Take-all is a devastating soil-borne disease of wheat(Triticum aestivum L.).Cultivating resistant line is an important measure to control this disease.Psathyrostachys huashanica Keng is a valuable germplasm resource w...Take-all is a devastating soil-borne disease of wheat(Triticum aestivum L.).Cultivating resistant line is an important measure to control this disease.Psathyrostachys huashanica Keng is a valuable germplasm resource with high resistance to take-all.This study reported on a wheat-/R huashanica introgression line H148 with improved take-all resistance compared with its susceptible parent 7182.To elucidate the genetic mechanism of resistance in H148,the F_(2)genetic segregating population of H148×XN585 was constructed.The mixed genetic model analysis showed that the take-all resistance was controlled by two major genes with additive,dominant and epistasis effects.Bulked segregant analysis combined with wheat axiom 660K genotyping array analysis showed the polymorphic SNPs with take-all resistance from P.huashanica alien introgression were mainly distributed on the chromosome 2A.Genotyping of the F_(2)population using the KASP marker mapped a major QTL in an interval of 68.8-70.1 Mb on 2AS.Sixty-two genes were found in the target interval of the Chinese Spring reference genome sequence.According to the functional annotation of genes,two protein genes that can improve the systematic resistance of plant roots were predicted as candidate genes.The development of wheat-P.huashanica introgression line H148 and the resistant QTL mapping information are expected to provide some valuable references for the fine mapping of disease-resistance gene and development of take-all resistant varieties through molecular marker-assisted selection.展开更多
A quantum well intermixing（QW1） investigation on double quantum well（DQW） structure with two different emitting wavelength caused by phosphorus ion implantation and following rapid thermal annealing （RTA） was ca...A quantum well intermixing（QW1） investigation on double quantum well（DQW） structure with two different emitting wavelength caused by phosphorus ion implantation and following rapid thermal annealing （RTA） was carried out by means of photoluminescence（PL）. The ion implantation was performed at the energy of 120 keV with the dose ranging from 1 × 10^11cm^-2 to 1× 10^14cm^-2. The RTA was performed at the temperature of 700 ℃ for 30 s under pure nitrogen protection. The PL measurement implied that the band gap blue-shift from the upper well increases with the ion dose faster than that from lower well and the PL peaks from both QWs remained well separated under the lower dose implantation（-1 × 10^11cm^-2） indicating that the implant vacancy distribution affects the QWl. When the ion dose is over - 1 × 10^12cm^-2, the band gap blue-shift from both wells increases with the ion dose and finally the two peaks merge together as one peak indicating the ion implantation caused a total intermixing of both quantum wells.展开更多
Bandgap tuning of the InGaAsP/InP multiple quantum well(MQW)laser structure by the impurity-free vacancy diffusion(IFVD)is investigated using photoluminescence.It has been demonstrated that the effects of the plasma b...Bandgap tuning of the InGaAsP/InP multiple quantum well(MQW)laser structure by the impurity-free vacancy diffusion(IFVD)is investigated using photoluminescence.It has been demonstrated that the effects of the plasma bombardment to the sample surface involved in the IFVD technique can enhance the intermixing of the InGaAsP/InP MQW laser structure.The reliability of the IFVD technique,particularly the effects of the surface decomposition and the intrinsic defects formed in the growth or preparation of the wafer,has been discussed.展开更多
基金the National Natural Science Foundation of China(31571650 and 31771785)the National Key Research and Development Program of China(2017YFD0100701)+1 种基金the Key Projects in Shaanxi Provincial Agricultural Field,China(2018ZDXM-NY-006)the Key Research and Development Project of Shaanxi Province,China(2019ZDLNY04-05).
文摘Take-all is a devastating soil-borne disease of wheat(Triticum aestivum L.).Cultivating resistant line is an important measure to control this disease.Psathyrostachys huashanica Keng is a valuable germplasm resource with high resistance to take-all.This study reported on a wheat-/R huashanica introgression line H148 with improved take-all resistance compared with its susceptible parent 7182.To elucidate the genetic mechanism of resistance in H148,the F_(2)genetic segregating population of H148×XN585 was constructed.The mixed genetic model analysis showed that the take-all resistance was controlled by two major genes with additive,dominant and epistasis effects.Bulked segregant analysis combined with wheat axiom 660K genotyping array analysis showed the polymorphic SNPs with take-all resistance from P.huashanica alien introgression were mainly distributed on the chromosome 2A.Genotyping of the F_(2)population using the KASP marker mapped a major QTL in an interval of 68.8-70.1 Mb on 2AS.Sixty-two genes were found in the target interval of the Chinese Spring reference genome sequence.According to the functional annotation of genes,two protein genes that can improve the systematic resistance of plant roots were predicted as candidate genes.The development of wheat-P.huashanica introgression line H148 and the resistant QTL mapping information are expected to provide some valuable references for the fine mapping of disease-resistance gene and development of take-all resistant varieties through molecular marker-assisted selection.
文摘A quantum well intermixing（QW1） investigation on double quantum well（DQW） structure with two different emitting wavelength caused by phosphorus ion implantation and following rapid thermal annealing （RTA） was carried out by means of photoluminescence（PL）. The ion implantation was performed at the energy of 120 keV with the dose ranging from 1 × 10^11cm^-2 to 1× 10^14cm^-2. The RTA was performed at the temperature of 700 ℃ for 30 s under pure nitrogen protection. The PL measurement implied that the band gap blue-shift from the upper well increases with the ion dose faster than that from lower well and the PL peaks from both QWs remained well separated under the lower dose implantation（-1 × 10^11cm^-2） indicating that the implant vacancy distribution affects the QWl. When the ion dose is over - 1 × 10^12cm^-2, the band gap blue-shift from both wells increases with the ion dose and finally the two peaks merge together as one peak indicating the ion implantation caused a total intermixing of both quantum wells.
基金Supported by the National Natural Science Foundation of China under Grant No.69786001“New Star”program for science and technology in Beijing(Contract No.952870300).
文摘Bandgap tuning of the InGaAsP/InP multiple quantum well(MQW)laser structure by the impurity-free vacancy diffusion(IFVD)is investigated using photoluminescence.It has been demonstrated that the effects of the plasma bombardment to the sample surface involved in the IFVD technique can enhance the intermixing of the InGaAsP/InP MQW laser structure.The reliability of the IFVD technique,particularly the effects of the surface decomposition and the intrinsic defects formed in the growth or preparation of the wafer,has been discussed.
