Many species from across the vascular plant tree‐of‐life have modified standard plant tissues into tubers, bulbs, corms, and other underground storage organs (USOs), unique innovations which allow these plants to retreat underground. Our ability to understand the developmental and evolutionary forces that shape these morphologies is limited by a lack of studies on certain USOs and plant clades. We take a comparative transcriptomics approach to characterizing the molecular mechanisms of tuberous root formation in Bomarea multiflora (Alstroemeriaceae) and compare these mechanisms to those identified in other USOs across diverse plant lineages; B. multiflora fills a key gap in our understanding of USO molecular development as the first monocot with tuberous roots to be the focus of this kind of research. We sequenced transcriptomes from the growing tip of four tissue types (aerial shoot, rhizome, fibrous root, and root tuber) of three individuals of B. multiflora. We identified differentially expressed isoforms between tuberous and non‐tuberous roots and tested the expression of a priori candidate genes implicated in underground storage in other taxa. We identify 271 genes that are differentially expressed in root tubers versus non‐tuberous roots, including genes implicated in cell wall modification, defense response, and starch biosynthesis. We also identify a phosphatidylethanolamine‐binding protein, which has been implicated in tuberization signalling in other taxa and, through gene‐tree analysis, place this copy in a phylogenetic context. These findings suggest that some similar molecular processes underlie the formation of USOs across flowering plants despite the long evolutionary distances among taxa and non‐homologous morphologies (e.g., bulbs vs. tubers). (Plant development, tuberous roots, comparative transcriptomics, geophytes).

RESUMEN El género neotropical Furcraea Vent. es ampliamente cultivado para la production de fibras conocidas como Fique o Cabuya. Se realizó un análisis histológico de las hojas de tres especies cultivadas en Colombia, con la finalidad de realizar la description comparativa entre ellas. Diferentes secciones de hojas listas para su cosecha fueron procesadas utilizando técnicas histológicas convencionales. Las tres especies presentaron características anatómicas comparativamente muy homogéneas dentro de las que resaltan: epidermis monoestratificada, cutícula gruesa, estomas encriptados, mesófilo no diferenciado, presencia de cristales de oxalato de calcio, fibras esclerenquimáticas de tipo septado asociadas a los haces vasculares o formando cordones y braquiesclereidas asociadas al margen foliar. Estas últimas varían ligeramente entre las especies estudiadas en el lumen, la forma de las punteaduras y el grado de lignificación, lo cual parece estar correlacionado con la dureza del margen foliar. Aparte de las braquiesclereidas, no se advierten suficientes caracteres histológicos que permitan la diferenciación clara entre los cultivares estudiados. Se discute también la anatomía de estas plantas en función de su metabolismo fotosintético.

49• Many species from across the vascular plant tree-of-life have modified standard plant 50 tissues into tubers, bulbs, corms, and other underground storage organs (USOs). Bomarea 51 multiflora (Alstroemeriaceae) is a tropical climbing monocot with unique underground 52 morphology, including tuberous roots. We take a comparative transcriptomics approach 53to characterizing the molecular mechanisms of tuberous root formation in B. multiflora 54 and compare these mechanisms to those identified in other underground storage 55structures across diverse plant lineages. 56• We sequenced transcriptomes from the growing tip of four tissue types (aerial shoot, 57 rhizome, fibrous root, and root tuber) of three individuals of B. multiflora. We identify 58differentially expressed isoforms and test the expression of candidate genes that have 59been implicated in underground storage in other taxa. 60• We identify 271 genes that are differentially expressed in root tubers versus fibrous roots, 61including genes implicated in cell wall modification, environmental signaling and 62flowering time, and starch biosynthesis. We also identify a phosphatidylethanolamine-63binding protein (PEBP) that is over-expressed in tuberous roots. 64• These findings demonstrate that deeply parallel processes underlie the formation of 65 underground storage structures despite long evolutionary distances between taxa and non-66homologous morphologies, illustrating that repeated co-option of similar genetic 67 pathways can lead to convergent morphologies. 68 69Introduction 70 71The vast majority of scientific attention in botanical fields focuses exclusively on aboveground 72biomass. However, a holistic understanding of plant morphology, ecology, and evolution 73requires that considerable research effort go towards generating a comprehensive understanding 74 of belowground biomass. While most studies of plant form and function focus on aboveground 75 organs, on average 50% of an individual plant's biomass lies beneath the ground (Niklas, 2005). 76Often, belowground biomass is thought to consist solely of standard root tissue, but in some 77 cases, plants modify 'ordinary' structures for specialized underground functions. Plants called 78"geophytes" are toward the extreme end of this belowground/aboveground allocation spectrum. 79These species rely on nutrients stored in belowground organs (underground storage organs or 80 "USOs"), and their ephemeral aboveground parts resprout from buds located on belowground 81 organs (Raunkiaer, 1934; Dafni et al., 1981a,b; Al-Tardeh et al., 2008; Veselý et al., 2011). 82Geophytes are ecologically and economically important, morphologically diverse, and have 83 evolved independently in all major groups of vascular plants except gymnosperms (Howard et 84 al., 2019a,b). These plants and their associated underground structures are a compelling example 85 of evolutionary convergence; diverse taxa form a variety of structures, often from different 86 tissues, that serve parallel physiological and ecological functions. ...

Background: Coronavirus infectious disease 2019 (COVID-19) caused by the infection with the new coronavirus SARS-CoV-2 has affected the life and health of more than 222 million people. In the absence of any specific pharmacological treatment, the need to find new therapeutic alternatives is clear. Medicinal plants are widely used worldwide to treat different conditions, including COVID-19; however, in most cases, there are no specific studies to evaluate the efficacy of these treatments. Objective: This article evaluates the antiviral effect of six plant extracts used by indigenous and afro Colombian people against SARS-CoV-2 in vitro. Methods: The antiviral effect of six extracts prepared from plants used in Colombian traditional medicine was evaluated against SARS-CoV-2 through a pre-post treatment strategy on the Vero E6 cell line. Once cytotoxicity was established through an MTT assay, the antiviral effect of the extracts was calculated based on the reduction in the viral titer determined by plaque assay. Results: Gliricidia sepium inhibited SARS-CoV-2 in a 75.6%, 56.8%, 62.5% and 40.0% at 10 mg/mL, 8 mg/mL, 6 mg/mL, and 2 mg/mL, respectively, while P. tuberculatum treatment reduced viral titer in 33.3% at 6 mg/mL after 48h. Conclusion: G. sepium and P. tuberculatum extracts exhibit antiviral activity against SARS-CoV-2 in vitro.

Complex geological events such as mountain uplift affect how, when, and where species originate and go extinct, but measuring those effects is a longstanding challenge. The Andes arose through a series of complex geological processes over the past c. 100 million years, impacting the evolution of regional biota by creating barriers to gene flow, opening up new habitats, and changing local climate patterns. Bomarea are tropical geophytes with ranges extending from central Mexico to central Chile. Of the roughly 120 species of Bomarea, most are found in the Andes, and previous work has suggested that Bomarea diversified rapidly and recently, corresponding with the uplift of the Andes. While many Bomarea species occur over small, isolated ranges, Bomarea edulis occurs significantly beyond the ranges of any other Bomarea species (from central Mexico to northern Argentina) and is thought to have potentially humanmediated dispersal, due to its status as a pre-Columbian food plant. To untangle the potential drivers of diversification and biogeographic history in Bomarea, we used a target-capture approach to sequence nuclear loci of 174 accessions of 124 species, including 16 outgroup species from across the family (Alstroemeriaceae). We included 43 individuals of B. edulis from across its range to assess species monophyly and identify infraspecific phylogeographic patterns. We model biogeographic range evolution in Bomarea and test if Andean orogeny has impacted its diversification. We find that Bomarea originated in the central Andes during the mid-Miocene, then spread north, following the trajectory of major mountain uplift events. Most observed speciation events occurred during the Pleistocene, while global climate cooled and oscillated and the northern Andes achieved their current form. Furthermore, we find that Andean lineages diversified faster than their non-Andean relatives. These results demonstrate a clear macroevolutionary signal of Andean orogeny on this neotropical radiation.