The ant genus Myopopone Roger is distributed in Oriental and Indo-Australian regions.Only one valid species,M.castanea(Smith),is recognized in the genus up to date.M.castanea(Smith) is recorded in Tibet,China,for ...The ant genus Myopopone Roger is distributed in Oriental and Indo-Australian regions.Only one valid species,M.castanea(Smith),is recognized in the genus up to date.M.castanea(Smith) is recorded in Tibet,China,for the first time.Complete information,including characters of the genus,detailed measurements,descriptions,and illustrations of worker and queen castes of M.castanea,is provided.展开更多
[Objective] The aim was to study the supporting raising technology of Castanea mollissima Blume molecular marker-assisted selection to reduce the cost and time for chestnut breeding.[Method] To find the best cutting m...[Objective] The aim was to study the supporting raising technology of Castanea mollissima Blume molecular marker-assisted selection to reduce the cost and time for chestnut breeding.[Method] To find the best cutting method,10 treatments were designed according to transverse diameter and vertical diameter of the chestnut including different cutting ratios in 1/2,1/3,1/4 and different directions about cross cutting,vertical cutting,bevel cutting and two side-cutting.The germination rate,seedling survival rate and morphological indicators of the treatments were measured;significant difference among them was also analyzed.[Result] 1/3 bevel cutting was the best,which not only could give high germination rate and survival rate,but also could guarantee high quality of nursery stock,which did not grow so differently with the untreated seedlings.[Conclusion] This way can not only reduce too much cost and time for seedling breeding,but also promote the germination of chestnut in advance,which could do much good to production.展开更多
Chinese chestnut is an important nut tree around the world.Although the types of Chinese chestnut resources are abundant,resource utilization and protection of chestnut accessions are still very limited.Here,we finger...Chinese chestnut is an important nut tree around the world.Although the types of Chinese chestnut resources are abundant,resource utilization and protection of chestnut accessions are still very limited.Here,we fingerprinted and determined the genetic relationships and core collections of Chinese chestnuts using 18 fluorescently labeled SSR markers generated from 146 chestnut accessions.Our analyses showed that these markers from the tested accessions are highly polymorphic,with an average allele number(N_(a))and polymorphic information content(PIC)of 8.100 and 0.622 per locus,respectively.Using these strongly distinguishing markers,we successfully constructed unique fingerprints for 146 chestnut accessions and selected seven of the SSR markers as core markers to rapidly distinguish different accessions.Our exploration of the genetic relationships among the five cultivar groups indicated that Chinese chestnut accessions are divided into three regional type groups:group I(North China(NC)and Northwest China(NWC)cultivar groups),group II(middle and lower reaches of the Yangtze River(MLY)cultivar group)and group III(Southeast China(SEC)and Southwest China(SWC)cultivar groups).Finally,we selected 45 core collection members which represent the most genetic diversity of Chinese chestnut accessions.This study provides valuable information for identifying chestnut accessions and understanding the phylogenetic relationships among cultivar groups,which can serve as the basis for efficient breeding in the future.展开更多
A new method CTAB-silica for DNA extraction and purification from the leaves and buds of Castanea mollissima and Ginkgo biloba was tested. The method is based on the silica-based purification protocol developed by Bo...A new method CTAB-silica for DNA extraction and purification from the leaves and buds of Castanea mollissima and Ginkgo biloba was tested. The method is based on the silica-based purification protocol developed by Boom et al. (1990). By modifying the protocol, plant genome DNA could be extracted easily from dormant buds, mature leaves, and other parts of plant. Our results showed that the purified DNA was of high purity and could be analyzed by PCR. Furthermore, this CTAB-silica method took much less time for a successful DNA purification process compared to the traditional methods (CTAB and SDS). By our method, the suitable DNA can be extracted and purified from over 10 plant samples by one person in an hour.展开更多
A new alkaloid, named 6-(2',3'-dihydroxy-4'-hydroxymethyl-tetrahydro-furan-1'-yl)cyclopentadiene[c]pyrrole-1,3-diol, was isolated from the seeds of Castanea mollissima Blume. The structure was elucidated based o...A new alkaloid, named 6-(2',3'-dihydroxy-4'-hydroxymethyl-tetrahydro-furan-1'-yl)cyclopentadiene[c]pyrrole-1,3-diol, was isolated from the seeds of Castanea mollissima Blume. The structure was elucidated based on spectroscopic evidence including 2D NMR techniques.展开更多
The chestnuts genus(Castanea spp.)is comprised of economically important trees native to the Northern hemisphere that are used as food and hardwood timber.Here,a very efficient method for micropropagation of European&...The chestnuts genus(Castanea spp.)is comprised of economically important trees native to the Northern hemisphere that are used as food and hardwood timber.Here,a very efficient method for micropropagation of European×Japanese chestnut hybrids(Castanea sativa×C.crenata)is described.Woody Plant Medium was used as the basal medium.In vitro shoots of four rootstock cultivars were micropropagated without shoot-tip necrosis on multiplication medium containing 5.7 or 11.4μmol·L^(−1)zeatin riboside,and were rooted on rooting medium containing 2.46μmol·L^(−1)indolebutyric acid.Monthly shootmultiplication rates for each cultivarwere 2–5 folds.In vitro rooting percentages for four cultivars were 87%for‘Maraval’,67%for‘Marigoule’,93%for‘Marsol’,and 97%for‘Précoce Migoule’.Within a 5 week period,80%–95%of rooted shoots were successfully acclimated under high humidity conditions after they were planted in either soil or rockwool.展开更多
Cottonseed hull substrates blended with different ratios of Castanea mollissima Blume shell were prepared and used for the cultivation of Pleurotus geesteranus. The effects of the chestnut shell content on the mycelia...Cottonseed hull substrates blended with different ratios of Castanea mollissima Blume shell were prepared and used for the cultivation of Pleurotus geesteranus. The effects of the chestnut shell content on the mycelial growth rate, yield, nutritional composition and contents of heavy metals of the cultivated Pleurotus geesteranus were investigated. The results suggest that the Castanea mollissima Blume shell in substrate can increase the mycelial growth rate, yield, biological efficiency and the contents of protein, crude fiber, amino acids and essential amino acids of Pleurotus geesteranus. Further investigation suggests that the tannin and saponin in Castanea mollissima Blume shell and the C/N ratio of substrate significantly influence the mycelial growth rate. The crude fat content of Pleurotus geesteranus decreased, while the contents of heavy metals including mercury (Hg), arsenic (As), cadmium (Cd) and lead (Pb) increased with the increase of the Castanea mollissima Blume shell content in substrate. Based on these results, the content of Castanea mollissima Blume shell was optimized to be less than 30% for the cultivation of Pleurotus geesteranus.展开更多
Genetic material originating from contrasting European chestnut (Castanea sativa) populations of Greece, Italy and Spain was evaluated in a common garden test situated in Greece. The aim of the study is to device an a...Genetic material originating from contrasting European chestnut (Castanea sativa) populations of Greece, Italy and Spain was evaluated in a common garden test situated in Greece. The aim of the study is to device an appropriate selection strategy by identifying and conserving superior genotypes for current and future use in breeding programs. Breeding material consisted of 143 open-pollinated families growing in a common garden provenance-progeny experimental trial. Growth trait genetic parameters were estimated and response to selection was evaluated using family, within family and combined selection methods. Two models were employed for the estimation of family variance and genetic parameters. The CVA varied between 12.1% and 67% among traits and models, showing an increasing trend with age. Heritability estimates were high;however their variation with age was irregular. Selection of superior families regarding three years of measurement for height, diameter, volume index and number of leaves showed a potential gain of 12% - 25%, 12% - 28%, 33% - 73% and 21% - 49% over the mean of all plants. Genetic gain for volume index was the highest among the traits studied and the joint model used presented a more effective selection strategy. Results indicate that the experimental trial studied presented substantial genetic variation and sufficient genetic gain opportunities for quantitative traits of economic importance. These findings suggest that inferior trees can be rogued from the experimental trial and a seedling seed orchard of Castanea sativa in Greece can be established.展开更多
Sweet chestnut (Castanea sativa Mill.), the only native species of Castanea genus in Europe, occupies over 12,000 ha in Andalusia (South of Spain). From 2000 until now, we have carried out different activities foc...Sweet chestnut (Castanea sativa Mill.), the only native species of Castanea genus in Europe, occupies over 12,000 ha in Andalusia (South of Spain). From 2000 until now, we have carried out different activities focused on the location and cataloguing of the different chestnut groves in the region and the evaluation of the genetic variability contained in this germplasm. Two different types of chestnut groves were detected: one of clonal nature (varieties obtained by grafting) and another of open pollination (trees from seed). In the first case, the aim of our study was to identify and characterise the main chestnut traditional varieties. High levels of genetic variability were detected in clonal orchards by means of morphological and molecular analysis. A total of 38 varieties were identified: 12 in Huelva and 26 in Malaga regions. Moreover, we reported data about the presence of synonymies and homonymies. Our results indicate that chestnut production in this region is a traditional system that uses varieties developed in situ, constituting a genuine system of 'on farm' conservation. Nevertheless, their preservation is seriously threatened in most zones due to the varietal substitution, the low profit or the abandonment, which determines the urgent necessity to safeguard these genetic resources. Furthermore, preliminary results for chestnut populations indicated a high degree of genetic variation.展开更多
The xenia effect results in pollen affecting the setting rate and the appearance and quality of fruits. To further understand this phenomenon,we investigated the xenia effect in Castanea henryi using the cultivars ‘H...The xenia effect results in pollen affecting the setting rate and the appearance and quality of fruits. To further understand this phenomenon,we investigated the xenia effect in Castanea henryi using the cultivars ‘Huali 1', ‘Huali 2', ‘Huali 3', and ‘Huangzhen' as materials. Twenty combinations of self-, cross-, and natural pollination were undertaken in a chestnut orchard in Chenzhou City, Hunan Province, China. Significant differences were observed among the pollination combinations in terms of the time of fruit ripening, rate of fruit setting, size of the barbed shell and nut, and content of soluble sugars, fats, proteins, amylose, and vitamin C. No significant differences were observed with regard to nut rate,content of total starch, and moisture content. The fruit quality of the 20 pollination combinations was evaluated using a subordinate function method,and showed that Huali 2 × Huali 3 was the best combination, and Huangzhen × Huangzhen was the most ineffective combination. Therefore, we recommend the combination of Huali 2 × Huali 3 for the future production of C. henryi.展开更多
采用室外定点观察,子实体诱导及r DNA ITS、MS204、tef1-α3种分子标记进行系统发育分析等方法,对板栗褐缘叶枯病Phomopsis castaneae-mollissimae的协同致病菌板栗蛇孢日规壳Ophiognomonia castaneae的生活史进行了研究。结果表明,每年...采用室外定点观察,子实体诱导及r DNA ITS、MS204、tef1-α3种分子标记进行系统发育分析等方法,对板栗褐缘叶枯病Phomopsis castaneae-mollissimae的协同致病菌板栗蛇孢日规壳Ophiognomonia castaneae的生活史进行了研究。结果表明,每年7月下旬至8月初叶片发病初期很少分离到O.castaneae,随着病斑扩大该菌的分离频率逐渐增大,至发病后期其分离频率可高达78.5%,甚至可超过致病菌P.castaneae-mollissimae,10月下旬板栗落叶背面的病斑上开始形成O.castaneae的分生孢子盘,11月下旬开始形成O.castaneae的子囊壳原基,次年5、6月越冬落叶背面的病斑上长出子囊壳;带病斑的叶片经室内外诱导,0–25℃范围均可产生成熟子囊壳;湿度是决定子囊壳能否形成的关键因素,强光照不利于子囊壳的产生;分离物的菌丝体在PDA培养基上培养,易产生分生孢子;将分离物分为两种交配型,相互交配后6个月所有处理均未长出该菌的有性型子实体。室外定点观察及r DNA ITS、MS204、tef1-α3种分子标记表明分离物和病斑上的子囊孢子及其萌发菌丝为O.castaneae的不同生长发育阶段。展开更多
Castanea squinii Dode,an endemic tree widely distributed in China,plays an important role both in chestnut breeding and forest ecosystem function.The spatial genetic structure within and among populations is an import...Castanea squinii Dode,an endemic tree widely distributed in China,plays an important role both in chestnut breeding and forest ecosystem function.The spatial genetic structure within and among populations is an important part of the evolutionary and ecological genetic dynamics of natural populations,and can provide insights into effective conservation of genetic resources.In the present study,the spatial genetic structure of a panmictic natural population of C.sequinii in the Dabie Mountain region was investigated using microsatellite markers.Nine prescreened microsatellite loci generated 29-33 alleles each,and were used for spatial autocorrelation analysis.Based on Moran’s I coefficient,a panmictic population of C.sequinii in the Dabie Mountain region was found to be lacking a spatial genetic structure.These results suggest that a high pollen-mediated gene flow among subpopulations counteract genetic drift and/or genetic differentiation and plays an important role in maintaining a random and panmictic population structure in C.sequinii populations.Further,a spatial genetic structure was detected in each subpopulation’s scale(0.228 km),with all three subpopulations showing significant fine-scale structure.The genetic variation was found to be nonrandomly distributed within 61 m in each subpopulation(Moran’s I positive values).Although Moran’s I values varied among the different subpopulations,Moran’s I in all the three subpopulations reached the expected values with an increase in distances,suggesting a generally patchy distribution in the subpopula-tions.The fine-scale structure seems to reflect restricted seed dispersal and microenvironment selection in C.sequinii.These results have important implications for understanding the evolutionary history and ecological process of the natural population of C.sequinii and provide baseline data for formulating a conservation strategy of Castanea species.展开更多
This paper deals with the initial plus trees selected in the excellent plantations, and 60 excellent phenotypes were gained. With correlation analysis, path analysis, regression analysis and clustering analysis, the r...This paper deals with the initial plus trees selected in the excellent plantations, and 60 excellent phenotypes were gained. With correlation analysis, path analysis, regression analysis and clustering analysis, the results of studying the effect of 13 factors on unit yield show that the height, crown area and branching ability are highly signiflcant correlated with the unityield. Crown area, soil fertility, anthracnose infection rate, proportion of nutrient andfruited branches and meanfruit weight have...展开更多
基金supported by the National Natural Science Foundation of China (No. 30870333)Rapid Assessment Program of Biodiversity organized by Peking University
文摘The ant genus Myopopone Roger is distributed in Oriental and Indo-Australian regions.Only one valid species,M.castanea(Smith),is recognized in the genus up to date.M.castanea(Smith) is recorded in Tibet,China,for the first time.Complete information,including characters of the genus,detailed measurements,descriptions,and illustrations of worker and queen castes of M.castanea,is provided.
基金Supported by Key Projects in the National Science&Technology Pil-lar Program during the Eleventh Five-Year Plan Period(2006BAD01A1703-1)~~
文摘[Objective] The aim was to study the supporting raising technology of Castanea mollissima Blume molecular marker-assisted selection to reduce the cost and time for chestnut breeding.[Method] To find the best cutting method,10 treatments were designed according to transverse diameter and vertical diameter of the chestnut including different cutting ratios in 1/2,1/3,1/4 and different directions about cross cutting,vertical cutting,bevel cutting and two side-cutting.The germination rate,seedling survival rate and morphological indicators of the treatments were measured;significant difference among them was also analyzed.[Result] 1/3 bevel cutting was the best,which not only could give high germination rate and survival rate,but also could guarantee high quality of nursery stock,which did not grow so differently with the untreated seedlings.[Conclusion] This way can not only reduce too much cost and time for seedling breeding,but also promote the germination of chestnut in advance,which could do much good to production.
基金the Project of Construction of Innovative Teams and Teacher Career Development for Universities and Colleges under Beijing Municipality,China(IDHT20180509)the National Key Research&Development Program of China(2018YFD1000605)the Opening Project of Beijing Key Laboratory of New Technology in Agricultural Application,China(kf2018024)。
文摘Chinese chestnut is an important nut tree around the world.Although the types of Chinese chestnut resources are abundant,resource utilization and protection of chestnut accessions are still very limited.Here,we fingerprinted and determined the genetic relationships and core collections of Chinese chestnuts using 18 fluorescently labeled SSR markers generated from 146 chestnut accessions.Our analyses showed that these markers from the tested accessions are highly polymorphic,with an average allele number(N_(a))and polymorphic information content(PIC)of 8.100 and 0.622 per locus,respectively.Using these strongly distinguishing markers,we successfully constructed unique fingerprints for 146 chestnut accessions and selected seven of the SSR markers as core markers to rapidly distinguish different accessions.Our exploration of the genetic relationships among the five cultivar groups indicated that Chinese chestnut accessions are divided into three regional type groups:group I(North China(NC)and Northwest China(NWC)cultivar groups),group II(middle and lower reaches of the Yangtze River(MLY)cultivar group)and group III(Southeast China(SEC)and Southwest China(SWC)cultivar groups).Finally,we selected 45 core collection members which represent the most genetic diversity of Chinese chestnut accessions.This study provides valuable information for identifying chestnut accessions and understanding the phylogenetic relationships among cultivar groups,which can serve as the basis for efficient breeding in the future.
文摘A new method CTAB-silica for DNA extraction and purification from the leaves and buds of Castanea mollissima and Ginkgo biloba was tested. The method is based on the silica-based purification protocol developed by Boom et al. (1990). By modifying the protocol, plant genome DNA could be extracted easily from dormant buds, mature leaves, and other parts of plant. Our results showed that the purified DNA was of high purity and could be analyzed by PCR. Furthermore, this CTAB-silica method took much less time for a successful DNA purification process compared to the traditional methods (CTAB and SDS). By our method, the suitable DNA can be extracted and purified from over 10 plant samples by one person in an hour.
文摘A new alkaloid, named 6-(2',3'-dihydroxy-4'-hydroxymethyl-tetrahydro-furan-1'-yl)cyclopentadiene[c]pyrrole-1,3-diol, was isolated from the seeds of Castanea mollissima Blume. The structure was elucidated based on spectroscopic evidence including 2D NMR techniques.
基金the Michigan State University-Ernie and Mabel Rogers Endowment.
文摘The chestnuts genus(Castanea spp.)is comprised of economically important trees native to the Northern hemisphere that are used as food and hardwood timber.Here,a very efficient method for micropropagation of European×Japanese chestnut hybrids(Castanea sativa×C.crenata)is described.Woody Plant Medium was used as the basal medium.In vitro shoots of four rootstock cultivars were micropropagated without shoot-tip necrosis on multiplication medium containing 5.7 or 11.4μmol·L^(−1)zeatin riboside,and were rooted on rooting medium containing 2.46μmol·L^(−1)indolebutyric acid.Monthly shootmultiplication rates for each cultivarwere 2–5 folds.In vitro rooting percentages for four cultivars were 87%for‘Maraval’,67%for‘Marigoule’,93%for‘Marsol’,and 97%for‘Précoce Migoule’.Within a 5 week period,80%–95%of rooted shoots were successfully acclimated under high humidity conditions after they were planted in either soil or rockwool.
文摘Cottonseed hull substrates blended with different ratios of Castanea mollissima Blume shell were prepared and used for the cultivation of Pleurotus geesteranus. The effects of the chestnut shell content on the mycelial growth rate, yield, nutritional composition and contents of heavy metals of the cultivated Pleurotus geesteranus were investigated. The results suggest that the Castanea mollissima Blume shell in substrate can increase the mycelial growth rate, yield, biological efficiency and the contents of protein, crude fiber, amino acids and essential amino acids of Pleurotus geesteranus. Further investigation suggests that the tannin and saponin in Castanea mollissima Blume shell and the C/N ratio of substrate significantly influence the mycelial growth rate. The crude fat content of Pleurotus geesteranus decreased, while the contents of heavy metals including mercury (Hg), arsenic (As), cadmium (Cd) and lead (Pb) increased with the increase of the Castanea mollissima Blume shell content in substrate. Based on these results, the content of Castanea mollissima Blume shell was optimized to be less than 30% for the cultivation of Pleurotus geesteranus.
文摘Genetic material originating from contrasting European chestnut (Castanea sativa) populations of Greece, Italy and Spain was evaluated in a common garden test situated in Greece. The aim of the study is to device an appropriate selection strategy by identifying and conserving superior genotypes for current and future use in breeding programs. Breeding material consisted of 143 open-pollinated families growing in a common garden provenance-progeny experimental trial. Growth trait genetic parameters were estimated and response to selection was evaluated using family, within family and combined selection methods. Two models were employed for the estimation of family variance and genetic parameters. The CVA varied between 12.1% and 67% among traits and models, showing an increasing trend with age. Heritability estimates were high;however their variation with age was irregular. Selection of superior families regarding three years of measurement for height, diameter, volume index and number of leaves showed a potential gain of 12% - 25%, 12% - 28%, 33% - 73% and 21% - 49% over the mean of all plants. Genetic gain for volume index was the highest among the traits studied and the joint model used presented a more effective selection strategy. Results indicate that the experimental trial studied presented substantial genetic variation and sufficient genetic gain opportunities for quantitative traits of economic importance. These findings suggest that inferior trees can be rogued from the experimental trial and a seedling seed orchard of Castanea sativa in Greece can be established.
文摘Sweet chestnut (Castanea sativa Mill.), the only native species of Castanea genus in Europe, occupies over 12,000 ha in Andalusia (South of Spain). From 2000 until now, we have carried out different activities focused on the location and cataloguing of the different chestnut groves in the region and the evaluation of the genetic variability contained in this germplasm. Two different types of chestnut groves were detected: one of clonal nature (varieties obtained by grafting) and another of open pollination (trees from seed). In the first case, the aim of our study was to identify and characterise the main chestnut traditional varieties. High levels of genetic variability were detected in clonal orchards by means of morphological and molecular analysis. A total of 38 varieties were identified: 12 in Huelva and 26 in Malaga regions. Moreover, we reported data about the presence of synonymies and homonymies. Our results indicate that chestnut production in this region is a traditional system that uses varieties developed in situ, constituting a genuine system of 'on farm' conservation. Nevertheless, their preservation is seriously threatened in most zones due to the varietal substitution, the low profit or the abandonment, which determines the urgent necessity to safeguard these genetic resources. Furthermore, preliminary results for chestnut populations indicated a high degree of genetic variation.
基金Financial support was provided by the ‘12th Five-Year’ Science and Technology Support Program of China (2013BAD14B04)
文摘The xenia effect results in pollen affecting the setting rate and the appearance and quality of fruits. To further understand this phenomenon,we investigated the xenia effect in Castanea henryi using the cultivars ‘Huali 1', ‘Huali 2', ‘Huali 3', and ‘Huangzhen' as materials. Twenty combinations of self-, cross-, and natural pollination were undertaken in a chestnut orchard in Chenzhou City, Hunan Province, China. Significant differences were observed among the pollination combinations in terms of the time of fruit ripening, rate of fruit setting, size of the barbed shell and nut, and content of soluble sugars, fats, proteins, amylose, and vitamin C. No significant differences were observed with regard to nut rate,content of total starch, and moisture content. The fruit quality of the 20 pollination combinations was evaluated using a subordinate function method,and showed that Huali 2 × Huali 3 was the best combination, and Huangzhen × Huangzhen was the most ineffective combination. Therefore, we recommend the combination of Huali 2 × Huali 3 for the future production of C. henryi.
文摘采用室外定点观察,子实体诱导及r DNA ITS、MS204、tef1-α3种分子标记进行系统发育分析等方法,对板栗褐缘叶枯病Phomopsis castaneae-mollissimae的协同致病菌板栗蛇孢日规壳Ophiognomonia castaneae的生活史进行了研究。结果表明,每年7月下旬至8月初叶片发病初期很少分离到O.castaneae,随着病斑扩大该菌的分离频率逐渐增大,至发病后期其分离频率可高达78.5%,甚至可超过致病菌P.castaneae-mollissimae,10月下旬板栗落叶背面的病斑上开始形成O.castaneae的分生孢子盘,11月下旬开始形成O.castaneae的子囊壳原基,次年5、6月越冬落叶背面的病斑上长出子囊壳;带病斑的叶片经室内外诱导,0–25℃范围均可产生成熟子囊壳;湿度是决定子囊壳能否形成的关键因素,强光照不利于子囊壳的产生;分离物的菌丝体在PDA培养基上培养,易产生分生孢子;将分离物分为两种交配型,相互交配后6个月所有处理均未长出该菌的有性型子实体。室外定点观察及r DNA ITS、MS204、tef1-α3种分子标记表明分离物和病斑上的子囊孢子及其萌发菌丝为O.castaneae的不同生长发育阶段。
基金This work was supported by KIP Pilot of Chinese Academy of Sciences(No.KSXC2-SW-104)the National Natural Science Foundation of China(Grant No.30470185).
文摘Castanea squinii Dode,an endemic tree widely distributed in China,plays an important role both in chestnut breeding and forest ecosystem function.The spatial genetic structure within and among populations is an important part of the evolutionary and ecological genetic dynamics of natural populations,and can provide insights into effective conservation of genetic resources.In the present study,the spatial genetic structure of a panmictic natural population of C.sequinii in the Dabie Mountain region was investigated using microsatellite markers.Nine prescreened microsatellite loci generated 29-33 alleles each,and were used for spatial autocorrelation analysis.Based on Moran’s I coefficient,a panmictic population of C.sequinii in the Dabie Mountain region was found to be lacking a spatial genetic structure.These results suggest that a high pollen-mediated gene flow among subpopulations counteract genetic drift and/or genetic differentiation and plays an important role in maintaining a random and panmictic population structure in C.sequinii populations.Further,a spatial genetic structure was detected in each subpopulation’s scale(0.228 km),with all three subpopulations showing significant fine-scale structure.The genetic variation was found to be nonrandomly distributed within 61 m in each subpopulation(Moran’s I positive values).Although Moran’s I values varied among the different subpopulations,Moran’s I in all the three subpopulations reached the expected values with an increase in distances,suggesting a generally patchy distribution in the subpopula-tions.The fine-scale structure seems to reflect restricted seed dispersal and microenvironment selection in C.sequinii.These results have important implications for understanding the evolutionary history and ecological process of the natural population of C.sequinii and provide baseline data for formulating a conservation strategy of Castanea species.
文摘This paper deals with the initial plus trees selected in the excellent plantations, and 60 excellent phenotypes were gained. With correlation analysis, path analysis, regression analysis and clustering analysis, the results of studying the effect of 13 factors on unit yield show that the height, crown area and branching ability are highly signiflcant correlated with the unityield. Crown area, soil fertility, anthracnose infection rate, proportion of nutrient andfruited branches and meanfruit weight have...