苦瓜叶片叶绿素含量的遗传分析

为探究苦瓜叶片叶绿素含量遗传特点,加快高产优质新品种选育进程,以苦瓜高代自交系$\otimes$04-17-6和$\otimes$25-6配组产生的6个世代P₁、P₂、F₁、B₁、B₂和F₂为材料,利用主基因+多基因混合遗传模型和ABC尺度测验2种方法,对苦瓜叶片叶绿素含量进行遗传分析。主基因+多基因混合遗传模型分析结果表明,叶绿素含量遗传受1对加性-显性主基因+加性-显性-上位性多基因控制,且高叶绿素含量对低叶绿素含量为不完全显性。3个分离世代B₁、B₂、F₂的主基因遗传率分别为2.86%、75.35%、79.79%,多基因遗传率分别为87.81%、0%、0%,环境变异为9.33%~24.65%,主基因的加性效应d_a和显性效应h_a分别为17.739和17.682,显性度h_a/d_a 小于1。ABC尺度测验结果表明,叶绿素含量的遗传符合加性-显性模型。2种方法分析结果表明,苦瓜叶片叶绿素含量由1对主基因控制,同时受微效多基因及环境影响,适合进行早代选择。B₂、F₂世代应重点进行主基因选择,多基因在B₁选择效率高,提高品系叶绿素含量应注重对加性效应和显性效应的利用。该研究结果为苦瓜产量及品质育种提供了理论基础。     

苦瓜白粉病抗性的主基因+多基因混合遗传模型分析

通过统计苦瓜白粉病的病情指数,研究白粉病抗性的遗传规律。采用主基因+多基因混合遗传分离分析法对抗病品系04-17-3和感病品系25-1杂交组合的P1、P2、F1、F2、B1和B2共6个世代群体抗白粉病遗传进行研究。结果表明：苦瓜对白粉病的抗性遗传符合2对加性-显性-上位性主基因+加性-显性多基因模型（E-1）,抗病对感病为不完全隐性;2对主基因的加性效应值均为-12.00;2对主基因分别具有正向部分显性和正向超显性作用,加性效应值均大于其显性效应值,上位性效应值（i+jab+jba+l）为负值。从遗传率上看,回交世代和F2的主基因的值分别为55.14％、43.56％和95.22％,多基因的值分别为16.10％、26.57％和0,环境变异在4.78％~29.87％间。主基因和多基因共同决定了苦瓜对白粉病的抗性,以主基因遗传为主,同时还受到环境变异的部分影响。在白粉病抗性育种过程中,应注意利用加性效应,选用白粉病抗性基因较多的材料作为亲本,并在早代进行选择,尤其是F2代主基因选择效率最高。     

基于“华占”的强优势杂交组合的株高与主穗长遗传分析

株高与穗长是水稻品种的关键性状,有效利用水稻性状间的杂种优势是培育高产品种的关键技术手段。以“华占”配制的‘天优华占’‘恒丰优华占’‘五丰优华占’3个杂交组合为供试材料,构建了包含P₁、P₂、F₁、F₂、BC_1-1、BC_1-2等6个遗传世代群体。采用植物数量性状“主基因+多基因”混合模型分析了株高和主穗长的遗传方式。结果表明：3个杂交组合的株高和主穗长遗传均符合MX2-ADI-ADI遗传模型。在“华占”为遗传背景中,3个群体F₂、BC_1-1、BC_1-2的株高均以多基因控制为主,多基因遗传率变幅分别为72.11%~75.42%、76.92%~86.28%和68.13%~75.13%,育种后代中应在高世代选择。3个群体F₂代中的主穗长主基因遗传率分别为81.99%、68.95%和90.01%,多基因遗传率分别为12.16%、23.78%和3.52%;在回交群体中,3个组合的主穗长主基因和多基因遗传率与回交亲本密切相关,育种上应根据群体遗传特性进行相应的选择策略。     

波斯小麦Cypa35-3成株期抗白粉病基因定位

源自苏联的波斯小麦Cypa35-3对陕西关中地区白粉菌优势小种表现为成株期高抗白粉病。为明确Cypa35-3抗白粉病基因所在染色体位置及其抗白粉病基因的遗传规律,利用Cypa35-3与高感白粉病的加拿大二粒小麦Flavescens进行杂交,在成株期自然发病条件下对亲本及其杂交F₁、F₂、F_2∶3群体进行白粉病抗性评价与遗传分析;选用分布于A、B染色体组14对染色体上共计601对SSR标记,利用分离群体分组分析法(BSA)对Cypa35-3的F₂群体进行多态性标记筛选。结果表明,Cypa35-3的成株期白粉病抗性受1对显性基因控制,暂命名为PmCypa35-3。通过群体筛选,获得4对位于1B染色体上的SSR标记,分别为Xbarc81、Xcfd48、Xbarc61、Xbarc302,其中Xbarc81、Xcfd48位于PmCypa35-3两侧,遗传距离分别为25.2 cM、8.6 cM。由此将成株期抗白粉病基因PmCypa35-3初步定位于1B染色体。通过与1B染色体上及波斯小麦中正式命名的抗白粉病基因...     

玉米品种通育189的雄穗分枝数F1平均优势及遗传分析

针对PH6WC、PH4CV、B20、D1279及PH6WC×PH4CV、PH6WC×B20、PH6WC×D1279、D1279×PH6WC鉴定试验进行雄穗分枝数差异分析,PH6WC×D1279(通育189)组建6世代群体(P₁、P₂、F₁、B₁、B₂、F₂),运用主-多基因混合模型遗传分析方法对雄穗分枝数遗传进行分析。结果表明,通育189雄穗分枝数存在细胞质遗传效应,F₁雄穗分枝数平均优势为28.57%～132.41%;雄穗分枝数遗传模型为2对主基因加、显、上+多基因加、显混合模型,2对主基因为正向完全显性,主基因上位性效应>显性效应>加性效应;主基因效应是多基因效应的41.25倍,主基因遗传率为27.58%～88.87%,多基因遗传率为0～41.78%。     

玉米高淀粉含量育种进步与遗传效应研究

针对2021年国家玉米品种区域试验及2019、2020、2021年内蒙古自治区生产试验淀粉含量≥75%的品种或组合进行分析，对PH6WC×PH4CV、PH6WC×B20、PH6WC×D1279及亲本淀粉含量差异进行分析，对PH6WC×D1279组建6世代群体(P₁、P₂、F₁、B₁、B₂、F₂)，运用主-多基因混合模型遗传分析方法对淀粉含量遗传进行分析。结果表明，我国玉米高淀粉含量育种水平进步显著，实现了高产、高淀粉含量、广适性的良好结合。F1淀粉含量显著或极显著高于亲本，F₁超高亲优势为1.72%～2.54%。淀粉含量遗传模型为2对主基因加、显、上模型，主基因显性效应>上位性效应>加性效应，遗传率为80.58%～82.68%。     

苦瓜枯萎病抗性材料 Thai4-6 的遗传模型分析

苦瓜枯萎病是尖孢镰刀菌苦瓜专化型引起的真菌病害,探明苦瓜枯萎病的抗性遗传机制对制定抗病育种策略具有现实指导意义。本文以抗枯萎病苦瓜材料 Thai4-6 和感病材料 CN19-1 为亲本配制杂交组合,基于该组合 6 世代遗传群体（P1、P2、F1、F2、BCP1 和 BCP2）,采用主基因+多基因混合遗传模型分析枯萎病抗性遗传特性。 数据分析结果表明,该杂交组合的枯萎病抗性呈连续分布,最适模型为 2 对加性-显性-上位性主基因+加性-显性多 基因遗传模型（E-1）,2 对主基因加性效应值均为–13.85,显性效应值分别是 25.58 和 34.26,主基因遗传率在 BCP1、 BCP2 和 F2 中分别是 86.03%、80.34%和 94.25%,表明该组合枯萎病抗性主要受 2 对主基因控制。环境因素引起的 变异在 3 个分离世代群体中分别占 13.97%、14.06%和 5.75%。本研究可为抗枯萎病苦瓜育种提供理论依据。     

高油酸花生种质油酸亚油酸含量的主基因+多基因遗传

应用植物数量性状主基因+多基因混合遗传模型对杂交组合8-153×粤油13的P1、F1、P2、F2世代和F2∶3家系的油酸、亚油酸含量进行多世代联合分析,结果表明:在该组合中,花生油酸含量遗传由2对加性-显性主基因+多基因控制;F2、F2∶3群体主基因遗传率分别为77.28%和55.00%,多基因遗传率分别为13.34%和32.13%;两对主基因的加性效应值分别为8.8172和4.0397,显性效应值分别为-10.2475和-9.0420。亚油酸含量遗传由2对加性-显性-上位性主基因控制;F2、F2∶3群体主基因遗传率分别为88.30%和79.84%;两对主基因的加性效应值(da、db)分别为-7.3949和-6.9568,显性效应值(ha、hb)分别为1.3879和1.5438;da与db、da与hb、db与ha以及ha与hb间的互作效应分别为-4.5216、-1.7688、-1.9808和-1.1172。ol基因的多效性以及油酸、亚油酸含量和O/L比值的遗传均受两对主基因控制的结果暗示相同的两对主基因可能同时控制油酸与亚油酸含量,它们对油酸、亚油酸含量的作用效应相反。     

甘蓝型油菜主要脂肪酸的主基因+多基因遗传分析

以低芥酸油菜品系APL01与高芥酸品种M083杂交所获得的6个基本世代（P1、P2、F1、B1、B2和F2）为材料，利用主基因+多基因混合遗传模型对油菜主要脂肪酸进行遗传分析，结果表明：棕榈酸和廿碳烯酸均由2对加性-显性-上位性主基因+加性-显性多基因控制，棕榈酸的主基因以显性效应为主，加性效应较小，廿碳烯酸的主基因加性效应与显性效应并重。硬脂酸、油酸、亚油酸和亚麻酸均由2对加性-显性-上位性主基因+加性-显性-上位性多基因控制，硬脂酸的主基因以加性效应为主，显性效应较小，主基因的遗传率为75.00%~92.45%，多基因的遗传率较小；控制油酸的2对主基因的加性效应值分别为14.38和9.92，显性效应值分别为-2.24和-0.44，上位性效应以加加上位为主，主基因的遗传率较大，为81.93%~92.68%，多基因的遗传率较小；控制亚油酸及亚麻酸的主基因加性效应均大于显性效应，上位性效应中以加加上位和显显上位为主。芥酸由2对加性-显性主基因控制，加性效应为-12.27和-8.83，显性效应值较小，分别为0.35和1.69，无上位性效应，也无多基因存在，主基因的遗传率较大，为92.54%~96.72%。     

多群体解析高油花生籽仁含油量的遗传效应

为探讨高油花生品系农大D666含油量的遗传模式,以农大D666为中心亲本配置了4个杂交组合(DP、PD、SD、3D),同时利用农大D666的亲本丰花2号和Krapt.st.16配置了正、反交组合(FP、PF),以上述6个组合的F_2群体为材料进行含油量的主基因+多基因遗传模型分析。结果表明,6个F_2群体的含油量均存在广泛的变异和超亲现象,呈连续分布,符合数量性状遗传特征。DP和PD组合的亲本含油量差异较小,F_2群体含油量均值较高,分别为54.29%和54.02%,变异系数较小,分别为3.38%和3.90%;SD和3D组合的亲本间含油量差异较大,F_2群体含油量均值仅为52.66%和51.75%,变异系数分别是5.51%和6.24%;FP和PF组合的F_2群体含油量均值分别为50.30%和51.52%,变异系数分别为6.30%与6.00%。6个群体的含油量分别符合3种遗传模型:DP和PD含油量符合无主基因遗传模型(0MG),受微效多基因控制;SD和3D符合2对主基因的加性-显性-上位性遗传模型(2MG-ADI),加性效应与显性效应均为正向调控,以加性效应为主,主基因遗传率分别为33.64%和37.80%,2个群体基因效应值相近,增效基因来自高油亲本;FP和PF符合2对主基因的等显性遗传模型(2MG-EAD),主基因遗传率分别为51.17%和63.56%,正、反交组合的遗传模式相同,表明含油量以细胞核遗传为主,加性效应均为正值,增效基因来自高油亲本。综合分析表明,农大D666含油量性状的超亲现象一方面是受其亲本Krapt.st.16的2个主效基因控制,另一方面存在多个微效基因的累加效应。     

大麦白粉病抗性的遗传分析

为给大麦抗白粉病育种提供参考依据,以1个感白粉病、4个抗白粉病大麦品种为亲本,按Griffing的双列杂交法Ⅰ配制20个杂交组合,在田间自然条件下研究了大麦白粉病抗性的遗传特性。结果表明,大麦白粉病抗性在杂交组合间存在显著差异。5个亲本中,木石港3号和CM72的一般配合力较好,均表现为较大的负向效应,能极显著提高杂种后代抗白粉病能力;S096的一般配合力中等,也表现为负向效应,能显著地提高杂种后代抗白粉病能力,因而这三个品种在大麦抗白粉病育种中利用价值较高。大麦白粉病抗性遗传符合加性显性模型,同时受加性和显性效应的作用,且加性效应更重要。大麦白粉病抗性的狭义遗传力较低,早代选择不宜太严。     

Local and systemic control of powdery mildew (Leveillula taurica) on pepper plants by foliar spray of mono-potassium phosphate

A foliar spray of 1% (w/v) solution of the fertilizer mono-potassium phosphate (MKP) (KH₂PO₄) on the upper surfaces of lower leaves of greenhouse-grown peppers induced local and systemic control against Leveillula taurica, as compared with control plants. This protection was expressed by a reduction in the leaf area covered with sporulating colonies and in conidial production on leaf tissue, 24 or 48 h post-treatment, when MKP was applied on lower leaves of plants that had been exposed to the source of inoculum. Foliar application of MKP, initiated before or after exposure to heavily diseased plants as the source of inoculum, was effective in controlling powdery mildew. Application of MKP efficiently suppressed powdery mildew as expressed by inhibition of the development of new sporulating colonies, as well as the conidial production of the fungus on infected tissue. Microscopic examination indicated destruction of both hyphae and conidial structures on MKP-treated leaves. The efficacy of MKP in controlling powdery mildew on greenhouse-grown plants was compared with a sterol-inhibiting systemic fungicide. Both treatments significantly inhibited powdery mildew as compared with non-treated control plants, although the fungicide-based treatment seemed to be slightly more effective (not significant) in controlling the disease. Phosphate solutions were not phytotoxic to plant tissue and did not affect the yield, as compared with the fungicide treatment. However, a lower yield was recorded for the non-treated control plots because of mildew infection on leaves. These data indicate that MKP spray may be applied as an alternative practice for the control of powdery mildew in peppers.     

Prediction criteria of promising F3 populations in durum wheat: A comparative study

Effective selection of parental material and promising segregating populations is an essential requirement for breeding success. There are many contradictive reports about the best parent selection criterion for the development of promising crosses. For the clarification of this problem field experiments were conducted for four consecutive years to compare the effectiveness of six criteria for the prediction of the most promising F₃ populations in durum wheat (Triticum durum L.): the mid-parent value, the F₁, the F₂, the (F₁ + F₂)/2, and the genetic distance among the parents as it is calculated using the SSR and RAPD molecular markers. During the first growing season (2003–2004) nine commercial cultivars of durum wheat and four landraces were crossed. The following growing season (2004–2005), 17 crosses (F₁ generation) were evaluated under low plant density (1.15 plants m⁻²) in a replicated (R-21) honeycomb design. During the third growing season (2005–2006), the four highest yielding crosses, one cross with an intermediate yield, and the three crosses with the lowest yield (F₂ generation) were evaluated under low plant density in a R-9 honeycomb design. Finally, in the fourth growing season (2006–2007) progeny of the aforementioned eight crosses (F₃ generation) and the ten parents were evaluated in a randomized complete block design in two locations. Furthermore, the genetic distance among the parents was determined using the SSR and RAPD molecular markers. It was observed that the three F₃ populations with the lowest yielding ability were the ones with the lowest mid-parental value. In addition, one of the two top F₃ populations was second in the rank according to the mid-parental value. Furthermore, the two top F₃ populations were also the highest yielding in the F₁ and F₂ generations. On the contrary, none of these crosses were predicted by the genetic distance as it was calculated using the SSR and RAPD molecular markers. It was concluded that parental pairs with high mid-parental value and high combined yield (F₁ + F₂)/2 obtained after evaluation of their F₁ and F₂ at low plant density was the most effective way to predict promising F₃ populations.     

基于SLAF-seq技术的苦瓜白粉病SNP分子标记开发

以高抗白粉病苦瓜MC18和高感白粉病MC105杂交构建遗传分离群体,利用SLAF-seq技术进行深度测序,开发与抗白粉病性状紧密关联的SNP分子标记。结果表明:测序共获得各样品的有效reads为10.48 Mb,获得高质量的SLAF标签91 856个,其中多态性SLAF标签5 502个,多态性比例为5.99%。通过对多态性SLAF标签进行关联分析,筛选出与苦瓜白粉病抗病性状紧密关联的SNP位点共29个。根据关联分析结果 ,通过四引物扩增受阻突变体系PCR技术进行SNP位点多态性的验证,其中Marker4542、Marker11188分子标记特异性强、灵敏度高、稳定性好,建立一套简便快捷的苦瓜SNP分型方法。该方法可对苦瓜育种材料进行分子标记辅助选择,以进一步提高苦瓜抗病育种效率。      

基于倾斜遥感观测的小麦白粉病胁迫下叶绿素含量监测

为了探讨多角度遥感在白粉病胁迫下监测小麦叶绿素含量的适宜角度,以易感白粉病品种偃展4110和中感白粉病品种国麦301为试验材料,获取三种不同生长环境(病圃田、接种田和自然感病田)下抽穗至灌浆期小麦冠层多角度反射光谱及叶绿素含量,分析不同时期叶绿素含量变化及其与多角度反射率的关系,建立白粉病胁迫下小麦叶绿素含量监测模型。结果表明,由红边波段构建的光谱参数对白粉病胁迫下叶绿素含量变化反应敏感。优化筛选出的植被指数与叶绿素含量之间的相关性在前向角度观测时优于垂直角度观测,而垂直观测角度好于后向角度观测,整体上以前向20°最佳。植被指数中,光谱参数RES(红边对称度)表现较好,在前向20°下的监测精度达0.725。因此,在前向20℃观察条件下可用RES对白粉病危害后小麦冠层叶绿素含量变化进行有效监测。     

一个水稻白化致死突变基因的精细定位和遗传研究

从粳稻品种日本晴经⁶⁰Co诱变的M₁代材料中发现了一个白化致死突变体,该突变体从萌芽后一直表现白化,3叶期后逐渐衰亡。遗传分析表明,该突变表型受一对隐性核基因控制,将该白化突变体暂定名为 al14。与野生型相比, al14突变体的叶绿素含量与类胡萝卜素含量显著降低。电子显微镜观察表明 al14突变体不能形成完整的叶绿体,只有原片层体结构。对叶绿体编码基因的表达分析发现,突变体中光系统Ⅰ和光系统Ⅱ基因表达明显下调,核糖体结构基因和质体编码的RNA聚合酶亚基基因表达明显上调,但是PsbN(photosystem Ⅱ protein N)却上调表达水平最高,达到118.23倍。利用 al14 突变体与黄华占杂交获得的F₂代分离群体进行基因定位,将该基因定位于水稻第6染色体上约40 kb的范围。目前,该范围内没有叶色相关基因的报道,可能为一新的调控叶绿体发育的基因。     

Genetic Analysis of Early Generation Stability in Rice

The mechanism of early generation stability （EGS） in rice was studied via genetic analysis. Three types of crosses were made, namely between EGS varieties, EGS and conventional rice variety, and conventional rice varieties. The genetic analysis was based on the stable lines in F2 population. The stable lines may appear from some combinations of EGS rice crossing with each other and EGS rice crossing with conventional varieties at different frequencies, but stable lines didn＇t appear in conventional varieties crossing with conventional varieties. Genetic analysis results indicated that the EGS phenomena should just exist in special rice materials, and the frequency of stable lines was closely related to the EGS traits of parents. The EGS traits were neither qualitative nor quantitative traits, and they were controlled by neither dominant genes nor recessive genes. The EGS traits might be inherited by F1 single plant, and the traits of F3 and F4 were corresponded to those of F2 population, i.e. F3 and F4 lines derived from non-segregating F2 showed uniform agronomic traits, and those from segregating F2.did not. The agronomic traits of EGS lines were consistent with those of F1 single plant. On the other hand, when EGS lines occurred, the segregating lines in Mendelian manner were also observed in all F2 population of the same combination. It was suggested that the reason why the stable strains occurred might be a special factor to control （open/close） gene at the beginning of cell division in zygote, resulting in closing mitosis and opening somatic reduction. The somatic reduction of zygote resulted in recombination and homozygosity forming in F1 single plant, and some lines with uniform agronomic traits were observed in some lines of F2 population.     

我国主要麦区101个小麦生产和区试品种（系）及高代品系抗白粉基因推导

为了明确我国小麦品种（系）中抗白粉基因的组成,利用基因推导法对来自我国主要麦区的101个小麦品种（系）进行了抗白粉病基因推导。结果表明,近一半的供试生产品种对所有供试菌株表现感病;供试的大多数区试品种具有有效地抗白粉基因,应加快这些抗病品种的大面积推广;近1/3的高代品系含有有效地抗白粉基因。供试小麦生产品种和区试品种（系）及高代品系中具有已知的抗白粉基因主要有Pm4b、Pm8、Pm2 Mld、Pm4a、Pm2、Pm2 6、Pm30等。此结果对于我国小麦白粉病的抗病育种和品种布局有重要的参考价值。     

甘蓝型油菜矮秆新种质LSW2018矮缩性状遗传规律研究

甘蓝型油菜LSW2018苗期具有典型的"矮缩"性状,植株矮秆,茎秆粗壮,抗倒性极强,是理想的矮秆种质资源,适宜机械化作业,具有重要的利用价值.为挖掘LSW2018的育种优势,研究其"矮缩"性状的遗传规律,选用119份正常高秆甘蓝型油菜品种(系)、12份白菜型油菜品种(系)、6份芥菜型油菜品种(系)与LSW2018(P1...