Thinopyrum elongatum （2n = 2x = 14, EE）, a wild relative of wheat, has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight （FHB）. In this study...Thinopyrum elongatum （2n = 2x = 14, EE）, a wild relative of wheat, has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight （FHB）. In this study, a series of wheat （cv. Chinese Spring, CS） substitution and ditelosomic lines, including Th. elongatum additions, were assessed for Type II resistance to FHB. Results indicated that the lines containing chromosome 7E of Th. elongatum gave a high level of resistance to FHB, wherein the infection did not spread beyond the inoculated floret. Furthermore, it was determined that the novel resistance gene（s） of 7E was located on the short-ann （7ES） based on sharp difference in FHB resistance between the two 7E ditelosomic lines for each arm. On the other hand, Th. elongatum chromosomes 5E and 6E likely contain gene（s） for susceptibility to FHB because the disease spreads rapidly within the inoculated spikes of these lines. Genomic in situ hybridization （GISH） analysis revealed that the alien chromosomes in the addition and substitution lines were intact, and the lines did not contain discernible genomic aberrations. GISH and multicolor-GISH analyses were further performed on three trans- location lines that also showed high levels of resistance to FHB. Lines TA3499 and TA3695 were shown to contain one pair of wheat-Th. elongatum translocated chromosomes involving fragments of 7D plus a segment of the 7E, while line TA3493 was found to contain one pair of wheat-Th, elongatum translocated chromosomes involving the D- and A-genome chromosomes of wheat. Thus, this study has established that the short-arm of chromosome 7E of Th. elongatum harbors gene（s） highly resistant to the spreading of FHB, and chromatin of 7E introgressed into wheat chromosomes largely retained the resistance, implicating the feasibility of using these lines as novel material for breeding FHB-resistant wheat cultivars.展开更多
Bemisia tabaci(Gennadius) biotype B,called a "superbug",is one of the most harmful biotypes of this species complex worldwide.In this report,the invasive mechanism and management of B.tabaci biotype B,based ...Bemisia tabaci(Gennadius) biotype B,called a "superbug",is one of the most harmful biotypes of this species complex worldwide.In this report,the invasive mechanism and management of B.tabaci biotype B,based on our 5-year studies,are presented.Six B.tabaci biotypes,B,Q,ZHJ1,ZHJ2,ZHJ3 and FJ1,have been identified in China.Biotype B dominates the other biotypes in many regions of the country.Genetic diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal application.The activities of CarE(carboxylesterase) and GSTs(glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants,which might have increased its resistance to insecticides.The higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host plants.Higher adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein genes.The indigenous B.tabaci biotypes were displaced by the biotype B within 225 d.The asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other biotypes.B.tabaci biotype B displaced Trialeurodes vaporariorum(Westwood) after 4-7 generations under glasshouse conditions.Greater adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of T.vaporariorum.Greater ability of the biotype B to switch to different host plants may enrich its host plants,which might enable it to better compete with T.vaporariorum.Native predatory natural enemies possess greater ability to suppress B.tabaci under field conditions.The kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its parasitoids.The present results provide useful information in explaining the mechanisms of genetic diversity,evolution and molecular eco-adaptation of biotype展开更多
Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in China almost 30 years ago and has become an urgent topic due to its invasiveness i...Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in China almost 30 years ago and has become an urgent topic due to its invasiveness in the coastal zone of China. The impacts of this alien species S. alterniflora on intertidal ecosystem processes in the Jiangsu coastland were investigated by comparing the sediment nutrient availability and trace element concentration characteristics in a mud flat and those of a four-year old Spartina salt marsh that had earlier been a mudflat. At each study site, fifteen plots were sampled in different seasons to determine the sediment characteristics along the tidal flats. The results suggested that Spartina salt marsh sediments had significantly higher total N, available P, and water content, but lower pH and bulk density than mudflat sediments. Sediment salinity, water content, total N, organic C, and available P decreased along a seaward gradient in the Spartina salt marsh and increased with vegetation biomass. Furthermore, the concentrations of trace elements and some metal elements in the sediment were higher under Spartina although these increases were not significant. Also, in the Spartina marsh, some heavy metals were concentrated in the surface layer of the sediment. The Spartina salt marsh in this study was only four years old; therefore, it is suggested that further study of this allen species on a longer time frame in the Jiangsu coastland should be carried out.展开更多
Barley yellow dwarf virus （BYDV） may cause a serious disease affecting wheat worldwide. True resistance to BYDV is not naturally found in wheat. BYDV resistance genes are found in more than 10 wild relative species ...Barley yellow dwarf virus （BYDV） may cause a serious disease affecting wheat worldwide. True resistance to BYDV is not naturally found in wheat. BYDV resistance genes are found in more than 10 wild relative species belonging to the genera of Thinopyrum, Agropyron, Elymus, Leymus, Roegneria, and Psathyrostachy. Through wide crosses combining with cell culture, use ofph mutants, or irradiation, 3 BYDV resistance genes in Th. intermedium, including Bdv2, Bdv3 and Bdv4, were introgressed into common wheat background. Various wheat-Th, intermedium addition and substitution, translocation lines with BYDV-resistance were developed and characterized, such as 7D-TAi#1 （bearing Bdv2）, 7B-7Ai#1, 7D-7E （beating Bdv3）, and 2D-2Ai-2 （bearing Bdv4） translocations. Three wheat varieties with BYDV resistance from Th. intermedium were developed and released in Australia and China, respectively. In addition, wheat-Agropyron cristatum translocation lines, wheat-Ag, pulcherrimum addition and substitution lines, and a wheat-Leymus multicaulis addition line （line24） with different resistance genes were developed. Cytological analysis, morphological markers, biochemical markers, and molecular markers associated with the alien chromatin carrying BYDV resistance genes were identified and applied to determine the presence of alien, chromosomes or segments, size of alien chromosome segments, and compositions of the alien chromosomes. Furthermore, some resistance-related genes, such as RGA, P450, HSP70, protein kinases, centrin, and transducin, were identified, which expressed specifically in the resistance translocation lines with Bdv2. These studies lay the foundations for developing resistant wheat cultivars and unraveling the resistance mechanism against BYDV.展开更多
Bio-invasion has caused serious ecosystem damage and enormous economic losses in China,and it has been the greatest factor to island bio-diversity reduction.Xiamen,as an important seaport with a relatively high conser...Bio-invasion has caused serious ecosystem damage and enormous economic losses in China,and it has been the greatest factor to island bio-diversity reduction.Xiamen,as an important seaport with a relatively high conservation value,is particularly vulnerable to bio-invasion for its typical island ecosystem as well as frequent human-made disturbance.As a result of field surveys,literature review, and consultation with experts,a list of 67 alien plants identified as major invaders(12 species)and emerging invade...展开更多
Plant somatic hybridization has progressed steadily over the past 35 years. Many hybrid plants have been generated from fusion combinations of different phylogenetic species, some of which have been utilized in crop b...Plant somatic hybridization has progressed steadily over the past 35 years. Many hybrid plants have been generated from fusion combinations of different phylogenetic species, some of which have been utilized in crop breeding programs. Among them, asymmetric hybrid, which usually contains a fraction of alien genome, has received more attention because of its importance in crop improvement. However, few studies have dealt with the heredity of the genome of somatic hybrid for a long time, which has limited the progress of this approach. Over recent ten years, along with the development of an effective cytogenetical tool ＂in situ hybridization （ISH）＂, asymmetric fusion of common wheat （Triticum aestivum L.） with different grasses or cereals has been greatly developed. Genetics, genomes, functional genes and agricultt, ral traits of wheat asymmetric hybrids have been subject to systematic investigations using gene cloning, genomic in situ hybridization （GISH） and molecular makers. The future goal is to fully elucidate the functional relationships among improved agronomic traits, the genes and underlying molecular mechanisms, and the genome dynamics of somatic introgression lines. This will accelerate the development of elite germplasms via somatic hybridization and the application of these materials in the molecular improvement of crop plants.展开更多
The progress of research on transferring elite genes from non-AA genome wild rice into Oryza sativa through interspecific hybridization are in three respects, that is, breeding monosomic alien addition lines （MAALs）...The progress of research on transferring elite genes from non-AA genome wild rice into Oryza sativa through interspecific hybridization are in three respects, that is, breeding monosomic alien addition lines （MAALs）, constructing introgression lines （ILs） and analyzing the heredity of the characters and mapping the related genes. There are serious reproductive barriers, mainly incrossability and hybrid sterility, in the interspecific hybridization of O. sativa with non-AA genome wild rice. These are the ＇bottleneck＇ for transferring elite genes from wild rice to O. sativa. Combining traditional crossing method with biotechnique is a reliable way to overcome the reproductive barriers and to improve the utilizing efficiency of non-AA genome wild rice.展开更多
Mikania micrantha Kunth is an invasive alien weed and known as a plant killer around the world.Accurately and rapidly identifying M.micrantha in the wild is important for monitoring its growth status,as this helps man...Mikania micrantha Kunth is an invasive alien weed and known as a plant killer around the world.Accurately and rapidly identifying M.micrantha in the wild is important for monitoring its growth status,as this helps management officials to take the necessary steps to devise a comprehensive strategy to control the invasive weed in the identified area.However,this approach still mainly depends on satellite remote sensing and manual inspection.The cost is high and the accuracy rate and efficiency are low.We acquired color images of the monitoring area in the wild environment using an Unmanned Aerial Vehicle(UAV)and proposed a novel network-MmNet-based on a deep Convolutional Neural Network(CNN)to identify M.micrantha in the images.The network consists of AlexNet Local Response Normalization(LRN),along with the GoogLeNet and continuous convolution of VGG inception models.After training and testing,the identification of 400 testing samples by MmNet is very good,with accuracy of 94.50%and time cost of 10.369 s.Moreover,in quantitative comparative analysis,the proposed MmNet not only has high accuracy and efficiency but also simple construction and outstanding repeatability.Compared with recently popular CNNs,MmNet is more suitable for the identification of M.micrantha in the wild.However,to meet the challenge of wild environments,more M.micrantha images need to be acquired for MmNet training.In addition,the classification labels need to be sorted in more detail.Altogether,this research provides some theoretical and scientific basis for the development of intelligent monitoring and early warning systems for M.micrantha and other invasive species.展开更多
Leymus mollis （Trin.） Pilger （NsNsXmXm, 2n = 28）, a wild relative of common wheat, possesses many potentially valuable traits that could be transferred to common wheat during breeding programs. In this study, the ...Leymus mollis （Trin.） Pilger （NsNsXmXm, 2n = 28）, a wild relative of common wheat, possesses many potentially valuable traits that could be transferred to common wheat during breeding programs. In this study, the karyotypic constitution of a wheat - L. mollis 3D（3Ns#1） disomic substitution line isolated from the F5 progeny of octoploid Tritileymus M842-16 x Triticum durum cv. D4286, which was designated as 10DM57, was determined using genomic in situ hybridization （GISH）, fluorescent in situ hybridization （FISH）, SSR markers, and EST- STS markers. Screening of mitosis and meiosis showed that 10DM57 had a chromosome karyotype of 2n = 42 =21Ⅱ. GISH indicated that 10DM57 was a line with 40 chromosomes from wheat and two of the Ns chromosomes from L. mollis, which formed a ring bivalent in pollen mother cells at metaphase I. FISH analysis showed that the chromosome 3D may be replaced by 3Ns#1 in 10DM57. DNA markers, including SSR and EST-STS primers, showed that the pair of wheat chromosome 3D in 10DM57 was substituted by the pair of chromosome 3Ns#t from L. mollis. Evaluation of the agronomic traits showed that, compared with its common wheat relative 7182, 10DM57 was resistant to leaf rust while the spike length and number of spikes per plant were improved significantly, which correlated with a higher wheat yield. The new germplasm, 10DM57, could be exploited as an intermediate material in wheat genetic and breeding programs.展开更多
Interspecific alien addition lines have played significant roles in gene mapping, intergenomic gene transfer and chromosomal homoeological identification between closely related species. Selection of alien addition li...Interspecific alien addition lines have played significant roles in gene mapping, intergenomic gene transfer and chromosomal homoeological identification between closely related species. Selection of alien addition lines was conducted by karyotype analysis and morphological observation with the reference of parents. Triploid interspecies hybrid （AAC, 2n = 3x = 29） was obtained from Brassica campestris ssp. chinensis var. parachinensis Qinglu 9601 （tetraploid, AAAA, 2n = 4x = 40） x B. oleracea var. alboglabra Baihua 9705 （diploid, CC, 2n = 2x = 18） by immature hybrid embryo culture in vitro. Five different alien monosomic addition lines （AA ＋ C2, AA ＋ C3, AA ＋ C4, AA ＋ C6, AA ＋ C7） were obtained from the backcross progenies of AAC x AA. Each alien monosomic addition line has some specific morphological characters. It is feasible to obtain alien addition lines from the progenies of AAC × AA by karyotype analysis and morphological observation based on the reference of parents展开更多
Rhus typhina, an alien species introduced from North America, was identified as a main afforestation species in Beijing municipality. However, its invasiveness is still at odds. To clarify this problem, we applied the...Rhus typhina, an alien species introduced from North America, was identified as a main afforestation species in Beijing municipality. However, its invasiveness is still at odds. To clarify this problem, we applied the North American Screening System and the Australian Screening System to preliminarily predict its invasion possibility. Both screening systems gave the same recommendation to ＂reject＂. The geographical distribution was surveyed, with the population features of R. typhina against the native plant communities being assessed. With anthropogenic assistance, R. typhina has been scattered on almost all habitats from downtown to mountains, including roadsides, farmlands and protected areas. As a clonal shrub, R. typhina possessed a high spreading rate, varying from 6.3 m/3 years at sterile habitats to 6.7 m/3 years at fertile ones. Significantly lower species richness, individual density and diversity were observed in the R. typhina community than those of the native Vitex negundo Linn.var. heterophylla （Franch.） Rehd. community at both sterile and fertile habitats. Continual wide plantation of R. typhina may further foster its population expansion, which helps the species to overcome spatial isolation, The fact that each root fragment can develop into a new individual makes R. typhina very difficult to be eradicated once established. From a biological point of view, we believe that R. typhina is a plant invader in Beijing. We therefore suggest the government should remove the name of R. typhina from the main tree species list in afforesUng Beijing.展开更多
A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper res...A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper resistance and yield traits. A linkage map consisting of 119 DNA markers and spanned for 1188 cM over the 12 rice chromosomes was constructed. Thirty-two chromosomal segment substitution lines were selected based on the percentage of Xieqingzao B allele at marker loci. These lines are of great potential for gene mapping and alien gene introgression.展开更多
Although alien and invasive plant species have been researched extensively in the European part of Russia,the situation in Siberia is another matter.Hitherto,alien and invasive species in Siberia have not received muc...Although alien and invasive plant species have been researched extensively in the European part of Russia,the situation in Siberia is another matter.Hitherto,alien and invasive species in Siberia have not received much attention because this problem was not especially acute in Siberia.The lack of attention on alien and invasive species in Siberia is attributed to three major reasons：1） Low vegetative productivity and sparse human populations in the Siberian territory have limited botanical research interest in the area.2） Severe Siberian climate likely prevents many alien and invasive species from increasing their distribution into Siberia.3） Most Siberian plant communities have not been human-transformed and thus may be resistant to newcomers.Nevertheless,recent increased economic activities have resulted in increasing plant migration to Siberia,and this process should be monitored.Furthermore,global environmental changes may also have made Siberia more favorable for more alien and invasive species.Currently,research on alien and invasive species has begun in the Altai-Sayan region（Western Siberia） and the Magadan region （Northeastern Asia）.展开更多
In order to transfer useful genes of Hordeum californicum into common wheat （Triticum aestivum L.）, the T. aestivum c.v. Chinese Spring （CS）-H. californicum amphiploid was crossed to CS, and its backcrossing and s...In order to transfer useful genes of Hordeum californicum into common wheat （Triticum aestivum L.）, the T. aestivum c.v. Chinese Spring （CS）-H. californicum amphiploid was crossed to CS, and its backcrossing and self-fertilized progenies were analyzed by morpho- logical observation, cytological, biochemical and molecular marker techniques. Alien addition lines with two H. californicum chromo- somes were identified and their genetic constitution was characterized. STS-PCR analysis using chromosome 2B specific markers indi- cated that chromosome H3 of H. californicum belongs to homoeologous group 2, and was thus designated 2H. SDS-PAGE showed that chromosome H2 of H. californicum belongs to homoeologous group 5, and was designated 5H. The CS-H. californicum amphiploid and the chromosome addition lines （DA2H and MA5H） identified were evaluated for powdery mildew （Erysiphe graminis f. sp. triticii） resis- tance in field. The preliminary results indicated that the amphiploid showed higher powdery mildew resistance than CS. However, chro- mosome addition lines DA2H and MA5H were highly susceptible to powdery mildew, indicating that major powdery mildew resistant genes of H. californicum should be located on chromosomes other than 2H and 5H.展开更多
基金supported by the grant of the National High Technology Research and Development Program("863"Program)of China(No.2011AA100101)
文摘Thinopyrum elongatum （2n = 2x = 14, EE）, a wild relative of wheat, has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight （FHB）. In this study, a series of wheat （cv. Chinese Spring, CS） substitution and ditelosomic lines, including Th. elongatum additions, were assessed for Type II resistance to FHB. Results indicated that the lines containing chromosome 7E of Th. elongatum gave a high level of resistance to FHB, wherein the infection did not spread beyond the inoculated floret. Furthermore, it was determined that the novel resistance gene（s） of 7E was located on the short-ann （7ES） based on sharp difference in FHB resistance between the two 7E ditelosomic lines for each arm. On the other hand, Th. elongatum chromosomes 5E and 6E likely contain gene（s） for susceptibility to FHB because the disease spreads rapidly within the inoculated spikes of these lines. Genomic in situ hybridization （GISH） analysis revealed that the alien chromosomes in the addition and substitution lines were intact, and the lines did not contain discernible genomic aberrations. GISH and multicolor-GISH analyses were further performed on three trans- location lines that also showed high levels of resistance to FHB. Lines TA3499 and TA3695 were shown to contain one pair of wheat-Th. elongatum translocated chromosomes involving fragments of 7D plus a segment of the 7E, while line TA3493 was found to contain one pair of wheat-Th, elongatum translocated chromosomes involving the D- and A-genome chromosomes of wheat. Thus, this study has established that the short-arm of chromosome 7E of Th. elongatum harbors gene（s） highly resistant to the spreading of FHB, and chromatin of 7E introgressed into wheat chromosomes largely retained the resistance, implicating the feasibility of using these lines as novel material for breeding FHB-resistant wheat cultivars.
基金Supported by the National Basic Research and Development Program of China (973 Program) of China (Grant No.2009CB119200)
文摘Bemisia tabaci(Gennadius) biotype B,called a "superbug",is one of the most harmful biotypes of this species complex worldwide.In this report,the invasive mechanism and management of B.tabaci biotype B,based on our 5-year studies,are presented.Six B.tabaci biotypes,B,Q,ZHJ1,ZHJ2,ZHJ3 and FJ1,have been identified in China.Biotype B dominates the other biotypes in many regions of the country.Genetic diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal application.The activities of CarE(carboxylesterase) and GSTs(glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants,which might have increased its resistance to insecticides.The higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host plants.Higher adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein genes.The indigenous B.tabaci biotypes were displaced by the biotype B within 225 d.The asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other biotypes.B.tabaci biotype B displaced Trialeurodes vaporariorum(Westwood) after 4-7 generations under glasshouse conditions.Greater adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of T.vaporariorum.Greater ability of the biotype B to switch to different host plants may enrich its host plants,which might enable it to better compete with T.vaporariorum.Native predatory natural enemies possess greater ability to suppress B.tabaci under field conditions.The kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its parasitoids.The present results provide useful information in explaining the mechanisms of genetic diversity,evolution and molecular eco-adaptation of biotype
基金Project supported by the Natural Science Foundation of Jiangsu Province (No.JSNSF 20050307)the National Natural Science Foundation of China (No.NSFC 30470326).
文摘Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in China almost 30 years ago and has become an urgent topic due to its invasiveness in the coastal zone of China. The impacts of this alien species S. alterniflora on intertidal ecosystem processes in the Jiangsu coastland were investigated by comparing the sediment nutrient availability and trace element concentration characteristics in a mud flat and those of a four-year old Spartina salt marsh that had earlier been a mudflat. At each study site, fifteen plots were sampled in different seasons to determine the sediment characteristics along the tidal flats. The results suggested that Spartina salt marsh sediments had significantly higher total N, available P, and water content, but lower pH and bulk density than mudflat sediments. Sediment salinity, water content, total N, organic C, and available P decreased along a seaward gradient in the Spartina salt marsh and increased with vegetation biomass. Furthermore, the concentrations of trace elements and some metal elements in the sediment were higher under Spartina although these increases were not significant. Also, in the Spartina marsh, some heavy metals were concentrated in the surface layer of the sediment. The Spartina salt marsh in this study was only four years old; therefore, it is suggested that further study of this allen species on a longer time frame in the Jiangsu coastland should be carried out.
基金supported by the National "Hi-Tech" Programs "Functional Genomics of Wheat Disease Resis-tance" (No. 2006AA10A104)"Biotech. Breeding of Wheat Varieties with Multi-Resistance and Good Quality" (No. 2006AA100102)
文摘Barley yellow dwarf virus （BYDV） may cause a serious disease affecting wheat worldwide. True resistance to BYDV is not naturally found in wheat. BYDV resistance genes are found in more than 10 wild relative species belonging to the genera of Thinopyrum, Agropyron, Elymus, Leymus, Roegneria, and Psathyrostachy. Through wide crosses combining with cell culture, use ofph mutants, or irradiation, 3 BYDV resistance genes in Th. intermedium, including Bdv2, Bdv3 and Bdv4, were introgressed into common wheat background. Various wheat-Th, intermedium addition and substitution, translocation lines with BYDV-resistance were developed and characterized, such as 7D-TAi#1 （bearing Bdv2）, 7B-7Ai#1, 7D-7E （beating Bdv3）, and 2D-2Ai-2 （bearing Bdv4） translocations. Three wheat varieties with BYDV resistance from Th. intermedium were developed and released in Australia and China, respectively. In addition, wheat-Agropyron cristatum translocation lines, wheat-Ag, pulcherrimum addition and substitution lines, and a wheat-Leymus multicaulis addition line （line24） with different resistance genes were developed. Cytological analysis, morphological markers, biochemical markers, and molecular markers associated with the alien chromatin carrying BYDV resistance genes were identified and applied to determine the presence of alien, chromosomes or segments, size of alien chromosome segments, and compositions of the alien chromosomes. Furthermore, some resistance-related genes, such as RGA, P450, HSP70, protein kinases, centrin, and transducin, were identified, which expressed specifically in the resistance translocation lines with Bdv2. These studies lay the foundations for developing resistant wheat cultivars and unraveling the resistance mechanism against BYDV.
文摘Bio-invasion has caused serious ecosystem damage and enormous economic losses in China,and it has been the greatest factor to island bio-diversity reduction.Xiamen,as an important seaport with a relatively high conservation value,is particularly vulnerable to bio-invasion for its typical island ecosystem as well as frequent human-made disturbance.As a result of field surveys,literature review, and consultation with experts,a list of 67 alien plants identified as major invaders(12 species)and emerging invade...
基金supported by the National Basic Research 973 Program of China (No. 2009CB118300 and 2006CB100100)the Major Program of the Natural Science Foundation of China (No. 30530480)+2 种基金the Major Science Foundation of Shandong Province (No. Q2006D02)the National Natural Science Foundation of China (No. 30871320 and 30370857)the National 863 High Tech-nology Research and Development Project (No. 2006AA100102)
文摘Plant somatic hybridization has progressed steadily over the past 35 years. Many hybrid plants have been generated from fusion combinations of different phylogenetic species, some of which have been utilized in crop breeding programs. Among them, asymmetric hybrid, which usually contains a fraction of alien genome, has received more attention because of its importance in crop improvement. However, few studies have dealt with the heredity of the genome of somatic hybrid for a long time, which has limited the progress of this approach. Over recent ten years, along with the development of an effective cytogenetical tool ＂in situ hybridization （ISH）＂, asymmetric fusion of common wheat （Triticum aestivum L.） with different grasses or cereals has been greatly developed. Genetics, genomes, functional genes and agricultt, ral traits of wheat asymmetric hybrids have been subject to systematic investigations using gene cloning, genomic in situ hybridization （GISH） and molecular makers. The future goal is to fully elucidate the functional relationships among improved agronomic traits, the genes and underlying molecular mechanisms, and the genome dynamics of somatic introgression lines. This will accelerate the development of elite germplasms via somatic hybridization and the application of these materials in the molecular improvement of crop plants.
文摘The progress of research on transferring elite genes from non-AA genome wild rice into Oryza sativa through interspecific hybridization are in three respects, that is, breeding monosomic alien addition lines （MAALs）, constructing introgression lines （ILs） and analyzing the heredity of the characters and mapping the related genes. There are serious reproductive barriers, mainly incrossability and hybrid sterility, in the interspecific hybridization of O. sativa with non-AA genome wild rice. These are the ＇bottleneck＇ for transferring elite genes from wild rice to O. sativa. Combining traditional crossing method with biotechnique is a reliable way to overcome the reproductive barriers and to improve the utilizing efficiency of non-AA genome wild rice.
基金supported by the National Natural Science Foundation of China(3180111238)the Fund Project of the Key Laboratory of Integrated Pest Management on Crops in South China,Ministry of Agriculture and Rural Affairs,China(SCIPM2018-05)+2 种基金the Key Research and Development Program of Nanning,China(20192065)the Guangdong Science and Technology Planning Project,China(2017A020216022)the Industrial Development Fund Support Project of Dapeng District,Shenzhen,China(KY20180117)。
文摘Mikania micrantha Kunth is an invasive alien weed and known as a plant killer around the world.Accurately and rapidly identifying M.micrantha in the wild is important for monitoring its growth status,as this helps management officials to take the necessary steps to devise a comprehensive strategy to control the invasive weed in the identified area.However,this approach still mainly depends on satellite remote sensing and manual inspection.The cost is high and the accuracy rate and efficiency are low.We acquired color images of the monitoring area in the wild environment using an Unmanned Aerial Vehicle(UAV)and proposed a novel network-MmNet-based on a deep Convolutional Neural Network(CNN)to identify M.micrantha in the images.The network consists of AlexNet Local Response Normalization(LRN),along with the GoogLeNet and continuous convolution of VGG inception models.After training and testing,the identification of 400 testing samples by MmNet is very good,with accuracy of 94.50%and time cost of 10.369 s.Moreover,in quantitative comparative analysis,the proposed MmNet not only has high accuracy and efficiency but also simple construction and outstanding repeatability.Compared with recently popular CNNs,MmNet is more suitable for the identification of M.micrantha in the wild.However,to meet the challenge of wild environments,more M.micrantha images need to be acquired for MmNet training.In addition,the classification labels need to be sorted in more detail.Altogether,this research provides some theoretical and scientific basis for the development of intelligent monitoring and early warning systems for M.micrantha and other invasive species.
基金supported by the National High Technology Research and Development Program of China (863 Program) (Grant No.2011AA100501)the Major Innovation Project for Science and Technology of Shaanxi Province (Grant No.2011KTZB02-01)+1 种基金the Basic Scientific Research Project in Central Universities (Grant No.QN2011001)the Tang Zhong-Ying Breeding Funding Project at the Northwest A&F University in China
文摘Leymus mollis （Trin.） Pilger （NsNsXmXm, 2n = 28）, a wild relative of common wheat, possesses many potentially valuable traits that could be transferred to common wheat during breeding programs. In this study, the karyotypic constitution of a wheat - L. mollis 3D（3Ns#1） disomic substitution line isolated from the F5 progeny of octoploid Tritileymus M842-16 x Triticum durum cv. D4286, which was designated as 10DM57, was determined using genomic in situ hybridization （GISH）, fluorescent in situ hybridization （FISH）, SSR markers, and EST- STS markers. Screening of mitosis and meiosis showed that 10DM57 had a chromosome karyotype of 2n = 42 =21Ⅱ. GISH indicated that 10DM57 was a line with 40 chromosomes from wheat and two of the Ns chromosomes from L. mollis, which formed a ring bivalent in pollen mother cells at metaphase I. FISH analysis showed that the chromosome 3D may be replaced by 3Ns#1 in 10DM57. DNA markers, including SSR and EST-STS primers, showed that the pair of wheat chromosome 3D in 10DM57 was substituted by the pair of chromosome 3Ns#t from L. mollis. Evaluation of the agronomic traits showed that, compared with its common wheat relative 7182, 10DM57 was resistant to leaf rust while the spike length and number of spikes per plant were improved significantly, which correlated with a higher wheat yield. The new germplasm, 10DM57, could be exploited as an intermediate material in wheat genetic and breeding programs.
基金funded by the Natural Science Foundation of Hebei Province,China(C2006000450).
文摘Interspecific alien addition lines have played significant roles in gene mapping, intergenomic gene transfer and chromosomal homoeological identification between closely related species. Selection of alien addition lines was conducted by karyotype analysis and morphological observation with the reference of parents. Triploid interspecies hybrid （AAC, 2n = 3x = 29） was obtained from Brassica campestris ssp. chinensis var. parachinensis Qinglu 9601 （tetraploid, AAAA, 2n = 4x = 40） x B. oleracea var. alboglabra Baihua 9705 （diploid, CC, 2n = 2x = 18） by immature hybrid embryo culture in vitro. Five different alien monosomic addition lines （AA ＋ C2, AA ＋ C3, AA ＋ C4, AA ＋ C6, AA ＋ C7） were obtained from the backcross progenies of AAC x AA. Each alien monosomic addition line has some specific morphological characters. It is feasible to obtain alien addition lines from the progenies of AAC × AA by karyotype analysis and morphological observation based on the reference of parents
基金the Innovative Group Grant of the National Natural ScienceFoundation of China (30521002)Beijing Science and Technology Committee (H030630050490).
文摘Rhus typhina, an alien species introduced from North America, was identified as a main afforestation species in Beijing municipality. However, its invasiveness is still at odds. To clarify this problem, we applied the North American Screening System and the Australian Screening System to preliminarily predict its invasion possibility. Both screening systems gave the same recommendation to ＂reject＂. The geographical distribution was surveyed, with the population features of R. typhina against the native plant communities being assessed. With anthropogenic assistance, R. typhina has been scattered on almost all habitats from downtown to mountains, including roadsides, farmlands and protected areas. As a clonal shrub, R. typhina possessed a high spreading rate, varying from 6.3 m/3 years at sterile habitats to 6.7 m/3 years at fertile ones. Significantly lower species richness, individual density and diversity were observed in the R. typhina community than those of the native Vitex negundo Linn.var. heterophylla （Franch.） Rehd. community at both sterile and fertile habitats. Continual wide plantation of R. typhina may further foster its population expansion, which helps the species to overcome spatial isolation, The fact that each root fragment can develop into a new individual makes R. typhina very difficult to be eradicated once established. From a biological point of view, we believe that R. typhina is a plant invader in Beijing. We therefore suggest the government should remove the name of R. typhina from the main tree species list in afforesUng Beijing.
文摘A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper resistance and yield traits. A linkage map consisting of 119 DNA markers and spanned for 1188 cM over the 12 rice chromosomes was constructed. Thirty-two chromosomal segment substitution lines were selected based on the percentage of Xieqingzao B allele at marker loci. These lines are of great potential for gene mapping and alien gene introgression.
基金funded by the International Science & Technology Cooperation Program of China(2010DFA92720-06)the Visiting Professorship for Senior International Scientists,Chinese Academy of Sciences(2012T1Z0023)+2 种基金the USDA National Institute of Food and Agriculture(2010-51160-21061)supported by the Chinese Academy of Sciencesin part by the Nevada Agricultural Experiment Station
文摘Although alien and invasive plant species have been researched extensively in the European part of Russia,the situation in Siberia is another matter.Hitherto,alien and invasive species in Siberia have not received much attention because this problem was not especially acute in Siberia.The lack of attention on alien and invasive species in Siberia is attributed to three major reasons：1） Low vegetative productivity and sparse human populations in the Siberian territory have limited botanical research interest in the area.2） Severe Siberian climate likely prevents many alien and invasive species from increasing their distribution into Siberia.3） Most Siberian plant communities have not been human-transformed and thus may be resistant to newcomers.Nevertheless,recent increased economic activities have resulted in increasing plant migration to Siberia,and this process should be monitored.Furthermore,global environmental changes may also have made Siberia more favorable for more alien and invasive species.Currently,research on alien and invasive species has begun in the Altai-Sayan region（Western Siberia） and the Magadan region （Northeastern Asia）.
文摘In order to transfer useful genes of Hordeum californicum into common wheat （Triticum aestivum L.）, the T. aestivum c.v. Chinese Spring （CS）-H. californicum amphiploid was crossed to CS, and its backcrossing and self-fertilized progenies were analyzed by morpho- logical observation, cytological, biochemical and molecular marker techniques. Alien addition lines with two H. californicum chromo- somes were identified and their genetic constitution was characterized. STS-PCR analysis using chromosome 2B specific markers indi- cated that chromosome H3 of H. californicum belongs to homoeologous group 2, and was thus designated 2H. SDS-PAGE showed that chromosome H2 of H. californicum belongs to homoeologous group 5, and was designated 5H. The CS-H. californicum amphiploid and the chromosome addition lines （DA2H and MA5H） identified were evaluated for powdery mildew （Erysiphe graminis f. sp. triticii） resis- tance in field. The preliminary results indicated that the amphiploid showed higher powdery mildew resistance than CS. However, chro- mosome addition lines DA2H and MA5H were highly susceptible to powdery mildew, indicating that major powdery mildew resistant genes of H. californicum should be located on chromosomes other than 2H and 5H.
