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-Shoot elongation, flowering phenology, branch thickening, needle and cone growth was monitored during four years in grafted stone pines in Inner Spain. The relevance of environmental influence on growth and flower regulation in Mediterranean stone pine as nut crop is stressed. Different models of thermal time compute were compared for characterizing phenostage onset, shoot and cone growth response to temperature. Non-linear regression models for relative length of preformed shoots and relative cone diameter were fitted in thermal-time scale. Shoot-growth timing was characterized by a common degree-day sum between years. Correlation of June rainfall with shoot length and flower bearing in the next year and with current needle and branch diameter growth was highly significant. Also, summer shoots and a second female flowering occurred occasionally in leader branches in dependence on June rainfall, but cone-setting failed due to the absence of pollen. Phenological model of the variation between years were consistent with observations in mature non-grafted stone pines. stone pine (Pinus pinea) / growth and flowering phenology / phenology modelling / growing-degree-days Résumé -Modélisation de la croissance des pousses et de la phénologie du Pin pignon greffé (Pinus pinea L.) en Espagne Centrale. L'allongement des pousses, la phénologie de la floraison, l'épaississement des branches et le développement des aiguilles et des cônes ont été suivis pendant quatre ans chez des pins pignon greffés dans une plantation située en Espagne centrale. L'influence des conditions environnementales sur la croissance et la régulation de la floraison est étudiée sur le Pin pignon méditerranéen en tant que producteur de graines. Différents modèles basés sur les sommes des températures (degrés jours) ont été comparés afin de caractériser les stades phénologiques et l'influence de la température sur la croissance des pousses et des cônes. Des modèles de régression non-linéaire ont pu être estimés reliant la longueur relative de la pousse préformée et le diamètre relatif des cônes avec l'échelle de temps thermique. La courbe de croissance des pousses est caractérisée par une même somme de degrés-jour chaque année. Une corrélation significative est établie la pluviométrie du mois de juin et la croissance des aiguilles et la croissance entre épaisseur des branches de l'année courante ou avec la longueur des pousses et la floraison portée l'année suivante. La mise en place d'une pousse estivale et d'une seconde floraison femelle peuvent se produire occasionnellement sur les branches maîtresses en relation avec les précipitations du mois de juin, cependant les cônes ne subissent aucune maturation en raison de l'absence de pollen. Des modèles phénologiques de la variation entre années concorde avec des observations réalisées sur des Pins pignons matures non greffés.pin pignon (Pinus pinea L.) / phénologie de la croissance et de la floraison / modélisation de la phénologie / sommes des températures

In spite of the use of the edible kernels of Stone pine (Pinus pinea L.) gathered from Mediterranean pine forests, the species remains a genuine forest tree that has never been domesticated as an orchard crop. In the last decades, some efforts have been made to select valuable genotypes for exploring the possibilities of Stone pine as an orchard crop. The present paper characterizes the cone yield of a grafted clone bank in order to elucidate the relevance of genetic and environment factors for seed-yield quantity and quality and for sequential transition rates of the development from pollinated conelets to ripe cones. Individual tree size and cone yield were separated in their genetic and environmental components, in order to estimate phenotypic, genetic and environmental correlations. A statistical model for logtransformed individual cone yield was adjusted, ranking the tested genotypes by their estimated clonal value after adjustment for tree size covariables. The degree of genetic determination for adjusted cone yield was estimated in 15%, the expected genetic gain by selection of the top 10% of tested genotypes would be 12%. Genetic correlation between genetic values for cone yield and cone and seed size were weak but significantly positive (r = 0.27 and 0.17), hence the lack of trade-offs between crop quantity and quality will allow a combined selection.

Aim of the study: To present a new spatiotemporal model for Pinus pinea L. annual cone production with validity for Spanish Northen Plateau and Central Range regions. The new model aims to deal with detected deficiencies in previous models: temporal shortage, overestimation of cone production on recent years, incompatibility with data from National Forest Inventory, difficulty for upscaling and ignorance of the inhibitory process due to resource depletion.Area of study: Spanish Northern Plateau and Central Range regions, covering an area where stone pine occupies more than 90,000 ha.Material and methods: Fitting data set include 190 plots and more than 1000 trees were cone production has been annually collected from 1996 to 2014. Models were fitted independently for each region, by means of zero-inflated log normal techniques. Validation of the models was carried out over the annual series of cone production at forest scale.Results: The spatial and temporal factors influencing cone production are similar in both regions, thus the main regional differences in cone yield are related with differences in the phenological timing, the intensity of the influent factors and forest intrinsic conditions. A significant inhibition of floral induction by resource depletion was detected and included into the model. Upscaling the model results in accurate prediction at forest scale.Research highlights:[1] The new model for annual cone production surpass the detected deficiencies of previous models, accurately predicting recent decay in cone production; [2] Regional differences in cone production are due to phenological and seasonal climatic differences rather than to between provenances genetic differences.