) seeds” in 2023.
