The gene Pi-d2, conferring gene-for-gene resistance to the Chinese blast strain ZB15, was isolated from a rice variety （Digu） by the map-based cloning strategy. Here, we constructed a control plasmid pZH01-pi-d2tp3...The gene Pi-d2, conferring gene-for-gene resistance to the Chinese blast strain ZB15, was isolated from a rice variety （Digu） by the map-based cloning strategy. Here, we constructed a control plasmid pZH01-pi-d2tp309 （pZH01-tp309） and three different expression constructs, pCB-Pi-d25.3kb （pCB5.3kb）, pCB-Pi-d26.3kb （pCB6.3kb） and pZH01-Pi-d22.72kb （pZH01-2.72kb） of Pi-d2, driven by Pi-d2 gene’s own promoter or CaMV35S promoter. These constructs were separately introduced into japonica rice varieties Lijiangxintuanhegu, Taipei 309, Nipponbare and Zhonghua 9 through Agrobacterium- mediated transformation. A total of 150 transgenic rice plants were obtained from the regenerated calli selected on hygromycin. PCR, RT-PCR and Southern-blotting assay showed that the gene of interest had been integrated into rice genome and stably inherited. Thirty-five transgenic lines independently derived from T1 progeny were inoculated with the rice blast strain ZB15. Transformants exhibited resistance to rice blast at various levels. The lesions on the transgenic plant leaves were less severe than those on the controls and the resistance level of transgenic plants harboring the gene of interest from three vectors had no difference. The own promoter of Pi-d2, about 2.2 kb or 3.2 kb, had the similar promoter function as CaMV35S. Field evaluation for three successive years supported the results of artificial trial, and some lines with high resistance to rice leaf blast and neck blast were obtained.展开更多
Background The 2009 pandemic H1 N1 （pH1N1） influenza showed that relatively young adults accounted for the highest rates of hospital admission and death.In preparation for pH1N1,the aim of the study is to identify f...Background The 2009 pandemic H1 N1 （pH1N1） influenza showed that relatively young adults accounted for the highest rates of hospital admission and death.In preparation for pH1N1,the aim of the study is to identify factors associated with the mortality of patients with 2009 pH1N1 infection,especially for young patients without chronic medical conditions.Methods Retrospective observational study of 2151 severe or critical adult cases （-≥14 years old） admitted to a hospital with pH1N1 influenza from September 1,2009 to December 31,2009 from 426 hospitals of 27 Chinese provinces.A confirmed case was a person whose pH1N1 virus infection was verified by real-time reverse-transcriptase polymerase chain reaction （rRT-PCR）.Severe and critical cases were defined according to the H1N1 2009 Clinical guidelines （Third Edition,2009） released by the Ministry of Health of China.Results Among the 2151 patients,the mean age was 34.0 years.Two hundred and ninty-three （13.6%） died during hospital stay.One thousand four hundred and forty-two patients （67.0%） had no comorbidities and 189 （13.1%） of them died.Pregnancy （OR 8.03）,pneumonia （OR 8.91）,dyspnea （OR 3.95）,central nervous system （CNS） symptom （OR 1.55）,higher APACHE （Acute Physiology and Chronic Health Evaluation） Ⅱ score （OR 1.06）,Alanine aminotransferase （ALT） （OR 1.002）,and the lactate dehydrogenase （LDH） level （OR 1.001） were independent risk factors for death among adults without chronic medical conditions.Higher APACHE Ⅱ score （OR 1.08） and age （OR 1.06） were independent risk factors for death among adults with respiratory diseases.A multivariate analysis showed an association between mortality and CNS symptoms （OR 2.66）,higher APACHE Ⅱ score （OR 1.03）,ALT （OR 1.006）,and LDH level （OR 1.002） in patients with cardiovascular diseases.Dyspnea （OR 11.32） was an independent risk factor for patient death in patients with diabetes mellitus.Conclusion Clinical knowledge o展开更多
312 recombinant inbred lines （RILs） in F9 from a cross between a overwintering cold-tolerant germplasm resource Glutinous rice 89-1（Gr 89-1） and a cold-sensitive variety Shuhui 527 was used for quantitative trait ...312 recombinant inbred lines （RILs） in F9 from a cross between a overwintering cold-tolerant germplasm resource Glutinous rice 89-1（Gr 89-1） and a cold-sensitive variety Shuhui 527 was used for quantitative trait locus （QTL） analysis. The scores of percent ratooning germinability （PRG） and overwintering germinability （POG） were evaluated. The overwintering germination rate of axillary buds was scored to represent the overwintering germinability. Two significant QTLs （qPRG-4 and qPRG-7） on chromosomes 4 and 7 were detected and explained 8.3 and 7.2% of the total phenotypic variation, respectively. Three significant QTLs （qPOG-2, qPOG-3 and qPOG-7） were identified and mapped on chromosomes 2, 3, and 7, respectively. These QTLs contributed 9.6, 6.7, and 17.8% of phenotypic variations, respectively. A comparative analysis using SSR markers closely linked to the three QTLs for the overwintering revealed cold-tolerant individuals, which harbour the Glutinous rice 89-1 alleles at RM7110, RM250, RM418, and RM232, had a high percent overwintering germinability, while cold-sensitive individuals, which carry Shuhui 527 alleles at these loci, had a low percent overwintering germinability in the F2 population of Shuhui 527/Glutinous rice 89-1. This study demonstrated the utility of these SSR markers for selection of overwintering germinability genotypes.展开更多
Phytosulfokine- α （PSK- α ）, a biologically active peptide acting as a growth factor, plays a key role in cellular differentiation and proliferation. To test if PSK- α has some influence on agrobacterium-mediated...Phytosulfokine- α （PSK- α ）, a biologically active peptide acting as a growth factor, plays a key role in cellular differentiation and proliferation. To test if PSK- α has some influence on agrobacterium-mediated transformation in rice, PSK-α at a series of concentrations was added into co-culture medium respectively. The results showed that PSK- α indeed affected the recovery of resistant calli and the transformation frequency of rice varieties Taipei 309 and Lijiangxintuanheigu, PSK- α at the concentration of 10 nmol/L could increase induction of resistant callus and efficiency of transformation, with a 11% and 4.9% top increase, respectively than the control. However, PSK- αat 200 nmol/L could inhibit the induction of the resistant calli. Further more, the effect of PSK-α on agrobacterium-mediated transformation is related with the concentration of 2, 4-D in selection medium. Higher induction rate of resistant calli was obtained from tissues treated with PSK- α plus 2 mg/L 2, 4-D.展开更多
Background Total knee arthroplasties （TKR） combined with the concept of reduced trauma to tissue has been performed by many doctors. The aim of this study was to retrospectively assess the early results of a group o...Background Total knee arthroplasties （TKR） combined with the concept of reduced trauma to tissue has been performed by many doctors. The aim of this study was to retrospectively assess the early results of a group of TKR with a mid-vastus approach, which was characterized as no patellar eversion, no disruption of suprapatellar pouch and extensor mechanism, and to compare the outcome with conventional operative techniques. Methods A total of 59 patients （67 knees） were followed. All patients received the same prosthesis of Genesis II posterior-stabilized total knees. Of them, 29 consecutive patients （34 knees） had a mid-vastus approach and were operated on with less invasive instruments and techniques. The mean follow-up duration was 11.6 months. Clinical evaluations were performed according to the Hospital for Special Surgery scores; radiographic assessment followed the guidelines of the Knee Society. Postoperative recovery of quadriceps strength and the extensor mechanism was also evaluated. Results No prosthetic loosening or anterior knee pain was found at the latest follow-up; 1 patient had a superficial infection and postoperative stiffness of the knee who undertook a debridement and manipulation several months later. The angulations of tibial osteotomy were within normal range. The average preoperative and postoperative Hospital for Special Surgery scores were 57.9 points and 86.1 points respectively. The mean postoperative range of motion was 113.5^-. Most patients regained their quadriceps strength at the third or fourth month postoperatively. Conclusions The overall early results from using the mid-vastus approach were comparable with that of using a standard approach, and the exposure did not affect the accuracy of the tibial cut. The muscle maximal contraction strenath recovered araduallv after oDeration. The aDDroach was safe and Datients of this aroup obtained satisfactorv outcomes.展开更多
The mechanism of early generation stability （EGS） in rice was studied via genetic analysis. Three types of crosses were made, namely between EGS varieties, EGS and conventional rice variety, and conventional rice va...The mechanism of early generation stability （EGS） in rice was studied via genetic analysis. Three types of crosses were made, namely between EGS varieties, EGS and conventional rice variety, and conventional rice varieties. The genetic analysis was based on the stable lines in F2 population. The stable lines may appear from some combinations of EGS rice crossing with each other and EGS rice crossing with conventional varieties at different frequencies, but stable lines didn＇t appear in conventional varieties crossing with conventional varieties. Genetic analysis results indicated that the EGS phenomena should just exist in special rice materials, and the frequency of stable lines was closely related to the EGS traits of parents. The EGS traits were neither qualitative nor quantitative traits, and they were controlled by neither dominant genes nor recessive genes. The EGS traits might be inherited by F1 single plant, and the traits of F3 and F4 were corresponded to those of F2 population, i.e. F3 and F4 lines derived from non-segregating F2 showed uniform agronomic traits, and those from segregating F2.did not. The agronomic traits of EGS lines were consistent with those of F1 single plant. On the other hand, when EGS lines occurred, the segregating lines in Mendelian manner were also observed in all F2 population of the same combination. It was suggested that the reason why the stable strains occurred might be a special factor to control （open/close） gene at the beginning of cell division in zygote, resulting in closing mitosis and opening somatic reduction. The somatic reduction of zygote resulted in recombination and homozygosity forming in F1 single plant, and some lines with uniform agronomic traits were observed in some lines of F2 population.展开更多
A double mutant with streaked leaf and abnormal floret was found and temporarily named streaked leaf and floral organ number mutant （st-fon）. For this mutant, besides white streak appeared on culm, leaves and panicl...A double mutant with streaked leaf and abnormal floret was found and temporarily named streaked leaf and floral organ number mutant （st-fon）. For this mutant, besides white streak appeared on culm, leaves and panicles, the number of floral organs increased and florets cracked. The extreme phenotype was that several small florets grew from one floret or branch rachis in small florets extended and developed into panicles. By using transmission electron microscope to observe the ultrastructure of white histocytes of leaves at the seedling stage, the white tissues which showed abnormal plastids, lamellas and thylakoids could not develop into normal chloroplast, and the development of chloroplast was blocked at the early growth stage of plastid. Scanning electron microscope and paraffin section were also used to observe the development of floral organs, and the results indicated that the development of floral meristem was out of order and unlimited, whereas in the twisty leaves, vascular bundle sheath cells grew excessively, or some bubbly cells increased. Genetic analyses carried out by means of cross and backcross with four normal-leaf-color materials revealed that the mutant is of cytoplasm inheritance.展开更多
Resistance to rice blast of transgenic rice lines harboring rice blast resistance gene Pi-d2 transformed from three different expression vectors of pCB6.3kb, pCB5.3kb and pZH01-2.72kb were analyzed. Nine advanced-gene...Resistance to rice blast of transgenic rice lines harboring rice blast resistance gene Pi-d2 transformed from three different expression vectors of pCB6.3kb, pCB5.3kb and pZH01-2.72kb were analyzed. Nine advanced-generation transgenic rice lines with Pi-d2 gene displayed various resistance to 39 rice blast strains, and the highest disease-resistant frequency reached 91.7%. Four early-generation homozygous transgenic lines with Pi-d2 gene exhibited resistance to more than 81.5% of 58 rice blast strains, showing the characteristic of wide-spectrum resistance. The transgenic embryonic calli selected by the crude toxin of rice blast fungus showed that the callus induction rate of immature embryo from transgenic rice plants decreased as the concentration of crude toxin in the culture medium increased. When the concentration of crude toxin reached 40%, the callus induction rate of immature embryo from transgenic lines was 49.3%, and that of the receptor control was 5%. The disease incidence of neck blast of the transgenic rice lines in fields under induction was 0% to 50%, indicating that the rice blast resistance of transgenic rice lines is much higher than that of the receptor control.展开更多
This article discusses the overwintering ability and genetic variation of the main agronomic traits in a new germplasm resource, glutinous rice 89-1. Survival rates of overwintering axillary buds and stems were observ...This article discusses the overwintering ability and genetic variation of the main agronomic traits in a new germplasm resource, glutinous rice 89-1. Survival rates of overwintering axillary buds and stems were observed in different altitudes. The F1, backcross F1 and F2 populations were constructed from sexual crossing between glutinous rice 89-1 and Hongmangnuo, Fuhui 838, Minghui 63, Ce 64. The overwintering ability and genetic variation of the main agronomic traits were analyzed in different seasons. Results showed that glutinous rice 89-1 could overwinter by axillary buds in low temperatures at different altitudes. Axillary buds would ratoon in the following year. The survival rates of rice stem and axillary buds were 82.6 and 29%, respectively. The grain yields were 6 291.0 kg ha^-1 in the overwintering ratooning season, and corresponded in the main season. Genetic analysis and chi-square test showed that the overwintering ability of glutinous rice 89-1 was likely controlled by polygene, and heritabilities showed diversity in different hybrid combinations. The highest heritabilities of 1 000-grain weight and plant height were in the main crop season, whereas the lowest were in the overwintering season, and the heritabilities of grain numbers per panicle and the seed setting rate reached the highest in the ratooning season. The spikelets per panicle, the seed setting rate, the 1 000-grain weight, the plant height, and the spikelet length had nearly normal distribution in F2 populations of glutinous rice 89-1/Minghui 63, but the seed setting rate had bimodal distribution. Overwintering glutinous rice 89-1 was a useful new genetic germplasm resource.展开更多
Glucose is vital to embryogenesis,as are glucose transporters.Glucose transporter 4(Glut4)is one of the glucose transporters,which is involved in rapid uptake of glucose by various cells and promotes glucose homeostas...Glucose is vital to embryogenesis,as are glucose transporters.Glucose transporter 4(Glut4)is one of the glucose transporters,which is involved in rapid uptake of glucose by various cells and promotes glucose homeostasis.Although energy metabolism in insect reproduction is well known,the molecular mechanism of Glut4 in insect reproduction is poorly understood.We suspect that Glut4 is involved in maintaining glucose concentrations in the ovaries and affecting vitellogenesis,which is critical for subsequent oocyte maturation and insect fertility.Harmonia axyridis(Pallas)is a model organism for genetic research and a natural enemy of insect pests.We studied the influence of the Glut4 gene on the reproduction and development of H.axyridis using RNA interference technology.Reverse transcription quantitative polymerase chain reaction analysis revealed that HaGlut4 was most highly expressed in adults.Knockdown of the HaGlut4 gene reduced the transcript levels of HaGlut4,and the weight and number of eggs produced significantly decreased.In addition,the transcript levels of vitellogenin receptor and vitellogenin in the fat bodies and the ovaries of H.axyridis decreased after the interference of Glut4,and decreased the triglyceride,fatty acid,total amino acid and adenosine triphosphate content of H.axyridis.This resulted in severe blockage of ovary development and reduction of yolk formation;there was no development of ovarioles in the developing oocytes.These changes indicate that a lack of HaGlut4 can impair ovarian development and oocyte maturation and result in decreased fecundity.展开更多
基金supported by the Excellent Doctor Paper Foundation of the Ministry of Education of China (Grant No.200054)the Program for Innovative Research Team in University of China (Grant No.NCET-04-0907)the Program for New Century Excellent Talent in University of China (Grant No.IRT0453)
文摘The gene Pi-d2, conferring gene-for-gene resistance to the Chinese blast strain ZB15, was isolated from a rice variety （Digu） by the map-based cloning strategy. Here, we constructed a control plasmid pZH01-pi-d2tp309 （pZH01-tp309） and three different expression constructs, pCB-Pi-d25.3kb （pCB5.3kb）, pCB-Pi-d26.3kb （pCB6.3kb） and pZH01-Pi-d22.72kb （pZH01-2.72kb） of Pi-d2, driven by Pi-d2 gene’s own promoter or CaMV35S promoter. These constructs were separately introduced into japonica rice varieties Lijiangxintuanhegu, Taipei 309, Nipponbare and Zhonghua 9 through Agrobacterium- mediated transformation. A total of 150 transgenic rice plants were obtained from the regenerated calli selected on hygromycin. PCR, RT-PCR and Southern-blotting assay showed that the gene of interest had been integrated into rice genome and stably inherited. Thirty-five transgenic lines independently derived from T1 progeny were inoculated with the rice blast strain ZB15. Transformants exhibited resistance to rice blast at various levels. The lesions on the transgenic plant leaves were less severe than those on the controls and the resistance level of transgenic plants harboring the gene of interest from three vectors had no difference. The own promoter of Pi-d2, about 2.2 kb or 3.2 kb, had the similar promoter function as CaMV35S. Field evaluation for three successive years supported the results of artificial trial, and some lines with high resistance to rice leaf blast and neck blast were obtained.
基金This work wassupported by grants from the Ministry of Health of the People＇s Republic of China, the World Health Organization for the clinical study of the influenza A pandemic A （H1N1） 2009 and the National Natural Science Foundation of China （No. 81030032 and No. 81070005）.Acknowledgements： The authors gratefully acknowledge the following individuals who helped identifying cases and collated clinical data： SONG Shu-fan, LI Ran, YANG Ting, YIN Yu-dong, MA Chen, and BAI Lu who participated in the collection of clinical data Hui David Shu-Cheong （Hong Kong, China）, Colin James McArthur （New Zealand）, Dale Andrew Fisher （Singapore）, OH Myoung Don （Korea）, Dong Jie （World Health Organization） who provided technical support XIAO Fei and WU Si-nan who help reviewing the manuscript.
文摘Background The 2009 pandemic H1 N1 （pH1N1） influenza showed that relatively young adults accounted for the highest rates of hospital admission and death.In preparation for pH1N1,the aim of the study is to identify factors associated with the mortality of patients with 2009 pH1N1 infection,especially for young patients without chronic medical conditions.Methods Retrospective observational study of 2151 severe or critical adult cases （-≥14 years old） admitted to a hospital with pH1N1 influenza from September 1,2009 to December 31,2009 from 426 hospitals of 27 Chinese provinces.A confirmed case was a person whose pH1N1 virus infection was verified by real-time reverse-transcriptase polymerase chain reaction （rRT-PCR）.Severe and critical cases were defined according to the H1N1 2009 Clinical guidelines （Third Edition,2009） released by the Ministry of Health of China.Results Among the 2151 patients,the mean age was 34.0 years.Two hundred and ninty-three （13.6%） died during hospital stay.One thousand four hundred and forty-two patients （67.0%） had no comorbidities and 189 （13.1%） of them died.Pregnancy （OR 8.03）,pneumonia （OR 8.91）,dyspnea （OR 3.95）,central nervous system （CNS） symptom （OR 1.55）,higher APACHE （Acute Physiology and Chronic Health Evaluation） Ⅱ score （OR 1.06）,Alanine aminotransferase （ALT） （OR 1.002）,and the lactate dehydrogenase （LDH） level （OR 1.001） were independent risk factors for death among adults without chronic medical conditions.Higher APACHE Ⅱ score （OR 1.08） and age （OR 1.06） were independent risk factors for death among adults with respiratory diseases.A multivariate analysis showed an association between mortality and CNS symptoms （OR 2.66）,higher APACHE Ⅱ score （OR 1.03）,ALT （OR 1.006）,and LDH level （OR 1.002） in patients with cardiovascular diseases.Dyspnea （OR 11.32） was an independent risk factor for patient death in patients with diabetes mellitus.Conclusion Clinical knowledge o
基金supported by the Rice Key Project of Chongqing,China (CSTC2011AB1076)the Foundation Project of Chongqing Education Commission (KJ110623)+1 种基金the Doctor Foundation of Chongqing Normal University,China (10LR028)the Plants Breeding Project of Chongqing,China (CSTC2010AA1033)
文摘312 recombinant inbred lines （RILs） in F9 from a cross between a overwintering cold-tolerant germplasm resource Glutinous rice 89-1（Gr 89-1） and a cold-sensitive variety Shuhui 527 was used for quantitative trait locus （QTL） analysis. The scores of percent ratooning germinability （PRG） and overwintering germinability （POG） were evaluated. The overwintering germination rate of axillary buds was scored to represent the overwintering germinability. Two significant QTLs （qPRG-4 and qPRG-7） on chromosomes 4 and 7 were detected and explained 8.3 and 7.2% of the total phenotypic variation, respectively. Three significant QTLs （qPOG-2, qPOG-3 and qPOG-7） were identified and mapped on chromosomes 2, 3, and 7, respectively. These QTLs contributed 9.6, 6.7, and 17.8% of phenotypic variations, respectively. A comparative analysis using SSR markers closely linked to the three QTLs for the overwintering revealed cold-tolerant individuals, which harbour the Glutinous rice 89-1 alleles at RM7110, RM250, RM418, and RM232, had a high percent overwintering germinability, while cold-sensitive individuals, which carry Shuhui 527 alleles at these loci, had a low percent overwintering germinability in the F2 population of Shuhui 527/Glutinous rice 89-1. This study demonstrated the utility of these SSR markers for selection of overwintering germinability genotypes.
文摘Phytosulfokine- α （PSK- α ）, a biologically active peptide acting as a growth factor, plays a key role in cellular differentiation and proliferation. To test if PSK- α has some influence on agrobacterium-mediated transformation in rice, PSK-α at a series of concentrations was added into co-culture medium respectively. The results showed that PSK- α indeed affected the recovery of resistant calli and the transformation frequency of rice varieties Taipei 309 and Lijiangxintuanheigu, PSK- α at the concentration of 10 nmol/L could increase induction of resistant callus and efficiency of transformation, with a 11% and 4.9% top increase, respectively than the control. However, PSK- αat 200 nmol/L could inhibit the induction of the resistant calli. Further more, the effect of PSK-α on agrobacterium-mediated transformation is related with the concentration of 2, 4-D in selection medium. Higher induction rate of resistant calli was obtained from tissues treated with PSK- α plus 2 mg/L 2, 4-D.
文摘Background Total knee arthroplasties （TKR） combined with the concept of reduced trauma to tissue has been performed by many doctors. The aim of this study was to retrospectively assess the early results of a group of TKR with a mid-vastus approach, which was characterized as no patellar eversion, no disruption of suprapatellar pouch and extensor mechanism, and to compare the outcome with conventional operative techniques. Methods A total of 59 patients （67 knees） were followed. All patients received the same prosthesis of Genesis II posterior-stabilized total knees. Of them, 29 consecutive patients （34 knees） had a mid-vastus approach and were operated on with less invasive instruments and techniques. The mean follow-up duration was 11.6 months. Clinical evaluations were performed according to the Hospital for Special Surgery scores; radiographic assessment followed the guidelines of the Knee Society. Postoperative recovery of quadriceps strength and the extensor mechanism was also evaluated. Results No prosthetic loosening or anterior knee pain was found at the latest follow-up; 1 patient had a superficial infection and postoperative stiffness of the knee who undertook a debridement and manipulation several months later. The angulations of tibial osteotomy were within normal range. The average preoperative and postoperative Hospital for Special Surgery scores were 57.9 points and 86.1 points respectively. The mean postoperative range of motion was 113.5^-. Most patients regained their quadriceps strength at the third or fourth month postoperatively. Conclusions The overall early results from using the mid-vastus approach were comparable with that of using a standard approach, and the exposure did not affect the accuracy of the tibial cut. The muscle maximal contraction strenath recovered araduallv after oDeration. The aDDroach was safe and Datients of this aroup obtained satisfactorv outcomes.
基金China Natural Science Foundation(30001037) Youth Foundation of Sichuan Province,China.
文摘The mechanism of early generation stability （EGS） in rice was studied via genetic analysis. Three types of crosses were made, namely between EGS varieties, EGS and conventional rice variety, and conventional rice varieties. The genetic analysis was based on the stable lines in F2 population. The stable lines may appear from some combinations of EGS rice crossing with each other and EGS rice crossing with conventional varieties at different frequencies, but stable lines didn＇t appear in conventional varieties crossing with conventional varieties. Genetic analysis results indicated that the EGS phenomena should just exist in special rice materials, and the frequency of stable lines was closely related to the EGS traits of parents. The EGS traits were neither qualitative nor quantitative traits, and they were controlled by neither dominant genes nor recessive genes. The EGS traits might be inherited by F1 single plant, and the traits of F3 and F4 were corresponded to those of F2 population, i.e. F3 and F4 lines derived from non-segregating F2 showed uniform agronomic traits, and those from segregating F2.did not. The agronomic traits of EGS lines were consistent with those of F1 single plant. On the other hand, when EGS lines occurred, the segregating lines in Mendelian manner were also observed in all F2 population of the same combination. It was suggested that the reason why the stable strains occurred might be a special factor to control （open/close） gene at the beginning of cell division in zygote, resulting in closing mitosis and opening somatic reduction. The somatic reduction of zygote resulted in recombination and homozygosity forming in F1 single plant, and some lines with uniform agronomic traits were observed in some lines of F2 population.
基金supported by the Foundation Program,Innovative Team Development Plan of the Ministry of Education,China(Grant No.IRT0453)the Financial Gene Engineering Excellent Article Foundation Program of Sichuan Province,China(Grant No.2011LWJJ-005)
文摘A double mutant with streaked leaf and abnormal floret was found and temporarily named streaked leaf and floral organ number mutant （st-fon）. For this mutant, besides white streak appeared on culm, leaves and panicles, the number of floral organs increased and florets cracked. The extreme phenotype was that several small florets grew from one floret or branch rachis in small florets extended and developed into panicles. By using transmission electron microscope to observe the ultrastructure of white histocytes of leaves at the seedling stage, the white tissues which showed abnormal plastids, lamellas and thylakoids could not develop into normal chloroplast, and the development of chloroplast was blocked at the early growth stage of plastid. Scanning electron microscope and paraffin section were also used to observe the development of floral organs, and the results indicated that the development of floral meristem was out of order and unlimited, whereas in the twisty leaves, vascular bundle sheath cells grew excessively, or some bubbly cells increased. Genetic analyses carried out by means of cross and backcross with four normal-leaf-color materials revealed that the mutant is of cytoplasm inheritance.
基金supported by the Program for Supporting New-century Excellent Talents of Ministry of Education, China (Grant No. NCET-04-0907)the Program for Supporting Development of Innovative Research Teams of Ministry of Education, China (Grant No. IRT0453)the Applied Basic Research Program of Sichuan Province, China (Grant No. 2008JY0023-1)
文摘Resistance to rice blast of transgenic rice lines harboring rice blast resistance gene Pi-d2 transformed from three different expression vectors of pCB6.3kb, pCB5.3kb and pZH01-2.72kb were analyzed. Nine advanced-generation transgenic rice lines with Pi-d2 gene displayed various resistance to 39 rice blast strains, and the highest disease-resistant frequency reached 91.7%. Four early-generation homozygous transgenic lines with Pi-d2 gene exhibited resistance to more than 81.5% of 58 rice blast strains, showing the characteristic of wide-spectrum resistance. The transgenic embryonic calli selected by the crude toxin of rice blast fungus showed that the callus induction rate of immature embryo from transgenic rice plants decreased as the concentration of crude toxin in the culture medium increased. When the concentration of crude toxin reached 40%, the callus induction rate of immature embryo from transgenic lines was 49.3%, and that of the receptor control was 5%. The disease incidence of neck blast of the transgenic rice lines in fields under induction was 0% to 50%, indicating that the rice blast resistance of transgenic rice lines is much higher than that of the receptor control.
文摘This article discusses the overwintering ability and genetic variation of the main agronomic traits in a new germplasm resource, glutinous rice 89-1. Survival rates of overwintering axillary buds and stems were observed in different altitudes. The F1, backcross F1 and F2 populations were constructed from sexual crossing between glutinous rice 89-1 and Hongmangnuo, Fuhui 838, Minghui 63, Ce 64. The overwintering ability and genetic variation of the main agronomic traits were analyzed in different seasons. Results showed that glutinous rice 89-1 could overwinter by axillary buds in low temperatures at different altitudes. Axillary buds would ratoon in the following year. The survival rates of rice stem and axillary buds were 82.6 and 29%, respectively. The grain yields were 6 291.0 kg ha^-1 in the overwintering ratooning season, and corresponded in the main season. Genetic analysis and chi-square test showed that the overwintering ability of glutinous rice 89-1 was likely controlled by polygene, and heritabilities showed diversity in different hybrid combinations. The highest heritabilities of 1 000-grain weight and plant height were in the main crop season, whereas the lowest were in the overwintering season, and the heritabilities of grain numbers per panicle and the seed setting rate reached the highest in the ratooning season. The spikelets per panicle, the seed setting rate, the 1 000-grain weight, the plant height, and the spikelet length had nearly normal distribution in F2 populations of glutinous rice 89-1/Minghui 63, but the seed setting rate had bimodal distribution. Overwintering glutinous rice 89-1 was a useful new genetic germplasm resource.
基金This work was supported by the National Key Research and Development Program of China(Grant No.2017YFD0201000)the Hangzhou Science and Technology Development Program of China(Grant No.20190101A01).
文摘Glucose is vital to embryogenesis,as are glucose transporters.Glucose transporter 4(Glut4)is one of the glucose transporters,which is involved in rapid uptake of glucose by various cells and promotes glucose homeostasis.Although energy metabolism in insect reproduction is well known,the molecular mechanism of Glut4 in insect reproduction is poorly understood.We suspect that Glut4 is involved in maintaining glucose concentrations in the ovaries and affecting vitellogenesis,which is critical for subsequent oocyte maturation and insect fertility.Harmonia axyridis(Pallas)is a model organism for genetic research and a natural enemy of insect pests.We studied the influence of the Glut4 gene on the reproduction and development of H.axyridis using RNA interference technology.Reverse transcription quantitative polymerase chain reaction analysis revealed that HaGlut4 was most highly expressed in adults.Knockdown of the HaGlut4 gene reduced the transcript levels of HaGlut4,and the weight and number of eggs produced significantly decreased.In addition,the transcript levels of vitellogenin receptor and vitellogenin in the fat bodies and the ovaries of H.axyridis decreased after the interference of Glut4,and decreased the triglyceride,fatty acid,total amino acid and adenosine triphosphate content of H.axyridis.This resulted in severe blockage of ovary development and reduction of yolk formation;there was no development of ovarioles in the developing oocytes.These changes indicate that a lack of HaGlut4 can impair ovarian development and oocyte maturation and result in decreased fecundity.
