Fertility variation, seed collection and gene diversity in natural stands of Taurus cedar (Cedrus libani)

There are many environmental and biological factors on forestry practices as known. Aspect called as slope faces is one of the most important environmental factors in these practices because of its easy application for managers. Fertility variation defined as an individual ability to give progeny and gene diversity estimated based on effective number of parents were investigated as the proportion of numbers of cones counted from individuals in natural stands sampled aspectual of Taurus cedar (Cedrus libani A. Rich.) for three consecutive years. The averages of cone number were 19.4, 47.2, and 75.5 for the years. It was the highest in flat (23.5) for 2013, in south (92.1) for 2014, and in flat (95.7) for 2015, while it was lowest in south (16.3), in east (18.2), and in north (39.4) for the years, respectively. Significant correlations (p≤0.01) were estimated among years for cone production in polled aspect. Estimated fertility variations changed for the years and stands. It could be generally acceptable level for typical natural stands except of west of 2014. Fertility variations were 1.55, 3.05, and 1.64 in polled stands for the years. Gene diversity was 0.99 for the years in polled stands. North aspect could be taken into consideration in establishment and selection of seed sources and gene conservation areas based on fertility variation and gene diversity.

Download Full-text

Fertility variation among individuals in natural stands of Acacia leucophloea

Silvae Genetica ◽

10.1515/sg-2016-0003 ◽

2016 ◽

Vol 65 (1) ◽

pp. 20-30

Author(s):

V.N. Mutharaian ◽

R. Kamalakannan ◽

V. Narmatha Bai ◽

A. Mayavel ◽

D.-Y. Kim ◽

...

Keyword(s):

Fruit Set ◽

Arid Zone ◽

Gene Diversity ◽

Tree Height ◽

Fruit Production ◽

Skewed Distribution ◽

Effective Population ◽

Ideal Situation ◽

Fertility Variation ◽

Natural Stands

AbstractGrowth characteristics and fertility variations were evaluated at four natural stands of tropical arid zone species,A. leucophloeain southern India. Three stands (TNL 1, TNL 2 and PDM) were situated in dry upland regions while one stand (RKP) was at waterlogged site. The tree height and girth at breast height did not vary between stands in two years. Fertility variation (sibling coefficient, ψ) was estimated based on flowering abundance and fruit set collected for two consecutive years. Fruit production per tree was generally lower in the RKP stand than the other three stands. No year-to-year variation was observed on fruit set in all stands. Growth and flower production showed a weak-positive correlation in both years (R2= 0.39 to 0.1). The correlation to check if the larger inflorescence size, the higher number of fruit production was also failed. Male fertility variation did not vary much among stands (ψm= 1.28 ~ 1.62). Female fertility variation was low (ψf= 1.71 ~ 2.02) in the three stands situated in dry upland regions than the RKP stand (ψf= 4.09 ~ 4.16). The cumulative contribution of trees to the overall fertility was deviated from the ideal situation (equal contribution) in all stands, especially the RKP stand showed a skewed distribution (R2≤ 6.5). The effective population size was low in the RKP predicting a high genetic drift when compared with other sites. Similarly high group coancestry and low gene diversity were observed in the stand RKP. The implications of fertility variation on gene diversity of the species and future management of the natural stands were also discussed.

Download Full-text

Fertility Variation, Genetic Relatedness, and Their Impacts on Gene Diversity of Seeds From a Seed Orchard of Pinus thunbergii

Silvae Genetica ◽

10.1515/sg-2004-0037 ◽

2004 ◽

Vol 53 (1-6) ◽

pp. 202-206 ◽

Cited By ~ 7

Author(s):

K. S. Kang ◽

D. Lindgren ◽

T. J. Mullin

Keyword(s):

Genetic Relatedness ◽

Gene Diversity ◽

Seed Orchard ◽

Pinus Thunbergii ◽

Clonal Seed Orchard ◽

Fertility Variation ◽

The Status ◽

Status Number ◽

Census Number ◽

Natural Stands

AbstractClonal differences in the number of male and female strobili were determined for five consecutive years in a clonal seed orchard of Pinus thunbergii in Korea. The effects of relatedness and clonal differences in reproductive development on gene diversity of seed (in terms of accumulated relatedness by status number) were estimated. While clonal differences were found, fertility variation was not large through all studied years. The orchard clones were divided into different regions and locations based on the geographical distribution and distance of natural stands that plus trees were selected from. Assuming that there was no relatedness among regions, locations and clones, the status number (Ns) was varied from 47.6 to 55.5 for five successive years. On average (pooling), Nswas 92% of census number (N). Assumed relatedness among regions, locations and/or clones decreased the status number. Effect of parental selection on relatedness and orchard management was also discussed.

Download Full-text

Fertility variation, seed collection and gene diversity in natural stands of Taurus cedar (Cedrus libani)

10.21203/rs.3.rs-25470/v1 ◽

2020 ◽

Author(s):

Nebi Bilir ◽

Kyu-Suk Kang

Keyword(s):

Seed Production ◽

Male Fertility ◽

Gene Diversity ◽

Primary Objective ◽

Effective Number ◽

Fertility Variation ◽

Genetic Resources Management ◽

Natural Stands ◽

Seed Stand ◽

Male Strobili

Abstract Background Seed stand is one of the important seed sources that is essential for global seed production programs. The primary objective of seed stands is to produce seeds as fast as possible. Characteristics of seed stand seeds depend mainly on stand quality, fertility variation and mating system. Individual fertility is an ability to produce progeny to next generation. Prediction of fertility variation is useful for seed production, genetic resources management and gene conservation. In this study, we report how to estimate fertility variation and gene diversity, and discuss its effect on the management of natural stands of Taurus cedar. Results Fertility variation and gene diversity were estimated based on the differences of strobilus production in female and male parents from three seed stands of Taurus cedar. A total of 50 trees were randomly chosen from each seed stand, and the female and male strobili were counted for three consecutive years. The coefficients of variation for female and male strobilus production were subjected to estimation female and male fertility variation. The total fertility variation (Ψ) was then estimated from the female and male fertility variation. The effective number of parents (Np) was calculated based on the Ψ. The mean of female strobili ranged from 31 to 150, and that of male strobili ranged between 77 and 828. The Ψ in a good crop year was smaller than in a poor year and the Np varied from 34.7 to 44.2. The Ψ was improved and the Np was increased when strobilus productions were pooled across three years or populations. The equal cone harvest could mitigate the fertility variation among individuals but caused loss of seed production. Conclusions The effective number of parents could estimate gene diversity of seeds from natural stands, which was based on the function of correlated fertility variation between female and male parents. Mixing seeds from different years could improve the fertility variation among individuals and increase the gene diversity of seeds. However, a balancing between the effective number of parents and the number of mixed years or populations should be carefully considered for maintaining the gene diversity.

Download Full-text

Fertility and Effective Population Size in Seedling Seed Orchards of Casuarina equisetifolia and C. junghuhniana

Silvae Genetica ◽

10.1515/sg-2004-0030 ◽

2004 ◽

Vol 53 (1-6) ◽

pp. 164-168 ◽

Cited By ~ 1

Author(s):

M. Varghese ◽

D. Lindgren ◽

A. Nicodemus

Keyword(s):

Gene Diversity ◽

Sex Expression ◽

Low Fertility ◽

Equal Proportion ◽

Casuarina Equisetifolia ◽

Effective Population ◽

Coastal Site ◽

Seed Orchards ◽

Seed Collection ◽

Fertility Variation

Abstract Two seedling seed orchards each of C. equisetifolia and C. junghuhniana established by thinning provenance trials in coastal and inland locations in South India were evaluated for sex expression and fertility variation at four years. More than 80% of the trees in C. equisetifolia orchards were fertile in both sites with a similar pattern of more (almost 2 times) female trees and equal proportion of monoecious and non-flowering trees. In C. junghuhniana, the coastal orchard had twice the proportion of fertile trees as that of the inland. Orchards established in coastal environment had less fertility variation and hence maintained lower coancestry values in both species. Coastal site has more trees contributing effectively to seed production than inland locations and the orchards maintain higher (almost two times) effective population sizes. Genetic drift is also 3 times higher in inland locations in both species. Male and female trees in inland orchards of both species however had greater reproductive output than coastal trees. Monoecious Casuarina equisetifolia trees showed a different trend of greater male fertility in coastal site, but seed output was the same in both locations. Gene diversity values of all orchards are high though it is marginally higher in coastal sites. Measures like constrained seed collection from large number of trees and promoting representation of superior provenances with low fertility would be useful in checking diversity loss during domestication.

Download Full-text

Gender, reproductive output covariation and their role on gene diversity of Pinus koraiensis seed orchard crops

BMC Plant Biology ◽

10.1186/s12870-020-02632-9 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Ji-Min Park ◽

Hye-In Kang ◽

Da-Bin Yeom ◽

Kyu-Suk Kang ◽

Yousry A. El-Kassaby ◽

...

Keyword(s):

Gene Diversity ◽

Fundamental Equation ◽

Seed Orchard ◽

Pinus Koraiensis ◽

Effective Number ◽

Effective Population ◽

Management Options ◽

Fertility Variation ◽

Census Number ◽

Seed Crops

Abstract Background Gender and fertility variation have an impact on mating dynamics in a population because they affect the gene exchange among parental members and the genetic composition of the resultant seed crops. Fertility is the proportional gametic contribution of parents to their progeny. An effective number of parents, derivative of effective population size, is the probability that two alleles randomly chosen from the gamete gene pool originated from the same parent. The effective number of parents is directly related to the fertility variation among parents, which should be monitored for manipulating gene diversity of seed crops. We formulated a fundamental equation of estimating the effective number of parents and applied it to a seed production population. Results Effective number of parents (Np) was derived from fertility variation (Ψ) considering covariance (correlation coefficient, r) between maternal and paternal fertility. The Ψ was calculated from the coefficient of variation in reproductive outputs and divided into female (ψf) and male (ψm) fertility variation in the population under study. The Np was estimated from the parental Ψ estimated by the fertility variation of maternal (ψf) and paternal (ψm) parents. The gene diversity of seed crops was monitored by Ψ and Np. in a 1.5 generation Pinus koraiensis seed orchard as a case of monoecious species. A large variation of female and male strobili production was observed among the studied 52 parents over four consecutive years, showing statistically significant differences across all studied years. Parental balance curve showed greater distortion in paternal than maternal parents. The Ψ ranged from 1.879 to 4.035 with greater ψm than ψf, and the Np varied from 14.8 to 36.8. When pooled, the relative effective number of parents was improved as 80.0% of the census number. Conclusions We recommend the use of fertility variation (i.e., CV, Ψ), Person’s product-moment correlation (r), and effective number of parents (Np) as tools for gauging gene diversity of seed crops in production populations. For increasing Np and gene diversity, additional management options such as mixing seed-lots, equal cone harvest and application of supplemental-mass-pollination are recommended.

Download Full-text

Gender, reproductive output covariation and their role on gene diversity of Pinus koraiensis seed orchard crops

10.21203/rs.3.rs-24844/v1 ◽

2020 ◽

Author(s):

Kyu-Suk Kang ◽

Ji-Min Park ◽

Hye-In Kang ◽

Da-Bin Yeom ◽

Yousry A. El-Kassaby ◽

...

Keyword(s):

Gene Diversity ◽

Fundamental Equation ◽

Seed Orchard ◽

Pinus Koraiensis ◽

Effective Number ◽

Effective Population ◽

Management Options ◽

Fertility Variation ◽

Census Number ◽

Seed Crops

Abstract Background: Gender and fertility variation have an impact on mating dynamics in a population because they affect the gene exchange among parental members and the genetic composition of the resultant seed crops. Fertility is the proportional gametic contribution of parents to their progeny. An effective number of parents, derivative of effective population size, is the probability that two alleles randomly chosen from the gamete gene pool originated from the same parent. The effective number of parents is directly related to the fertility variation among parents, which should be monitored for manipulating gene diversity of seed crops. We formulated a fundamental equation of estimating the effective number of parents and applied it to a seed production population.Results: Effective number of parents (Np) was derived from fertility variation (Y) considering covariance (correlation coefficient, r) between maternal and paternal fertility. The Y was calculated from the coefficient of variation in reproductive outputs and divided into female (yf) and male (ym) fertility variation in the population under study. The Np was estimated from the parental Y estimated by the fertility variation of maternal (yf) and paternal (ym) parents. The gene diversity of seed crops was monitored by Y and Np. in a 1.5 generation Pinus koraiensis seed orchard as a case of monoecious species. A large variation of female and male strobili production was observed among the studied 52 parents for four consecutive years, showing statistically significant across all studied years. Parental balance curve showed greater distortion in paternal parents than maternal parents. The Y ranged from 1.879 to 4.035 with greater ym than yf, and the Np varied from 14.8 to 36.8. When pooled, the relative effective number of parents was improved as 80.0% of the census number. Conclusions: We recommend the use of fertility variation (i.e., CV, Y), Person’s product-moment correlation (r) and effective number of parents (Np) as tools for gauging gene diversity of seed crops in production populations. For increasing Np and gene diversity, additional management options such as mixing seed-lots, equal cone harvest and application of supplemental-mass-pollination are recommended.

Download Full-text

Impact of fertility variation on genetic diversity and phenotypic traits in second generation seed production areas and clonal seed orchards of Eucalyptus camaldulensis

Silvae Genetica ◽

10.2478/sg-2019-0006 ◽

2019 ◽

Vol 68 (1) ◽

pp. 29-40

Author(s):

P.G. Suraj ◽

K. Nagabhushana ◽

R. Kamalakannan ◽

M. Varghese

Keyword(s):

Genetic Diversity ◽

Population Size ◽

Effective Population Size ◽

Second Generation ◽

Gene Diversity ◽

Eucalyptus Camaldulensis ◽

Phenotypic Traits ◽

Effective Population ◽

Fertility Variation ◽

The Impact

Abstract Fertility and gene diversity were estimated in three second generation (F2) seed stands (SPA 1-3) and two clone trials (CSO 1&2) of Eucalyptus camaldulensis to assess the impact on seed crop. F2 seedlots were evaluated in comparison to native provenances, ten commercial clones and interspecific hybrids at diverse sites. SPA 1&2 were genetic gain trials of five first generation (F1) orchard seedlots, SPA 3 a plantation of one F1 orchard seedlot, and CSOs were clone trials of 21 commercial clones established at two contrasting sites. Fertility variation, as indicated by sibling coefficient, was high (Ψ, 9-14) in the SPAs as only about 26 % trees were fertile compared to 81 % trees in CSOs. Effective population size was higher in SPA 1 and 2 (Ns, 95 and 74, respectively) than SPA 3 (Ns = 39). Fertility was highly skewed in CSO 2 resulting in low effective population size (Ns = 2) compared to CSO 1 (Ns = 11). Constant seed collection enabled 3-fold increase in relative population size and 22 % higher predicted gene diversity in CSO 2. Genetic diversity (He) estimated using SSR markers was higher in SPA 1&2 and native provenances (NAT), compared to SPA 3 and CSO 1, whereas CSO 2 and clones had lower values. There was a high positive correlation between estimated He and predicted gene diversity values of SPAs and CSOs. He was positively correlated to mean field survival and negatively correlated to kraft pulp yield (KPY), evaluated at three years in progeny trials across three locations. Number of alleles per locus was higher in SPAs and native provenances compared to CSOs and clones. Discriminant principal component analysis clustered CSO, NAT and SPA seedlots in different groups while commercial E. camaldulensis clones clustered close to NAT. Multilocus outcrossing rate was generally high (tm, 91-100 %), though selfing was observed in two families of SPA 3 and CSO 2. Selected interspecific hybrid families of commercial E. camaldulensis clones (with E. urophylla and E. pellita) evaluated at two of the sites had higher He and KPY than clones at three years.

Download Full-text

Variation in Clone Fertility and its Effect on the Gene Diversity of Seeds From a Seed Orchard of Chamaecyparis obtusa in Korea

Silvae Genetica ◽

10.1515/sg-2007-0020 ◽

2007 ◽

Vol 56 (1-6) ◽

pp. 134-137 ◽

Cited By ~ 3

Author(s):

K. S. Kang ◽

T. J. Mullin

Keyword(s):

Gene Diversity ◽

Seed Orchard ◽

Chamaecyparis Obtusa ◽

Clonal Seed Orchard ◽

Fertility Variation ◽

The Status ◽

Status Number ◽

Census Number ◽

One Year ◽

Male Strobilus

Abstract Male and female strobilus production was assessed annually over a four-year period for a clonal seed orchard of hinoki (Chamaecyparis obtusa Endl.) in Korea. Clonal fertility and fertility variation, expressed by both sibling coefficient and coefficient of variation in strobilus production among 50 orchard clones, were reported. Fertility varied among clones and among years producing four-year averages per ramet of 510.2 and 1050.6 for female and male strobili, respectively. The correlation between female and male strobilus production was positive in each of the four years studied and, with the exception of one year, statistically significant. The clonal status number (Ns), a measure of gene diversity, was calculated based on the observed clonal fertility variation and varied from 28.0 (N = 50) in the poorest flowering year (2002) to 46.7 in the best year (2005). On average (pooled), the relative status number was 95% of the census number (N). Variation in female fertility was generally higher than that for male fertility, and this variation was reflected in the status numbers of female and male parents. The pooled Ns estimated from all four years was higher than that for any single year, implying that gene diversity would increase when seeds collected from different years are pooled. Sexual asymmetry calculations showed that clonal contributions would be balanced between genders.

Download Full-text