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Subtribe Eleusininae (Chloridoideae, Poaceae) comprise 237 species with little morphological diversity in inflorescence structure. This diversity may be explained by an evolution from complex (pyramidal, highly branched) to simpler (digitate, barely branched) morphologies. However, only mature specimens have been studied; the developmental analyses of the inflorescences are rare. We analysed the inflorescence, spikelet and flower development of 17 species of Eleusininae using scanning electron microscopy. In the early stages of the transition to flowering of the studied species, the inflorescence meristem elongates initiating primary branches acropetally. The differentiation of these branches along the main axis is either basipetal or amphipetal. Although the initiation of secondary branches along primary branches may be acropetal or amphipetal, their differentiation follows an amphipetal direction. The florets in spikelets are initiated acropetally. We found abnormal orientation of stamens and gynoecium in florets of Leptochloa chloridiformis. The analysis of the ontogeny has enriched current knowledge of inflorescences in the subtribe. In addition, the developmental patterns revealed the existence of more than one developmental pattern leading to similar mature inflorescence forms. The results will support future efforts on postulating trends of developmental patterns across Poaceae. [ABSTRACT FROM AUTHOR]

Background: Megathyrsus maximus is a forage grass native to Africa but widely cultivated in tropical and subtropical regions of the world where it is part of the grazing food chain. This study aimed to evaluate five M. maximus genotypes for the effect of maturity on their morpho-agronomic traits, nutritional composition and digestibility, and to correlate their leaf blade and stem anatomy with their nutritional value., Results: The proportion of sclerenchyma tissues increased as maturity was reached, while lignin accumulation was differentiated between genotypes. Gatton Panic, Green Panic and Mutale genotypes maintained their acid detergent lignin (ADL) values for leaf blades in the three cuts evaluated. In sacco ruminal dry matter disappearance was lower in Green Panic genotype at the vegetative stage for stems, but not for leaf blades. Significant positive correlations were found between dry matter disappearance and mesophyll tissues, and the latter were negatively correlated with neutral detergent fiber (NDF) and ADL., Conclusion: Our results strongly indicate that cutting age and genotype affected the nutritional value of M. maximus leaf blades and stems, with a more pronounced loss of quality in stems than in leaf blades. We recommend increasing the frequency of grazing at early stage or anticipating the stage of stem elongation in Green Panic to produce forage with better nutritional value. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)