Evaluación de la rectitud del fuste en seis procedencias de Pinus pinaster Ait.

Stem straightness was analyzed in six Spanish provenances of Pinus pinaster Ait.. Three methods were used: subjective punctuation by three different observers, type of curvature and “equivalent curvature” method (based on curvature dimensions). Straightness was evaluated in provenance test at two different sites, with 22 and 35 year-old trees respectively. Stem straightness was considered at three different heights, with the basal section showing the largest and more frequent curvatures. Results with the three methods are very similar in as far as the classification of the six provenances, although they differ in the time required and the information obtained. Large differences in stem straightness have been detected in the studied provenances.En este trabajo se evalúa la rectitud del fuste en seis procedencias españolas de Pinus pinaster Ait. mediante tres métodos: puntuación subjetiva dada por tres observadores distintos, tipo de curvatura presentada y método de la “curva equivalente” (a partir de las dimensiones de las curvaturas). La evaluación se realizó en dos parcelas de ensayo de procedencias, de 22 y 35 años de edad respectivamente, y para ello se consideró la altura del tronco dividida en tres partes. La parte basal del tronco ha resultado ser la que mayores y más frecuentes curvaturas presenta. Los tres métodos presentan alta correlación entre ellos a la hora de clasificar las procedencias, si bien difieren en la rapidez de la medición y en la información que puede obtenerse a partir de ellos. Las procedencias estudiadas muestran grandes diferencias en cuanto al carácter rectitud

Efectos del vibrado del pino piñonero (Pinus pinea L.) en el vigor de los árboles: densidad de copa, crecimiento de guías y parásitos de debilidad

In the Northwest of Spain the mechanized harvesting of pine cones is more and more frequenIn order to quantify the effects of vibration on the vigor of the trees, parcels of stone pine were planted in plateau and countryside. Both the mechanized and manual harvests were analyzed in adult and young trees. The growth of the tree shoots was measured. The presence and abundance of three insect plagues was analyzed in those same trees: Tomicus piniperda, Rhyacionia buoliana and Thaumetopoea pityocampa. The average shoot length of those trees manually harvested was superior to that of those mechanically harvested. The difference was very significant in young trees (40-50 years old) in the countryside and in adult trees (more than 80 years) on the plateau. Rhyacionia buoliana was more abundant in adult trees that young trees, but the relation of its abundance with the harvest method was not seen. The presence of Tomicus piniperda was rare and was only detected in mechanically harvested stands. Thaumetopoea pityocampa was more frequent in trees harvested by hand than those harvested mechanically and was more abundant in young stands. The percentage tree of defoliation was low in all stands independent of harvest method.En el noroeste de España es cada vez más frecuente la recolección mecanizada de piña. Para cuantificar los efectos del vibrado sobre el vigor de los árboles se instalaron en montes de páramo y de campiña parcelas donde se realizó cosecha mecanizada y manual en arbolado adulto y joven. Se midió el crecimiento de los brotes y se analizó la presencia y abundancia de tres insectos plaga sobre estos árboles, Tomicus piniperda y Rhyacionia buoliana, considerados parásitos de debilidad, así como Thaumetopoea pityocampa. La longitud media de los brotes fue superior en árboles cosechados manualmente. La diferencia es importante en árboles jóvenes (40-50 años) de campiñas y en árboles adultos (más de 80 años) de páramos. Rhyacionia buoliana fue más abundante en árboles adultos que en arbolado joven, pero no se vio relación de su abundancia con el método de cosecha. Tomicus piniperda fue escaso y sólo se detectó en rodales cosechados mecanizadamente. Thaumetopoea pityocampa es más frecuente en rodales cosechados manualmente, y en rodales jóvenes lo que indica que selecciona los árboles de crecimiento más vigoroso para alimentarse. Los porcentajes de defoliación fueron bajos en todas las parcelas

Maturation of maritime pine (Pinus pinaster Ait.) seedlings after exposure to a period of continuous light

National audienc

Genetic control of stem form in Pinus pinaster Ait. seedlings exposed to lateral light

In order to compare family differences in stem form determination, seedlings of eight half-sib progenies of Pinus pinaster were exposed to three different light treatments fixed lateral light (T1), alternate lateral light (T2), and direct sunlight (T3). From spatial coordinates of several points along the stem we computed four variables global leaning (GL), apical leaning (APL), flexuosity index (FL) and length of the stem (LEN). Based on comparisons of the four variables, the phototropic stimulus caused different responses in stem form at the familial level. Treatment had an important effect on stem form, although the familial response to treatments was quite variable. Heritability values (h2) of the four analyzed variables showed a different pattern of variation for the three treatments, being very stable for LEN and FL, whereas h2 of APL was much greater based on T1 and T2 compared to T3, and h2 of GL based on T2 was much greater compared to T3 and T1. Differences in stem form were due not only to photomorphogenetic response to different light stimuli, but also to the straightening processes such as compression wood formation. The results suggest that lateral light treatments may he useful in revealing differences in efficiency of the mechanisms involved in stem form determination

Extensive clonal assemblies in Populus alba and Populus x canescens from the Iberian peninsula

Riparian vegetation in temperate zones holds great environmental importance and thus its conservation should be a priority. Among riverine tree species, genus Populus stands out, being also a model organism in research. In this work, we present a genetic analysis of the hybrid Populus x canescens and its parent species Populus alba and Populus tremula, with special emphasis in P. alba with which backcrosses frequently occur. This study focuses on the river Douro basin (Spain) where the presence of hybrids has been previously reported. Nuclear microsatellite markers and Bayesian statistical analysis have been used for the detection of hybrids and purebred stands. This methodology has also made possible the study of clonality in the taxonomic continuum P. alba-P. x canescens. Our results highlight the existence of a small number of genotypes accounting for most of the individual trees and stands. Possible causes leading to this situation are discussed. Also, the presence of individuals genetically close to ornamental cultivars is reported for the first time. Finally, concern about the present situation of P. alba genetic resources is brought up. © 2012 Springer-Verlag Berlin Heidelberg

Transferring Atlantic maritime pine improved material to a region with marked Mediterranean influence in inland NW Spain. A likelihood-based approach on spatially adjusted field data

The inland region of Galicia (NW Spain) marks the boundary between the Atlantic climate of the coastal area and the typical Mediterranean climate of central Spain. Compared to the Atlantic coast, climate in this area has a pronounced summer drought, lower annual precipitation, and higher annual thermal oscillation. Despite the high productivity and ecological importance of maritime pine in inland Galicia, local forest reproductive material (FRM) of high genetic quality is not available for this area. Seed sources originating elsewhere and of unknown adaptation to this area are commonly used for reforestation. With the aim of finding new sources of FRM for this region and exploiting the genetic gains of existing breeding programmes, we analysed the performance in field conditions of improved families of the Coastal Galicia (CG) and Western Australia (WA) breeding programmes. Growth, stem characteristics and branch habit were evaluated in five progeny trials established following a coastal-to-inland gradient. Likelihood-based analyses were used to estimate genetic correlations between environments and to test statistically for causes and patterns of genotype x environment interaction. Because of the strong non-random spatial structures and heterogeneity of residual variances, the analyses were carried out using heterogeneous residual variance mixed models on spatially adjusted data. The results indicated that there is not sufficient evidence to subdivide Galicia into the two current deployment areas. Interaction patterns do not reveal significant differences between zones, and crossover interactions for height growth are present both between and within areas. On the inland sites, the Atlantic improved materials clearly outperformed unimproved seedlots tested in adjacent provenance trials, suggesting the feasibility of using both the CG and WA breeding materials as sources of FRM for reforestation in inland Galicia. Of the two, the WA material showed excellent results for all traits. The inclusion of this material into the Galician maritime pine breeding population should be strongly considered.This study was supported by the Instituto Nacional de Tecnologia Agraria y Alimentaria (INIA) projects RTA05-173 and RTA07-100.Peer reviewe