大豆滞绿(stay-green)突变体诱变后代表型性状变异分析

本文利用大豆滞绿突变体Z-94320经60Co-γ射线诱变的突变体后代M5、M6代为材料,进行两年的田间性状观察记录统计,用相关性分析、主成分分析、聚类分析对其17个主要表型性状统计分析。结果表明:诱变后代产生了丰富的变异,出现了多种种皮色和子叶色,产生了非滞绿性状,形成了各种生育周期,且分离出晚熟性状。通过相关性分析发现,单株粒重与株重、茎粗、主茎荚数、分枝荚数、一粒荚数、二粒荚数、三粒荚数、瘪粒荚数、虫食数呈极显著正相关,这些性状可以对产量进行预测;主成分分析在M5代提取出“产量因子”、“株型因子”、“粒荚因子”、“茎荚因子”四个主成分,对农艺性状累计贡献率达到70.50%,M6代提取出“产量因子”、“虫害因子”、“株型因子”、“茎杆因子”四个主成分,对农艺性状累计贡献率达到71.54%;聚类分析将M5、M6代材料分别划分为6类,发现同代中各类群农艺性状情况大致相似,但是各农艺性状在两代之间的变化明显,在株重、结荚高度、单株粒重等方面M6代显著高于M5代,并筛选出两株高产品系和一株特色滞绿品系。本研究逐步完善了对滞绿大豆突变体库的构建,为滞绿大豆诱变后代的遗传多样性研究提供了基础的数据分析。     

一种快速、无损大豆种子DNA提取方法的建立和应用

基因分型是进行植物基因功能的遗传分析和分子标记辅助育种的重要环节。该研究以大豆(Glycine max)成熟种子为材料, 建立了通过钻孔采集样品、快速提取DNA进行基因型鉴定的方法。用此方法, 一个熟练的工作人员可以在1个小时内完成120个样品的采集和DNA提取; 同时种子钻孔取样后, 不会对大豆种子的萌发造成影响。利用该方法获得的DNA可满足PCR扩增的要求。实验重复性好, 成功率在98%以上。这种快速且无损的大豆种子基因型鉴定方法可以用于鉴定杂交种子、品种纯度以及遗传分析等研究工作。     

两株内生芽孢杆菌对盐胁迫下大豆幼苗超氧化物歧化酶和过氧化物酶活性影响

【背景】盐胁迫环境严重影响大豆幼苗生长,内生菌可提高作物的抗逆性。【目的】探究接种内生枯草芽孢杆菌127和解蛋白芽孢杆菌133对盐胁迫下大豆幼苗体内超氧化物歧化酶(superoxide dismutase,SOD)和过氧化物酶(peroxidase,POD)活性的影响。【方法】以“徐豆20”为实验材料,采用盆栽实验法,设置对照组、盐胁迫组和盐胁迫接菌组,在人工气候培养条件下,用不同NaCl浓度(50、100、150、200、250和300 mmol/L)处理大豆幼苗,并接种不同OD600值(OD0.33、OD0.50和OD0.75)的菌悬液。【结果】培养14 d,接种枯草芽孢杆菌127的菌悬液OD0.33和OD0.75分别在盐浓度300 mmol/L和100 mmol/L时,SOD活性均为1.04 U/g-FW;接种解蛋白芽孢杆菌133的菌悬液OD0.50在盐浓度300 mmol/L胁迫下POD活性最高为7 820 U/(g·min),对大豆幼苗修复效果较显著。培养28 d,接种枯草芽孢杆菌127的菌悬液OD0.50,在150 mmol/L时SOD活性最高(0.88 U/g-FW);接...     

大豆异黄酮浸种对盐胁迫大豆幼苗的生理效应

大豆异黄酮( Soybean isoflavones)是在大豆生长过程中形成并在成熟种子和叶片中积累较多的一类具有生物活性的次生代谢物,通常可作为人们日常生活中的一类营养保健品.研究了外源大豆苷或染料木苷溶液(0.01 mg/L)浸种处理对盐胁迫栽培大豆(N23674品种)和滩涂野大豆(BB52种群)及其经逐代耐盐性筛选的杂交后代(4076株系,F5)幼苗叶片伤害率、光合作用、Na+含量和Na+/K+值、活性氧清除酶活性及内源大豆异黄酮含量等生理指标的影响.结果表明:盐胁迫下,两种外源大豆异黄酮浸种处理均可显著抑制叶片相对电解质渗透率和硫代巴比妥酸反应物(TBARS)含量的上升及净光合速率(Pn)的下降,降低Na+含量和Na+/K+值,增强超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性,提高内源大豆异黄酮含量,从而表现对盐害的缓解效应,其中对耐盐性较弱的栽培大豆N23674品种效应更明显.这为大豆异黄酮在大豆耐盐育种、化学调控和盐碱地种植利用等提供了理论依据.     

传统豆酱发酵过程中细菌多样性动态

细菌在豆酱发酵过程中起到非常重要的作用,并与豆酱的风味和质量密切相关,因此研究豆酱中细菌的多样性具有重要意义。以自然发酵的豆酱样品为研究对象,采用细菌16S rDNA的部分可变区的PCR-DGGE技术对自然发酵豆酱样品的细菌群落组成和优势菌群进行研究。结果表明,传统豆酱发酵过程细菌群体中既有原始种群的减少和增长,也有次级种群的增多和演变。在整个发酵过程中,初期和末期以不可培养细菌为主,初期细菌群体快速演替,细菌种群多样性指数在发酵42 d和56 d达到两次高峰。     

大豆膨胀素基因GmEXPB5和GmEXPB7生物信息学及表达分析

膨胀素(expansin,EXP)通过调控细胞壁的松弛在植物应对环境胁迫过程中起着重要作用。为研究EXP基因在大豆应对非生物胁迫过程中的作用,该文对大豆中的两个EXP基因(GmEXPB5和GmEXPB7)及其蛋白序列进行生物信息学分析,通过实时荧光定量PCR(qRT-PCR)检测基因表达量。结果表明:(1)GmEXPB5和GmEXPB7分别位于大豆第10号和第12号染色体上,编码的蛋白序列长度分别为272和267个氨基酸。GmEXPB5蛋白分子量为29.07 kD,理论等电点为7.51; GmEXPB7蛋白分子量为29.09 kD,理论等电点为8.66。GmEXPB5和GmEXPB7均为稳定的亲水蛋白且定位于细胞壁中。GmEXPB5和GmEXPB7蛋白均含有一段信号肽序列和一个保守的DPBB_1结构域。(2)GmEXPB5蛋白与鹰嘴豆CaEXPB15蛋白亲缘关系最近,GmEXPB7蛋白与密花豆、赤豆和豇豆的EXPB3蛋白有着较近的亲缘关系。(3)GmEXPB5和GmEXPB7在大豆根、茎和叶中均有表达且它们在根和叶中的表达量均显著高于茎中的表达量。(4)GmEXPB5和GmEXPB7在大豆幼苗中可以响应盐、干旱和低温胁迫。(5)GmEXPB5启动子区域含有2种与逆境相关的顺式作用元件(ABRE和ARE); GmEXPB7启动子区域含有5种与逆境相关的顺式作用元件(ABRE、ARE、CGTCA-motif、TC-rich repeats和MBS)。综上所述,GmEXPB5和GmEXPB7能够参与大豆对非生物胁迫的应答。     

Effect of abscisic acid application on root isoflavonoid concentration and nodulation of wild-type and nodulation-mutant soybean plants

Isoflavonoids (daidzein, genistein, and coumestrol) are involved in induction of nod genes in Bradyrhizobium japonicum and may be involved in nodule development as well. Abscisic acid (ABA) may also impact nodulation since ABA is reportedly involved in isoflavonoid synthesis. The current study was conducted to evaluate whether ABA plays a role in differential nodulation of a hypernodulated soybean (Glycine max L. Merr.) mutant and the Williams parent. Exogenous ABA application resulted in a decrease in nodule number and weight in both lines. Isoflavonoid concentrations were also markedly decreased in response to ABA application in both inoculated and noninoculated soybean roots. The inoculation treatment itself resulted in a marked increase in isoflavonoid concentrations of NOD1-3, regardless of ABA levels, while only slight increases occurred in Williams. The nodule numbers of both soybean lines across several ABA concentration treatments were highly correlated with the concentration of all three isoflavonoids. However, differences in internal levels of ABA between lines were not detected when grown in the absence of external ABA additions. It is concluded that differential nodule expression between the wild type and the hypernodulated mutant is not likely due to differential ABA synthesis.     

大豆品种(系)和种植密度对豆天蛾幼虫存活及生长发育的影响

豆天蛾Clanis bilineata tsingtauica Mell幼虫,是一种食用昆虫,富含蛋白质、维生素和矿质元素,具有很高的营养、药用和经济价值。了解适宜豆天蛾幼虫生长发育的大豆品种（品系）和种植密度,可为豆天蛾幼虫规模化饲养提供理论基础。研究通过设置两因素裂区实验,在10个品种（品系）大豆和2个种植密度水平下,测定豆天蛾幼虫生物学参数,明确适宜豆天蛾幼虫养殖的大豆品种（品系）和种植密度。结果表明,不同大豆品种（系）和种植密度对豆天蛾幼虫存活及生长发育均有显著影响;其中使用连151、淮豆9号、东辛3号和H0573大豆饲养的豆天蛾幼虫产量和存活率较高,虫体长度较长,发育历期较短;大青豆饲养的豆天蛾幼虫产量较低,幼虫发育整齐度较差,发育历期长。当种植密度为40 cm×30 cm时,豆天蛾幼虫存活和发育历期整齐度均显著高于种植密度40 cm×15 cm。综上所述,较适宜豆天蛾幼虫养殖的大豆品种（品系）为连151、淮豆9号、东辛3号和H0573,种植密度为40 cm×30 cm。     

360度群体遗传变异扫描——大豆泛基因组研究

大豆(Glycine max)是重要的油料和蛋白作物, 其丰富的遗传变异为生物学性状挖掘和育种改良提供了重要的资源基础。然而, 单个基因组信息无法全面揭示种质资源的遗传变异, 泛基因组研究为解决这一不足提供了新方案。近日, 中国科学院遗传与发育生物学研究所田志喜和梁承志研究团队从2 898份大豆种质中选取26份代表性材料, 并整合已有的3个基因组, 构建了包含野生和栽培大豆的泛基因组和图基因组(graph-based genome), 鉴定了整个群体的绝大多数结构变异数据集, 确定了大豆种质的核心、非必需和个体特异的基因集。利用这些数据系统地揭示了生育期位点E3的等位基因变异和基因融合事件、种皮颜色基因I的单体型和演化关系以及结构变异对铁离子转运基因表达和地区适应性选择的影响。该研究为作物基因组学研究提供了一个新的模式, 同时将加速推动大豆遗传变异的鉴定、性状解析和种质创新。     

Effects of soybean isoflavones on the growth performance,intestinal morphology and antioxidative properties in pigs

Soybean meal is rich in soybean isoflavones, which exhibit antioxidant, anti-inflammatory, antiviral and anticancer functions in humans and animals. This study was conducted to investigate the effects of soybean isoflavones on the growth performance, intestinal morphology and antioxidative properties in pigs. A total of 72 weaned piglets (7.45 ± 0.13 kg; 36 males and 36 females) were allocated into three treatments and fed corn-soybean meal (C-SBM), corn-soy protein concentrate (C-SPC) or C-SPC supplemented with equal levels of the isoflavones found in the C-SBM diet (C-SPC + ISF) for a 72-day trial. Each treatment had six replicates and four piglets per replicate, half male and half female. On day 42, one male pig from each replicate was selected and euthanized to collect intestinal samples. The results showed that compared to pigs fed the C-SPC diet, pigs fed the C-SBM and C-SPC + ISF diets had higher BW on day 72 (P < 0.05); pigs fed the C-SBM diet had significantly higher average daily gain (ADG) during days 14 to 28 (P < 0.05), with C-SPC + ISF being intermediate; pigs fed the C-SBM diet tended to have higher ADG during days 42 to 72 (P = 0.063), while pigs fed the C-SPC + ISF diet had significantly higher ADG during days 42 to 72 (P < 0.05). Moreover, compared to pigs fed the C-SPC diet, pigs fed the C-SBM diet tended to have greater villus height (P = 0.092), while pigs fed the C-SPC + ISF diet had significantly greater villus height (P < 0.05); pigs fed the C-SBM and C-SPC + ISF diets had significantly increased villus height-to-crypt depth ratio (P < 0.05). Compared with the C-SPC diet, dietary C-SPC + ISF tended to increase plasma superoxide dismutase activity on days 28 (P = 0.085) and 42 (P = 0.075) and reduce plasma malondialdehyde (MDA) content on day 42 (P = 0.089), as well as significantly decreased jejunal mucosa MDA content on day 42 (P < 0.05). However, no significant difference in the expression of tight junction genes among the three groups was found (P > 0.05). In conclusion, our results suggest that a long-term exposure to soybean isoflavones enhances the growth performance, protects the intestinal morphology and improves the antioxidative properties in pigs.