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Sage phylogenies have not resolved many shallow level clades within problematic Salvia subgenus Calosphace, hindered by the difficulty in finding sufficiently variable loci. We assembled fifteen chloroplast genomes and nuclear ribosomal cistrons from non-target reads of a nuclear hybrid enrichment project to assess the phylogenetic utility for a closely related group of mainly Mexican sections. Chloroplast synteny is confirmed with 10 Lamiales chloroplasts, supporting a map to reference assembly. Salvia miltiorrhiza Bunge chloroplast was used as a reference for assemblies, averaging 25,970 reads with mean depth of 20.71 reads; genomes ranged from 141,451 to 150,339 bp. The S. carduacea Benth. nuclear ribosomal cistron (18S, ITS1, 5.8S, ITS2 and 26S) was used as a reference for assembly, averaging 66,387 reads and mean depth of 1508 reads. We evaluated several partitioning schemes for plastid, plastid and nrDNA and reduced sampling, to assess whether these would render the same phylogenetic inferences. Maximum likelihood inferences resulted with high bootstrap support and two main clades with interspersed species from Salvia sect. Scorodoniae: clade A with species from S. sects. Atratae and Mitratae and clade B from S. sects. Sigmoideae and Uricae. Only S. sect. Uricae is monophyletic in every analysis supporting its identity, not merged into S. sect. Scorodoniae; S. sect. Sigmoideae is inferred monophyletic only if the ribosomal DNA sequences are included. Greater resolution and higher branch support are obtained with the entire plastome and nrDNA, rather than subsampling highly variable regions; thus we recommend this approach with expanded taxon sampling, coupled with a morphological review to better solve sectional circumscription in closely related S. subgenus Calosphace species.

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Big-leaf mahogany (Swietenia macrophylla) is valued for its high-quality wood and use in urban landscapes in Mexico. During surveys of mango-producing areas in the central western region of Mexico, symptoms of malformation, the most important disease of mango in the area, were observed on big-leaf mahogany trees. The objectives of this research were to describe this new disease and determine its cause. Symptoms on big-leaf mahogany at four sites in Michoacán, Mexico resembled those of the vegetative phase of mango malformation, including compact, bunched growth of apical and lateral buds, with greatly shortened internodes and small leaves that curved back toward the supporting stem. Of 163 isolates that were recovered from symptomatic tissues, most were identified as Fusarium pseudocircinatum (n = 121) and F. mexicanum (n = 39) using molecular systematic data; two isolates represented unnamed phylospecies within the F. incarnatum-equiseti species complex (FIESC 20-d and FIESC 37-a) and another was in the F. solani species complex (FSSC 25-m). However, only F. mexicanum and F. pseudocircinatum induced malformation symptoms on 14-day-old seedlings of big-leaf mahogany. The results indicate that F. mexicanum and F. pseudocircinatum, previously reported in Mexico as causal agents of mango malformation disease, also affect big-leaf mahogany. This is the first report of this new disease and the first time that F. mexicanum was shown to affect a host other than mango.

Mango malformation disease (MMD) caused by Fusarium spp. is an important limiting factor in most production areas worldwide. Fusarium mexicanum and F. pseudocircinatum have been reported as causing MMD in Mexico. These two pathogens also cause a similar disease in Swietenia macrophylla (big-leaf mahogany malformation disease or BLMMD) in central western Mexico, while F. pseudocircinatum was recently reported as causing malformation disease in Tabebuia rosea (rosy trumpet) in the same region. These studies suggest that additional plant species, including weeds, might be hosts of these pathogens. The role that weed hosts might have in the disease cycle is unknown. The objectives of this work were to recover Fusarium isolates from understory vegetation in mango orchards with MMD, identify the Fusarium isolates using DNA sequence data, and determine if F. mexicanum is capable of inducing disease in the weedy legume Senna uniflora (oneleaf senna). Additional objectives in this work were to compare Fusarium isolates recovered from weeds and mango trees in the same orchards, by characterizing their phylogenetic relationships, assessing in vitro production of mycotoxins, and identifying their mating type idiomorph. A total of 59 Fusarium isolates from five species complexes were recovered from apical and lateral buds from four weed species. Two of the species within the F. fujikuroi species complex are known to cause MMD in Mexico. Trichothecene production was detected in five isolates, including F. sulawense and F. irregulare in the F. incarnatum-equiseti species complex and F. boothii in the F. sambucinum species complex. Both mating types were present among mango and weed isolates. This is the first report of herbaceous hosts harboring Fusarium species that cause mango malformation in Mexico. The information provided should prove valuable for further study of the epidemiological role of weeds in MMD, and help manage the disease.

RESUMENL os bosques de pino-encino de la comunidad de Nuevo San Juan, Michoacán, están dominados por Pinus pseudostrobus, P. devoniana y P. leiophylla. Los patrones de variación genética de estas especies no se conocen lo suficiente, particularmente los de P. leiophylla, lo cual limita la creación de lineamientos para el movimiento de semillas y plántulas para reforestación y su adaptación al cambio climático. Las especies se recolectaron en cuatro o cinco procedencias a lo largo de un transecto altitudinal (1,650 a 2,500 m) para el establecimiento de un ensayo en vivero, con el objetivo de cuantificar la variación genética entre y dentro de las especies. La altura de la planta (tres y cinco meses de edad) fue significativamente diferente (P < 0.0001) entre especies. Entre procedencias hubo diferencias significativas para P. devoniana (P < 0.0001) y P. leiophylla (P = 0.0352). La especie P. devoniana mostró un pronunciado patrón de crecimiento asociado con la altitud de origen, donde las plantas con mayor crecimiento procedían de una menor altitud. Las poblaciones de P. leiophylla fueron diferentes sólo a los tres meses de edad, sin un patrón altitudinal estadísticamente significativo. No se encontraron diferencias significativas entre poblaciones de P. pseudostrobus. ABSTRACTP ine-oak forests of San Juan Nuevo, Michoacán are dominated by Pinus pseudostrobus, P. devoniana and P. leiophylla. The patterns of genetic variation of these species are poorly known, particularly those of P. leiophylla, limiting the creation of guidelines for the movement of seeds and seedlings for reforestation and climate change adaptation. Species were collected in four or five provenances along an altitudinal transect (1,650 to 2,500 m) for the establishment of a nursery trial, with the aim of quantifying the genetic variation among and within species. Plant height (three and five months) was significantly different (P < 0.0001) among species. Significant differences among provenances for P. devoniana (P < 0.0001) and P. leiophylla (P = 0.0352) were observed. The species P. devoniana showed a pronounced growth pattern associated with altitude of origin, where the fastest growing plants came from a lower elevation. The populations of P. leiophylla were different only at three months of age, with no statistically significant altitudinal pattern. No significant differences were found among populations of P. pseudostrobus.

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