地方小麦品种贵协3号赤霉病抗性QTL的定位与效应鉴定

为明确抗填料霉病地方小麦品种贵协3号的赤霉病抗性遗传基础,利用感赤霉病品种绵麦96-5及其构建的含有196个株系的双单倍体(doubled haploid,DH)群体为材料,于2018和2019年分别在江苏南京和四川绵阳对赤霉病严重度进行调查,并利用55K DArT基因芯片技术构建的遗传图谱进行QTL定位。结果表明,所构建的遗传图谱覆盖小麦全基因组,图谱全长15195.8 cM,平均图距10.6 cM。利用复合区间作图法共检测到3个抗赤霉病QTL(QTL-FHB.GX-2B、QTL-FHB.GX-5B和QTL-FHB.GX-7A),分布在2B、5B和7A染色体上,抗性等位基因均来自于抗病亲本贵协3号,可解释1.2%~1.5%的表型变异,说明贵协3号的赤霉病抗性是多个微效基因/QTLs的累加效应。

Study of time-domain digital pulse shaping algorithms for nuclear signals

With the development on high-speed integrated circuit,fast high resolution sampling ADC and digital signal processors are replacing analog shaping amplifier circuit.This paper firstly presents the numerical analysis and simulation on R-C shaping circuit model and C-R shaping circuit model.Mathematic models are established based on 1st order digital differential method and Kirchhoff Current Law in time domain,and a simulation and error evaluation experiment on an ideal digital signal are carried out with Excel VBA.A digital shaping test for a semiconductor X-ray detector in real time is also presented.Then a numerical analysis for Sallen-Key(S-K) low-pass filter circuit model is implemented based on the analysis of digital R-C and digital C-R shaping methods.By applying the 2nd order non-homogeneous differential equation,the authors implement a digital Gaussian filter model for a standard exponential-decaying signal and a nuclear pulse signal.Finally,computer simulations and experimental tests are carried out and the results show the possibility of the digital pulse processing algorithms.

153份四川小麦主推品种和后备品系抗病基因的分子检测

为了解四川现有主栽小麦品种的抗病现状,发现并推广多抗性小麦品种,选用四川省153份小麦主要推广品种和后备品系,采用条锈菌接种诱发鉴定的方法于2018—2019和2019—2020年度进行条锈病成株期抗性鉴定与分析,同时利用已知抗病基因Yr5、Yr9、Yr10、Yr15、Yr18、Yr26、Pm21和Fhb1的分子标记分别对其进行抗条锈病、赤霉病和白粉病基因检测。结果显示,在153份供试小麦材料的条锈病成株期抗性鉴定中,两年度均表现为抗病的材料有122份,占供试材料的79.7%。分子标记检测结果表明,可能携带抗条锈病基因Yr5、Yr9、Yr10、Yr15、Yr18和Yr26的小麦材料分别有12、25、77、12、4和90份,分别占供试材料的7.8%、16.3%、50.3%、7.8%、2.6%和58.8%;可能携带抗白粉病基因Pm21的小麦材料有40份,占供试材料的26.1%;可能携带抗赤霉病基因Fhb1的小麦材料有12份,占供试材料的7.8%;有15份抗病材料未检测到本研究所测基因。

Evaluation of Wheat Stripe Rust Resistance in Sichuan Province

Wheat stripe rust,caused by Puccinia striiformis Westend. f. sp. tritici Erikss.（ Pst）,is one of the most destructive diseases of wheat（ Triticum aestivum L.） worldwide. Sichuan province plays an important role in stripe rust epidemic in China. To identify and evaluate wheat stripe rust resistance in Sichuan Province,134 wheat cultivars（ lines） were inoculated with seven Pst races at seedling stage and adult stage. The results indicated that the resistance frequencies of wheat cultivars（ lines） against seven races CYR31,Su11-7,CYR29,Su11-4,CYR32,CYR33 and V26 were 92. 4%,92. 5%,89. 3%,89. 4%,87. 3%,85. 0% and 82. 8%,respectively. Among 134 materials,76（ 56. 0%） performed resistance against all tested races both in seedling and adult stages. The virulence of new pathogenic type V26 of Pst on wheat cultivars（ lines） was stronger than the dominant races CYR32 and CYR33. All wheat cultivars（ lines） were classified into three types according to analysis of resistance spectrum; 66. 4% of cultivars（ lines） showed all-stage resistance,17. 9% were adult-plant resistance,and 15. 7% were susceptible. This indicated that although the overall resistance level of wheat cultivars（ lines） in Sichuan Province was very high,the resistance type was simple. Therefore,it is important to identify new resistance genes and enhance resistance gene diversity. Meanwhile,pyramiding breeding of all-stage resistance gene and adult-plant resistance gene could be gradually developed,to achieve durable resistance of wheat cultivars（lines） against stripe rust in Sichuan Province.

基于SLC7A11/GSH/GPX4信号轴的姜黄素诱导结直肠癌SW620细胞铁死亡的研究

目的:基于溶负荷转运体家族7成员11(SLC7A11)/谷胱甘肽(GSH)/谷胱甘肽过氧化物酶4(GPX4)信号轴研究姜黄素抑制人结直肠癌SW620细胞增殖和诱导铁死亡的作用机制。方法:MTT法检测姜黄素对SW620细胞增殖的影响;克隆形成试验研究姜黄素对SW620细胞克隆形成能力的影响;透射电子显微镜观察姜黄素对SW620细胞铁死亡形态的影响;荧光探针法检测姜黄素对SW620细胞内Fe^(2+)和脂质过氧化物水平的影响;试剂盒检测姜黄素对SW620细胞内MDA含量和GSH/GSSG比值的影响;qRT-PCR法检测姜黄素对SW620细胞铁死亡相关mRNA表达的影响;Western blot法检测姜黄素对SW620细胞铁死亡相关蛋白表达的影响。结果:与模型对照组比较,姜黄素能有效地抑制人结直肠癌SW620细胞的增殖。姜黄素20μmol/L处理后,SW620细胞线粒体呈现铁死亡典型形态,并且姜黄素能够升高SW620细胞内MDA、Fe^(2+)和脂质过氧化物的含量,降低GSH/GSSG比值(P<0.01),提示姜黄素能够诱导SW620细胞铁死亡;与模型对照组比较,姜黄素20、40μmol/L组均能够明显上调SW620细胞P53 mRNA和蛋白表达(P<0.05或P<0.01),同时显著下调Slc7a11、Gpx4 mRNA和蛋白表达(P<0.05或P<0.01),从而诱导结直肠癌细胞铁死亡。结论:姜黄素具有抗结直肠癌的作用,并通过抑制SLC7A11/GSH/GPX4信号轴,诱导结直肠癌细胞铁死亡。

Unfolding the fast neutron spectra of a BC501A liquid scintillation detector using GRAVEL method

Accurate knowledge of the neutron energy spectra is useful in basic research and applications. The overall procedure of measuring and unfolding the fast neutron energy spectra with BC501 A liquid scintillation detector is described. The recoil proton spectrum of 241Am-Be neutrons was obtained experimentally. With the NRESP7 code, the response matrix of detector was simulated.Combining the recoil proton spectrum and response matrix, the unfolding of neutron spectra was performed by GRAVEL iterative algorithm. A MatLab program based on the GRAVEL method was developed. The continuous neutron spectrum of 241Am-Be source and monoenergetic neutron spectrum of D-T source have been unfolded successfully and are in good agreement with their standard reference spectra. The unfolded 241Am-Be spectrum are more accurate than the spectra unfolded by artificial neural networks in recent years.

CIMMYT小麦材料Kundan条锈病成株抗性QTL的定位与效应鉴定

小麦条锈病是严重影响中国小麦产量的主要病害之一,利用成株抗性是小麦抗病育种的重要方向。本研究利用国际玉米小麦改良中心(centro internacional de mejoramientode maizy trigo,CIMMYT)引进的条锈病成株抗性品种Kundan和易感品种Avocet构建而成的131株群体大小的重组自交系群体来研究小麦条锈病成株抗性遗传基础。通过小麦50K DArT-Seq基因芯片技术完成131重组自交系群体的基因分型,经筛选获得了1 293个DArT-Seq标记,构建了分布于21条染色体上的22个连锁群,总长度为1 715.934 cM,两标记间的平均距离为1.34 cM。A、B和D基因连锁群长度分别为809.379 cM、674.469 cM和232.086 cM。连续两年在四川绵阳调查成株期抗性表型鉴定,利用复合区间作图法鉴定出一个位于染色体1BL上的抗条锈病主效基因QTL,位于标记G1107928与G1121552之间,遗传距离为5.5 cM,解释表型变异14.8%~18.8%,发现该基因不同于1BL上其他抗条锈病基因,具有成株抗性,为该基因的分子辅助选择和遗传利用提供了依据。