The embryogenic callus induction and shoot regeneration were studied systematically in elite clone GL9 of Eucalyptus cultivated widely in south China.We investigated TDZ 0.02-0.05 mg·L-1 was the proper concentrat...The embryogenic callus induction and shoot regeneration were studied systematically in elite clone GL9 of Eucalyptus cultivated widely in south China.We investigated TDZ 0.02-0.05 mg·L-1 was the proper concentration.The callus induction rate was 92.9%—100%.When TDZ concentration was higher than 0.1 mg·L-1,the axillary bud germination was completely inhibited.TDZ 0.02 mg·L-1 with combinations of CoCl2 0.125 mg·L-1 could induct the embryogenic callus.The direct regeneration rate was 13.39%±1.03%,and with combinations of NAA 0.1mg·L-1 could not differentiate directly from callus,but higher regeneration rate(20.2%±13.3%) could be obtained by transferring callus onto regeneration medium.The size of callus can increase to 1.4 fold of its original size in the first subculture in modified MS+TDZ 0.02 mg·L-1 +NAA 0.1 mg·L-1medium and the average number of deep-pink-coloured masses of embryogenic cells on each callus was 8.4.In the second and third subculture,callus stopped growing further and the number of masses of embryogenic cells decreased gradually.Regeneration system could lay a good foundation for further transformation research.展开更多
Grain size is a key factor influencing grain yield and appearance quality in rice.We identified twelve quantitative trait loci(QTL)for grain length(GL),nine for grain width(GW),and nine for 1000-kernel weight(TKW)usin...Grain size is a key factor influencing grain yield and appearance quality in rice.We identified twelve quantitative trait loci(QTL)for grain length(GL),nine for grain width(GW),and nine for 1000-kernel weight(TKW)using GLU-SSSLs,which are single-segment substitution lines with Oryza glumaepatula as donor parent and Huajingxian 74(HJX74)as recipient parent.Among the QTL,qGL1-2,qGL1-4,qGL9-2,qGW2-2,qGW9-1 and qTKW9-2 contributed to high grain yield.GL9 was identified as a candidate gene for qGL9-2 by map-based cloning and sequencing,and is a novel allele of GS9.The kernel of NIL-gl9was slenderer and longer than that of HJX74,and the TKW and grain yield per plant of NIL-gl9 were higher than those of HJX74.The proportion of grain chalkiness of NIL-gl9 was much lower than that of HJX74.Thus,gl9 increased grain yield and appearance quality simultaneously.Three pyramid lines,NIL-gs3/gl9,NIL-GW7/gl9 and NIL-gw8/gl9,were developed and the kernel of each was longer than that of the corresponding recipient parent lines.The gl9 allele may be beneficial for breeding rice varieties with high grain yield and good appearance quality.展开更多
文摘The embryogenic callus induction and shoot regeneration were studied systematically in elite clone GL9 of Eucalyptus cultivated widely in south China.We investigated TDZ 0.02-0.05 mg·L-1 was the proper concentration.The callus induction rate was 92.9%—100%.When TDZ concentration was higher than 0.1 mg·L-1,the axillary bud germination was completely inhibited.TDZ 0.02 mg·L-1 with combinations of CoCl2 0.125 mg·L-1 could induct the embryogenic callus.The direct regeneration rate was 13.39%±1.03%,and with combinations of NAA 0.1mg·L-1 could not differentiate directly from callus,but higher regeneration rate(20.2%±13.3%) could be obtained by transferring callus onto regeneration medium.The size of callus can increase to 1.4 fold of its original size in the first subculture in modified MS+TDZ 0.02 mg·L-1 +NAA 0.1 mg·L-1medium and the average number of deep-pink-coloured masses of embryogenic cells on each callus was 8.4.In the second and third subculture,callus stopped growing further and the number of masses of embryogenic cells decreased gradually.Regeneration system could lay a good foundation for further transformation research.
基金supported by the major science and technology research projects of Guangdong Laboratory for Lingnan Modern Agriculture(NT2021001)the Key Projects of Basic Research and Applied Basic Research of Guangdong Province(2019B030302006)+1 种基金the National Natural Science Foundation of China(32072040,31622041)the National Innovation and Entrepreneurship Training Program for College Students(202110564045)。
文摘Grain size is a key factor influencing grain yield and appearance quality in rice.We identified twelve quantitative trait loci(QTL)for grain length(GL),nine for grain width(GW),and nine for 1000-kernel weight(TKW)using GLU-SSSLs,which are single-segment substitution lines with Oryza glumaepatula as donor parent and Huajingxian 74(HJX74)as recipient parent.Among the QTL,qGL1-2,qGL1-4,qGL9-2,qGW2-2,qGW9-1 and qTKW9-2 contributed to high grain yield.GL9 was identified as a candidate gene for qGL9-2 by map-based cloning and sequencing,and is a novel allele of GS9.The kernel of NIL-gl9was slenderer and longer than that of HJX74,and the TKW and grain yield per plant of NIL-gl9 were higher than those of HJX74.The proportion of grain chalkiness of NIL-gl9 was much lower than that of HJX74.Thus,gl9 increased grain yield and appearance quality simultaneously.Three pyramid lines,NIL-gs3/gl9,NIL-GW7/gl9 and NIL-gw8/gl9,were developed and the kernel of each was longer than that of the corresponding recipient parent lines.The gl9 allele may be beneficial for breeding rice varieties with high grain yield and good appearance quality.