Shoot-tip culture of strawberry is the most important way to get virus-free plants.Moreover,detoxification and rapid propagation are the key techniques for producing high-quality seeds and seedlings massively and rapi...Shoot-tip culture of strawberry is the most important way to get virus-free plants.Moreover,detoxification and rapid propagation are the key techniques for producing high-quality seeds and seedlings massively and rapidly and achieving the high-quality,high-yield and high-efficiency development of strawberry industry.We have recently produced virus-free strawberry seedlings by combing tissue culture technology and stolon-reproduction method and this technology has been widely used.In addition,a relatively perfect three breeding system of virus-free strawberry seedlings was established after production practices,guaranteeing the supply of high-quality seeds and seedlings and technical support for strawberry industry in corps.展开更多
In order to improve the frequency of indica rice transformation by biolistic bombardment, suitable culture conditions for embryonic calli,an optimal selection scheme for resistant calli and seedlings, and optimum bomb...In order to improve the frequency of indica rice transformation by biolistic bombardment, suitable culture conditions for embryonic calli,an optimal selection scheme for resistant calli and seedlings, and optimum bombardment parameters a investigated by using 14 commercially important indica rice cultivars. The main results show that the CC medium with 36g/L mannitol is a scheme subculture medium in which the browning of indica rice calli can be mitigated significantly; The concentration of 30～40mg/L Hyg or 150～200mg/L G418 or 10～20 mg/L Basta is suitable for selection of resistant calli; The transformation parameters of 100μg gold powder absorbing 0.2μg DNA per shot and 900 psi helium pressure and 6 cm bombardment distance and bombarded twice for each plate give the best result; Keeping the target calli on osmotic medium containing 60g/L mannitol from 12 ～24h before bombardment to 24～48h after it can increase the efficiencies of transformation . Furthermore, some transgenic indica rice plants are obtained using this optimized transformation system.展开更多
Major histocompatibility complex （MHC） genes are critical members in both innate and adaptive immunity, and the association between their polymorphism and disease resistance has been reported in many teleosts. In th...Major histocompatibility complex （MHC） genes are critical members in both innate and adaptive immunity, and the association between their polymorphism and disease resistance has been reported in many teleosts. In the present study, we first investigated the genetic variation at the MHC II β gene in orange-spotted grouper （Epinephelus coioides） after a challenge with Singapore grouper iridovirus （SGIV）. The results reveal that a high polymorphism level of the MHC II β gene （H = 1.000; K = 20.206; π=0.081） and at least three loci exist in grouper. The rate of dN/dS in the peptide-binding region （PBR） and non-PBR were both 〉1, suggesting the loci were evolving under positive selection. A high ratio of heterozygous individuals （37.26 %） and high rate of dN/dS were discovered, suggesting that both heterozygote advantage and frequency-dependent selection might result in the high polymorphism levels in MHC II β genes in grouper. A total of 33 MHC II β alleles were identified from 40 high-susceptibility （HS） and 40 high-re- sistance group （HR） individuals, and 15 alleles were used in the association analysis. Three alleles, EPCO-DBB＊0302, EPCO-DBB＊0307, EPCO-DBB＊0603, and EPCO- DBB＊1001 were significantly associated with resistance ability to SG1V, and the EPCO-DBB＊0607 and EPCO-DBB＊1303 alleles were associated with susceptibility （P 〈 0.05）. To further confirm the association, another independent challenge experiment was performed. The result of association analysis in the verification test found that only EPCO-DBB＊1001 alleles were significantly asso- ciated with resistance to SGIV （P 〈 0.05）, while the other alleles showed no significance （P 〉 0.05） in the frequency distribution between HR and HS groups. Therefore, the EPCO-DBB＊ 1001 alleles could be used as a disease resis- tance-related MHC marker in the molecular marker-assisted selective breeding program of grouper.展开更多
文摘Shoot-tip culture of strawberry is the most important way to get virus-free plants.Moreover,detoxification and rapid propagation are the key techniques for producing high-quality seeds and seedlings massively and rapidly and achieving the high-quality,high-yield and high-efficiency development of strawberry industry.We have recently produced virus-free strawberry seedlings by combing tissue culture technology and stolon-reproduction method and this technology has been widely used.In addition,a relatively perfect three breeding system of virus-free strawberry seedlings was established after production practices,guaranteeing the supply of high-quality seeds and seedlings and technical support for strawberry industry in corps.
基金the Chinese 863 High-Technology Program(NO.863-101-01-01-01)and Chinese Post-Doctoral Science Foundation(2001-14)
文摘In order to improve the frequency of indica rice transformation by biolistic bombardment, suitable culture conditions for embryonic calli,an optimal selection scheme for resistant calli and seedlings, and optimum bombardment parameters a investigated by using 14 commercially important indica rice cultivars. The main results show that the CC medium with 36g/L mannitol is a scheme subculture medium in which the browning of indica rice calli can be mitigated significantly; The concentration of 30～40mg/L Hyg or 150～200mg/L G418 or 10～20 mg/L Basta is suitable for selection of resistant calli; The transformation parameters of 100μg gold powder absorbing 0.2μg DNA per shot and 900 psi helium pressure and 6 cm bombardment distance and bombarded twice for each plate give the best result; Keeping the target calli on osmotic medium containing 60g/L mannitol from 12 ～24h before bombardment to 24～48h after it can increase the efficiencies of transformation . Furthermore, some transgenic indica rice plants are obtained using this optimized transformation system.
基金supported by China Postdoctoral Science Foundation Funded Project(2015M572380)National Basic Research Program of China(973)(2012CB114402)
文摘Major histocompatibility complex （MHC） genes are critical members in both innate and adaptive immunity, and the association between their polymorphism and disease resistance has been reported in many teleosts. In the present study, we first investigated the genetic variation at the MHC II β gene in orange-spotted grouper （Epinephelus coioides） after a challenge with Singapore grouper iridovirus （SGIV）. The results reveal that a high polymorphism level of the MHC II β gene （H = 1.000; K = 20.206; π=0.081） and at least three loci exist in grouper. The rate of dN/dS in the peptide-binding region （PBR） and non-PBR were both 〉1, suggesting the loci were evolving under positive selection. A high ratio of heterozygous individuals （37.26 %） and high rate of dN/dS were discovered, suggesting that both heterozygote advantage and frequency-dependent selection might result in the high polymorphism levels in MHC II β genes in grouper. A total of 33 MHC II β alleles were identified from 40 high-susceptibility （HS） and 40 high-re- sistance group （HR） individuals, and 15 alleles were used in the association analysis. Three alleles, EPCO-DBB＊0302, EPCO-DBB＊0307, EPCO-DBB＊0603, and EPCO- DBB＊1001 were significantly associated with resistance ability to SG1V, and the EPCO-DBB＊0607 and EPCO-DBB＊1303 alleles were associated with susceptibility （P 〈 0.05）. To further confirm the association, another independent challenge experiment was performed. The result of association analysis in the verification test found that only EPCO-DBB＊1001 alleles were significantly asso- ciated with resistance to SGIV （P 〈 0.05）, while the other alleles showed no significance （P 〉 0.05） in the frequency distribution between HR and HS groups. Therefore, the EPCO-DBB＊ 1001 alleles could be used as a disease resis- tance-related MHC marker in the molecular marker-assisted selective breeding program of grouper.
