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This study examines the growth patterns, leaf morpho-anatomical traits and physiological characteristics of three ornamental taxa of Alocasia: A. melo, A reginae and Alocasia × morfontanensis 'Bambino'. Using optical and scanning electron microscopy, the research obtained anatomical details of the leaves. Alocasia × morfontanensis 'Bambino' exhibited the highest leaf growth rate among the taxa studied, showing significant leaf number increases from the 8th to the 12th week after planting. Alocasia melo produced 2–3 new basal shoots after 20 weeks, whereas the other two taxa did not produce any. Alocasia melo displayed the greatest relative water content and leaf thickness, while A. reginae showed the highest chlorophyll stability. This study also revealed variations in the adaxial and abaxial leaf color, stomatal width, epidermal thickness, and elemental composition among the taxa involved, with A. melo containing rhodium and high levels of calcium on their leaf surface. These findings contribute to the understanding of the Alocasia leaf morpho-anatomy and growth, which is useful for optimizing Alocasia cultivation and production across diverse ecosystems. [ABSTRACT FROM AUTHOR]

Context. Andropogon gayanus, commonly known as gamba grass, is one of the declared weeds of national significance in Australia. Past studies have focused on gross morphology of root structures, biogeochemical behaviour, and ecology, but there has been limited work on comparative descriptions of leaf micromorphology and anatomy. Aims. We investigated and described its leaf micromorphology and anatomy to understand weed biology and ecophysiology. Methods. Optical and scanning electron microscope examination of the adaxial and abaxial leaf surfaces of A. gayanus was carried out. We identified and generated a list of morphological characters that were used to compare several dried herbarium specimens of A. gayanus. Key results. The leaf characters were consistent across all specimens examined, with minor differences in leaf pubescence, indicating this could be a plastic trait. Conclusions. Andropogon gayanus leaves are well adapted to wet and dry tropical conditions. Plasticity in leaf surface pubescence possibly enhances its adaptability, increasing its success as a weed in Australian ecosystems. The success of A. gayanus in Australia could be because the environment compares favourably with the native environment of the species in Africa, where it has adapted to extremes of wet and dry conditions over a large geographical range. Implications. Plant morphological and taxonomic studies of A. gayanus focused on describing characters of spikelets and caryopses are recommended to understand how reproductive structures aid in its successful proliferation. [ABSTRACT FROM AUTHOR]

The taxonomy of Neurachninane has been unstable, with its member genera consisting of Ancistrachne , Calyptochloa , Cleistochloa , Dimorphochloa , Neurachne , Paraneurachne and Thyridolepis , changing since its original circumscription that comprised only the latter three genera. Recent studies on the phylogeny of Neurachninae have focused primarily on molecular data. We analysed the phylogeny of Neurachninae on the basis of molecular data from seven molecular loci (plastid markers: mat K, ndh F, rbc L, rpl 16, rpo C2 and trn LF, and ribosomal internal transcribed spacer, ITS) and morphological data from 104 morphological characters, including new taxonomically informative micromorphology of upper paleas. We devised an impact assessment scoring (IAS) protocol to aid selection of a tree for inferring the phylogeny of Neurachninae. Combining morphological and molecular data resulted in a well resolved phylogeny with the highest IAS value. Our findings support reinstatement of subtribe Neurachninae in its original sense, Neurachne muelleri and Dimorphochloa rigida. We show that Ancistrachne , Cleistochloa and Dimorphochloa are not monophyletic and Ancistrachne maidenii , Calyptochloa , Cleistochloa and Dimorphochloa form a new group, the cleistogamy group, united by having unique morphology associated with reproductive dimorphism. This study of native Australian grasses shows the impact on results from analyses of multiple datasets. The study builds on previous work using an expanded set of DNA sequences and a more comprehensive study of the morphology of seed heads to show new species, new genera and a new classification for a group of grasses defined by sharing a rare and distinct breeding system. [ABSTRACT FROM AUTHOR]