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The dominance of a few staple crops (maize, rice, and wheat) in most agricultural systems hampers the application of interventions to improve food security and nutrition. Research and development attention has focused on improving the production and utilization of these crops, leaving other crops under‐researched and underutilized. Subsequently, there have been high malnutrition rates due to poor diet diversity, yet there are "opportunity crops" that remain under researched. The opportunity crops can unlock solutions to food insecurity, malnutrition, a lack of biodiversity, and indeed poor climate adaptation. The study explored diversification in agricultural systems to analyze whether reorientation of research investment to include under‐researched crops can increase nutrient gain and enhance dietary diversity. Research outputs benchmarked as the number of publications from three leading African universities, Nairobi, Pretoria, and Ghana, were related to crop diversity and nutrition of crops in five clusters: cereals, vegetables, legumes, roots and tubers, and nuts. The findings show that maize was the predominantly researched crop across the three institutions. Low research outputs were observed for pearl millet, finger millet, and yam across the three institutions: amaranth and nightshade (Pretoria), sweet potatoes (Pretoria and Ghana), Marama bean (Nairobi), and soya bean (Nairobi and Ghana). There was nutrient gain across all five clusters, particularly from under‐researched indigenous crops such as finger millet, amaranth, nightshade, yam, sweet potatoes, Marama bean, and soybean. Nutrient gain was contributed more by cereals and root and tuber crops from Pretoria, vegetables and nuts (Ghana), as well as legumes (Nairobi). The findings demonstrate that incorporating research on the least researched crops with successful integration of other research and development initiatives (policy and dissemination) can increase nutrition and improve dietary diversity. The nutrient gain will positively affect food security and nutrition, contributing to the achievement of Africa Agenda 2063, the United Nation's Sustainable Development Goals, and reducing food imports. The findings can inform research investment and decision across different institutions within the African continent. Research investment targeting crops such as finger millet, amaranthus, sweet potatoes, soya beans, and cashew nuts is needed considering the nutritional contribution, climate change adaptability, market potential, and biodiversity contribution. Further analysis should explore production, socio‐economic (marketability and income generation), and environmental gains (adaptive ability to climate change) for specific crops. The development of frameworks to guide the analysis of the nature and scope of factors affecting the contribution of these crops to food security and nutrition, as well as research on specific crops considering geographic distribution and institutional involvement, is also needed. [ABSTRACT FROM AUTHOR]

Abstract Background Ecosystem engineers facilitate habitat formation and enhance biodiversity, but when they become invasive, they present a critical threat to native communities because they can drastically alter the receiving habitat. Management of such species thus needs to be a priority, but the poorly resolved taxonomy of many ecosystem engineers represents a major obstacle to correctly identifying them as being either native or introduced. We address this dilemma by studying the sea squirt Pyura stolonifera, an important ecosystem engineer that dominates coastal communities particularly in the southern hemisphere. Using DNA sequence data from four independently evolving loci, we aimed to determine levels of cryptic diversity, the invasive or native status of each regional population, and the most appropriate sampling design for identifying the geographic ranges of each evolutionary unit. Results Extensive sampling in Africa, Australasia and South America revealed the existence of "nested" levels of cryptic diversity, in which at least five distinct species can be further subdivided into smaller-scale genetic lineages. The ranges of several evolutionary units are limited by well-documented biogeographic disjunctions. Evidence for both cryptic native diversity and the existence of invasive populations allows us to considerably refine our view of the native versus introduced status of the evolutionary units within Pyura stolonifera in the different coastal communities they dominate. Conclusions This study illustrates the degree of taxonomic complexity that can exist within widespread species for which there is little taxonomic expertise, and it highlights the challenges involved in distinguishing between indigenous and introduced populations. The fact that multiple genetic lineages can be native to a single geographic region indicates that it is imperative to obtain samples from as many different habitat types and biotic zones as possible when attempting to identify the source region of a putative invader. "Nested" cryptic diversity, and the difficulties in correctly identifying invasive species that arise from it, represent a major challenge for managing biodiversity.

The influence of fire regimes on soil microbial diversity in montane grasslands is a relatively unexplored area of interest. Understanding the belowground diversity is a crucial stepping-stone toward unravelling community dynamics, nutrient sequestration, and overall ecosystem stability. In this study, metabarcoding was used to unravel the impact of fire disturbance regimes on bacterial and arbuscular mycorrhizal fungal community structures in South African montane grasslands that have been subjected to an intermediate (up to five years) term experimental fire-return interval gradient. Bacterial communities in this study exhibited a shift in composition in soils subjected to annual and biennial fires compared to the controls, with carbon and nitrogen identified as significant potential chemical drivers of bacterial communities. Shifts in relative abundances of dominant fungal operational taxonomic units were noted, with Glomeromycota as the dominant arbuscular mycorrhiza observed across the fire-return gradient. A reduction in mycorrhizal root colonisation was also observed in frequently burnt autumnal grassland plots in this study. Furthermore, evidence of significant mutualistic interactions between bacteria and fungi that may act as drivers of the observed community structure were detected. Through this pilot study, we can show that fire regime strongly impacts bacterial and fungal communities in southern African montane grasslands, and that changes to their usually resilient structure are mediated by seasonal burn patterns, chemical drivers, and mutualistic interactions between these two groups. [ABSTRACT FROM AUTHOR]