烯效唑生物学效用研究进展

烯效唑是一种高效低毒的三唑类植物生长延缓剂,兼有良好的杀菌作用。它通过降低贝壳杉烯氧化酶活性,阻碍GA的生物合成从而抑制植物生长。烯效唑使植株体内产生一系列的生理效应,对促进植株矮健、抗倒伏和防衰老等都具有明显效果,尤其是在作物面对逆境(如干旱、高温、低温、盐害、内涝和病害等)的胁迫时,烯效唑能显著增强作物对逆境的抵抗能力,从而达到增产目的。本文对国内外有关烯效唑的作用机理、应用效果及抗逆性表现等方面的研究进展进行综述。     

2种低毒杀虫剂防治水稻粘虫示范试验

为合理使用低毒农药防治水稻粘虫,2015年7月在广西乐业县同乐镇和甘田镇进行25%灭幼脲悬浮剂和2.2%甲氨基阿维菌素苯甲酸盐微乳剂防治粘虫大田示范试验。结果表明:施药后17 d,核心区25%灭幼脲对粘虫的防治效果和保叶率分别为96.19%和94.73%,在培训指导农民防治示范区的防效分别为93.50%和95.10%;施药后10 d,核心区2.2%甲氨基阿维菌素苯甲酸盐对粘虫的防治效果和保叶率分别为96.61%和97.35%,在培训指导农民防治示范区的防效分别为90.07%和89.59%。25%灭幼脲和2.2%甲氨基阿维菌素苯甲酸盐处理区对粘虫的防效均要高于农民自防区。     

Identification and validation of root length QTLs for water stress resistance in hexaploid wheat (<Emphasis Type="Italic">Titicum aestivum</Emphasis> L.)

Thorough understanding of the genetic mechanisms governing drought adaptive traits can facilitate drought resistance improvement. This study was conducted to identify chromosome regions harbouring QTLs contributing for water stress resistance in wheat. A RIL mapping population derived from a cross between W7984 (Synthetic) and Opata 85 was phenotyped for root length and root dry weight under water stress and non-stress growing conditions. ANOVA showed highly significant (p ≤ 0.01) variation among the RILs for both traits. Root length and root dry weight showed positive and significant (p ≤ 0.01) phenotypic correlation. Broad sense heritability was 86% for root length under stress and 65% for root dry weight under non-stress conditions. A total of eight root length and five root dry weight QTLs were identified under both water conditions. Root length QTLs Qrln.uwa.1BL, Qrln.uwa.2DS, Qrln.uwa.5AL and Qrln.uwa.6AL combined explained 43% of phenotypic variation under non-stress condition. Opata was the source of favourable alleles for root length QTLs under non-stress condition except for Qrln.uwa.6AL. Four stress specific root length QTLs, Qrls.uwa.1AS, Qrls.uwa.3AL, Qrls.uwa.7BL.1 and Qrls.uwa.7BL.2 jointly explained 47% of phenotypic variation. Synthetic wheat contributed favourable alleles for Qrls.uwa.1AS and Qrls.uwa.3AL. Two stable root dry weight QTLs on chromosomes 4AL and 5AL were consistently found in both water conditions. Three validation populations were developed by crossing cultivars Lang, Yitpi, and Chara with Synthetic W7984 to transfer two of the QTLs identified under stress condition. The F_2.3 and F_3.4 validation lines were phenotyped under the same level of water stress as RILs to examine the effect of these QTLs. There were 13.5 and 14.5% increases in average root length due to the inheritance of Qrls.uwa.1AS and Qrls.uwa.3AL, respectively. The result indicated that closely linked SSR markers Xbarc148 (Qrls.uwa.1AS) and Xgwm391 (Qrls.uwa.3AL) can be incorporated into MAS for water stress improvement in wheat.     

棉花纤维中木质素的相对分子量

分子量是聚合物的重要特性之一,木质素的分子量及其分布是研究苯丙烷类结构的反应、物理化学特性和评价其改性产物质量的内容之一。本研究以陆地棉TM-1成熟纤维为材料,分别利用酶解-温和酸解木质素法和二氧六环法提取棉纤维中木质素,结合凝胶渗透色谱法(gel permeation chromatography,GPC)调查和评价2种方法获得的棉纤维中木质素的相对分子量。结果表明,经二氧六环处理提取的棉花纤维中的木质素(dioxane lignin,DL)的重均分子量为2924g mol~(–1)、数均分子量2403 g mol~(–1),略高于由酶解-温和酸解处理提取的木质素(enzymatic hydrolysis-mild acidolysis lignin,EMAL)的重均分子量(2169 g mol~(–1))和数均分子量(1970 g mol~(–1)),EMAL的多分散系数稍低,说明木质素的均一性比DL高。表明EMAL法提取的木质素更适用于分析棉纤维中木质素的相对分子量。利用EMAL法分析棉纤维中木质素相对分子量表明,不同棉花品种的木质素重均分子量分布范围为938~2169 g mol~(–1),数均分子量分布范围为857~1970 g mol~(–1),多分散性系数在1.09~1.74间,均小于2。重均分子量与纤维马克隆值呈显著负相关,数均分子量与纤维长度呈显著负相关,与纤维马克隆值呈极显著负相关。     

水稻紫鞘染色体片段代换系Z519的鉴定及PSH1候选基因分析

花青素是广受人们喜爱的植物色素,在食品加工、杂种纯度鉴定中具有重要的作用。本研究鉴定了一个以日本晴为受体、优良紫鞘恢复系R225为供体亲本的紫鞘水稻染色体片段代换系Z519。Z519共含有16个代换片段,分布于除第10染色体外的其他11条染色体,平均长度为6.85 Mb。Z519在芽鞘3 mm时鞘尖呈现紫色,其后在叶鞘、叶缘、茎维管束和柱头等部位出现紫色线条,而日本晴各部位均为绿色。Z519叶鞘中花青素含量极显著高于日本晴,剑叶中没有显著差异。与受体日本晴相比,Z519的株高显著降低,千粒重、主穗总粒数和实粒数显著增加,有效穗数、主穗长和结实率无显著差异。进一步以日本晴与Z519杂交产生的F1和F2群体对紫鞘基因进行了遗传分析和分子定位。该紫鞘表型受显性单基因控制,位于第1染色体In Del标记L03和SSR标记L01之间37.8 kb的区域,被命名为PSH1。对该区间进行候选基因预测和测序,Z519在一个编码质体ATP/ADP转运蛋白的LOC_Os01g45910基因第一外显子的第238~252碱基的GTG重复区又多插入了GTG 3个碱基,导致增加了一个甘氨酸。q RT-PCR结果进一步表明其表达量在Z519中明显降低,初步确定LOC_Os01g45910是PSH1的候选基因。该研究为PSH1调控花青素的分子机制奠定了良好基础。     

Involvement of TLR4/NLRP3 inflammasome in contrast medium-induced inflammation and injury in renal tubular epithelial cells

AIM: To investigate whether Toll-like receptor 4 (TLR4) and Nod-like receptor protein 3 (NLRP3) inflammasome were involved in contrast medium (CM)-induced inflammation and injury in renal tubular epithelial cells. METHODS: Iopromide was used to injure NRK-52E cells in the study. The cell viability was measured by CCK-8 assay. The protein levels of TLR4, NLRP3, apoptosis-associated speckle-like protein (ASC), caspase-1 and cleaved caspase-3 were determined by Western blot. The releases of interleukin (IL)-1β and IL-18 were detected by ELISA. The apoptotic rate was evaluated by Hoechst staining, and mitochondrial membrane potential (MMP) was analyzed by JC-1 staining. siRNA was transfected into the NRK-52E cells to silence NLRP3 expression. RESULTS: CM decreased the viability of NRK-52E cells (P<0.05). CM also elevated the protein levels of cleaved caspase-3, TLR4, NLRP3, IL-1β and IL-18 (P<0.05). Silencing NLRP3 attenuated CM-induced releases of inflammatory cytokines. Moreover, treatment with TLR4 inhibitor TAK-242 or knockdown of NLRP3 by siRNA transfection both attenuated cell apoptosis and loss of MMP caused by CM. CONCLUSION: TLR4/NLRP3 inflammasome takes part in the pathogenesis of CM-induced acute kidney injury, and mediates CM-induced injury and inflammation in renal tubular epithelial cells.     

Effect of exogenous hydrogen sulfide on lipophagy in mouse primary hepatocytes

AIM: To evaluate the effect of exogenous hydrogen sulfide (H₂S) from GYY4137 on lipophagy in mouse primary hepatocytes. METHODS: The C57BL/6 mouse primary hepatocytes isolated and cultured by 2-step in situ perfusion method were divided into 4 groups: the cells in control group were incubated with normal medium; the cells in model group were incubated with 1.2 mmol/L oleic acid (OA) for 48 h; the cells in H₂S group or propargylglycine (PAG) group were incubated with 1.2 mmol/L OA for 48 h followed by serum-free phenol red-free RPMI-1640 medium which contained 1 mmol/L GYY4137 or 200 μmol/L PAG for 6 h. The cells were collected to conduct immunofluorescence staining of LC3 and photography under fluorescence microscope, phase-contrast microscope or transmission electron microscope. The protein expression of LC3-Ⅰ/Ⅱ in the hepatocytes was determined by Western blot. RESULTS: In contrast with the model group, the fluorescent particles of LC3, the protein expression of LC3, the number of autophagic lysosome and vacuoles in hepatocytes in H₂S group increased. CONCLUSION: In steatosis hepatocytes, exogenous H₂S promotes the lipophagy.     

番茄绿果与橙果间果实颜色及主要色素含量的遗传研究

对番茄组合绿樱(绿果)×金珠1号(橙果)的6个世代遗传群体(P1、P2、F1、BC1、BC2和F2)进行果色性状、番茄红素含量、叶绿素含量和胡萝卜素含量等的遗传规律分析。结果表明:正反交F1的果色性状无明显差异,而色素含量存在显著差异;说明番茄果色性状受核基因控制,而色素含量遗传除受核基因控制外还可能存在胞质效应。采用多世代联合分析法的分析结果表明,番茄绿果与橙果间的果色性状符合2对加性主基因+加性-显性多基因(MX2-A-AD)遗传模型,其BC1、BC2和F2主基因遗传率分别为73.42%、78.25%和61.41%,多基因遗传率分别为22.87%、15.35%和34.94%,即果色性状遗传的主基因遗传力较强;叶绿素含量符合1对负向显性主基因+加性-显性多基因(MX1-AEND-AD)遗传模型,其BC1、BC2和F2主基因遗传率分别为0、1.73%和0.65%,多基因遗传率分别为45.47%、0和37.82%,即主基因遗传力在BC2群体中最高,多基因遗传力在BC1群体中最高;番茄红素含量与胡萝卜素含量均符合2对加性-显性-上位性主基因+加性-显性多基因(MX2-ADI-AD)遗传模型,其BC1、BC2和F2主基因遗传率分别为75.74%、1.79%、84.26%和61.53%、87.21%、81.05%,多基因遗传率分别为20.32%、74.12%、12.68%和0.68%、0、0,表明番茄红素含量和胡萝卜素含量的主基因遗传力较强。     

红蓝光质对转色期间番茄果实主要品质的影响

采用LED精量调制光源,以番茄品种‘Micro-Tom’为试材,设置红光(R)、蓝光(B)和红蓝组合光3︰1(3R1B)3个处理,以白光(W)为对照,研究红蓝光质对转色期间番茄果实主要品质及番茄红素生物合成关键酶基因表达的影响。结果表明,与对照相比,红光和3R1B处理可显著提高番茄果实可溶性糖含量和糖酸比,降低可滴定酸含量;蓝光下维生素C、可溶性蛋白和可滴定酸含量明显升高,可溶性糖含量较低,但与对照差异不明显。随着果实成熟,红光和3R1B处理下番茄红素含量及牻牛儿基牻牛儿基焦磷酸合成酶(GGPS)和八氢番茄红素合成酶(PSY)基因的表达量显著高于蓝光和对照,尤以3R1B处理最明显;蓝光则显著降低了番茄红素含量,GGPS和PSY1表达受到抑制。综上,蓝光能够促进维生素C、蛋白质和有机酸含量增加;红光和红蓝组合光则有利于碳水化合物的积累,且通过提高番茄红素生物合成关键酶基因GGPS和PSY1的转录水平和活性,促进番茄红素合成,尤以3R1B处理最佳。说明适宜比例的红蓝组合光有利于番茄果实转色,提高果实品质。     

Effects of noninvasive delayed limb ischemic preconditioning on prognosis of myocardial infarction

AIM: To study the effects of noninvasive delayed limb ischemia preconditioning (NDLIP) on animal cardiac function, myocardial morphology and myocardial apoptosis after myocardial infarction (MI). METHODS: Healthy SD male rats[n=45, weighing (250±10) g] were randomly divided into 3 groups:MI group:the animal model of MI was established by surgical ligation of left anterior descending artery (LAD) after 2 weeks; NDLIP group:after the success of the MI animal model, NDLIP was carried out every other day until the 4th, 6th and 8th weeks; sham group:as the negative control group, the animals were taken heart LAD threading but no ligation. All rats were fed conventionally. At the end of the 4th, 6th and 8th weeks, all rats were made ventricular intubation, and then the hemodynamic parameters were recorded. The blood samples were withdrawn from the abdominal aorta and the serum was separated via centrifugation. The serum contents of Bcl-2 and Bax were measured by ELISA. Left ventricular anterior wall was homogenized. The mitochondrial respiratory chain complexes Ⅰ, Ⅱ, Ⅲ and Ⅳ in the myocardial tissues were detected by ELISA. RESULTS: At the end of the 4th, 6th and 8th weeks, compared with MI group, left ventricular systolic pressure in NDLIP group was significantly increased, while left ventricular end-diastolic pressure in NDLIP group was significantly decreased (both P<0.05). Mitochondrial respiratory chain complexesⅠ, Ⅱ, Ⅲ and Ⅳ in NDLIP group were significantly increased (P<0.05). The serum level of Bcl-2 in NDLIP group was significantly increased and Bax level was reduced remarkably (both P<0.01). CONCLUSION: NDLIP improves the hemodynamic indexes, promotes the mitochondrial respiratory function and inhibits cell apoptosis, thus improving the prognosis of MI.