Background: The aim of this study was to estimate variance components and to identify genomic regions and pathways associated with resistance to gastrointestinal parasites, particularly Haemonchus contortus, in a bre...Background: The aim of this study was to estimate variance components and to identify genomic regions and pathways associated with resistance to gastrointestinal parasites, particularly Haemonchus contortus, in a breed of sheep adapted to tropical climate. Phenotypes evaluations were performed to verify resistance to gastrointestinal parasites, and were divided into two categories: i) farm phenotypes, assessing body condition score(BCS), degree of anemia assessed by the famacha chart(FAM), fur score(FS) and feces consistency(FC); and ii) lab phenotypes,comprising blood analyses for hematocrit(HCT), white blood cell count(WBC), red blood cell count(RBC),hemoglobin(HGB), platelets(PLT) and transformed(log10) egg per gram of feces(EPG_(log)). A total of 576 animals were genotyped with the Ovine SNP12k Bead Chip(Illumina, Inc.), that contains 12,785 bialleleic SNP markers. The variance components were estimated using a single trait model by single step genomic BLUP procedure.Results: The overall linkage disequilibrium(LD) mean between pairs of markers measured by r2 was 0.23. The overall LD mean between markers considering windows up to 10 Mb was 0.07. The mean LD between adjacent SNPs across autosomes ranged from 0.02 to 0.10. Heritability estimates were low for EPG_(log)(0.11), moderate for RBC(0.18), PLT(0.17) HCT(0.20), HGB(0.16) and WBC(0.22), and high for FAM(0.35). A total of 22, 21, 23, 20, 26, 25 and 23 windows for EPG_(log)for FAM, WBC, RBC, PLT, HCT and HGB traits were identified, respectively. Among the associated windows, 10 were shown to be common to HCT and HGB traits on OAR1, OAR2, OAR3, OAR5, OAR8 and OAR15.Conclusion: The traits indicating gastrointestinal parasites resistance presented an adequate genetic variability to respond to selection in Santa Inês breed, and it is expected a higher genetic gain for FAM trait when compared to the others. The level of LD estimated for markers separated by less than 1 Mb indicated that the Ovine SNP12k Bead Chip might be a suitable tool for identifying genomic regions associated with traits related to gastrointestinal parasite resistance. Several candidate genes related to immune system development and activation, inflammatory response,regulation of lymphocytes and leukocytes proliferation were found. These genes may help in the selection of animals with higher resistance to parasites.展开更多
In order to reduce the use of peat resources and realize the sustainable development of tobacco, the pH of distiller s grain substrate was adjusted with humic acid, and the effects of various distiller s grain substra...In order to reduce the use of peat resources and realize the sustainable development of tobacco, the pH of distiller s grain substrate was adjusted with humic acid, and the effects of various distiller s grain substrates on the growth of tobacco seedlings were studied to find out the method of cultivating high-quality tobacco seedlings by using distiller s grain substrate. The results showed that when 60% of humic acid was added to the distiller s grain substrate made from coarse distiller s grains, fine distiller s grains, perlite and vermiculite, both the pH and electrical conductivity decreased significantly and were similar to that of the conventional substrate. Moreover, the emergence rate of tobacco seedlings, the rate of strong tobacco seedlings, leaf number, stem height, root growth and quality of tobacco seedlings were good.展开更多
The genetic and breeding progress of Dahen S06M line was analyzed, in order to improve the selection efficiency. The results showedthat six generations of selection was effective in selecting main characters of S06M l...The genetic and breeding progress of Dahen S06M line was analyzed, in order to improve the selection efficiency. The results showedthat six generations of selection was effective in selecting main characters of S06M line, especially the selection of growth rate had no adverse effecton reproductive performance. All indicators of reproductive performance were improved in varying degrees during breeding, particularly the egg production at 68 weeks of age. The breeding progress of main target traits significantly slowed down after the second generation, but they still maintained at higher levels and the characters of S06M tended to be stable.展开更多
虬S是福建省农业科学院水稻研究所以P88S为母本与常规稻广东三抗为父本杂交,通过福建沙县与海南三亚两地穿梭,经6 a 12代的定向培育成的籼型水稻温敏核不育系,具有米质优、外露率高、抗稻瘟、繁制种产量高等特点,2020年通过福建省农作...虬S是福建省农业科学院水稻研究所以P88S为母本与常规稻广东三抗为父本杂交,通过福建沙县与海南三亚两地穿梭,经6 a 12代的定向培育成的籼型水稻温敏核不育系,具有米质优、外露率高、抗稻瘟、繁制种产量高等特点,2020年通过福建省农作物品种审定委员会审定。展开更多
During the China’"Eighth Five-year Plan", the Chinese rice breeders developed hundreds of new rice varieties(combinations) which have higher yield, better rice quality or higher resistance. Among them, 83 n...During the China’"Eighth Five-year Plan", the Chinese rice breeders developed hundreds of new rice varieties(combinations) which have higher yield, better rice quality or higher resistance. Among them, 83 new varieties (combinations) were released in the national or provincial levels. In addition, many new germplasms and excellence breeding materials were obtained which is rery useful for the rice breeding in the future.展开更多
If you didn't know by now, Santa has a soft spot for China. From early November, the plastic cut outs of his rosy cheeks,piercing blue eyes and frothy beard watch you from every doorway, window and shop front. Some h...If you didn't know by now, Santa has a soft spot for China. From early November, the plastic cut outs of his rosy cheeks,piercing blue eyes and frothy beard watch you from every doorway, window and shop front. Some have even remained posted from the previous year. Christmas decorations become the most competitive game in town, with no self-respecting business wanting to be left behind breathing in tinsel dust.展开更多
基金Sao Paulo Research Foundation–FAPESP grants#2010/05516–7,#2011/00396–6 and#2014/07566–2
文摘Background: The aim of this study was to estimate variance components and to identify genomic regions and pathways associated with resistance to gastrointestinal parasites, particularly Haemonchus contortus, in a breed of sheep adapted to tropical climate. Phenotypes evaluations were performed to verify resistance to gastrointestinal parasites, and were divided into two categories: i) farm phenotypes, assessing body condition score(BCS), degree of anemia assessed by the famacha chart(FAM), fur score(FS) and feces consistency(FC); and ii) lab phenotypes,comprising blood analyses for hematocrit(HCT), white blood cell count(WBC), red blood cell count(RBC),hemoglobin(HGB), platelets(PLT) and transformed(log10) egg per gram of feces(EPG_(log)). A total of 576 animals were genotyped with the Ovine SNP12k Bead Chip(Illumina, Inc.), that contains 12,785 bialleleic SNP markers. The variance components were estimated using a single trait model by single step genomic BLUP procedure.Results: The overall linkage disequilibrium(LD) mean between pairs of markers measured by r2 was 0.23. The overall LD mean between markers considering windows up to 10 Mb was 0.07. The mean LD between adjacent SNPs across autosomes ranged from 0.02 to 0.10. Heritability estimates were low for EPG_(log)(0.11), moderate for RBC(0.18), PLT(0.17) HCT(0.20), HGB(0.16) and WBC(0.22), and high for FAM(0.35). A total of 22, 21, 23, 20, 26, 25 and 23 windows for EPG_(log)for FAM, WBC, RBC, PLT, HCT and HGB traits were identified, respectively. Among the associated windows, 10 were shown to be common to HCT and HGB traits on OAR1, OAR2, OAR3, OAR5, OAR8 and OAR15.Conclusion: The traits indicating gastrointestinal parasites resistance presented an adequate genetic variability to respond to selection in Santa Inês breed, and it is expected a higher genetic gain for FAM trait when compared to the others. The level of LD estimated for markers separated by less than 1 Mb indicated that the Ovine SNP12k Bead Chip might be a suitable tool for identifying genomic regions associated with traits related to gastrointestinal parasite resistance. Several candidate genes related to immune system development and activation, inflammatory response,regulation of lymphocytes and leukocytes proliferation were found. These genes may help in the selection of animals with higher resistance to parasites.
基金Supported by the Project of Luzhou Company of Sichuan Provincial Tobacco Company"Comprehensive Application of Distillers'Grains on Tobacco"
文摘In order to reduce the use of peat resources and realize the sustainable development of tobacco, the pH of distiller s grain substrate was adjusted with humic acid, and the effects of various distiller s grain substrates on the growth of tobacco seedlings were studied to find out the method of cultivating high-quality tobacco seedlings by using distiller s grain substrate. The results showed that when 60% of humic acid was added to the distiller s grain substrate made from coarse distiller s grains, fine distiller s grains, perlite and vermiculite, both the pH and electrical conductivity decreased significantly and were similar to that of the conventional substrate. Moreover, the emergence rate of tobacco seedlings, the rate of strong tobacco seedlings, leaf number, stem height, root growth and quality of tobacco seedlings were good.
基金Supported by 13~(th) Five-year Broiler Breeding Project of Sichuan Province(2016NYZ0025,2016NY20043)
文摘The genetic and breeding progress of Dahen S06M line was analyzed, in order to improve the selection efficiency. The results showedthat six generations of selection was effective in selecting main characters of S06M line, especially the selection of growth rate had no adverse effecton reproductive performance. All indicators of reproductive performance were improved in varying degrees during breeding, particularly the egg production at 68 weeks of age. The breeding progress of main target traits significantly slowed down after the second generation, but they still maintained at higher levels and the characters of S06M tended to be stable.
文摘During the China’"Eighth Five-year Plan", the Chinese rice breeders developed hundreds of new rice varieties(combinations) which have higher yield, better rice quality or higher resistance. Among them, 83 new varieties (combinations) were released in the national or provincial levels. In addition, many new germplasms and excellence breeding materials were obtained which is rery useful for the rice breeding in the future.
文摘If you didn't know by now, Santa has a soft spot for China. From early November, the plastic cut outs of his rosy cheeks,piercing blue eyes and frothy beard watch you from every doorway, window and shop front. Some have even remained posted from the previous year. Christmas decorations become the most competitive game in town, with no self-respecting business wanting to be left behind breathing in tinsel dust.