[Objective] This study aimed to investigate the correlation between stigma characteristics and outcrossing rate of photo-thermo sensitive genic male sterile（PTGMS） rice lines. [Method] The stigma exsertion rate, sti...[Objective] This study aimed to investigate the correlation between stigma characteristics and outcrossing rate of photo-thermo sensitive genic male sterile（PTGMS） rice lines. [Method] The stigma exsertion rate, stigma size and stigma vitality of Chuang 5S, Yun 9S, Peiai 64 S, P88 S and Y58 S were analyzed. Using R608 as a male parent, outcrossing rate of these five PTGMS lines was determined. [Result]There were differences in stigma exsertion rate, stigma size and stigma vitality among five PTGMS lines. P88 S exhibited the best stigma characteristics and relatively strong stigma vitality, with the stigma exsertion rate of 95.94%, stigma vitality coefficient of 2.71, outcrossing rate of 84.02% in the field. Peiai 64 s had the minimum stigma length（2.41 mm） and stigma width（1.10 mm） and the weakest stigma vitality, with the stigma exsertion rate of 93.04%, outcrossing rate of 65.47%. Yun 9S,Y58 S and Chuang 5S displayed medium stigma characteristics, among which Yun9 S exhibited higher outcrossing rate than other two PTGMS lines. Correlation analysis showed that stigma exsertion rate, stigma length, stigma width, stigma area and stigma volume were significantly correlated to outcrossing rate（P〈0.05）, with correlation coefficients of 0.897, 0.934, 0.934, 0.939 and 0.937, respectively. However,there was no significant correlation between stigma vitality coefficient and outcrossing rate. [Conclusion] Based on stigma characteristics of five PTGMS lines, auxiliary pollination measures should be adopted reasonably to save production costs and improve hybrid rice seed yield.展开更多
[Objective] To breed and utilize the japonicalinous cytoplasmic male sterile （CMS） line Chunjiang 19A with wide compatibility and high outcrossing rate. [Method] Cbunjiang 16A was used as the female parent to cross ...[Objective] To breed and utilize the japonicalinous cytoplasmic male sterile （CMS） line Chunjiang 19A with wide compatibility and high outcrossing rate. [Method] Cbunjiang 16A was used as the female parent to cross with Indica-Japonica crossing material B125, which was used as male parent. Backcross breeding was contin- ued for consecutive generations to breed the CMS lines with wide compatibility and high outcrossing rate. [Result] Chunjiang 19A is a late medium Japonica CMS line with good fertility stability. The proportion of sterile plants and pollen abortion rates are 100% and the Cheng＇s index is 14. It is the japonicalinous CMS line with early flowering, partial stigma exsertion, high outcrossing rate, wide compatibility, high re- sistance to stripe disease and good combining ability. The hybrid rice combinations originated from Chunjiang 19A have strong tUlering ability, dominant heterosis, high resistance to stripe disease, great yield potential and good color change at mature stage. [Conclusion] The successful breeding of Chunjiang 19A laid good foundation for the breeding of Japonica hybrid rice and Indica-Japonica hybrid rice combinations with high seed production and dominant heterosis, showing a promising application prospect.展开更多
Four pairs of microsatellite molecular polymorphism primers were used to analyse microsatellite fingerprints of 188 seedlings derived from an open-pollinated progeny grafted Eucalyptus globulus breeding arboretum in V...Four pairs of microsatellite molecular polymorphism primers were used to analyse microsatellite fingerprints of 188 seedlings derived from an open-pollinated progeny grafted Eucalyptus globulus breeding arboretum in Victoria, south-eastern Australia. The microsatellite loci chosen for this study were highly polymorphic with the mean number of alleles per locus of 14.25. Individual mothers varied in their outcrosssing rate estimate from 15% to 95%, the overall outcrossing level in the arboretum was 47.9% and the contamination rate was 17.6%. The high selfing level was likely to result in marked inbreeding depression in the performance of open-pollinated seed lots. Open-pollinated seeds collected from such arboreta are not advisable because of its low genetic quality, although such arboreta may be useful for the seed production through large-scale manual pollination or collecting seeds only from trees or genotypes within the arboretum that have high outcrossing rates.展开更多
Outcrossing rate is an important determinant of cytoplasmic male sterile(CMS)breeding and hybrid seed production for heterosis in soybean.Parental lines with a high outcrossing rate were screened for backcross breedin...Outcrossing rate is an important determinant of cytoplasmic male sterile(CMS)breeding and hybrid seed production for heterosis in soybean.Parental lines with a high outcrossing rate were screened for backcross breeding to obtain the high outcrossing rate maintenance B-lines and sterile A-lines.Application in production practices will help to increase hybrid soybean production.In this study,JLCMS82B and JLCMS89B were selected as parents for the construction of outcrossing rate segregation populations,and the progeny-array approach(PAA)and glyphosate resistant gene markers were used to determine outcrossing rates.We found that:(1)The outcrossing rate between JLCMS82B and JLCMS89B was significantly different;(2)the outcrossing rate of the F2 segregating populations was a quantitative trait,though whether an additive or epistatic effect exists required analysis with a triple test intersection analysis;(3)agronomic traits correlated with outcrossing rate;outcrossing rate was the highest with plant height of about 84 cm,lower number of plant branches,earlier flowering time,larger angle between the branches and the main stem,and with more divergent plant morphology.Correlation analysis between agronomic traits and outcrossing rate can effectively guide the screening of parents with a high outcrossing rate.展开更多
Using photo-thermo sensitive genie male rice (PTGMS) Pei' ai 64S, W7415S, W6154S, N26S, Annong S, Nongken 58S, 7001S and 5088S as female parents and conventional indica lines 8258 and U89 as male parents, the fact...Using photo-thermo sensitive genie male rice (PTGMS) Pei' ai 64S, W7415S, W6154S, N26S, Annong S, Nongken 58S, 7001S and 5088S as female parents and conventional indica lines 8258 and U89 as male parents, the factors affecting outcrossed seed-setting were analyzed. The PTGMS had obstacles in outcrossed seed setting influenced by inheritance and environment at varying degrees. Environmental temperature was regarded as the main factor that resulted in the outcrossed seed-setting obstacles. The sensitive stage was at the early stage of grain filling for outcrossed seed setting. There existed remarkable differences at the sensitivity stage, the duration of sensitive period, the sensitive level and the effective level of outcrossed seed-setting obstacles caused by environmental temperature among different PTGMS lines. Therefore, attention should be paid to outcrossed seed-setting obstacles in selection and utilization of PTGMS lines.展开更多
基金Supported by National Science and Technology Support Program of China(2014BAD06B07)~~
文摘[Objective] This study aimed to investigate the correlation between stigma characteristics and outcrossing rate of photo-thermo sensitive genic male sterile（PTGMS） rice lines. [Method] The stigma exsertion rate, stigma size and stigma vitality of Chuang 5S, Yun 9S, Peiai 64 S, P88 S and Y58 S were analyzed. Using R608 as a male parent, outcrossing rate of these five PTGMS lines was determined. [Result]There were differences in stigma exsertion rate, stigma size and stigma vitality among five PTGMS lines. P88 S exhibited the best stigma characteristics and relatively strong stigma vitality, with the stigma exsertion rate of 95.94%, stigma vitality coefficient of 2.71, outcrossing rate of 84.02% in the field. Peiai 64 s had the minimum stigma length（2.41 mm） and stigma width（1.10 mm） and the weakest stigma vitality, with the stigma exsertion rate of 93.04%, outcrossing rate of 65.47%. Yun 9S,Y58 S and Chuang 5S displayed medium stigma characteristics, among which Yun9 S exhibited higher outcrossing rate than other two PTGMS lines. Correlation analysis showed that stigma exsertion rate, stigma length, stigma width, stigma area and stigma volume were significantly correlated to outcrossing rate（P〈0.05）, with correlation coefficients of 0.897, 0.934, 0.934, 0.939 and 0.937, respectively. However,there was no significant correlation between stigma vitality coefficient and outcrossing rate. [Conclusion] Based on stigma characteristics of five PTGMS lines, auxiliary pollination measures should be adopted reasonably to save production costs and improve hybrid rice seed yield.
基金Supported by the National High Technology Research and Development Program ofChina (863 Program) (2010AA101301)the Program of Breeding and Experimental Demonstration of Super Hybrid Rice in China from Ministry of Agriculture+1 种基金the 0406 Program of Zhejiang Provincethe Fundamental Research Fund of China National RiceResearch Institute (2009RG001-5)~~
文摘[Objective] To breed and utilize the japonicalinous cytoplasmic male sterile （CMS） line Chunjiang 19A with wide compatibility and high outcrossing rate. [Method] Cbunjiang 16A was used as the female parent to cross with Indica-Japonica crossing material B125, which was used as male parent. Backcross breeding was contin- ued for consecutive generations to breed the CMS lines with wide compatibility and high outcrossing rate. [Result] Chunjiang 19A is a late medium Japonica CMS line with good fertility stability. The proportion of sterile plants and pollen abortion rates are 100% and the Cheng＇s index is 14. It is the japonicalinous CMS line with early flowering, partial stigma exsertion, high outcrossing rate, wide compatibility, high re- sistance to stripe disease and good combining ability. The hybrid rice combinations originated from Chunjiang 19A have strong tUlering ability, dominant heterosis, high resistance to stripe disease, great yield potential and good color change at mature stage. [Conclusion] The successful breeding of Chunjiang 19A laid good foundation for the breeding of Japonica hybrid rice and Indica-Japonica hybrid rice combinations with high seed production and dominant heterosis, showing a promising application prospect.
基金This study was supported by State Administration of Foreign Experts Affairs, P. R. China (No.2001430007)
文摘Four pairs of microsatellite molecular polymorphism primers were used to analyse microsatellite fingerprints of 188 seedlings derived from an open-pollinated progeny grafted Eucalyptus globulus breeding arboretum in Victoria, south-eastern Australia. The microsatellite loci chosen for this study were highly polymorphic with the mean number of alleles per locus of 14.25. Individual mothers varied in their outcrosssing rate estimate from 15% to 95%, the overall outcrossing level in the arboretum was 47.9% and the contamination rate was 17.6%. The high selfing level was likely to result in marked inbreeding depression in the performance of open-pollinated seed lots. Open-pollinated seeds collected from such arboreta are not advisable because of its low genetic quality, although such arboreta may be useful for the seed production through large-scale manual pollination or collecting seeds only from trees or genotypes within the arboretum that have high outcrossing rates.
基金supported by the National Natural Science Foundation for Young Scientists of China (31301399)the Major Project for Science and Technology Development of Jilin Province, China (20170201001NY)the Agricultural Science Technology Innovation Project of Jilin Province, China (CXGC2017TD002)
文摘Outcrossing rate is an important determinant of cytoplasmic male sterile(CMS)breeding and hybrid seed production for heterosis in soybean.Parental lines with a high outcrossing rate were screened for backcross breeding to obtain the high outcrossing rate maintenance B-lines and sterile A-lines.Application in production practices will help to increase hybrid soybean production.In this study,JLCMS82B and JLCMS89B were selected as parents for the construction of outcrossing rate segregation populations,and the progeny-array approach(PAA)and glyphosate resistant gene markers were used to determine outcrossing rates.We found that:(1)The outcrossing rate between JLCMS82B and JLCMS89B was significantly different;(2)the outcrossing rate of the F2 segregating populations was a quantitative trait,though whether an additive or epistatic effect exists required analysis with a triple test intersection analysis;(3)agronomic traits correlated with outcrossing rate;outcrossing rate was the highest with plant height of about 84 cm,lower number of plant branches,earlier flowering time,larger angle between the branches and the main stem,and with more divergent plant morphology.Correlation analysis between agronomic traits and outcrossing rate can effectively guide the screening of parents with a high outcrossing rate.
文摘Using photo-thermo sensitive genie male rice (PTGMS) Pei' ai 64S, W7415S, W6154S, N26S, Annong S, Nongken 58S, 7001S and 5088S as female parents and conventional indica lines 8258 and U89 as male parents, the factors affecting outcrossed seed-setting were analyzed. The PTGMS had obstacles in outcrossed seed setting influenced by inheritance and environment at varying degrees. Environmental temperature was regarded as the main factor that resulted in the outcrossed seed-setting obstacles. The sensitive stage was at the early stage of grain filling for outcrossed seed setting. There existed remarkable differences at the sensitivity stage, the duration of sensitive period, the sensitive level and the effective level of outcrossed seed-setting obstacles caused by environmental temperature among different PTGMS lines. Therefore, attention should be paid to outcrossed seed-setting obstacles in selection and utilization of PTGMS lines.
