[ Objective] The genetic diversity of the local cultivated aromatic rice and non-aromatic rice in Yunnan Province were compared to provide further genetic resources for breeding practice. [Method] Genetic diversity of...[ Objective] The genetic diversity of the local cultivated aromatic rice and non-aromatic rice in Yunnan Province were compared to provide further genetic resources for breeding practice. [Method] Genetic diversity of 10 aromatic rice and 45 non-aromatic rice were analyzed by 64 SSR primers covered on 12 rice chromosomes. [ Result] Per locus 5.44 and 7.98 alleles in average were detected, ranging from 2 to 12 and from 2 to 17 in aromatic and non-aromatic rice, respectively. Average genetic multiplicity index（Hs） was 0.46 and 0.67 respectively. The average polymorphism information content （PIC） was 0.43 and 0.58 in aromatic and non-aromatic rice respectively. [ Conclusion] The results indicated that genetic diversity was higher in non-aromatic rice than in aromatic rice.展开更多
This research focused on the impact of mining on the permeability of key aquifuge （N2 laterite） that is widespread in the arid and semi-arid areas of northwestern China and is critical for preserving water resources...This research focused on the impact of mining on the permeability of key aquifuge （N2 laterite） that is widespread in the arid and semi-arid areas of northwestern China and is critical for preserving water resources. The impact of mining stress recovery on the permeability of cracked N2 laterite was assessed for parts of northwestern China that included the Jingle laterite and Baode laterite. The mineral compositions and swelling properties of the laterite at both locations were examined, and analytical results showed that the laterite contained abundant clay minerals. The Baode laterite exhibited higher expansibility than Jingle laterite. The triaxial creep permeability performance of laterite specimens with a prefabricated crack width of 1.0, 1.5, and 2.5 mm were tested. The results indicated that strain of cracked laterite all exhibited transient creep following each level of loading, and then unstable creep and stable creep. With the increase of loading, the transient creep deformation corresponding to each level of loading decreased, the unstable creep deformation produced by identical loading gradually and incrementally increased. The nonlinear power function equation was selected to fit creep grading curves which have high precision. The cracks within the laterite gradually closed with the stress recovery, and permeability gradually recovered. During the stress recovery, the narrower cracks exhibited a smaller change in permeability. However, for narrow cracks in mining soil, permeability recovered after mining stress when permeability was closer to initial permeability, and the Baode laterite showed greater recovery than that of the Jingle laterite.展开更多
基金Supported by the General Programs of the National Natural ScienceFoundation of China(30460019)Key Technologies R&D Program ofYunnan Province(2006NG34,2008C004Z)Cooperative Program Between Yunnan Academy of Agricultural Sciences (YAAS) and RDA of Korea~~
文摘[ Objective] The genetic diversity of the local cultivated aromatic rice and non-aromatic rice in Yunnan Province were compared to provide further genetic resources for breeding practice. [Method] Genetic diversity of 10 aromatic rice and 45 non-aromatic rice were analyzed by 64 SSR primers covered on 12 rice chromosomes. [ Result] Per locus 5.44 and 7.98 alleles in average were detected, ranging from 2 to 12 and from 2 to 17 in aromatic and non-aromatic rice, respectively. Average genetic multiplicity index（Hs） was 0.46 and 0.67 respectively. The average polymorphism information content （PIC） was 0.43 and 0.58 in aromatic and non-aromatic rice respectively. [ Conclusion] The results indicated that genetic diversity was higher in non-aromatic rice than in aromatic rice.
基金The study was jointly supported by the State Key Program of National Natural Science Foundation of China （Grant No. 41430643） and the National Key Basic Research Program of China （973 Program） （Grant No. 2015CB251601）.
文摘This research focused on the impact of mining on the permeability of key aquifuge （N2 laterite） that is widespread in the arid and semi-arid areas of northwestern China and is critical for preserving water resources. The impact of mining stress recovery on the permeability of cracked N2 laterite was assessed for parts of northwestern China that included the Jingle laterite and Baode laterite. The mineral compositions and swelling properties of the laterite at both locations were examined, and analytical results showed that the laterite contained abundant clay minerals. The Baode laterite exhibited higher expansibility than Jingle laterite. The triaxial creep permeability performance of laterite specimens with a prefabricated crack width of 1.0, 1.5, and 2.5 mm were tested. The results indicated that strain of cracked laterite all exhibited transient creep following each level of loading, and then unstable creep and stable creep. With the increase of loading, the transient creep deformation corresponding to each level of loading decreased, the unstable creep deformation produced by identical loading gradually and incrementally increased. The nonlinear power function equation was selected to fit creep grading curves which have high precision. The cracks within the laterite gradually closed with the stress recovery, and permeability gradually recovered. During the stress recovery, the narrower cracks exhibited a smaller change in permeability. However, for narrow cracks in mining soil, permeability recovered after mining stress when permeability was closer to initial permeability, and the Baode laterite showed greater recovery than that of the Jingle laterite.
