The Siberian pine growth dynamics in Altai Mountains, China / A dinâmica de crescimento do pinheiro siberiano nas montanhas de Altai, China

Climatic factors play an essential role in the growth of tree ring width. In this study, we aimed to evaluate the correlation between climatic variables and tree-ring growth characteristics of Pinus sibirica in Altai mountains, northwestern China. This study being is first of its kind on climate growth analysis of Pinus sibirica in northwestern China. The study showed great potential to understand the species growing under the specific climatic conditions. Total of 70 tree cores collected from three sites in the sampling area, out of which 63 tree cores considered for this study. The effect of climatic variables which was studied include precipitation, temperature and PDSI. Our results showed that Tree Ring Width chronology has a significantly positive correlation with the late winter (March) temperature and significant negative correlation with the July temperatures. A significant correlation was observed with the late summer precipitation whereas no significant relation found with the Palmer Drought Severity Index. These significant correlations with temperature and precipitation suggested that this tree species had the potential for the reconstruction of the past climate in the area.

Fatores climáticos desempenham papel essencial no crescimento da largura dos anéis das árvores. Neste estudo, objetivou-se avaliar a correlação entre variáveis climáticas e características de crescimento de anéis de árvores de Pinus sibirica nas montanhas de Altai, noroeste da China. Este estudo é o primeiro desse tipo na análise do crescimento climático de Pinus sibirica no noroeste da China. O estudo mostrou grande potencial para entender as espécies que crescem sob as condições climáticas específicas. Total de 70 testemunhos coletados em três locais na área de amostragem, dos quais 63 testemunhos considerados para este estudo. O efeito das variáveis climáticas estudadas incluem precipitação, temperatura e PDSI. Nossos resultados mostraram que a cronologia da Largura do Anel da Árvore tem uma correlação significativamente positiva com a temperatura do final do inverno (março) e uma correlação negativa significativa com as temperaturas de julho. Uma correlação significativa foi observada com a precipitação do final do verão, enquanto nenhuma relação significativa foi encontrada com o Índice de Severidade de Seca de Palmer. Essas correlações significativas com a temperatura e precipitação sugeriram que esta espécie de árvore tinha o potencial para a reconstrução do clima passado na área.

Transferencia de nutrientes y crecimiento de Pinus greggii Engelm. inoculado con hongos comestibles ectomicorrícicos en dos sustratos / Nutrient transfer and growth of Pinus greggii Engelm. inoculated with edible ectomycorrhizal mushrooms in two substrates

La ectomicorriza es una simbiosis mutualista de enorme importancia en la producción de árboles de valor forestal. Uno de los criterios de selección de hongos ectomicorrícicos de gran interés es su comestibilidad, por la importancia económica, ecológica y cultural de los hongos comestibles ectomicorrícicos como un producto forestal no maderable. En este estudio se evaluó el efecto de la inoculación con los hongos comestibles ectomicorrícicos, Laccaria laccata, Laccaria bicolor y Hebeloma leucosarx, en el crecimiento y el contenido nutricional de Pinus greggii, crecido en un sustrato experimental, o en un sustrato comercial enriquecido con un fertilizante de liberación lenta. Dos años después de la siembra, se observaron diferencias en el crecimiento aéreo y radical y en el contenido de macro- y micronutrientes entre plantas inoculadas y no inoculadas, independientemente de la especie fúngica y del sustrato utilizado. Las plantas crecidas en el sustrato comercial tuvieron mayor crecimiento y contenido de nutrientes; sin embargo, sus porcentajes de colonización fueron menores que los de plantas crecidas en el sustrato experimental. Existieron diferencias en la transferencia de nutrientes a la parte aérea de las plantas inoculadas, al comparar entre las especies fúngicas implicadas. Se observó transferencia de Ca por L. laccata, de Na por L. bicolor y de Mn por H.leucosarx en el sustrato experimental. La selección de sustratos constituye un factor clave en la producción de plantas ectomicorrizadas y las tres especies de hongos comestibles ectomicorrícicos evaluados tienen un potencial relevante para la micorrización controlada de P. greggii.

An ectomycorrhiza is a mutualistic symbiosis of paramount importance in forestry and tree production. One of the selection criteria of ectomycorrhizal fungi that has currently gained importance is their edibility due to the economic, ecological and cultural relevance of edible ectomycorrhizal mushrooms as a non-timber forest product. The effect of the inoculation with three edible ectomycorrhizal mushrooms: Laccaria laccata, Laccaria bicolor y Hebeloma leucosarx, which are widely sold in Mexico, on the growth and nutrient contents of Pinus greggii grown in an experimental substrate and a commercial substrate enriched with a slow-release fertilizer, was evaluated. Two years after sowing, differences in terms of shoot and root biomass and macro and micronutrient contents between inoculated and non-inoculated plants, were recorded independently of the fungal species and the substrate. Despite the fact that plants grown in the commercial substrate had higher growth and nutrient contents, their ectomycorrhizal colonization percentages were smaller than those of the plants grown in the experimental substrate. The differences in the nutrient transfer to the inoculated plant shoots among the evaluated fungal species were recorded. Ca mobilization by L. laccata, Na by L. bicolor and Mn by H. leucosarx were observed in the plants growing in the experimental substrate. It has been demonstrated that the selection of substrates constitutes an important factor in the production of ectomycorrhizal plants and that the three evaluated species of edible ectomycorrhizal mushrooms have an enormous potential in the controlled mycorrhization of P. greggii.

What deters plant colonization in a tropical pine plantation? / ¿Cuáles son los factores que limitan la colonización vegetal en una plantación de pino tropical?

AbstractPine plantations in the tropics are often employed to recondition eroded slopes from mudslides, as the Pinus caribaea plantation that shields the Universidad Simón Bolívar campus in Caracas (Venezuela). However, mismanagement of this plantation has led to its rapid degradation. The best option to maintain the protective service is to restore the plantation and direct its successional trajectory towards the neighbouring montane forest. Through experimental manipulation, we aimed to determine which factors block secondary succession and to investigate their effects. Within the experimental constraints imposed by the plantation small area, we analysed the effects of light and fertility limitation, litter accumulation and access to seed on plantation restoration. Light availability was manipulated by clearing and thinning three 800 m2 main plots. Fertilization and litter removal was applied to sub-plots within the light plots. Soils were analysed, microclimate was monitored and, for four years, stem density, species richness and basal area were tallied. Our results showed that light accessibility was the main factor deterring the successional trajectory of the plots, with varying grades of interaction with the sub-treatments. By the end of the fourth year, the cleared plot showed the largest responses in all traits (triplicating stem density and basal area and >20 times higher species richness). The main colonizers were Croton megalodendron, Ocoteafendleri, and Clusia spp. all dominant trees in the nearby native forest. We concluded that the results of this pioneer study, showed that small clearings, repeated in 3-4 year cycles are appropriate for similar restoration schemes. This procedure would create a mosaic of vegetation patches at different successional stages while protecting the slopes from erosion and increasing local biodiversity. Rev. Biol. Trop. 64 (2): 461-471. Epub 2016 June 01.

ResumenEn los trópicos, las plantaciones de pino se emplean comúnmente para proteger laderas erosionadas. Este es el caso de la plantación de Pinus caribaea que resguarda el campus de la Universidad Simón Bolívar en Caracas (Venezuela) de los deslaves de lodo. Sin embargo, el inadecuado manejo de la plantación está conduciendo a su rápido deterioro. La opción más adecuada para mantener el papel protector de la plantación es la restauración dirigida hacia una sucesión similar a la del bosque montano vecino. Mediante manipulaciones experimentales nos proponemos determinar cuáles son los factores que bloquean la sucesión secundaria e investigar sus efectos específicos. Dentro de las limitaciones impuestas por el reducido tamaño de la plantación y su rol protector, aquí analizamos los efectos de la reducida radiación solar y fertilidad del suelo, la acumulación de acículas de pino y el acceso a la fuente de semillas para la restauración. La disponibilidad de radiación solar se varió cortando y entresacando los pinos de parcelas de 800 m2. Los tratamientos de fertilidad y la remoción de acículas (por fuego y manualmente) se realizaron en subparcelas replicadas dentro de las parcelas principales. Los suelos se analizaron fisicoquímicamente, se monitoreo el microclima y, durante 4 años, se censó la densidad, el área basal y la riqueza de especies de los elementos leñosos en las parcelas. Los resultados muestran que el acceso a la radiación solar fue el factor principal que influyó sobre la colonización y crecimiento de nuevos individuos en las parcelas con diversos grados de interacción con los sub-tratamientos. Al finalizar el cuarto año, la parcela totalmente deforestada mostró las respuestas más elevadas (tres veces superior en cuanto a densidad y área basal y hasta veinte veces mayor en cuanto a riqueza de especies) comparada con las parcelas control y parcialmente deforestada. Las principales especies leñosas colonizadoras fueron: Croton megalodendron, Ocotea fendleri y Clusia spp., todas ellas dominantes en el bosque montano vecino. Concluimos que este estudio pionero muestra que el aclareo total de parcelas pequeñas, repetido en ciclos de 3-4 años es apropiado para proyectos de restauración similares. Así se obtendría un mosaico de vegetación en diferentes estadios sucesionales que mantienen el papel protector de la cubierta vegetal e incrementando la biodiversidad local.

Caracterización morfológica de Acremonium sp. asociado a Neonectria fuckeliana en Pinus radiata en Chile / Morphological characterization of Acremonium-like asociated with Neonectria fuckeliana in Pinus radiata in Chile

En este estudio se realizaron los primeros aislamientos del estado asexual del patógeno Neonectria fuckeliana asociado a cancros o ®revirado del pino¼ en plantaciones de Pinus radiata. Se caracterizaron morfológicamente las cepas del sinanamorfo semejante a Verticillium (Acremonium), obtenidas en cultivo in vitro a partir de peritecios. El material para los aislamientos consistió en trozos de corteza de P. radiata con presencia de peritecios, colectados en Toltén, región de La Araucanía, lugar donde se realizó el primer reporte de N. fuckeliana en Chile. Se utilizaron diez cepas del semejante a Acremonium para la caracterización morfológica, mediciones de estructuras fúngicas, ritmo de crecimiento in vitro y morfología de las colonias. Las colonias presentaron un micelio flocoso y ralo de bordes blanquecinos e irregulares, destacándose tres tipos de colonias, blancas, naranjo oscura y naranjo claro. Taxonómicamente, las cepas coinciden con las estructuras mencionadas en la literatura, caracterizándose por la presencia de glioconidios. Las fialides midieron entre 7 – 78,4 x 1,4 - 4,9 ìm. Los conidios, de formas ovoides y algunas bicelulares, midieron entre 4,2 - 8,4 x 2,6 - 3,5 ìm. El ritmo de crecimiento in vitro fue lento, completando su desarrollo a los 19 días con un promedio de 71 +/- 0,3 mm de diámetro, a una tasa de crecimiento diario de 3,8 mm. Los resultados obtenidos hacen necesario futuros estudios de carácter molecular para analizar la variabilidad genética poblacional que puede presentarse en Chile.

First Neonectria fuckeliana isolates in Chile. Strains of Acremonium obtained from in vitro peritecia culture were morphologically characterized. The samples were collected in Toltén, La Araucanía region, were Neonectria fuckeliana was first reported in Chile. The material used for the isolation came from pieces of Pinus radiata bark with peritecia. Ten Acremonium-like strains were used for characterization of fungal structures, in vitro growth and strains morphology. The colonies were a floccose mycelium and thin edges whitish and irregular, varying color highlighting three types of strains, white, dark orange and pale orange. Taxonomically, the strains match the structures referred in the literature, characterized by the presence of gliospores. The phialides dimensions ranged from 7 to 7.8 ìm long and 1.4 to 4.9 ìm wide. The conidio of ovoid shapes and some bicelular measured between 4.2 to 8.4 ìm in length and width 2.6 and 3.5 ìm. In vitro growth rates were slow, the complete development take19 days with a daily growth average of 71 +/-3 mm in diameter, at a rate of 3.8 mm. It is necessary future molecular studies to analyze the population genetic variation that may occur in Chile.

Soil seed bank and the effect of needle litter layer on seedling emergence in a tropical pine plantation

The soil seed bank is the basis for community establishment and permanence and plays a primary role in natural restoration of degraded or altered ecosystems. As part of a restoration project, this study aimed to quantify the soil seed bank and to evaluate the effect of the needle litter layer on seedling emergence. Soil samples from a pine plantation were collected at random in the field and set to germinate in a greenhouse. Half of them were covered by a 6cm layer of dead pine needles simulating field conditions. in the field, 20x20cm plots were established, half were left intact and half were cleaned from the litter needles. All four treatments had 15 replicates and seedling emergence was recorded during six months. Soil seed bank density was 1 222/m² from 17 morphotypes. in the field, the number of morphotypes and seedlings was only 9% and 6% respectively, of those emerged in the greenhouse, possibly due to watering and lack of predation in the latter. in both cases, herbs and graminoids were the dominant emerging seedlings, making up to 70-90% of the total. The needle layer didn’t prevent seeds from reaching the soil but strongly reduced (>50%) seedling emergence, although high variability within treatments resulted in no statistically significant differences. These results show that the needle layer hinders germination and/or emergence of seedlings from the seed bank. its removal may be a recommended technique to accelerate natural restoration in pine plantations. Rev. Biol. Trop. 59 (3): 1071-1079. Epub 2011 September 01.

El banco de semillas del suelo es la base para el establecimiento y la permanencia de una comunidad y desempeña un papel fundamental en la restauración natural de los ecosistemas degradados o alterados. Como parte de un proyecto de restauración, este estudio tuvo como objetivo cuantificar el banco de semillas del suelo y evaluar el efecto de la capa de hojarasca de pino sobre la emergencia de las plántulas. Las muestras de suelo de la plantación de pinos fueron recolectadas al azar en el campo y se pusieron a germinar en un invernadero. La mitad de ellas estaban cubiertas por una capa de 6cm de hojarasca simulando condiciones de campo. En el campo se establecieron parcelas de 20x20cm, la mitad se dejaron intactas y la otra mitad se limpiaron de la hojarasca. Para los cuatro tratamientos se realizaron 15 repeticiones y la emergencia de plántulas se registró durante seis meses. La densidad del banco de semillas del suelo fue de 1 222/m² de 17 morfotipos. En el campo, el número de morfotipos y plántulas fue sólo de 9% y 6% respectivamente, de los que emergieron en el invernadero, posiblemente debido al riego y la falta de depredación. En ambos casos las plántulas dominantes fueron las hierbas y gramíneas, alcanzando el 70-90% del total. La capa de hojarasca no impidió que las semillas llegaran al suelo, pero se presentó una emergencia de plántulas muy reducida (>50%), debido a la alta variabilidad de los tratamientos no se produjeron diferencias estadísticamente significativas. Estos resultados muestran que la capa de hojarasca impide la germinación y/o la emergencia de las plántulas del banco de semillas del suelo. Su eliminación puede ser una técnica recomendada para acelerar la restauración natural en las plantaciones de pino.

Inhibitory effect of jasmonic acid and ethylene on epicotyl growth and bud induction in the maritime pine, Pinus pinaster Soland. in Ait

Two independent parameters, epicotyl height (cm) and number of induced buds were studied on Pinus pinaster explants to analyse the effects of three phytohormones (6-benzylaminopurine, jasmonic acid, ethylene) which were combined or not in 11 different treatments. Epicotyle length diminished significantly in relation to the control medium (medium without exogen phytohormones) in presence of jasmonic acid, 6-benzylaminopurine or Ethephon (which is converted to ethylene in plants) in any of treatments. Concentrations of 100 microM of jasmonic acid and Ethephon had a greater inhibitory effect than the treatments with 10 microM. In addition to that, jasmonic acid was a stronger inhibitor than Ethephon in any of the tried combinations. There were no significant differences between the control treatment and the treatment s with only 10 microM of jasmonic acid or Ethephon. However, 10 microM 6-benzylaminopurine induced bud formation. The different combinations of 6-benzylaminopurine with jasmonic acid and Ethephon showed that concentrations of 10 to 100 microM did not affect the number of induced buds. Jasmonic acid had an inhibitory effect which Ethephon only showed when combined with 100 microM of jasmonic acid and 10 microM of 6-benzylaminopurine. Three response groups were defined by cluster analysis: group 1 produced the greatest mean number of buds (4 to 5) and a mean epicotyl growth of 1 to 1.5 cm; group 2 produced 2 to 4 buds and a mean growth of 0.5 to 1.2 cm; group 3 produced only one bud and a mean epicotyl length of 1.2 to 2 cm.

Sustitución de la sabana nativa con plantaciones de Pinus caribaea (Pinaceae) en Venezuela: efecto sobre parámetros indicadores de cambios en el carbono del suelo

Substitution of native savanna by Pinus caribaea (Pinaceae) plantations in Venezuela: effect on parameters that indicated changes in soil carbon content. A great extension (615 000 ha) of native savannas of the eastern plains of Venezuela have been replaced by plantations of Pinus caribaea var. hondurensis; however, only scarce information exists about the impact of this land use on carbon dynamics in soils. We studied the effect of temporal variability and the substitution on the total organic carbon (TOC), water-soluble carbon (WSC), microbial biomass C (Cmic), basal respiration (BR), microbial metabolic quotient (qCO2) and Cmic/Corg ratio. Selected chemical properties and biological parameters of soils were measured under 3 and 29 year old forest plantations of P. caribaea and an adjacent native savanna which was considered the control. At each site, nine soil composite samples were collected (0-10 cm depth). The studied parameters did not show a defined pattern in relation to temporal variability. Higher carbon preservation occurs in soil microbial biomass under pine plantations. The basal respiration rate and qCO2 suggests that there is a more efficient microbial carbon utilization in the plantations. The Cmic/Corg ratio shows that the microbial biomass has an important stock of soil carbon in pine plantations. The conversion of savannas to pine plantations can increase soil carbon in the eastern plains of Venezuela, but this must be balanced with the ecological importance of natural savannas ecosystems. Rev. Biol. Trop. 56 (4): 2041-2053. Epub 2008 December 12.

Una gran extensión (615000 has) de las sabanas nativas de los Llanos Orientales de Venezuela está siendo reemplazada por plantaciones de Pinus caribaea var. hondurensis; sin embargo, hasta ahora existe escasa información sobre el impacto de este manejo del suelo sobre los parámetros indicadores de la dinámica del carbono en el suelo. El objetivo de esta investigación fue determinar el efecto de la variabilidad temporal y la sustitución sobre el contenido de carbono orgánico total (COT), carbono hidrosoluble (CHS), carbono microbiano (Cmic), respiración basal (RB), cociente metabólico microbiano (qCO2) y la relación Cmic/Corg. Las propiedades químicas y parámetros biológicos seleccionados fueron determinados en plantaciones de P. caribaea de 3 y 29 años de edad y en una sabana nativa adyacente a estas plantaciones, la cual fue considerada como control. En cada sitio de muestreo recolectamos nueve muestras compuestas (0-10 cm de profundidad). Los parámetros estudiados no mostraron un patrón definido in relación a la variabilidad temporal. Hay mayor preservación del carbono dentro de la biomasa microbiana presente en suelos de Uverito en plantaciones de pinos. La tasa de respiración basal y el cociente metabólico indican que en estos suelos existe una comunidad microbiana poco activa, la cual es más eficiente en la utilización del carbono en las plantaciones de pino. La relación Cmic/Corg indica que en las plantaciones la biomasa microbiana constituye una importante reserva del carbono en el suelo. La sabana nativa a plantaciones de pino caribeño en estos suelos puede ser considerada un manejo efectivo para incrementar la calidad del suelo en los llanos orientales de Venezuela, siempre y cuando se tome en cuenta la importancia ecológica de las sabanas.

Modeling individual tree mortality for crimean pine plantations.

Individual tree mortality model was developed for crimean pine (Pinus nigra subsp. pallasiana) plantations in Turkey. Data came from 5 year remeasurements of the permanent sample plots. The data comprises of 115 sample plots with 5029 individual trees. Parameters of the logistic equation were estimated using weighted nonlinear regression analysis. Approximately 80% of the observations were used for model development and 20% for validation. The explicatory variables in the model were ratio of diameter of the subject tree and basal area mean diameter of the sample plot as measure of competition index for individual trees, basal area and site index. All parameter estimates were found highly significant (p < 0.001) in predicting mortality model. Chi-square statistics indicate that the most important variable is d / d(q), the second most important is site index, and the third most important predictor is stand basal area. Examination of graphs of observed vs. predicted mortality rates reveals that the mortality model is well behaved and match the observed mortality rates quite well. Although the phenomenon of mortality is a stochastic, rare and irregular event, the model fit was fairly good. The logistic mortality model passed a validation test on independent data not used in parameter estimation. The key ingredient for obtaining a good mortality model is a data set that is both large and representative of the population under study and the data satisfy both requirements. The mortality model presented in this paper is considered to have an appropriate level of reliability.

A dendroecological study on Pinus nigra Arn. at different altitudes of northern slopes of Kazdaglari, Turkey.

This study was carried out to investigate the relationship between tree ring widths of Pinus nigra in Kazdaglari having humid and very humid climatic conditions. Sixty two trees were cut from 24 sampled points from different altitudes in Kazdaglari to measure treering widths. To determine the responses to the climate, correlation coefficients between treering widths and climatic data were calculated during biological years from October of the previous year to September of the current year In lower altitudes, where climate type is humid, spring and summer precipitation affect the growth of tree rings, but they are not statistically limiting factors. In higher altitudes, this effect is weaker. As a result, we can conclude that the negative effects of the drought are still not clear on the Pinus nigra trees under humid and very humid climatic conditions and at the northern slopes in submediterranean mountainous regions in Turkey.

Seed germination of three provenances of Pinus brutia (Ten.) as influenced by stratification, temperature and water stress.

Seeds from three provenances of Pinus brutia were stratified for 0 or 45 d (days) at 4 +/- 1 degrees C and then germinated at 15 degrees C or 20 degrees C on filter paper saturated with polyethylene glycol solutions to provide water potentials of 0, -0.2 and -0.4 MPa (mega Pascal). Regardless of stratification, germination was lower at 15 degrees C than 20 degrees C for seeds of all provenances. Stratification significantly increased germination percentage at all water potentials regardless of the germination temperatures. Lowering the water potential to -0.4 MPa reduced germination for all three provenances in unstratified and stratified seeds when averaged for two temperatures, but reaction to the increased water stress was different among the provenances. Combined over two temperatures, stratified or unstratified seeds from the highest elevation (Cehennemdere) had the lowest germination performance at all water potentials, and stratified and nonstratified seeds from a coastal elevation (Silifke) had the highest germination parameters at the lowest water potential (-0.4 MPa). It might be concluded that seed germination and resistance to water stress vary according to provenance and stratification.

A diameter increment model for Crimean pine (Pinus nigra Arnold) and Calabrian pine (Pinus brutia Ten.) stands in Isparta region, Turkey.

The purpose of this research was to test the precision of a diameter increment model for the estimation of future periodic diameter increment. Individual trees of Crimean pine (Pinus nigra Arnold) and Calabrian pine (Pinus brutia Ten.) located in both natural and plantation stands were selected. For that reason, normal closed canopy, pure, even-aged and undisturbed stands were examined. In 2002, plots were sampled in three natural and three plantation stands in Isparta region of Turkey. The number of sampling points in sample plots ranged from 19 to 55. In each sampling point, a subject tree and six competitors were selected. In each sampling point, subject tree and competitor trees were stem mapped (x and y coordinate system), and diameter (dbh), total height, age, and 10-yrs radial increment recorded. The predictors of a distance dependent diameter increment model were chosen that included tree level (diameter (d), competition index (CI), and age (t)) and stand level (basal area (G), and site index (SI)) characteristics as well as their transformations. The best fit index of the regression model was pursued in trials with variable combinations. The models explained 65%, 60%, 68% and 50% of the variation in individual tree diameter increment of Crimean pine and Calabrian pine for both natural and plantations stands, respectively. These models can be estimated diameter increment of individual trees at highly significant level (p<0.001).

A Floricaula/Leafy gene homolog is preferentially expressed in developing female cones of the tropical pine Pinus caribaea var. caribaea

In angiosperms, flower formation is controlled by meristem identity genes, one of which, FLORICAULA (FLO)/LEAFY (LFY), plays a central role. It is not known if the formation of reproductive organs of pre-angiosperm species is similarly regulated. Here, we report the cloning of a conifer (Pinus caribaea var. caribaea) FLO/LFY homolog, named PcLFY. This gene has a large C-terminal region of high similarity to angiosperm FLO/LFY orthologs and shorter regions of local similarity. In contrast to angiosperms, conifers have two divergent genes resembling LFY. Gymnosperm FLO/LFY proteins constitute a separate clade, that can be divided into two divergent groups. Phylogenetic analysis of deduced protein sequences has shown that PcLFY belongs to the LFY-like clade. Northern hybridization analysis has revealed that PcLFY is preferentially expressed in developing female cones but not in developing male cones. This expression pattern was confirmed by in situ hybridization and is consistent with the hypothesis of PcLFY being involved in the determination of the female cone identity. Additionally, mutant complementation experiments have shown that the expression of the PcLFY coding region, driven by the Arabidopsis LFY promoter, can confer the wild-type phenotype to lfy-26 transgenic mutants, suggesting that both gymnosperm and angiosperm LFY homologs share the same biological role.