Societal Impact Statement: Plants and agricultural practices are an integral part of human food systems and well‐being. Here, an example of an ethnobotanical research approach is provided to increase our understanding of the relationship between plants and human activities in Madagascar, where the agricultural sector is the local economy basis. This research examines weeds of the Poaceae family, assessing their recognition and societal impacts, and quantifying farmers' perception of the Poaceae weed's status in cropping systems. A better understanding of farmers' weed knowledge will strengthen our ability to inclusively support rural highland Malagasy food systems, incorporating science with traditional knowledge.Summary: Research on the perceptions and knowledge of Poaceae weeds was conducted in three areas of Madagascar's central highlands: Itremo massif, Ambohidray village and Vakinankaratra region. This work aims to identify the best‐known species and understand their roles in crop and livestock systems. Additionally, it presents detailed data on Digitaria species. The approach was based on field surveys and farmer's interviews, with plant voucher specimens and photographs to facilitate identification. Relative frequency of citations, confidence interval, and use values indexes were calculated to assess cultural significance. We carried out 111 interviews, where 87 taxa were mentioned, of which 51 are Poaceae, including 11 Digitaria species. Farmers classify the Poaceae weeds in three ways: their impacts on agricultural activities, use category and vegetative growth patterns, the latter especially significant for Digitaria. Locally common grasses are perceived as weeds when they are abundant and cause yield loss. The most damaging species is Digitaria humbertii, confirmed by half of the interviews. More than 40% of the farmers use Poaceae weeds in composting, more than 20% as fodder, and more than 8% as medicine. Overall, 67% of the species mentioned are judged useful. The diversity of useful species and the associated indigenous knowledge is important to the local communities, but, weeds are still perceived as negative generally. The Poaceae are overall neglected in Malagasy ethnobotany, and an in‐depth analysis of farmer knowledge is needed. The data obtained will be useful for future studies and the conservation of agrobiodiversity, especially endemic species that are not widely known.

Background and Aims: Millet crops in the grass genus Digitaria include white and black fonio (D. exilis and D. iburua), raishan (D. compacta) and Polish millet (D. sanguinalis), cultivated across West Africa, India and Europe. Fonio and raishan crops are important in supporting food security and subsistence agricultural systems in rural communities, while D. sanguinalis is no longer cultivated. These crops are resilient to challenging climates. We aim to produce an integrated study of these crops: a phylogeny of the Digitaria genus including all four food species, to identify key crop wild relatives; time-calibrated biogeographic analysis, to investigate the history and evolution of Digitaria; and a morphological study to assess the transition between wild and domesticated species. Methods: We use the Angiosperms353 target-enrichment sequencing approach to produce maximum likelihood and coalescent model nuclear phylogenies for 46 Digitaria species, and Bayesian methods to propose an evolutionary and biogeographic history for the genus. Morphology of wild and cultivated species is investigated for spikelets and growth habits using microscopy and SEM imaging. Key Results: Four distinct evolutionary lineages are found for the Digitaria crops, and we identify new close crop wild relatives D. fuscescens, D. atrofusca, D. setigera, D. radicosa, and D. ciliaris. South and eastern Africa is proposed as a likely origin of early Digitaria divergence, with crop lineages diverging from wild relatives around 2–6 mya. Incomplete domestication traits are observed, including the loss of trichomes, but no clear change in appearance for spikelet or abscission zone morphologies. Conclusions: The knowledge produced in this study about Digitaria crop wild relatives will be useful in improving crop traits through targeted breeding and physiological studies, and we also highlight the need for conservation of seed material through programmes working with local partners for these important climate-tolerant indigenous cereals.

Background and aims – Acridocarpus belongs to one of the seven Malpighiaceae lineages that dispersed from the Neotropics to the Paleotropical region, being by far the most widely diversified and distributed genus of the family in Africa. In this study, we tested the monophyly and validity of the current infrageneric classification of Acridocarpus with a dated molecular phylogeny. We also reconstructed ancestral range distributions for biomes and continents to elucidate which route led to the colonisation of Africa by the most recent common ancestor (MRCA) of this genus. Material and methods – We sampled six genes (ITS, PHYC, matK , ndhF , rbcL , and trnL-F ), 21 species of Acridocarpus , and three outgroup species to test the monophyly of the infrageneric classification of the genus. BI and ML analyses were performed for the combined molecular dataset. A total of 20 morphological characters were optimised on the tree. Calibration points derived from a published Malpighiaceae chronogram were used for a dating analysis. Ancestral areas of Acridocarpus and its relatives were estimated for continental (South America, Africa, India, Madagascar, and New Caledonia) and biome (dry forests, humid forests, and savannas) ranges. Key results – The pre-existing infrageneric classification of Acridocarpus was recovered as non-monophyletic due to being solely based on homoplastic morphological characters. The MRCA of Acridocarpus colonised rainforests of East Africa + Madagascar 43 Mya via the Gondwana route and greatly diversified in this region, with a single long-distance dispersal event from Madagascar to New Caledonia (Oceania). The genus colonised African dry forests at least four different times, starting in the Oligocene and diversified a single time in Malagasy savannas in the Miocene.