In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducte...In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducted at the Central Agricultural Research Institute, Port Blair during 2010 to 2011. The variability studies for pod and seed traits revealed that, the accession CPT-6 collected from New Wandoor in South Andaman recorded the maximum values for eight traits viz. pod length （75.51 mm）, pod width （34.62 mm）, pod thickness （17.55 mm）, 100 pod weight （770.33 g）, seed width （21.23 mm）, 100 seed weight （377.00 g）, oil percentage （43.92%） and germination percentage （94.7%）. However, the maximum seed length （26.46 mm） was recorded from CPT 2 and the maximum pod-seed ratio was obtained from CPT 13 and CPT 4 （2.50 and 2.44 respectively）. The phenotypic and genotypic coefficients of variations were also close to each other for all traits, but the 100 pod and seed weight exhibited higher phenotypic and genotypic coefficient of variation than the other traits. Estimates of broad sense heritability ranged from 0.30 （for seed length） to 0.95 （pod length） and genetic ad- vance as percent of the mean ranged between 11.66% and 57.40% with seed length giving the lowest value and 100 pod weight giving the high- est value. Both the phenotypic and genotypic correlation between pod length, pod width, pod thickness, 100 pod weight, seed width and 100 seed weight and between pod thickness, 100 pod weight, seed width, 100 seed weight and germination percentage were found to be strong. On the basis of non hierarchical Euclidian cluster analysis, 24 accessions were grouped into six clusters. The maximum numbers of seven accessions were included in cluster VI. The maximum intra cluster distance （10.238）shown by cluster VI and the maximum inter cluster distance （17.021） between V and HI followed by III and II （15.942）. Among the six clus- ters formed the cluster III recorded maximum oil percentage, 100 pod weight, 100 seed ,weight, pod length, pod thickness, pod width, seed width and. germination percentage, while cluster V recorded maximum pod seed ratio and germination percentage. The present findings suggest that the crossing between accessions of cluster V and cluster III will result in a wide spectrum of variability in subsequent generations.展开更多
A field trial of 20 seed sources of Asparagus racemosus was conducted at the Forest Research Institute, Dehradun, Uttarakhand, India to evaluate their performance of different economic traits. Genotypic variance, phen...A field trial of 20 seed sources of Asparagus racemosus was conducted at the Forest Research Institute, Dehradun, Uttarakhand, India to evaluate their performance of different economic traits. Genotypic variance, phenotypic variance, genotypic coefficient of variance （GCV） and phenotypic coefficient of variance （PCV） for number of shoots, shoot height, shoot weight, number of roots, root length, root diameter and root weight were calculated. Maximum genotypic and phenotypic variance was observed in shoot height among the shoot - related traits and root length among the root - related traits. For the shoot height, genotypic variance, phenotypic variance, genotypic coefficient of variance, phenotypic coefficient of variance were 231.80, 3924.80, 61.26 and 1037.32, respectively, where those of the root length were 9.55, 16.80, 23.46 and 41.27, respectively. The maximum genetic advance and genetic gain were obtained for shoot height among the shoot-related traits and root length among the root-related traits. Index values were developed for all the seed sources based on the four most important traits, and Panthnagar （Uttrakhand）, Jodhpur （Rajasthan）, Dehradun （Uttarakhand）, Chandigarh （Punjab）, Jammu （Jammu and Kashmir） and Solan （Himachal Pradesh）, were promising seed sources for root production.展开更多
Investigations were made to determine the nature and extent of variations present for 10 morphological characters of cone,seed and seedlings of 17 plus trees（PTs）of Pinus kesiya growing in eastern Himalayas（Meghala...Investigations were made to determine the nature and extent of variations present for 10 morphological characters of cone,seed and seedlings of 17 plus trees（PTs）of Pinus kesiya growing in eastern Himalayas（Meghalaya state） of India.The significant variations has been observed in cone weight,cone length,cone diameter,seed length,seed diameter,seed weight,number of seeds per cone,seed germination,seedling height and seedling collar diameter among different PTs of the species.Significant positive correlation（p ／ 0.01） between seed weight,cone length and cone diameter showed that seed weight in P.kesiya depend more on the cone size.Seed germination is found positively correlated（p ／ 0.01） with seed weight,seed diameter,cone size and number of seeds per cone in the study.Among geographical factors,latitude and altitude are found positively correlated（p ／ 0.05） with cone weight and seed diameter,respectively.The genetic parameters for seed,cone and seedlings of PTs of P.kesiya also showed a wide range of variability in terms of variance,coefficient of variability,broad sense heritability,genetic advance and genetic gain.Seed weight,seeds per cone and seedling diameter showed high heritability values（[75） coupled with maximum genetic gain.Traits with such values indicate the presence of good amount of heritable additive components and are under strong genetic control.The findings of the study revealed that PTs expressed both phenotypic and genotypic differences in the seed,cone and seedling characters,which may be attributed to the differences in genetic makeup of various PTs and environmental factors i.e.genotypic and environmental interaction.The presence of high variability in P.kesiya PTs for different characters provide further opportunities to improve the population in subsequent generations so as to establish this species as an important timber tree to be grown on less fertile and degraded soils in its distributional ranges.展开更多
We analyzed 17 seed sources （seed stands） ofPinus wallichiana for variations present in cone and seed characters, scattered over natural distribution in north-west Himalayan states （Uttarakhand and Himachal Pradesh...We analyzed 17 seed sources （seed stands） ofPinus wallichiana for variations present in cone and seed characters, scattered over natural distribution in north-west Himalayan states （Uttarakhand and Himachal Pradesh） of India. The significant variations were observed in cone weight, cone length, cone width, seed length, seed width, seed weight, seed germination, radicle length, and plumule length among different seed sources of the species. Significant positive correlation between seed weight, cone weight and cone width showed that seed weight in the species depend more on the cone size. Seed germination was also positively correlated with seed weight, cone weight and radicle length in the study. The estimates of variability with regard to genetic parameters for seed weight, seed germination, cone length, cone width, cone weight showed wide range of variation in the study. Seed weight showed high heritability values coupled with maximum genetic gain. Traits with such values indicate presence of good amount of heritable additive components and are under strong genetic control. The findings of the study revealed that seed sources expressed both phenotypic and genotypic differences in the seed and cone traits which might be due to the differences in genetic make up of various seed sources and environmental factors i,e. genotypic and environmental interaction, The study suggests that the seed weight should be given the top priority for the further improvement of this species.展开更多
On the basis of the results from the geographic provenance test of nine years old /arix olgensis in Liangshui Natural Reserve of our university, a study on the geographic varition and the primary selection of the best...On the basis of the results from the geographic provenance test of nine years old /arix olgensis in Liangshui Natural Reserve of our university, a study on the geographic varition and the primary selection of the best provenance of torix oIgensis was carried out. The main results are as follows: 1. The different provenances of Larix olgensis have rich and wide genetic variation, and exist a linear correlation with latitude and longitude in collection area. General trends are enumerated below: Provenances at lower latitude and more west longitude have lighter thousand seed weight. short growth period, higher increment, wide branches, rich leaves and crown as well as worst adaptabi llity. It is a dual-way variation along with two directions of latitude and longitude, and also embodies a change gradually in climate condition from south to north. The temperat ures in seed production site, especially the mean temperature in January and≥10℃ accumulated temperature, are important factors that produce geographic variation for larix olgensis. 2. The variation of different provenances in periodic biological phenomena and growth rhythm trends are that: ① both of the provenances from Changbai Mt. (Ⅲ) and Dashitou(Ⅳ) at low latitude belong to the centralized growth type, and have shout growth period, the difference between these two provenances is that the provenance from Changbai Mt. grows well in all time, Dashitou provennce is well only in later period; ②the provenance from Baidao Mt. (Ⅱ) at middle latitude belongs to even growth type and has longer grpwth period, this provenance has higher increment in early and later periods relatively; ③ Xiaobeihu provenance at high latitude is a growth type among Ⅱ Ⅲ and Ⅳ provenances and has a general growth period, the provenance grows better in middle time and worse in later time. 3. The best provenance in Liangshui Natural Reserve and its meighbourhood is Dashitou Procenance. which growth in height. diameter and volume has exceeded 16. 28%, 46. 27%, 30. 58%, 78. 20, 82. 00% as well as 392. 00% by comparison with the mean value of the contrast and the worst provenance respectively, The result from the height growth of three, five. seven and nine years old Larix olgensis by using the method of order correlation analysis demonstrates that it is possible to make early selection of the provenance. Meanwhile. data from juvenile and mature of larix olgensis plantation also prove the reliability of the early selection. 4. The provenance heritabilities of nine years old larix olgensis in Liangshui Natural Reserve are follows:The heritability of the height growth (h2)is 0. 79; The heritability of the diameter breast height (h2) is 0. 791; The geretic gain is 24. 5%and 40. 36% respectively.展开更多
Improvement in seed and seedling quality of Acacia auriculiformis after culling phenotypically inferior trees was studied in a 6-year old seed production area （SPA）. A 5-ha plantation was identified, of which 2.3 ha...Improvement in seed and seedling quality of Acacia auriculiformis after culling phenotypically inferior trees was studied in a 6-year old seed production area （SPA）. A 5-ha plantation was identified, of which 2.3 ha was converted into SPA. The initial stocking, 1 612 trees·ha^-1, was thinned down to 982 trees·ha^-1 based on growth characteristics. The following fruiting season, seeds were collected from 10 randomly selected trees in culled and non-culled stands, and seed physical characters, germination and seedling traits were assessed. Seed weight, seed thickness and percentage germination increased by 32.1%, 4.43% and 22.37%, respectively in the culled stand compared to the non-culled stand. Culling also increased the speed of germination, seedling dry weight and seedling vigor index. Heritability values were high for seed weight （0.974） and seed thickness （0.948） while medium values were observed for percentage germination （0.577） and total dry weight （0.534）. Predicted genetic gain was 11.13% and 11.22% for seed weight and percentage germination, respectively. The actual gain was 32.1, 51.9 and 22.9% for seed weight, percentage germination and total dry matter, respectively. In conclusion, SPAs established by culling inferior trees could serve as sources of good quality seeds for reforestation programs until genetically improved seeds are made available.展开更多
This paper summarizes the result from the provenance test of eight years old Pinus sylvestris var. mongolica in Liangshui Natural Rcserve comprehensivcly. The main contents include:(1) the geographic variation of the ...This paper summarizes the result from the provenance test of eight years old Pinus sylvestris var. mongolica in Liangshui Natural Rcserve comprehensivcly. The main contents include:(1) the geographic variation of the growth characters of Pinus sylvestris var.mongolica.tends to negative change gradually at latitude and has obvious climatic nature, (2) no significant difference exists in the morphological adaptability and resistant characteristics and so on; (3)on the basis of the geographic variation study on the growth characteristics, the provcnances of Pinus sylvestris var. mongolica were classificd into two geographic populations and two subpopulations as follows:the northern population of the Daxing'an Mountain (Ⅰ) and the southern population of the Daxing'an Mountain as wcll as the Xiaoxinglan Mountain (Ⅱ),which includcs Honghuarii subpopulation and Kalunshan subpopulation (Ⅱ-2). (4) the height growth rhythm was analyzed according to the divided population and subpopuIation; (5) the best provcnance was selected for the Liangshui Natural Rescrve and its neighborhood accord ing to the results from SSR test of the growth characteristics (the breast height diameter and height of eight year old trces), the possibility of the carly provcnance sclection was also verified by the method of order correlation analysis on the height growth of three. five, scvcn and eight years old provenances.展开更多
Eighteen clones of Eucalyptus tereticornis （Sm.） were evaluated for three years by adopting randomized block design for various growth parameters at Hoshiarpur, Punjab, India and compared with two checks. Significan...Eighteen clones of Eucalyptus tereticornis （Sm.） were evaluated for three years by adopting randomized block design for various growth parameters at Hoshiarpur, Punjab, India and compared with two checks. Significant variations were recorded for height, diameter at breast height （DBH） and clear bole height （CBH）. The broad sense heritability was low to moderate for both height and CBH. The genetic gain for height and CBH increased substantially pe se with the increase in age of trees. The average genetic gain for thres years was recorded maximum for height （159.60%） followed by DBH （110.97%） and CBH （70.34%）. Clone 17 attained maximum DBH over other genotypes for second and third year followed by clones 14 and 11. Clone 5 showed an upward trend for DBH and maintained its superiority for CBH as the age of the tree increased. Similarly, clone 11 changed its ranking from 9th to 8th to 3rd for DBH and from 9th to 4th to 2nd for CBH, respectively for the age of one, two and three years. Nonetheless, clones 6 and 10 per- formed poorly for all the characters studied. Clones 17, 14 and 5 were found to be the most promising clones for commercial deployment.展开更多
In order to quantify within-and between-population variation in seed and seedling traits of Juglans mandshurica and reveal the relationship among genetic and environmental variations and select elite families,samples ...In order to quantify within-and between-population variation in seed and seedling traits of Juglans mandshurica and reveal the relationship among genetic and environmental variations and select elite families,samples of 50 J.mandshurica families from five natural populations in Liaoning Province,northeast China,were taken to measure seed and seedling traits.The results show that all seed traits varied significantly among families within the population,but only kernel weight and kernel rate showed significant variations among populations.Average values of single seed weight,length,width,lateral diameter,and average size,and kernel weight and rate were 10.1 g,43.0 mm,29.2 mm,28.1 mm,33.4 mm,and 2.2 g and 22.5%,respectively.Significant variations were observed in seedling height and root collar diameter among families and interaction between families and blocks,but the block effects on height and root collar diameter were insignificant.Average values of height and root collar diameter were 94.0 cm and 8.7 mm,respectively.Family heritability of traits ranged from 0.6 gm(kernel weight)to 0.9 mm(seedling height).Correlation analysis showed a strong relationship among seed traits but a weak correlation between seed and seedling traits.Cluster analysis grouped the five natural populations of J.mandshurica into three significant clusters with different characteristics.The general combining ability analysis showed that most traits in one family(WD11)were higher,suggesting parental traits were excellent for selecting elite parent clones.Using the comprehensive evaluation method,five families with better seed traits and five families with better seedling traits were selected as elite materials with 10%selection rate.The genetic gains of these elite materials for seed weight,kernel weight,average seed size,kernel rate,seedling height,and root collar diameter were 13.1%,10.3%,4.1%,2.4%,29.7%,and 21.1%,respectively.展开更多
The study of genetic variability is a prerequisite for any tree improvement program. Screening of clones showing the effect of dominance in growth and tree form is essential to identify productive clones, matched to s...The study of genetic variability is a prerequisite for any tree improvement program. Screening of clones showing the effect of dominance in growth and tree form is essential to identify productive clones, matched to sites. Our study performed in a clonal seed orchard at Lacchiwala of India, represented by 31 clones of Dalbergia sissoo （Shisham） Roxb. from diverse locations revealed significant variability at the 0.1% level of significance in various morphological traits. At the age of 13 years, clone 196 （Gonda） revealed maximum height of 20.2 m and a girth at breast height of 74.2 cm. The five identified clones viz. 196, 198, 192, 123 and 235 were well adapted to the climatic conditions of this zone, hence survived well and showed good performance compared to other clones. Heritability estimates of 87%, 83% and 80% for height, crown width and crown length respectively coupled with high genetic gains indicated strong genetic control of these variables. A correlation matrix of various growth attributes revealed positive correlation among these attributes. On the basis of the entire set of growth variables, the clones were grouped into two major clusters with three subgroups.展开更多
基金financially supported by the National Oil Seeds and Vegetable Oils Development Board,Gurgaon,Ministry of Agriculture,Government of India
文摘In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducted at the Central Agricultural Research Institute, Port Blair during 2010 to 2011. The variability studies for pod and seed traits revealed that, the accession CPT-6 collected from New Wandoor in South Andaman recorded the maximum values for eight traits viz. pod length （75.51 mm）, pod width （34.62 mm）, pod thickness （17.55 mm）, 100 pod weight （770.33 g）, seed width （21.23 mm）, 100 seed weight （377.00 g）, oil percentage （43.92%） and germination percentage （94.7%）. However, the maximum seed length （26.46 mm） was recorded from CPT 2 and the maximum pod-seed ratio was obtained from CPT 13 and CPT 4 （2.50 and 2.44 respectively）. The phenotypic and genotypic coefficients of variations were also close to each other for all traits, but the 100 pod and seed weight exhibited higher phenotypic and genotypic coefficient of variation than the other traits. Estimates of broad sense heritability ranged from 0.30 （for seed length） to 0.95 （pod length） and genetic ad- vance as percent of the mean ranged between 11.66% and 57.40% with seed length giving the lowest value and 100 pod weight giving the high- est value. Both the phenotypic and genotypic correlation between pod length, pod width, pod thickness, 100 pod weight, seed width and 100 seed weight and between pod thickness, 100 pod weight, seed width, 100 seed weight and germination percentage were found to be strong. On the basis of non hierarchical Euclidian cluster analysis, 24 accessions were grouped into six clusters. The maximum numbers of seven accessions were included in cluster VI. The maximum intra cluster distance （10.238）shown by cluster VI and the maximum inter cluster distance （17.021） between V and HI followed by III and II （15.942）. Among the six clus- ters formed the cluster III recorded maximum oil percentage, 100 pod weight, 100 seed ,weight, pod length, pod thickness, pod width, seed width and. germination percentage, while cluster V recorded maximum pod seed ratio and germination percentage. The present findings suggest that the crossing between accessions of cluster V and cluster III will result in a wide spectrum of variability in subsequent generations.
文摘A field trial of 20 seed sources of Asparagus racemosus was conducted at the Forest Research Institute, Dehradun, Uttarakhand, India to evaluate their performance of different economic traits. Genotypic variance, phenotypic variance, genotypic coefficient of variance （GCV） and phenotypic coefficient of variance （PCV） for number of shoots, shoot height, shoot weight, number of roots, root length, root diameter and root weight were calculated. Maximum genotypic and phenotypic variance was observed in shoot height among the shoot - related traits and root length among the root - related traits. For the shoot height, genotypic variance, phenotypic variance, genotypic coefficient of variance, phenotypic coefficient of variance were 231.80, 3924.80, 61.26 and 1037.32, respectively, where those of the root length were 9.55, 16.80, 23.46 and 41.27, respectively. The maximum genetic advance and genetic gain were obtained for shoot height among the shoot-related traits and root length among the root-related traits. Index values were developed for all the seed sources based on the four most important traits, and Panthnagar （Uttrakhand）, Jodhpur （Rajasthan）, Dehradun （Uttarakhand）, Chandigarh （Punjab）, Jammu （Jammu and Kashmir） and Solan （Himachal Pradesh）, were promising seed sources for root production.
基金funded by Indian Council of Forestry and Education,Dehradun
文摘Investigations were made to determine the nature and extent of variations present for 10 morphological characters of cone,seed and seedlings of 17 plus trees（PTs）of Pinus kesiya growing in eastern Himalayas（Meghalaya state） of India.The significant variations has been observed in cone weight,cone length,cone diameter,seed length,seed diameter,seed weight,number of seeds per cone,seed germination,seedling height and seedling collar diameter among different PTs of the species.Significant positive correlation（p ／ 0.01） between seed weight,cone length and cone diameter showed that seed weight in P.kesiya depend more on the cone size.Seed germination is found positively correlated（p ／ 0.01） with seed weight,seed diameter,cone size and number of seeds per cone in the study.Among geographical factors,latitude and altitude are found positively correlated（p ／ 0.05） with cone weight and seed diameter,respectively.The genetic parameters for seed,cone and seedlings of PTs of P.kesiya also showed a wide range of variability in terms of variance,coefficient of variability,broad sense heritability,genetic advance and genetic gain.Seed weight,seeds per cone and seedling diameter showed high heritability values（[75） coupled with maximum genetic gain.Traits with such values indicate the presence of good amount of heritable additive components and are under strong genetic control.The findings of the study revealed that PTs expressed both phenotypic and genotypic differences in the seed,cone and seedling characters,which may be attributed to the differences in genetic makeup of various PTs and environmental factors i.e.genotypic and environmental interaction.The presence of high variability in P.kesiya PTs for different characters provide further opportunities to improve the population in subsequent generations so as to establish this species as an important timber tree to be grown on less fertile and degraded soils in its distributional ranges.
基金financially supported by USDA, Washington for conducting this study under the project "Studies on Himalayan Pines" (1996-2006)
文摘We analyzed 17 seed sources （seed stands） ofPinus wallichiana for variations present in cone and seed characters, scattered over natural distribution in north-west Himalayan states （Uttarakhand and Himachal Pradesh） of India. The significant variations were observed in cone weight, cone length, cone width, seed length, seed width, seed weight, seed germination, radicle length, and plumule length among different seed sources of the species. Significant positive correlation between seed weight, cone weight and cone width showed that seed weight in the species depend more on the cone size. Seed germination was also positively correlated with seed weight, cone weight and radicle length in the study. The estimates of variability with regard to genetic parameters for seed weight, seed germination, cone length, cone width, cone weight showed wide range of variation in the study. Seed weight showed high heritability values coupled with maximum genetic gain. Traits with such values indicate presence of good amount of heritable additive components and are under strong genetic control. The findings of the study revealed that seed sources expressed both phenotypic and genotypic differences in the seed and cone traits which might be due to the differences in genetic make up of various seed sources and environmental factors i,e. genotypic and environmental interaction, The study suggests that the seed weight should be given the top priority for the further improvement of this species.
文摘On the basis of the results from the geographic provenance test of nine years old /arix olgensis in Liangshui Natural Reserve of our university, a study on the geographic varition and the primary selection of the best provenance of torix oIgensis was carried out. The main results are as follows: 1. The different provenances of Larix olgensis have rich and wide genetic variation, and exist a linear correlation with latitude and longitude in collection area. General trends are enumerated below: Provenances at lower latitude and more west longitude have lighter thousand seed weight. short growth period, higher increment, wide branches, rich leaves and crown as well as worst adaptabi llity. It is a dual-way variation along with two directions of latitude and longitude, and also embodies a change gradually in climate condition from south to north. The temperat ures in seed production site, especially the mean temperature in January and≥10℃ accumulated temperature, are important factors that produce geographic variation for larix olgensis. 2. The variation of different provenances in periodic biological phenomena and growth rhythm trends are that: ① both of the provenances from Changbai Mt. (Ⅲ) and Dashitou(Ⅳ) at low latitude belong to the centralized growth type, and have shout growth period, the difference between these two provenances is that the provenance from Changbai Mt. grows well in all time, Dashitou provennce is well only in later period; ②the provenance from Baidao Mt. (Ⅱ) at middle latitude belongs to even growth type and has longer grpwth period, this provenance has higher increment in early and later periods relatively; ③ Xiaobeihu provenance at high latitude is a growth type among Ⅱ Ⅲ and Ⅳ provenances and has a general growth period, the provenance grows better in middle time and worse in later time. 3. The best provenance in Liangshui Natural Reserve and its meighbourhood is Dashitou Procenance. which growth in height. diameter and volume has exceeded 16. 28%, 46. 27%, 30. 58%, 78. 20, 82. 00% as well as 392. 00% by comparison with the mean value of the contrast and the worst provenance respectively, The result from the height growth of three, five. seven and nine years old Larix olgensis by using the method of order correlation analysis demonstrates that it is possible to make early selection of the provenance. Meanwhile. data from juvenile and mature of larix olgensis plantation also prove the reliability of the early selection. 4. The provenance heritabilities of nine years old larix olgensis in Liangshui Natural Reserve are follows:The heritability of the height growth (h2)is 0. 79; The heritability of the diameter breast height (h2) is 0. 791; The geretic gain is 24. 5%and 40. 36% respectively.
文摘Improvement in seed and seedling quality of Acacia auriculiformis after culling phenotypically inferior trees was studied in a 6-year old seed production area （SPA）. A 5-ha plantation was identified, of which 2.3 ha was converted into SPA. The initial stocking, 1 612 trees·ha^-1, was thinned down to 982 trees·ha^-1 based on growth characteristics. The following fruiting season, seeds were collected from 10 randomly selected trees in culled and non-culled stands, and seed physical characters, germination and seedling traits were assessed. Seed weight, seed thickness and percentage germination increased by 32.1%, 4.43% and 22.37%, respectively in the culled stand compared to the non-culled stand. Culling also increased the speed of germination, seedling dry weight and seedling vigor index. Heritability values were high for seed weight （0.974） and seed thickness （0.948） while medium values were observed for percentage germination （0.577） and total dry weight （0.534）. Predicted genetic gain was 11.13% and 11.22% for seed weight and percentage germination, respectively. The actual gain was 32.1, 51.9 and 22.9% for seed weight, percentage germination and total dry matter, respectively. In conclusion, SPAs established by culling inferior trees could serve as sources of good quality seeds for reforestation programs until genetically improved seeds are made available.
文摘This paper summarizes the result from the provenance test of eight years old Pinus sylvestris var. mongolica in Liangshui Natural Rcserve comprehensivcly. The main contents include:(1) the geographic variation of the growth characters of Pinus sylvestris var.mongolica.tends to negative change gradually at latitude and has obvious climatic nature, (2) no significant difference exists in the morphological adaptability and resistant characteristics and so on; (3)on the basis of the geographic variation study on the growth characteristics, the provcnances of Pinus sylvestris var. mongolica were classificd into two geographic populations and two subpopulations as follows:the northern population of the Daxing'an Mountain (Ⅰ) and the southern population of the Daxing'an Mountain as wcll as the Xiaoxinglan Mountain (Ⅱ),which includcs Honghuarii subpopulation and Kalunshan subpopulation (Ⅱ-2). (4) the height growth rhythm was analyzed according to the divided population and subpopuIation; (5) the best provcnance was selected for the Liangshui Natural Rescrve and its neighborhood accord ing to the results from SSR test of the growth characteristics (the breast height diameter and height of eight year old trces), the possibility of the carly provcnance sclection was also verified by the method of order correlation analysis on the height growth of three. five, scvcn and eight years old provenances.
文摘Eighteen clones of Eucalyptus tereticornis （Sm.） were evaluated for three years by adopting randomized block design for various growth parameters at Hoshiarpur, Punjab, India and compared with two checks. Significant variations were recorded for height, diameter at breast height （DBH） and clear bole height （CBH）. The broad sense heritability was low to moderate for both height and CBH. The genetic gain for height and CBH increased substantially pe se with the increase in age of trees. The average genetic gain for thres years was recorded maximum for height （159.60%） followed by DBH （110.97%） and CBH （70.34%）. Clone 17 attained maximum DBH over other genotypes for second and third year followed by clones 14 and 11. Clone 5 showed an upward trend for DBH and maintained its superiority for CBH as the age of the tree increased. Similarly, clone 11 changed its ranking from 9th to 8th to 3rd for DBH and from 9th to 4th to 2nd for CBH, respectively for the age of one, two and three years. Nonetheless, clones 6 and 10 per- formed poorly for all the characters studied. Clones 17, 14 and 5 were found to be the most promising clones for commercial deployment.
基金financially supported by Liaoning Academy of Agricultural Sciences Subject Construction Program Project(NO.2019DD217032)。
文摘In order to quantify within-and between-population variation in seed and seedling traits of Juglans mandshurica and reveal the relationship among genetic and environmental variations and select elite families,samples of 50 J.mandshurica families from five natural populations in Liaoning Province,northeast China,were taken to measure seed and seedling traits.The results show that all seed traits varied significantly among families within the population,but only kernel weight and kernel rate showed significant variations among populations.Average values of single seed weight,length,width,lateral diameter,and average size,and kernel weight and rate were 10.1 g,43.0 mm,29.2 mm,28.1 mm,33.4 mm,and 2.2 g and 22.5%,respectively.Significant variations were observed in seedling height and root collar diameter among families and interaction between families and blocks,but the block effects on height and root collar diameter were insignificant.Average values of height and root collar diameter were 94.0 cm and 8.7 mm,respectively.Family heritability of traits ranged from 0.6 gm(kernel weight)to 0.9 mm(seedling height).Correlation analysis showed a strong relationship among seed traits but a weak correlation between seed and seedling traits.Cluster analysis grouped the five natural populations of J.mandshurica into three significant clusters with different characteristics.The general combining ability analysis showed that most traits in one family(WD11)were higher,suggesting parental traits were excellent for selecting elite parent clones.Using the comprehensive evaluation method,five families with better seed traits and five families with better seedling traits were selected as elite materials with 10%selection rate.The genetic gains of these elite materials for seed weight,kernel weight,average seed size,kernel rate,seedling height,and root collar diameter were 13.1%,10.3%,4.1%,2.4%,29.7%,and 21.1%,respectively.
文摘The study of genetic variability is a prerequisite for any tree improvement program. Screening of clones showing the effect of dominance in growth and tree form is essential to identify productive clones, matched to sites. Our study performed in a clonal seed orchard at Lacchiwala of India, represented by 31 clones of Dalbergia sissoo （Shisham） Roxb. from diverse locations revealed significant variability at the 0.1% level of significance in various morphological traits. At the age of 13 years, clone 196 （Gonda） revealed maximum height of 20.2 m and a girth at breast height of 74.2 cm. The five identified clones viz. 196, 198, 192, 123 and 235 were well adapted to the climatic conditions of this zone, hence survived well and showed good performance compared to other clones. Heritability estimates of 87%, 83% and 80% for height, crown width and crown length respectively coupled with high genetic gains indicated strong genetic control of these variables. A correlation matrix of various growth attributes revealed positive correlation among these attributes. On the basis of the entire set of growth variables, the clones were grouped into two major clusters with three subgroups.
