甘薯近缘野生种Ipomoea Littoralis全基因组Survey分析

Ipomoea littoralis是甘薯的近缘野生种之一,对其全基因组的研究可为甘薯种质资源的创新提供参考,同时为全基因组精细图谱的绘制打下基础。本研究通过二代高通量测序技术（Illumina Hiseq 2500）,测序深度约为60×,经过滤后得到22.45 G数据,结合生物信息学手段估算基因组大小、杂合率、重复序列和GC含量等基因组特征。预估基因组大小经修正后为676.27 Mb。K-mer分析结果得出I. littoralis基因组中重复序列所占比率为60.98%,杂合率为0.81%;初步组装结果,contigs N50为0.684 kb,总读长为0.538 Gb,scaffolds N50为12.09 kb,总读长为0.602 Gb;GC平均深度及含量分布出现分层现象。本研究首次报道I. littoralis的基因组特征信息,为进一步全基因组深度测序提供参考。     

Correlated effects of exotic pollen‐fertility restorer genes on agronomic and quality traits of hybrid rye

In CMS (cytoplasmic male sterility)‐based hybrid rye (Secale cereale L.) breeding, effective pollen‐fertility restoration is an essential prerequisite for achieving maximum grain yield on the one hand and for minimizing ergot (Claviceps purpurea) infestation on the other. Restorer genes for the CMS‐inducing ‘Pampa’ cytoplasm derived from landraces collected in Iran and Argentina are used by breeders for achieving this goal. Here, restorer genes from four germplasm sources (‘Altevogt 14160’, ‘IRAN III’, ‘Trenelense’ and ‘Pico Gentario’) were analysed by producing three‐way cross hybrids between an elite CMS single cross and pollinators with and without a given restorer gene. Materials were evaluated on large drilled plots for restorer index (RI), grain yield, plant height and other traits in six environments. In experiment 1, a restorer gene from ‘Altevogt 14160’ was used. Seven pairs of marker‐selected carrier and non‐carrier backcross lines served as pollinators. In experiment 2, the pollinators were 17 backcross line pairs from the other three germplasm sources. These lines were grouped as high (RI > 67%) and low restorers (RI < 30%), respectively, using testcrosses with a highly diagnostic CMS tester. Hybrids carrying an exotic restorer gene suffered from a significant grain yield reduction by 4.4% and 9.4% and were 9.3 and 4.8 cm taller in experiments 1 and 2, respectively. Thousand‐kernel weight was reduced, whereas quality traits were only slightly affected. For all traits, significant genetic variance existed among the testcrosses to the presence vs. absence of a given exotic restorer gene. This offers a chance for the breeder to reduce or ultimately overcome the presently observed performance reductions brought about by exotic restorer genes.     

甜瓜雄性不育系ms2田间表型性状分析

选取甜瓜雄性不育系ms2作为研究材料,以常见栽培品种为对照,进行田间表型性状调查,对果实性状、品质指标等进行差异性分析,并以各性状相关性分析结果为依据进行聚类分析。结果显示甜瓜雄性不育系ms2与栽培品种在表型上差异显著,遗传距离较远。试验结果鉴定了甜瓜雄性不育系ms2的潜力,为下一步以雄性不育系作为亲本进行杂交组合配置提供了参考,同时为甜瓜种质资源的创新提供依据。     

Recovery of fertility in quinestrol‐treated or diethylstilbestrol‐treated mice: Implications for rodent management

Fertility control is an alternative strategy to traditional culling for the management of rodent pests. Previous studies have demonstrated that quinestrol is a potential contraceptive for male rodents, but the recovery of fertility in quinestrol‐treated rodents has not been evaluated. This study used C57BL/6J mice to evaluate the recovery rate of male fertility after the administration of quinestrol. Diethylstilbestrol (DES), a non‐steroid estrogenic compound, was used for comparison. Different groups of mice were treated with 1 mg/kg quinestrol, 1 mg/kg DES, or castor oil separately for 7 days. These mice were then killed on days 8, 22 and 50 respectively. Our results indicated that the weight of epididymides and seminal vesicles decreased significantly on days 8 and 22 in quinestrol/DES‐treated mice, with extensive histological changes in the seminiferous tubules. Sperm concentrations in the cauda epididymal fluid were significantly reduced on days 8 and 22 in both quinestrol and DES treatment groups and on day 50 for the DES, but not the quinestrol group. Further analysis revealed that DES‐treated mice exhibited a higher proportion of abnormal sperm accumulation in the epididymis, indicating that the normal sperm transportation to the cauda epididymis was blocked. Our results indicate that the anti‐fertility effects on male mice given quinestrol were of shorter duration than for those receiving DES at the dose of 1 mg/kg body weight.     

K型不育系RS53A育性恢复研究及杂种优势分析

为了选育K型不育系的恢复系和配制优势组合，利用72个黄淮麦区优良小麦品种（系）与K型不育系配制测交组合，测定K型不育系的育性恢复性和杂种优势。结果表明，72个测交组合中，高可育和全可育共占比54.16%，说明K型不育系能被黄淮麦区大多数品种恢复育性，其中5个测交组合的国内法自交结实率均超过80%，表现全可育，其国际法自交结实率均超过100%，最高的组合达到158.33%；16个测交组合的国内法和国际法自交结实率均为0，表现全不育，对K型不育系进行回交转育，可培育新的不育系。利用24个测交组合进行超标优势分析，结果表明，8个农艺性状中，单穗粒数的平均超标优势最高，为9.23%，其次为穗长和千粒重，平均超标优势分别为5.80%和5.24%，且这3个性状的超标优势对产量的超标优势贡献最大，其中，3个测交组合的超标优势表现突出，具有增产潜力,可以进行下一步研究。     

利用雄性不育系及异型保持系配制萝卜三交种研究

萝卜(Raphanus sativus L.)三交种对萝卜杂交优势及组合力测定的研究目前在国内外还很少开展,试验以4套萝卜核质互作型雄性不育系及10个父本自交系为试验材料,配制三交种及单交种组合,比较了三交种与单交种在产量、生物学性状、抗逆性、抗病性及耐抽薹性方面的差异。3年的试验结果表明,大部分三交种较单交种有抗病、高产的表现,配制的9组试验组合中,6组三交种产量高于单交种,增幅在2.6%～52.5%;抗病性方面三交种普遍强于单交种;而耐抽薹性与亲本特性密切相关。     

红萝卜新品种"福娃1号"的选育

以不育系604A为母本,以03-91-562-1为父本配制而成的经济性状优良,符合市场需求的红萝卜新品种"福娃1号"。该品种中晚熟,生育期76d,株态半开张,开张度73.83cm;叶片长度44.7cm,叶片宽度19.43cm,主脉色泽红色,叶绿色,叶片阔倒卵形,肉质根扁圆形,皮色鲜红,肉白色,肉质根长度13.28cm,肉质根粗度16.6cm,表皮光滑。平均单株重1.83kg,肉质根重1.4kg。抗病性好,风味品质优,商品品质好,不易糠心,产量高,易于采收,栽培适应性强,适于辽宁省各地栽培。     

板栗‘遵玉’大小孢子发生及雌雄配子体发育研究

为了系统了解板栗雌雄花发育过程,以板栗优良品种‘遵玉’为试材,对大小孢子及雌雄配子体发生发育进行研究。结果表明:花药壁由外而内分别为表皮、药室内壁、中层及绒毡层(为腺质型),属于基本型。小孢子胞质分离为同时型,四分体为典型的四面体型,少数呈左右对称排列。雄配子体只经过1次有丝分裂,花粉成熟为2-细胞型。雌花胚囊发育为蓼型胚囊,只有1个胚囊母细胞发育成胚囊,四分体呈线性排列,整个发育过程与雌雄花外部特征密切相关。确定观察减数分裂最佳取样时期为:雄花花序长度为10~17 cm,总苞直径为0.9~1.6 cm。‘遵玉’小孢子及雄配子体发生发育不存在异常表现,表明‘遵玉’雄配子体发育正常,花粉可育,可以作为授粉树。     

H2A变体在小鼠不同时期雄性生殖细胞核质区的分布

【目的】了解小鼠雄性生殖细胞中macro H2A、H2A.Z和H2A.X 3种组蛋白变体变化与其发育特征间的联系,为揭示原始生殖细胞（PGCs）的发育机理及其分子调控机制奠定基础。【方法】以C57BL/6J小鼠胚胎的中肾和生殖嵴为试验材料,通过免疫荧光染色技术检测11.5dpc、12.5dpc和13.5dpc不同发育时期含有PGCs的组织石蜡切片及单细胞中macro H2A、H2A.X和H2A.Z变体的分布情况。【结果】macro H2A变体在11.5dpc胚胎时主要存在于细胞质中,12.5dpc时在细胞质中的表达增强,但进入生殖嵴后（13.5dpc）表达消失;H2A.X变体在11.5dpc和12.5dpc时存在于PGCs的核质区,13.5dpc时主要存于细胞质,且呈聚集分布;H2A.Z变体在11.5dpc时在PGCs的核质区均有存在,12.5dpc和13.5dpc时主要分布在细胞核,且表达明显增强。【结论】随着PGCs的不断迁移、增殖与分化,macro H2A、H2A.X和H2A.Z 3种组蛋白H2A变体在细胞核质区的分布及表达情况也发生变化,即H2A变体分布特征与PGCs的性别分化及其有丝分裂停止相关。