水稻ARF基因家族新成员ADP-Ribosylation Factor-Like Protein 5(OsARFL5)的克隆及表达分析

小G蛋白家族中的亚家族ADP-核糖基化因子(ADP-ribosylation factor, ARF),在生物体内起众多的生理作用,参与基因表达、细胞骨架重组装、微管的形成以及囊泡和核孔运输等。本研究已成功克隆得到ARF基因家族中的一个新基因OsARFL5,系统进化分析表明该基因与SiARFC1亲缘关系较近;以该基因和其启动子序列构建了两种遗传转化表达载体(pOsARFL5::GUS, pCaMV35S::OsARFL5:EGFP),并获得了相应遗传载体的转基因植株;GUS染色结果表明,该基因在不同时期、不同组织部位表达;洋葱表皮亚细胞定位结果显示,Os ARFL5基因编码的蛋白定位在细胞核。RT-PCR结果显示,OsARFL5在水稻不同生育期的根、茎、叶、叶鞘和穗子中均有不同程度的表达。本研究初步探明了ARF基因家族新成员OsARFL5在水稻生长发育过程中的表达模式。     

Regeneration in sugarcane via somatic embryogenesis and genomic instability in regenerated plants

In the present study, embryogenic calli of sugarcane variety BL4 were induced using 2,4-dichlorophenoxyacetic acid (2,4-D) and kinetin in different concentrations and combinations. In contrast to earlier studies, embryogenic callus sectors were identified and isolated microscopically within 1–2 weeks. Subsequently, 51 media formulations were used for regeneration of proliferated embryogenic callus, using MS medium supplemented with three different cytokinins [kinetin, 6-Benzylamino purine (BAP), and thidiazuron (TDZ)] and auxins (IAA/NAA and IBA) in different combination and concentrations. After acclimatization, the genomic DNA of regenerated plants was studied to explore the insertion polymorphism of transposable elements in order to ascertain the variation among somaclones. Though low concentration of kinetin with 2,4-D was found supportive to embryogenic callus development, the highest number of regenerated plantlets was observed using BAP (1 μM), however the plantlets had very low fresh weight (2.2 g). Conversely, TDZ alone supported a significant increase in the number of plantlets regenerated (38–40) with higher fresh weight. The somaclones generated during this study showed considerable positional polymorphism of activator-like transposable elements possibly due to the stress associated with in vitro culture. This study provides a procedure to produce regenerated sugarcane plants from embryogenic callus in a relatively short time.     

Comparison of protection and viral shedding following vaccination with Newcastle disease virus strains of different genotypes used in vaccine formulation

Tropical Animal Health and Production - Newcastle disease (ND) is a devastating disease and cause high t mortality and morbidity in poultry and nonpoultry avian species worldwide. An intensive...     

First detection and molecular characterization of avian polyomavirus in young parrots in Pakistan

Veterinary Research Communications - Avian polyomavirus (APV) infection, also called as budgerigar fledgling disease (BFD) causes various health problems in many psittacine species which may cause...     

小五台山亚高山草甸的群落特征及物种多样性

采用样带和样方相结合的方法沿海拔梯度取样,利用数量生态学方法对小五台山国家级自然保护区亚高山草甸群落进行分析。结果表明,1)双向指示种分析(TWINSPAN)将该区的草甸群落分为9个类型;2)RDA排序结果较好地反映出群落分布格局与环境梯度的关系,各个群落类型在前两轴分异明显;第一轴反映了群落分布格局与坡向、土壤温度、海拔、土壤厚度极显著相关(P0.01),与土壤湿度显著相关(P0.05);第二轴反映了群落分布格局与坡度、土壤厚度极显著相关(P0.01);3)环境因子的蒙特卡罗随机置换检验表明,坡向、海拔、坡度显著影响群落分布(P0.05),对植被类型的形成具有关键作用;4)草甸群落Patrick丰富度指数随着海拔的升高呈下降趋势,随着坡向值的增加、土壤温度的升高呈逐渐上升趋势;Shannon-Wiener多样性指数随土壤厚度的增大呈微小下降趋势;Pielou均匀度指数随着海拔的升高、土壤湿度的增大呈上升趋势,随着坡向值的增加、土壤温度的升高呈逐渐下降趋势;Simpson优势度指数随着坡度的增大表现出微小的下降趋势,随土壤厚度的增大呈上升趋势。     

大房郢水库浮游生物群落结构变化与环境因子关系研究

为了更好地了解合肥市饮用水源地水生态环境状况,于2020年夏季、秋季、冬季及2021年春季对大房郢水库的水质、浮游植物和浮游动物进行监测,对比浮游生物群落现存量与历史变化,并使用冗余分析（RDA）以及蒙特卡洛置换检验探究环境因子对浮游生物群落的影响。结果表明,研究区域浮游植物以蓝藻门为主要优势种属,密度及生物量较2005年分别增加37.7%和7.0%,浮游动物以桡足类为主要优势种,密度较2005年大幅度下降了77.5%,生物量多样性增加了47.8%,影响浮游生物群落结构的主要环境因子为NH3-N、T（温度）、pH和TN。此外,研究也揭示了季节变化对水库浮游生物的物种组成影响小,但对浮游生物的丰度及多样性影响显著。     

Guava (<Emphasis Type="Italic">Psidium guajava L</Emphasis>. cv. Red Suprema) Crude Extract Protect Human Dermal Fibroblasts against Cytotoxic Damage Mediated by Oxidative Stress

We analyzed guava fruits (Psidium guajava L. cv. Red Suprema) from Cuba to determine their chemical composition, total antioxidant capacity, as well as their protective effect against oxidative damage using an in vitro model of human dermal fibroblasts. The guava fruit is a natural source of bioactive compounds, such as polyphenols, vitamin C, folates and beta carotenes with proven health benefits. Human dermal fibroblasts were pre-incubated with different concentrations of guava crude extract and then subjected to oxidative stress using the AAPH stressor. The number of apoptotic and dead cells, as well as the markers of oxidative damage such as lipid and protein oxidation significantly decreased when cells were pre-incubated with guava crude extract and then exposed to the stressor. The activity of antioxidant enzymes also improved when cells were pre-incubated with guava crude extract in comparison to cells subjected to stress without prior pre-incubation with the guava extract. The results obtained in this study highlight the health benefits of guava regarding oxidative stress, proving it to be an important source of bioactive compounds associated with important biological properties.     

The changes in physiological and biochemical traits of Tibetan wild and cultivated barley in response to low phosphorus stress

Low phosphorus (LP) limits crop growth and productivity in the majority of arable lands worldwide. Here, we investigated the changes in physiological and biochemical traits of Tibetan wild barleys (Hordeum vulgare L. ssp. spontaneum) XZ99 (LP tolerant), XZ100 (LP sensitive), and cultivated barley ZD9 (moderately LP tolerant) under two phosphorus (P) levels during vegetative stage. These genotypes showed considerable differences in the change of biomass accumulation, root/shoot dry weight ratio, root morphology, organic acid secretion, carbohydrate metabolism, ATPase (Adenosine triphosphatase) activity, P concentration and accumulation under LP in comparison with CK (control) condition. The higher LP tolerance of XZ99 is associated with more developed roots, enhanced sucrose biosynthesis and hydrolysis of carbohydrate metabolism pathway, higher APase (Acid phosphatase) and ATPase activity, and more secretion of citrate and succinate in roots when plants are exposed to LP stress. The results prove the potential of Tibetan wild barley in developing barley cultivars with high tolerance to LP stress and understanding the mechanisms of LP tolerance in plants.     

Ascorbic Acid Enhances Growth and Yield of Sweet Peppers (Capsicum annum) by Mitigating Salinity Stress

Salinity is a crucial problem which has affected crop productivity globally. Ascorbic acid is considered helpful against abiotic stresses due to its powerful antioxidant potential. In the pot experiment, salinity stress (0, 35, 70, and 105?mM) was applied to sweet peppers in split doses after 20 days of transplantation. To mitigate the adverse effects of salinity, ascorbic acid (0, 0.40, 0.80, and 1.20?mM) was applied as foliar spray after a 6-day interval during vegetative growth. Sweet pepper plants sprayed with distilled water (control) recorded maximum plant height (cm), leaf area (cm²), number of branches, stem diameter (mm), number of fruit plant^?1, fruit diameter (cm), yield plant^?1 (g), and chlorophyll content (mg 100?g^?1), while the maximum polyphenol oxidase (PPO) activity (unit mg protein^?1 min^?1) and ascorbate peroxidase (APX) activity (unit mg protein^?1 min^?1) were recorded in plants treated with 70?mM NaCl application. Salinity stress beyond 70?mM significantly reduced all the studied parameters. An ascorbic acid concentration of 1.20?mM significantly mitigated the negative effects of salt stress and recorded maximum plant height (cm), number of leaves plant^?1, leaf area (cm²), number of branches plant^?1, stem diameter (mm), number of fruit plant^?1, fruit diameter (cm), yield plant^?1 (g), chlorophyll content (mg 100?g^?1), PPO activity (unit mg protein^?1 min^?1), and APX activity (unit mg protein^?1 min^?1). Hence, a 1.20?mM concentration of foliar ascorbic acid could be used in saline conditions up to 70?mM of sodium chloride (NaCl) for better growth, productivity, and enzymatic activity of sweet peppers.

     

Quality evaluation of different honey samples produced in Peshawar valley

The present study was designed to evaluate different honey samples obtained from local market for their quality parameters for assessment of their feasibility for foreign export by comparing it with international standards. The study was conducted at PCSIR laboratories complex, Peshawar, during 2006. The tested samples were evaluated for moisture content, Ash percentage, acid content, HMF and reducing sugars percentage. The moisture content of locally produced honey was in the range of 14.5 to 18.23%. The ash content of locally produced honey samples ranged between 0.047-0.35 which is within the standard limits. The acid content of the honey samples ranged between 19.5 and 38.0 meq kg(-1). The HMF contents of locally produced honeys ranged from 5.3 to 23.20 mg kg(-1). The content of reducing sugar of the tested samples ranged between 43.14 and 81.40% for the tested samples of locally produced honey. All of the samples were found to be in acceptable range of international standards for all of the tested parameters except for only one sample with lower reducing sugars. These samples were marked to be according to the international standards and are healthy for human consumption.