栽培密度对吉杂141群体生理指标及产量的影响

[目的]明确矮秆早熟高粱品种吉杂141在佳木斯地区的合理栽培密度。[方法]以吉杂141为研究对象,在大田生产试验条件下,采用平播的方式,设置15万、20万、25万、30万、35万株/hm2共5个栽培密度,研究不同栽培密度下,吉杂141的群体生理指标、产量及产量性状。[结果]随着栽培密度的增大,叶面积指数增加,叶绿素含量下降,群体光合势和总光合势增加,株高差异不显著,穗长、穗粗逐渐下降,生物产量上升,千粒重和单穗重下降。[结论]初步明确在佳木斯地区采用平播方式吉杂141最适栽培密度为20万株/hm2,产量可达9 203.36 kg/hm2。     

Enhancing pedotransfer functions with environmental data for estimating bulk density and effective cation exchange capacity in a data‐sparse situation

Soil bulk density (BD) and effective cation exchange capacity (ECEC) are among the most important soil properties required for crop growth and environmental management. This study aimed to explore the combination of soil and environmental data in developing pedotransfer functions (PTFs) for BD and ECEC. Multiple linear regression (MLR) and random forest model (RFM) were employed in developing PTFs using three different data sets: soil data (PTF‐1), environmental data (PTF‐2) and the combination of soil and environmental data (PTF‐3). In developing the PTFs, three depth increments were also considered: all depth, topsoil (<0.40 m) and subsoil (>0.40 m). Results showed that PTF‐3 (R²; 0.29–0.69) outperformed both PTF‐1 (R²; 0.11–0.18) and PTF‐2 (R²; 0.22–0.59) in BD estimation. However, for ECEC estimation, PTF‐3 (R²; 0.61–0.86) performed comparably as PTF‐1 (R²; 0.58–0.76) with both PTFs out‐performing PTF‐2 (R²; 0.30–0.71). Also, grouping of data into different soil depth increments improves the estimation of BD with PTFs (especially PTF‐2 and PTF‐3) performing better at subsoils than topsoils. Generally, the most important predictors of BD are sand, silt, elevation, rainfall, temperature for estimation at topsoil while EVI, elevation, temperature and clay are the most important BD predictors in the subsoil. Also, clay, sand, pH, rainfall and SOC are the most important predictors of ECEC in the topsoil while pH, sand, clay, temperature and rainfall are the most important predictors of ECEC in the subsoil. Findings are important for overcoming the challenges of building national soil databases for large‐scale modelling in most data‐sparse countries, especially in the sub‐Saharan Africa (SSA).     

水生动物肌醇营养研究进展

肌醇是大多数水生动物保持健康、促进生长发育必需的营养素,它在细胞膜磷脂合成、神经递质传递和肝脏脂质转运等方面发挥重要作用。饲料中肌醇缺乏导致水生动物生长不良、体表充血、鳍条糜烂、体色发黑、脂肪肝等症状。本文综述了肌醇的理化性质,肌醇在水生动物营养中营养生理作用、需要量及影响因素等,同时还介绍了肌醇的来源和测定方法,并展望了肌醇在水生动物营养中进一步的研究和应用方向。     

沙门菌CRISPR的结构与功能研究进展

近年发现沙门菌中恒定地存在两个CRISPR位点,沙门菌利用它们不仅能抵御外源质粒和噬菌体的入侵,还能介导自身短期的表型变化及长期亚类的进化。同时由于其结构的多样性,使之广泛应用于沙门菌分型和进化的研究。论文简要综述了沙门菌CRISPR系统的基本结构、作用机制和功能及其在沙门菌分型和进化应用方面的研究进展。     

穗期玉米昼夜生理状态规律的遥感综合探测研究

针对QY、PRI、NDVI、水势分别从不同的方面反映玉米的生理状况,以甜糯二号玉米作为材料,通过田间试验测量玉米昼夜4个参数值,研究了QY、PRI、NDVI、水势4个参数的昼夜变化,并且分析它们之间的相关性。结果表明,QY、水势、PRI三者具有很强的相关性,并且能建立回归模型表示它们之间的联系。     

Amplification,Sequence Analysis and Tissue Expression Detection of FUT2 Gene Coding Regions of Dongchuan Pigs

Porcine alpha (1,2) fucosyltransferase (FUT2) gene was importance in glycosphingolipid biosynthesis-globo series, potentially played a regulatory role during Escherichia coli (E. coli) F18 infection process in weaned piglets. In order to explore sequence structure of porcine FUT2 gene and its biological function, this test amplified FUT2 gene CDS sequence of Dongchuan pigs by PCR, forecasted and analyzed the protein sequences and functional regions of FUT2 gene, its expression level was detected in 11 tissues of 8 Dongchuan weaned piglets in 35 days old at the meantime. The results showed that the CDS sequence of FUT2 gene was 1 023 bp, which encoded 340 amino acids. FUT2 protein was fat-soluble hydrophilic protein, which the structure was not stable, including a transmembrane helix structure, but without signal peptide that suggested the FUT2 protein was a membrane protein;FUT2 protein included 2 N-glycosylation sites (No. 185 and No. 305 amino acids), without O-glycosylation sites, there were 14 potential phosphorylation sites, included 6 Ser, 2 Thr and 6 Tyr, analyzing the functional regions found that the FUT2 protein had a superfamily of conserved domains:FUT1-FUT2-like (58-319 amino acids). The phylogenetic tree result showed that the relative relationship between swine and cattle was relatively close, but was distant from chimpanzee, human, mouse and rat. FUT2 gene was expressed in all 11 tissues of Dongchuan weaned piglets, there were higher expression in digestive tract and immune tissues. The present results suggested that FUT2 gene might play a role to resistance to E. coli F18 in weaned piglets, and might indirectly against E. coli F18 through the synthesis of fucosyltransferase.     

绿豆品种资源萌发期耐碱性鉴定

采用人工气候箱内培养皿培养,以混合碱Na HCO3∶Na2CO3(摩尔比)为9∶1模拟典型东北地区碱胁迫环境,在萌发期以50 mmol L–1溶液处理34份绿豆品种资源,蒸馏水处理为对照,每培养皿放30粒种子。培养第3天测定发芽势,第7天测定发芽率、下胚轴长、胚根长、下胚轴干重、胚根干重等指标,通过隶属函数法和聚类分析对参试材料耐碱性综合评价,并进行因子分析。利用隶属函数法对参试材料耐碱性排序表明,不同绿豆品种资源间表现出较大差异,聚类分析把参试材料按耐碱性强弱分为4大类,白绿11等9份材料为耐碱类型,公绿1号等19份材料为耐碱中间类型,吉绿3号等5份材料为碱敏感类型,潍绿7号为碱极敏感类型。因子分析结果表明,萌发指数、下胚轴干重、胚根长分别在萌发因子、生物量累积因子和伸长因子中的负荷量最大,可作为绿豆萌发期耐碱性鉴定的适宜指标。     

Agronomic traits of soybean cultivars released in different decades after grafting record‐yield cultivar as rootstock

Breeders have seldom considered the selection for root traits during the genetic improvement in soybean. It is hypothesized that grain yield would be increased by the root function improvement, especially for the current cultivars. The objective of this grafting experiment was to determine the effect of record‐yield cultivars L14 or Z35 as rootstocks on agronomic traits of cultivars released in different decades. A total of 11 cultivars, released in different decades, were used to graft onto L14 or Z35 rootstocks. The agronomic traits were measured in the pot‐culture experiments. Grafting cultivars released in different decades onto L14 or Z35 rootstocks resulted in higher yield, 100‐seed mass and apparent harvest index as compared with those of non‐grafted or self‐grafted plants. Grain yield gain of cultivars grafted onto record‐yield cultivar rootstocks was 0.40 g/plant/year from 1966 to 2006, which was larger than that of non‐grafts and self‐grafts (0.27 g/plant/year). The yield of current cultivars should increase more if their root functions were improved.     

玉米籽粒早期发育相关蛋白的差异表达特性

玉米籽粒发育早期,代谢活动旺盛,细胞分裂与增大活跃,为后续贮藏物质的合成形成充足库容。为阐明籽粒早期发育的蛋白合成、积累与调控过程,本研究以夏玉米品种登海661为试验材料,在开花期人工饱和授粉后第3、第5、第10天取果穗中部籽粒,利用同位素标记相对定量(iTRAQ)技术分析其蛋白差异表达特性。玉米籽粒早期发育阶段总计鉴定及定量2639种蛋白,这些蛋白涉及多种生物过程与分子功能,其中代谢过程和分子过程是最主要的2个生物过程;催化活性和绑定功能是最主要的2个分子功能,这些生物过程与分子功能对籽粒早期发育具有重要作用。定量分析结果表明137种蛋白在籽粒发育早期显著差异表达,其功能涉及蛋白代谢、胁迫响应、细胞生长与分裂、碳水化合物与能量代谢、转运、次生物质代谢、淀粉合成、转录、油脂代谢、信号转导、氨基酸代谢等。其中,表达差异较大的是与蛋白代谢、胁迫响应、细胞生长与分裂以及碳水化合物与能量代谢相关的蛋白。表达模式聚类结果显示这些不同功能类别的蛋白协同表达,共同调控玉米籽粒的早期发育。     

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.