A total of 24 candidate plus trees（CPTs） of Pongamia pinnata（L.） Pierre.were selected to elucidate their variation and diversity based on thirteen quantitative traits（4 pod traits,6 seed traits of parent trees an...A total of 24 candidate plus trees（CPTs） of Pongamia pinnata（L.） Pierre.were selected to elucidate their variation and diversity based on thirteen quantitative traits（4 pod traits,6 seed traits of parent trees and 3 progeny traits） at Forest Research Centre,Institute of Forest Productivity-Mandar,Ranchi district during 2005-2007.The results show that,CPT-19 had maximum for seven traits viz,pod length（65.6 mm）,100-pod weight（542.4 g）,seed 2D（two dimension） area（351.2 mm2）,seed length（27.9 mm）,seed breadth（17.4 mm）,100-seed weight（217.9 g） and plant height（164.3 cm）.The traits,100-pod weight and 100-seed weight had a high heritability（98.4%,96.9%） accompanied with high genetic advance（46.0%,34.9%）.There is a positive significant correlation between 100-pod weight and 100-seed weight traits at both genotypic and phenotypic levels with plant height,collar diameter and volume index at 30 MAS（months after sowing）.Volume index expressed a moderate heritability（47.4%） accompanied with high genetic advance（48.4%）,indicating that the character is governed by additive gene effects.In divergence study,24 accessions were grouped into 6 clusters on the basis of non-hierarchical euclidian cluster analysis.The genotypes in cluster IV（CPT-5,CPT-6,CPT-7,CPT-12,CPT-16,CPT18,CPT-22） and cluster III（CPT-4,CPT-8,CPT-9,CPT-20,CPT-21） were most heterogeneous and can be best used within group hybridization.The wide diversity exists between the cluster V and II,followed by cluster II and I and crosses between CPTs of these clusters may result in substantial segregates.It is revealed that the existence of substantial variation and diversity can be utilized for genetic resource conservation and further tree improvement programmers of the species.展开更多
Seeds of Acacia species and subspecies were characterized using an image analyzer and discriminated for the purpose of identification of species, using their seeds. The species considered in the study were Acacia nilo...Seeds of Acacia species and subspecies were characterized using an image analyzer and discriminated for the purpose of identification of species, using their seeds. The species considered in the study were Acacia nilotica subsp. indica, A. nilotica subsp. cupressiformis, A. nilotica subsp. tomentosa, A. tortilis subsp. raddiana, A. tortilis subsp. spirocarpa, A. raddiana, A. senegal, A. auriculiformis, A. farnesiana, A. leucophloea, A. mearnsii, A. melanoxylon, A. planifrons and A. mangium. Eight samples each consisting of 25 seeds per species were studied using the image analyzer for physical characteristics of seeds, such as 2D surface area, length, width, perimeter, roundness, aspect ratio and fullness ratio. Discriminant analysis showed that acacias can be discriminated at species and subspecies levels, with 96% accuracy. Exceptions were A. nilotica subsp. tomentosa(75.0%), A. tortilis subsp. spirocarpa(75.0%) and A. raddiana(87.5%) which had relatively low discrimination accuracy. However, discriminant analysis within selected species showed complete recognition of these species except for A. tortilis subsp. spirocarpa, that had still a large overlap with A. leucophloea. The study also revealed that both seed size and shape characteristics were responsible for species discrimination. It can be concluded that rapid analysis of seed size and shape characteristics using image analysis techniques can be used as primary and secondary keys for identification of acacias.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
文摘A total of 24 candidate plus trees（CPTs） of Pongamia pinnata（L.） Pierre.were selected to elucidate their variation and diversity based on thirteen quantitative traits（4 pod traits,6 seed traits of parent trees and 3 progeny traits） at Forest Research Centre,Institute of Forest Productivity-Mandar,Ranchi district during 2005-2007.The results show that,CPT-19 had maximum for seven traits viz,pod length（65.6 mm）,100-pod weight（542.4 g）,seed 2D（two dimension） area（351.2 mm2）,seed length（27.9 mm）,seed breadth（17.4 mm）,100-seed weight（217.9 g） and plant height（164.3 cm）.The traits,100-pod weight and 100-seed weight had a high heritability（98.4%,96.9%） accompanied with high genetic advance（46.0%,34.9%）.There is a positive significant correlation between 100-pod weight and 100-seed weight traits at both genotypic and phenotypic levels with plant height,collar diameter and volume index at 30 MAS（months after sowing）.Volume index expressed a moderate heritability（47.4%） accompanied with high genetic advance（48.4%）,indicating that the character is governed by additive gene effects.In divergence study,24 accessions were grouped into 6 clusters on the basis of non-hierarchical euclidian cluster analysis.The genotypes in cluster IV（CPT-5,CPT-6,CPT-7,CPT-12,CPT-16,CPT18,CPT-22） and cluster III（CPT-4,CPT-8,CPT-9,CPT-20,CPT-21） were most heterogeneous and can be best used within group hybridization.The wide diversity exists between the cluster V and II,followed by cluster II and I and crosses between CPTs of these clusters may result in substantial segregates.It is revealed that the existence of substantial variation and diversity can be utilized for genetic resource conservation and further tree improvement programmers of the species.
基金the Swedish International Development Cooperation Agency and Swedish Research Counsil for providing financial support through the Swedish Research Link Program
文摘Seeds of Acacia species and subspecies were characterized using an image analyzer and discriminated for the purpose of identification of species, using their seeds. The species considered in the study were Acacia nilotica subsp. indica, A. nilotica subsp. cupressiformis, A. nilotica subsp. tomentosa, A. tortilis subsp. raddiana, A. tortilis subsp. spirocarpa, A. raddiana, A. senegal, A. auriculiformis, A. farnesiana, A. leucophloea, A. mearnsii, A. melanoxylon, A. planifrons and A. mangium. Eight samples each consisting of 25 seeds per species were studied using the image analyzer for physical characteristics of seeds, such as 2D surface area, length, width, perimeter, roundness, aspect ratio and fullness ratio. Discriminant analysis showed that acacias can be discriminated at species and subspecies levels, with 96% accuracy. Exceptions were A. nilotica subsp. tomentosa(75.0%), A. tortilis subsp. spirocarpa(75.0%) and A. raddiana(87.5%) which had relatively low discrimination accuracy. However, discriminant analysis within selected species showed complete recognition of these species except for A. tortilis subsp. spirocarpa, that had still a large overlap with A. leucophloea. The study also revealed that both seed size and shape characteristics were responsible for species discrimination. It can be concluded that rapid analysis of seed size and shape characteristics using image analysis techniques can be used as primary and secondary keys for identification of acacias.
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.
