Effect of seedling size on post-planting growth and survival of five Mexican species and their hybrids.

Background: Seedling growth and survival depend on seedling quality. However, there is no experimental evidence showing that the seedling dimensions of the abundant, economically important and widely distributed tree species , , , , and and their hybrids effectively improve survival and growth in reforestations and plantations in Mexico. Therefore, the aim was to evaluate the influence of initial morphological parameters of 2,007 nursery seedlings of these species and their hybrids on their growth and survival 44 months after planting in the Sierra Madre Occidental, Mexico.

Evolutionary drivers of reproductive fitness in two endangered forest trees.

Population genetics theory predicts a relationship between fitness, genetic diversity (H) and effective population size (N), which is often tested through heterozygosity-fitness correlations (HFCs). We tested whether population and individual fertility and heterozygosity are correlated in two endangered Mexican spruces (Picea martinezii and Picea mexicana) by combining genomic, demographic and reproductive data (seed development and germination traits). For both species, there was a positive correlation between population size and seed development traits, but not germination rate.

Natural durability of timber species exposed to xylophagous fungi in southern Durango, Mexico.

Introduction: Wood is a natural resource used for construction and the manufacture of many products. This material is exposed to damage due to biotic and abiotic factors. An important biotic factor is wood-degrading fungi that generate large economic losses.

Assisted migration and the rare endemic plant species: the case of two endangered Mexican spruces.

Background: In the projected climate change scenarios, assisted migration might play an important role in the conservation of the threatened plant species, by translocate them to similar suitable habitats outside their native distributions. However, it is unclear if such habitats will be available for the Rare Endemic Plant Species (REPS), because of their very restricted habitats. The aims of this study were to perform a population size assessment for the REPS Patterson and Martínez, and to evaluate the potential species distributions and their possibilities for assisted migration inside México and worldwide.

Graft survival of Carr. in relation to two grafting techniques with dormant and sprouting buds.

Developing methods for successfully grafting forest species will be helpful for establishing asexual seed orchards and increasing the success of forest genetic improvement programs in Mexico. In this study we investigated the effects of two grafting techniques (side veneer and top cleft) and two phenological stages of the scion buds (end of latency and beginning of sprouting), in combination with other seven grafting variables, on the sprouting and survival of 120 intraspecific grafts of Carr. The scions used for grafting were taken from a 5.

Assessment and Models of Insect Damage to Cones and Seeds of in the Sierra Madre Occidental, Mexico.

Insect damage to cones and seeds has a strong impact on the regeneration of conifer forest ecosystems, with broader implications for ecological and economic services. Lack of control of insect populations can lead to important economic and environmental losses. is the most widespread of the white pines in Mexico and is widely distributed throughout the mountains of northern Mexico.

Morphological Differences in Across Latitudinal and Elevational Gradients.

The phenotype of trees is determined by the relationships and interactions among genetic and environmental influences. Understanding the patterns and processes that are responsible for phenotypic variation is facilitated by studying the relationships between phenotype and the environment among many individuals across broad ecological and climatic gradients. We used , which has a wide latitudinal distribution, as a model species to: (a) estimate the relative importance of different environmental factors in predicting these morphological traits and (b) characterize the spatial patterns of standing phenotypic variation of cone and seed traits across the species' range.

Survival of side grafts with scions from pure species Carr. and the Engelm. var. hybrid.

Grafting is one of the most widely used methods for vegetative propagation, particularly for multiplying trees considered important, but there has been little research done on the effect of hybridization on grafts from the genus . Sometimes hybrids show the ability to reproduce and adapt efficiently to the environment. However, they reduce the genetic gain of seed orchards.

Discrimination of Martinez populations on the basis of climatic, edaphic, dendrometric, genetic and population traits.

Background: , which is endemic to Mexico, is currently listed as "Endangered" on the Red List. Chihuahua spruce is only found in the Sierra Madre Occidental (SMO), Mexico. About 42,600 individuals are distributed in forty populations.

Degree of Hybridization in Seed Stands of Pinus engelmannii Carr. In the Sierra Madre Occidental, Durango, Mexico.

Hybridization is an important evolutionary force, because interspecific gene transfer can introduce more new genetic material than is directly generated by mutations. Pinus engelmannii Carr. is one of the nine most common pine species in the pine-oak forest ecoregion in the state of Durango, Mexico.