Recent diversification followed by secondary contact and hybridization may explain complex patterns of intra- and interspecific morphological and genetic variation in the North American hard pines (Pinus section Trifoliae), a group of approximately 49 tree species distributed in North and Central America and the Caribbean islands. We concatenated five plastid DNA markers for an average of 3.9 individuals per putative species and assessed the suitability of the five regions as DNA bar codes for species identification, species delimitation, and phylogenetic reconstruction. The ycf1 gene accounted for the greatest proportion of the alignment (46.9%), the greatest proportion of variable sites (74.9%), and the most unique sequences (75 haplotypes). Phylogenetic analysis recovered clades corresponding to subsections Australes, Contortae, and Ponderosae. Sequences for 23 of the 49 species were monophyletic and sequences for another 9 species were paraphyletic. Morphologically similar species within subsections usually grouped together, but there were exceptions consistent with incomplete lineage sorting or introgression. Bayesian relaxed molecular clock analyses indicated that all three subsections diversified relatively recently during the Miocene. The general mixed Yule-coalescent method gave a mixed model estimate of only 22 or 23 evolutionary entities for the plastid sequences, which corresponds to less than half the 49 species recognized based on morphological species assignments. Including more unique haplotypes per species may result in higher estimates, but low mutation rates, recent diversification, and large effective population sizes may limit the effectiveness of this method to detect evolutionary entities.

Pinus subsection Ponderosae includes approximately 17 tree species distributed from western Canada to Nicaragua. We inferred phylogenetic relationships of multiple accessions for all widely recognized species from 3.7 kb of cpDNA sequence (matK, trnD-trnY-trnE spacer, chlN-ycf1 spacer, and ycf1). The sister relationship between subsections Ponderosae and Australes was corroborated with high branch support, and several clades, most with lower branch support, were identified within subsection Ponderosae. Pinus jeffreyi was sister to P. coulteri, P. sabiniana, and P. torreyana. Californian accessions of P. ponderosa and P. washoensis occurred in a clade separate from P. arizonica and P. scopulorum from the southwestern United States. Western Mexican species P. cooperi and P. durangensis had cpDNA sequences identical to one or more accessions of P. arizonica and P. scopulorum, and together these taxa were closely related to clades of P. engelmannii-P. devoniana (Mexico) and P. douglasiana-P. yecorensis-P. maximinoi (western Mexico to Guatemala). A well supported clade of taxa from Mexico and Central America included P. pseudostrobus, P. montezumae, P. hartwegii, P. maximinoi (one of three accessions), P. nubicola, and P. donnell-smithii. Chloroplast DNA sequences were nonmonophyletic for most species, although the degree of support varied.

Trichoderma species are fungi widely employed as plant-growth-promoting agents and for biological control. Several commercial and laboratory-made solid formulations for mass production of Trichoderma have been reported. In this study, we evaluated a solid kaolin-based formulation to promote the absortion/retention of Trichoderma asperellum in the substrate for growing tomato plants. The unique implementation of this solid formulation resulted in an increased growth of the tomato plants, both in roots and shoots after 40 days of its application. Plants were challenged with two fungal pathogens, Fusarium oxysporum and Botrytis cinerea, and pretreatment with T. asperellum resulted in less severe wilting and stunting symptoms than non-treated plants. Treatment with T. asperellum formulation inhibited Reactive Oxygen Species (ROS) production in response to the pathogens in comparison to plants that were only challenged with both pathogens. These results suggest that decrease in ROS levels contribute to the protective effects exerted by T. asperellum in tomato.

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A sensory evaluation was performed for coffee samples using the Check-All-That-Apply (CATA) method. The samples included Mexican coffee from Hidalgo and Colima states. The brews were prepared by the espresso and French press methods. The data obtained were analyzed using Cochran´s Q test in order to determine any significant differences between samples. There were significant differences (P < .05) only in visual attributes, due to intrinsic characteristics of the preparation methods of the samples. Additionally, the results were analyzed using Multiple Correspondence Analysis (MCA), where from a two-dimensional graphic, differences and similarities between samples and attributes were observed. In the same way, it was observed that visual attributes had greater influence for the description of the samples.

The acceleration of climate change is necessitating the adoption of shifts in farming practices and technology to ensure the sustainability of agricultural production and food security. Because abiotic stresses such as drought and chilling represent major constraints on agricultural productivity worldwide, in this study, the mitigation of such stresses by the fungus Trichoderma asperellum HK703 was evaluated. The fungus was grown on whole grain oats, kaolin and vermiculite for 5 days and then the formulation was mixed with the potting soil to colonize the roots of the plants. The effect of the bioinoculant on tomato under drought or chilling was analyzed in tomato (Solanum lycopersicum) plants. Leaf, stem and root succulence, electrolyte leakage, the relative growth rate of plant height, stem thickness and leaf area, as well new leaf emergence and chlorophyll content were determined. The results showed that drought or chilling increased electrolyte leakage and reduced plant growth and development traits and chlorophyll (a,b) content. However, inoculation with T. asperellum eliminated or reduced most of the negative impacts of drought compared to the non-stressed plants, with the exception of chlorophyll b content. Furthermore, inoculation with T. asperellum improved some of the evaluated features in chilling stressed plants but had no effect on plant height or chlorophyll (a,b) content. The results of this study indicate that T. asperellum was more effective in alleviating drought than chilling stress in tomato plants.

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Antecedentes: Abies hidalgensis es una especie endémica del estado de Hidalgo, México, adscrita en la Lista Roja de la IUCN en la categoría VuD2, que se ha confundido con A. guatemalensis en algunas poblaciones donde hay extracción de madera en rollo reportada como A. religiosa, lo que genera duda sobre las o la especie que se distribuyen y aprovechan en el estado de Hidalgo. Preguntas y / o Hipótesis: ¿Qué especie o especies del género Abies se distribuyen y aprovechan en Hidalgo, México?,¿Cuál es la distribución geográfica de A. hidalgensis? Especies de estudio: Abies hidalgensis, A. religiosa. Sitio y años de estudio: Municipios de Acaxochitlán, Acoculco, Agua Blanca de Iturbide, Epazoyucan, Mineral del Monte, Pachuca, Singuilucan, Tenango de Doria, Tepeapulco y Zimapán, en el estado de Hidalgo. Años 2015 a 2017. Métodos: Se analizaron 18 caracteres morfológicos mediante análisis de funciones discriminantes. Se estimó la diferenciación genética a partir del análisis de tres microsatélites nucleares desarrollados para A. guatemalensis. Resultados: Abies hidalgensis se distribuye al sureste y Abies religiosa en la zona centro-sur de Hidalgo. Los caracteres morfológicos distintivos son: canales resiníferos, forma del ápice, y caracteres morfológicos asociados a los conos ovulados y las semillas. Los estudios genéticos indican que Abies sp. muestra mayor divergencia y diversidad genética con respecto a A. hidalgensis y A. religiosa. El coeficiente de endogamia es mayor en A. religiosa. Conclusiones: En el estado Hidalgo se distribuyen dos especies del género Abies.