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The Hidden Helpers Living Inside the Plants at Molelwane Farm
(North-West University (South Africa), 2026) Babalola, Olubukola Oluranti
At Molelwane Farm in Mafikeng, South Africa, plants were growing quietly in the field. To the farmer, a plant is something visible: leaves reaching for sunlight, roots holding it in the soil, and eventually a harvest. But what if some of the plant's most important helpers could not be seen at all? Inside healthy plants, scientists can find communities of microorganisms known as endophytes. These bacteria live within plant tissues without necessarily causing disease. Some can form beneficial relationships with their host plants and contribute to plant growth.
When the Rain Stops: A Farmer, Her Soybeans and the Invisible Helpers Beneath the Soil
(North-West University (South Africa), 2026) Babalola, Olubukola Oluranti
Some are bacteria called Rhizobium. Others are mycorrhizal fungi. They are too small to see, but they can become important partners of plants. The farmer may not know their names. She may never see them. But these organisms are quietly interacting with the roots of her soybean plants. This hidden relationship fascinated O. N. Igiehon and Olubukola O. Babalola. They wanted to know whether these microbial partners could help soybean plants when water became scarce. So they created drought-stress conditions and examined what happened when soybean plants were associated with Rhizobium and mycorrhizal fungal species. The result was striking. The microbial partners improved soybean yield under drought-stress conditions. For the farmer, this finding changes the way we think about the soil. Soil is not simply where a seed is planted. It is a living ecosystem. And a soybean plant does not necessarily have to face drought alone. Rhizobium bacteria can form beneficial associations with soybean roots and contribute to biological nitrogen fixation. Mycorrhizal fungi can form extensive networks associated with roots, helping plants access resources in the surrounding soil.
The Invisible Chemical Defenders of Bambara Groundnut
(North-West University (South Africa), 2026) Babalola, Olubukola Oluranti
Beneath the soil, where our eyes cannot see, plants live in a busy microbial world. The roots of Bambara groundnut-a hardy and nutritious African legume-are surrounded by countless bacteria. Some of these bacteria are more than passive neighbours. They can produce natural chemicals that influence other microorganisms living around the plant. But what exactly are these microscopic bacteria producing? That was the question explored by Caroline F. Ajilogba and Olubukola O. Babalola. The researchers collected rhizobacteria associated with Bambara groundnut and investigated the volatile organic compounds (VOCs) produced by these bacteria. VOCs are small chemical molecules that can evaporate easily and can act as powerful signals or biological weapons in the microbial world. Using gas chromatography-mass spectrometry (GC-MS), the scientists were able to identify the chemical compounds released by the bacteria. And then came an intriguing discovery. Some of these microbial chemicals demonstrated antibacterial activity. Think of the soil around a plant as a microscopic battlefield. Different microorganisms compete for space and nutrients. Some bacteria have evolved an elegant strategy: instead of physically fighting their competitors, they release chemical compounds that can inhibit the growth of other bacteria. The Bambara groundnut rhizobacteria appeared to possess some of these chemical abilities.
Periodic variation of anomalous cosmic ray oxygen during solar cycles 23 and 24
(Springer Nature, 2025) Kotzé, Pieter; Mursula, Kalevi
We investigate the evolution of the Rieger periodicity at 152 - 156 days, the 27-day synodic rotation period as well as the 13.5- and 9-day harmonic periodicities in anomalous cosmic ray (ACR) oxygen (O) fluxes at the energy range between 8 - 25 MeV/n observed by the Advanced Composition Explorer (ACE) satellite during Solar Cycles 23 and 24. The ACR oxygen flux data is analysed using the Lomb-Scargle periodogram and Morlet wavelet spectral analysis techniques. Daily mean oxygen fluxes during solar quiet times are used to identify how the ACR oxygen at different energies varies with the Rieger periodicity and the solar rotation periodicities in each year. This is the first investigation of the periodicity evolution of ACR oxygen ions. Previous investigations have mostly concentrated on the spectral behaviour of GCR particles during various solar cycles of opposite polarities, in particular the 27-day and 13.5-day periodicities. Our analysis revealed a significant temporal and energy dependence in the spectral behaviour of ACR oxygen during both cycles. An important finding of this investigation, not reported before in the literature, is the significant increase in the power of the different ACR oxygen periodicities during the minimum of Cycle 24/25 (characterised by a positive solar polarity) in comparison to the minimum of Cycle 23/34 (dominated by a negative solar polarity).
Mathematical modeling and numerical analysis of intermediate-temperature water (steam) electrolysis cell performances
(EDP Sciences, 2026) Grigoriev, Sergey; Kalinnikov, Alexander
A physicochemical model of an intermediate-temperature water (steam) electrolyzer based on a proton exchange membrane (PEM) was developed. The results of numerical modeling provide recommendations for membrane-electrode assembly (MEA) parameters based on the required electrolyzer operating conditions. Specifically, electrocatalytic layer thicknesses can be recommended to ensure high electrolyzer performance with optimal platinum metals content. The importance of sufficient ionomer in the electrocatalytic layers is demonstrated.