Factors affecting variation in outcrossing rate in Eucalyptus globulus

2004 ◽  
Vol 52 (6) ◽  
pp. 773 ◽  
Author(s):  
Briony Patterson ◽  
René E. Vaillancourt ◽  
David J. Pilbeam ◽  
Brad M. Potts
Keyword(s):  
Eucalyptus Globulus ◽  
Seed Orchard ◽  
Forest Tree ◽  
Self Incompatibility ◽  
Factors Affecting ◽  
Seed Collection ◽  
Clonal Seed Orchard ◽  
Canopy Position ◽  
Outcrossing Rates ◽  
Individual Trees

The mating system of the animal-pollinated forest tree species Eucalyptus globulus Labill. was investigated in a clonal seed orchard to determine the importance of self-incompatibility, floral timing, floral abundance and canopy position on explaining variation in outcrossing rates. Outcrossing rates were highly and significantly correlated with the degree of self-incompatibility of individual genotypes (R2 = 0.92). Outcrossing rates were also significantly higher in the upper than in the lower parts of tree canopies (0.78 ± 0.1 and 0.54 ± 0.1, respectively). In contrast, neither flowering time nor abundance of flowers on individual trees revealed consistent effects upon outcrossing rates, suggesting that these factors are either less important or inherently more unpredictable because their effects partly depend on complex interactions with animal pollinators. Screening seed orchards in order to identify trees with high self-incompatibility and restricting seed collection to these trees will ensure that a high proportion of the seed used for plantations is derived from outcrossing, thereby minimising the deleterious effects of inbreeding depression.

scholarly journals Seed Germination Variation among Crop Years from a Pinus sylvestris Clonal Seed Orchard

2019 ◽  
pp. 1-14
Author(s):  
Melusi Rampart
Keyword(s):  
Seed Germination ◽  
Seed Weight ◽  
Seed Orchard ◽  
Climatic Conditions ◽  
Thermal Time ◽  
Base Temperature ◽  
Germination Capacity ◽  
Seed Collection ◽  
Clonal Seed Orchard ◽  
The Mean

Maternal effects were assessed by germinating seeds sourced over multiple years from the same cloned mother trees, comparing germination capacity and rate between crop years. The relationships between climatic variables, seed characteristics and germination capacity were determined, and thermal time parameters were used to predict seed dormancy release and germination under the climatic conditions in the year after seed collection. There were significant differences in seed weight (P < 0.05), seed length and embryo occupancy (both P < 0.001) among crop years. Temperature during the seed development period explained 70% of the variation in seed weight and 63% of the variation in embryo occupancy. Germination capacity was significantly (P <0.001) different among crop years, among temperatures and among chilling durations, and thermal time requirements for germination increased from older (2007) to younger (2012) seeds. The mean base temperature without chilling was 7.1°C, while after chilling it was 4.6°C and 3.6°C for four and eight weeks chilling respectively. The mean thermal time to 50% germination without chilling was 135.1°Cd, while after chilling it was 118.3°Cd and 154.0°Cd for four and eight weeks chilling respectively. This experiment demonstrates that year-to-year differences in the environment experienced by mother trees during seed maturation can affect seed germination characteristics.

scholarly journals Sources of variation in self-incompatibility in the Australian forest tree, Eucalyptus globulus

2010 ◽  
Vol 105 (5) ◽  
pp. 737-745 ◽  
Author(s):  
Marian H. McGowen ◽  
René E. Vaillancourt ◽  
David J. Pilbeam ◽  
Brad M. Potts
Keyword(s):  
Eucalyptus Globulus ◽  
Forest Tree ◽  
Self Incompatibility ◽  
Sources Of Variation

scholarly journals The use of self-incompatibility in the production of hybrid eucalyptus seed by `Aracruz Celulose' in Brazil

1998 ◽  
Vol 21 (3) ◽  
pp. 375-379 ◽  
Author(s):  
Tatiana Góes Junghans ◽  
Ingrid Peters-Robinson ◽  
Fernando L. Bertolucci ◽  
Acelino Couto Alfenas
Keyword(s):  
Interspecific Hybridization ◽  
Genetic Parameters ◽  
Eucalyptus Grandis ◽  
Seed Orchard ◽  
Outcrossing Rate ◽  
Self Incompatibility ◽  
Use Of Self ◽  
Hybrid Eucalyptus ◽  
Individual Trees ◽  
High Degree

Self-incompatibility found in a Eucalyptus grandis clone was used to promote interspecific hybridization between E. grandis and E. urophylla clones. The interspecific hybridization achieved in an open-pollinated commercial seed orchard planted in Espírito Santo, Brazil was evaluated by the multi-locus outcrossing rate (tm) of the seed producing clone, E. grandis. The percentage of outcrossed seeds reached 95.9%. The outcrossing rate of individual trees was quite variable, but was always above 70.0%. Wright's coefficient was negative (F = -0.30) revealing an excess of heterozygous genotypes in the progeny. Genetic parameters confirmed the high degree of hybridization expected in this orchard. The 800-m wide protection belt of native tropical forest that surrounds this orchard has significantly reduced pollen contamination, in comparison to a 400-m wide belt used in another local seed orchard.

scholarly journals Intracone variation explains most of the variance in Picea abies seed weight: implications for seed sorting

2016 ◽  
Vol 46 (4) ◽  
pp. 470-477 ◽  
Author(s):  
Katri Himanen ◽  
Pekka Helenius ◽  
Tiina Ylioja ◽  
Markku Nygren
Keyword(s):  
Picea Abies ◽  
Seed Weight ◽  
Variance Component ◽  
Seed Orchard ◽  
Poor Quality ◽  
Forest Stand ◽  
Variance Component Analysis ◽  
Clonal Seed Orchard ◽  
Variation Explained ◽  
Individual Trees

Norway spruce (Picea abies (L.) Karst.) seed is collected from both forest stands after final felling and from seed orchards. To produce high-germinability seed lots that are easy to use in nursery sowing machines, empty, insect-damaged, and other poor-quality seeds are culled. Sorting is done typically by weight or size. Previous studies of conifer seed have indicated wide variation in seed weight between individual trees or clones. However, the intratree or intraclone variations have rarely been taken into account, and intracone variation in seed weight has not been examined. We collected cones from a forest stand and from a clonal seed orchard in central Finland. Each seed from each cone was extracted, weighed, and x-rayed to assess their quality. Trees and clones differed in terms of the proportions of different quality seed. Variance component analysis showed that the intracone variation explained a larger proportion of the total variation in seed weight than did the intercone/intertree or interclone variations. Thus weight-based seed sorting has less effect on the genetic diversity of a seed lot than previously believed. We also conclude that the large differences in proportion of full seed among trees and clones impact the contribution of genotypes in seed and, eventually, in seedling lots.

Update on the Boundaries of the Curly Birch Range

2020 ◽  
pp. 9-21
Author(s):  
L.V. Vetchinnikova ◽  
◽  
A.F. Titov ◽  
◽  
Keyword(s):  
Population Size ◽  
Natural Populations ◽  
Forest Tree ◽  
Published Data ◽  
Population Approach ◽  
Key Factors ◽  
History Of ◽  
Individual Trees ◽  
Karelian Birch

The article reports on the application of the best known principles for mapping natural populations of curly (Karelian) birch Betula pendula Roth var. carelica (Mercklin) Hämet-Ahti – one of the most appealing representatives of the forest tree flora. Relying on the synthesis and analysis of the published data amassed over nearly 100 years and the data from own full-scale studies done in the past few decades almost throughout the area where curly birch has grown naturally, it is concluded that its range outlined in the middle of the 20th century and since then hardly revised is outdated. The key factors and reasons necessitating its revision are specified. Herewith it is suggested that the range is delineated using the population approach, and the key element will be the critical population size below which the population is no longer viable in the long term. This approach implies that the boundaries of the taxon range depend on the boundaries of local populations (rather than the locations of individual trees or small clumps of trees), the size of which should not be lower than the critical value, which is supposed to be around 100–500 trees for curly birch. A schematic map of the curly birch range delineated using this approach is provided. We specially address the problem of determining the minimum population size to secure genetic diversity maintenance. The advantages of the population approach to delineating the distribution range of curly birch with regard to its biological features are highlighted. The authors argue that it enables a more accurate delineation of the range; shows the natural evolutionary history of the taxon (although it is not yet officially recognized as a species) and its range; can be relatively easily updated (e.g. depending on the scope of reintroduction); should be taken into account when working on the strategy of conservation and other actions designed to maintain and regenerate this unique representative of the forest tree flora.

scholarly journals Estimation of Genetic and Phenotypic Parameters for Growth Traits in a Clonal Seed Orchard of Pinus kesiya in Malawi

ISRN Forestry ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Edward Missanjo ◽  
Gift Kamanga-Thole ◽  
Vidah Manda
Keyword(s):  
Growth Traits ◽  
Seed Orchard ◽  
Direct Selection ◽  
Tree Model ◽  
Individual Tree ◽  
Individual Level ◽  
Clonal Seed Orchard ◽  
Pinus Kesiya ◽  
Individual Tree Model ◽  
The Individual

Genetic and phenotypic parameters for height, diameter at breast height (dbh), and volume were estimated for Pinus kesiya Royle ex Gordon clonal seed orchard in Malawi using an ASReml program, fitting an individual tree model. The data were from 88 clones assessed at 18, 23, 30, 35, and 40 years of age. Heritability estimates for height, dbh, and volume were moderate to high ranging from 0.19 to 0.54, from 0.14 to 0.53, and from 0.20 to 0.59, respectively, suggesting a strong genetic control of the traits at the individual level, among families, and within families. The genetic and phenotypic correlations between the growth traits were significantly high and ranged from 0.69 to 0.97 and from 0.60 to 0.95, respectively. This suggests the possibility of indirect selection in trait with direct selection in another trait. The predicted genetic gains showed that the optimal rotational age of the Pinus kesiya clonal seed orchard is 30 years; therefore, it is recommended to establish a new Pinus kesiya clonal seed orchard. However, selective harvest of clones with high breeding values in the old seed orchard should be considered so that the best parents in the old orchard can continue to contribute until the new orchard is well established.

Paternity analysis with microsatellites in a Danish Abies nordmanniana clonal seed orchard reveals dysfunctions

2006 ◽  
Vol 36 (4) ◽  
pp. 1054-1058 ◽  
Author(s):  
O K Hansen ◽  
E D Kjær
Keyword(s):  
Asymptotic Variance ◽  
Seed Orchard ◽  
Paternity Analysis ◽  
Effective Population ◽  
Population Number ◽  
Clonal Seed Orchard ◽  
Relative Contribution ◽  
Male Gametes ◽  
Abies Nordmanniana ◽  
The Status

A paternity analysis using five microsatellite markers was conducted in a Danish clonal seed orchard with 13 Abies nordmanniana (Stev.) Spach clones. The purpose was to investigate potential seed-orchard dysfunctions, with special emphasis on nonequal pollen contributions and selfing. Male paternity was found for 232 seedlings germinated from seeds collected on three ramets, each of eight clones, and the relative contribution of each clone to the gene pool of male gametes was calculated. Furthermore, 49 ramets were genotyped to check for erroneous grafting. The effect of an unbalanced male contribution was quantified by means of two measures: (1) the status number (NS), which reflects buildup of coancestry in the seed-orchard crop as a result of a low number of clones and an unequal male contribution, and (2) the asymptotic variance effective population number (Ne(v)). The contributions by pollen donors from the 13 clones were highly skewed. Three clones were fathers to more than 75% of the progenies, while making up only 24% of the ramets in the seed orchard. Four clones sired no progenies at all. The unequal contribution on the male side corresponded to NS = 4.2 and Ne(v) = 5.8. Some selfing was observed, which may give rise to concern if clonal seed orchards with few clones are established. The estimated maximum pollen contamination from outside the seed orchard was 4.3%. No grafting–labelling errors were identified.

Intraspecific variation in drought susceptibility in Eucalyptus globulus is linked to differences in leaf vulnerability

2019 ◽  
Vol 46 (3) ◽  
pp. 286 ◽  
Author(s):  
Christopher J. Lucani ◽  
Timothy J. Brodribb ◽  
Greg Jordan ◽  
Patrick J. Mitchell
Keyword(s):  
Drought Tolerance ◽  
Intraspecific Variation ◽  
Eucalyptus Globulus ◽  
Forest Tree ◽  
Species Variation ◽  
Important Species ◽  
Phenotypic Differences ◽  
Hydraulic Failure ◽  
Xylem Vulnerability ◽  
Alternative Approach

Understanding intraspecific variation in the vulnerability of the xylem to hydraulic failure during drought is critical in predicting the response of forest tree species to climate change. However, few studies have assessed intraspecific variation in this trait, and a likely limitation is the large number of measurements required to generate the standard ‘vulnerability curve’ used to assess hydraulic failure. Here we explore an alternative approach that requires fewer measurements, and assess within species variation in leaf xylem vulnerability in Eucalyptus globulus Labill., an ecologically and economically important species with known genetic variation in drought tolerance. Using this approach we demonstrate significant phenotypic differences and evidence of plasticity among two provenances with contrasting drought tolerance.

scholarly journals IDENTIFICATION OF TEAK MISTLETOE SPECIES AND BASIC INFORMATION OF UTILIZATION AS MEDICINAL PLANT

2016 ◽  
Vol 7 (3) ◽  
pp. S61-S63
Author(s):  
Zainal Muttaqin ◽  
Sri Wilarso Budi R ◽  
Basuki Wasis ◽  
Iskandar Z Siregar ◽  
Corryanti .
Keyword(s):  
Medicinal Plant ◽  
Seed Orchard ◽  
Forest Product ◽  
Hemiparasitic Plants ◽  
Clonal Seed Orchard ◽  
Host Trees ◽  
Key Species ◽  
Chemical Content ◽  
High Control ◽  
Attack Intensity

Mistletoe is hemiparasitic plants (macroparasite) on seasonal and annual plants include trees, however, mistletoes are also beneficial as key species that fill in the ecological niche, and a potential to non-wood forest product such as medicinal plants as one of them. The objectives of this research are to identify species of teak mistletoes at Padangan Clonal Seed Orchard (CSO) in Perum Perhutani and to aim its posibilities as medicinal plant. The inventory methods on species of teak mistletoes was carried out in compartements/blocks of teak clones that are designated as Observation Sample Plots (OSPs/PCP) of the attack intensity from low, medium, high, control; and four units Observation Measurement Plots (OMPs/PUP) on each OSPs/PCP. Continously, it was analized by comparing the same species of mistletoes on other host trees as reference which was efficacious to be used as medicinal plant. Three species of mistletoes parasitizing teak clone stands were identified as Dendrophthoe pentandra (L.) Miq. of family of Loranthaceae which is also attacking other host trees, Macrosolen tetragonus (Blume) Miq. of family of Loranthaceae too, Viscum articulatum Burm. F. of family of Santalacea/Viscaceae that is hyperparasite on two other mistletoes. The comparison with the same teak mistletoe but on different host trees shows that including D. pentandra and V. articulatum have the potential for hypertension treatment. D. pentandra is used too for medicine to cure ilness, wounds, fester and recovery from parturition. Known that chemical content this mistletoe comprise of flavonoid ingrident, fenolat acid (terulat acid, para hidroksi benzoate acid, kumarat acid, protokatekuat acid and vanilat acid. As for the utilization of M. tetragonus hasn’t been discovered up to this moment.Key words: mistletoe, identification, teak clone, non-wood forest product, medicinal plant

scholarly journals Aboveground Biomass Stockpile of Trees in Vallanadu Blackbuck Sanctuary, Peninsular India

2021 ◽  
Vol 16 (3) ◽  
pp. 755-763
Author(s):  
M. Nagaraj M. Nagaraj ◽  
M. Udayakumar
Keyword(s):  
Aboveground Biomass ◽  
Tamil Nadu ◽  
Basal Area ◽  
Single Species ◽  
Forest Tree ◽  
Annual Rainfall ◽  
Dry Forests ◽  
Peninsular India ◽  
Tree Inventory ◽  
Individual Trees

A forest tree inventory study was conducted in Vallanadu Black buck sanctuary, Tuticorin. The current study was conducted to assess tree density, species richness, basal area (BA) and aboveground biomass (AGB) stockpile. The study area has been classified as Southern Thorn Forest (SFT). One hundred square plots (total area 1 ha), each 10m × 10m (100 m2 each) laid randomly across study area. All live trees with ≥5 cm diameter at breast height (DBH) measured at 137 cm above the ground. As the whole, 1335 individual trees ≥5cm DBH recorded. A total number of 18 species recorded from 14 genera and 11 families in study area. The family Mimosaceae has maximum number of species (7 species) followed by Rhamnaceae (2 species), while 9 families had just single species’ each. The total basal area recorded was 22.046 m2 ha-1, while, the mean wood density (WD) of trees estimated as 0.70±0.093 g cm-3. Total amount of 50.065 Mg ha-1 present in STF. The contribution of different species in terms of total AGB varied significantly. Commiphora berryi stocked 45.13% (22.588 Mg ha-1) of AGB followed by A. planifrons (23.31%, 11.669 Mg ha-1), A. mellifera (7.233%, 3.621 Mg ha-1), whereas remaining 15 species collectively stocked 24.327% (12.187 Mg ha-1) AGB. The STF had a large number of trees compared to some dry forests within Tamil Nadu. Southern Thorn Forest endowed with a moderate number of trees species. Aboveground biomass stockpile of trees is comparable with the range recorded from Indian dry forests. The study area experiences lesser mean annual rainfall and >6 months dry season. Further, endowed with short-bole and smaller leaved trees, hence stocked a relatively lesser AGB in trees.

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