Effect of exogenously added ferulic acid on in vitroFusarium oxysporum f. sp. niveum

Allelochemicals from root exudates or decaying residues of watermelon plant may be related to watermelon fusarium wilt. The aim of this work was to study the effect of an artificially applied allelochemical, ferulic acid, on in vitroFusarium oxysporum f. sp. niveum (FON), a causal pathogen of plant wilting in the laboratory setting.     

Cinnamic acid inhibits growth but stimulates production of pathogenesis factors by in vitro cultures of Fusarium oxysporum f.sp. niveum

Long-term monoculture of watermelon leads to frequent occurrence of watermelon fusarium wilt caused by Fusarium oxysporum f.sp. niveum (FON). Some allelochemicals contained in watermelon root exudates and decaying residues are possibly responsible for promoting the wilt disease. The purpose of this study was to evaluate the allelopathic effect of artificially applied cinnamic acid on FON. Results demonstrated that hyphal growth of FON was strongly inhibited by cinnamic acid. At the highest concentration of cinnamic acid, the biomass in liquid culture was decreased by 63.3%, while colony diameter, conidial germination on plates, and conidial production in liquid culture were completely inhibited. However, mycotoxin production and activity of phytopathogenic enzymes were greatly stimulated. Mycotoxin yield, pectinase activity, proteinase activity, cellulase activity, and amylase activity were increased by 490, 590, 760, 2006, and 27.0%, respectively. It was concluded that cinnamic acid dramatically stimulated mycotoxin production and activities of hydrolytic enzymes by FON but inhibited growth and germination of FON. The findings presented here indicate that cinnamic acid is involved in promoting watermelon fusarium wilt.     

Effects of Haloxylon spp. of Different Age Classes on Vegetation Cover and Soil Properties on an Arid Desert Steppe in Iran

In arid regions, afforestation has been considered as a method for ecological revival in terms of vegetation enrichment and soil amelioration. In this study, the effects of afforestation with Haloxylon spp. on vegetation cover and soil properties were measured < 3, 3, 6, and 25 years after planting in an arid desert in Iran. Soil samples were collected at two depths (0-30 and 30-60 cm) under and between shrub canopies. Afforestation succession significantly affected plant community characteristics. In total, 16 species from 8 families and 15 genera were observed along the afforestation successional gradient. Plant species richness and diversity and vegetation cover increased slowly during the succession, and reached the maximum values in the area where Haloxylon had been planted for 25 years. Soil nutrient values gradually increased during the succession, and the levels of organic matter, total nitrogen, available potassium, and available phosphorus were significantly higher under Haloxylon canopies than between them. Afforestation reduced soil pH under and between Haloxylon canopies during the succession, while soil electrical conductivity followed an opposite pattern. Haloxylon planting increased the silt content in the 0-30 cm soil layer. Our results suggest that Haloxylon establishment plays an important role in the reestablishment of desertified ecosystems in arid regions.     

Colonization and nitrogenase activity of Triticum aestivum (cv. Baccross and Mahdavi) to the dual inoculation with Azospirillum brasilense and Rhizobium meliloti plus 2,4-D

The potential enhancement of root colonization and nitrogenase activity of wheat cultivars (Baccross and Mahdavi) was studied with application of two Azospirillum brasilense strains (native and Sp7) co-inoculated with two Rhizobium meliloti strains (native and DSMZ 30135). The results indicated that the colonization was different due to the strains and cultivars of wheat were used. Native A. brasilense colonized wheat root better than Sp7 strain. However, Baccross cv. reacted better with native Azospirillum compared to Mahdavi cv. which reacted better with Sp7. When plants inoculated with dual inoculants (SP7 with standard Rhizobium), the colonization of Azospirillum were increased significantly (from 1.67 x 10(5) to 22 x 10(5) cfu g(-1) FW for Baccras cv. and 3.67 x 10(5) to 26 x 10(5) cfu g(-1) FW for Mahdavi cultivar). When the standard Rhizobium as co-inoculants changed to the native Rhizobium, the colonization of Azospirillum was higher when compared to the single inoculants but was almost the same when compared to the standard Rhizobium. When the standard or native strains of Rhizobium used as single inoculation of wheat roots, the number of Rhizobium in the wheat roots were not changed significantly. However, when plants co-inoculated with Rhizobium and Azospirillum, the colonization of Rhizobium was increased. Co-inoculation of standard strain of R. melilot with A. brasilense Sp7 showed that the colonization of Rhizobium were increased from 0.67 x 10(5) to 21 x 10(5) cfu g(-1) FW for Baccross cv. and 0.33 x 10(5) to 18 x 10(5) cfu g(-1) FW for Mahdavi cv. This behavior was the same when inoculation of Rhizobium was happened with the native one. In dual inoculation, the highest nitrogenase activity was measured in combination of the local strains (native A. brasilense with the native R. meliloti) and the lower one belongs to the combination of standard strains (Sp7 with standard R. meliloti). The difference in nirtogenase activity for different cultivars of wheat with Sp7 and standard Rhizobium is not significant but the difference for Sp7 strain plus native Rhizobium is significant (p > 0.05). However, the differences were not significant (p < 0.05) for nitrogenase activity in bacterial tubes, the difference for nitrogenase activity of co-inoculated plants with combination of Sp7 and Rhizobium either standard or native were significantly different.     

Is cooking food in iron pots an appropriate solution for the control of anaemia in developing countries? A randomised clinical trial in Benin

OBJECTIVE: To evaluate the effect of two types of iron pots on haemoglobin (Hb) and serum ferritin (SF) concentrations in young children (6-24 months), adolescent girls (11-15 years) and women of reproductive age (15-44 years), whose households were provided with iron pots for cooking food over a period of 6 months, compared with controls.Design and methodsWe randomly assigned 161 households including 339 individuals from the three subgroups to cast iron pots, blue steel pots or oral iron supplements (control). In the control group, children received micronutrient Sprinklestrade mark, and adolescent girls and women received iron tablets daily for 6 months. We measured Hb, SF and C-reactive protein concentrations at baseline and 6 months, and compared groups using regression models. RESULTS: Anaemia prevalence (Hb < 110 g l-1 in infants, Hb < 120 g l-1 in girls or women) was 47% (cast iron group), 50% (blue steel group) and 50% (control) at baseline. At 6 months, there were no significant differences in Hb concentrations among groups; however, differences in SF concentrations were significant (P < 0.0001) - the control group had higher SF concentrations compared with the groups using iron pots. Also, differences in the prevalence of iron-deficiency anaemia (IDA; anaemia plus SF < 15 mug l-1) were almost significant between cast iron and control groups (P = 0.08), and blue steel and control groups (P = 0.05).ConclusionThere is no evidence that iron cooking pots are effective against IDA. Further research is warranted to determine whether the iron leached from the pots is bioavailable.     

Optimal isotherm model and explanatory characteristics associated with metal ion adsorption on humic acids isolated from forest soils

Journal of Soils and Sediments - Understanding the mechanisms of interaction between humic acids (HAs) and metal ions in soil media is essential for integrated environmental and agricultural...     

Preparation of extract-loaded nanocapsules from Onopordon leptolepis DC.

Sesquiterpenes have antifungal, antibacterial, and anesthetic properties. It is also thought that they prevent migraines and can be used as antibiotics and to treat malaria, but there are very few in-depth testing results available to support these claims. Nanocapsules coated by medicinal plants have many applications in drug manufacturing. Medicinal plants can be loaded on nanocapsules with the polyester triblock copolymer polyethylene glycol-polybutylene adipate-polyethylene glycol (PEG-PBA-PEG) as the shell and olive oil as the core by a process known as the polymer deposition solvent evaporation method. It has been shown that the size of nanocapsules depends on a variety of factors, such as the ratio of polymer to oil, concentration of polymers, and concentration of plant extract. In this research we attempted to prepare nanocapsules by emulsification of a mixture of onopordopicrin extracted from Onopordon leptolepis DC., polymer, acetone, and olive oil in aqueous phase without using surfactant. The nanocapsules were characterized by scanning electron microscopy and zeta potential sizer.     

Assessment of drought tolerance in mung bean cultivars/lines as depicted by the activities of germination enzymes,seedling’s antioxidative potential and nutrient acquisition

Drought stress hampers firm crop stand establishment and yield in arid and semiarid regions. The present study was conducted to examine the drought tolerance of various mung bean cultivars/lines based on the seed germination characteristics in relation with the seedling’s antioxidative potential and nutrient uptake. Activities of germination enzymes, seed germination attributes, seedling biomass production and nutrient uptake of studied cultivars/lines were adversely affected due to PEG-induced drought but the total soluble proteins (TSP) and malondialdehyde (MDA) contents were increased. The activities of catalse (CAT) and ascorbate peroxidase (APX) increased in all cultivars/lines being the maximum in cv./line NM-2006 and 8005. The activities of superoxide dismutase (SOD) and peroxidase (POD) were increased in cv./line NM-2006 and 8005 under drought condition. The ascorbic acid (AsA) and total phenolic content (TPC) decreased and total flavonoid content (TFC) increased in all cultivars/lines due to drought. Significant reduction in N, P, K, Ca and Mg was found in all cvs./lines but Fe remain unchanged. In conclusion, cultivars/lines NM-2006, 8005 were recommended as drought tolerant and 97,006 and 97,001 as drought sensitive ones. The study outcomes will likely be helpful for the farmers growing mung bean in rain fed areas for the better productivity.     

白斑狗鱼StAR基因克隆及其表达分析

【目的】克隆白斑狗鱼（Esox lucius）类固醇激素合成急性调节蛋白（StAR）基因（ElStAR）并分析其组织表达差异,为开展StAR基因生物学功能研究及揭示白斑狗鱼性腺发育机制提供基础资料。【方法】根据GenBank已公布的白斑狗鱼基因组测序结果（NC_047581.1）设计特异性引物,采用RT-PCR克隆ElStAR基因cDNA序列,通过ClustalX、ExPASy、TargetP 1.1、TMHMM 2.0和SignalP 5.0等在线软件进行生物信息学分析,并采用实时荧光定量PCR进行ElStAR基因组织表达定量分析。【结果】ElStAR基因cDNA序列长度1485 bp,其开放阅读框（ORF）为864 bp,共编码287个氨基酸残基;ElStAR氨基酸序列与北极红点鲑StAR氨基酸序列的相似性最高（93.33%）,与海鳟、条纹鲈鱼、金头鲷、大菱鲆、斑马鱼、半滑舌鳎的相似性均高于75.00%,而与小家鼠的相似性最低（59.15%）;基于StAR氨基酸序列相似性构建的系统发育进化树也显示白斑狗鱼与北极红点鲑和海鳟等鲑科鱼类处于同一分支。ElStAR蛋白相对分子量为32.23 kD,理论等电点（pI）为8.98,为不稳定的亲水性蛋白;具有START结构域,无信号肽及跨膜结构,符合线粒体靶向肽的基本特征。ElStAR蛋白二级结构由α-螺旋（占40.77%）、无规则卷曲（占35.89%）、延伸链（占18.12%）和β-折叠（占5.23%）组成,其三级结构是由α-螺旋配合多个β-折叠卷曲盘旋而成。ElStAR基因在白斑狗鱼精巢、卵巢、头肾、肝脏、肌肉及脑组织中均有不同程度的表达,且在精巢中的相对表达量极显著高于在卵巢中的相对表达量（P<0.01）,呈明显的性别二态性表达模式。【结论】ElStAR基因编码蛋白结构和功能十分保守,具有典型的START结构域,对胆固醇的运输和调节起重要作用。ElStAR基因在白斑狗鱼精巢及卵巢中的表达存在极显著差异,可能在维持白斑狗鱼精巢的发育形成中发挥重要作用。     

Comparison of three models describing bromide transport affected by different soil structure types

This study was conducted to investigate the effects of soil structure on bromide (Br) transport through three soils with granular, prismatic, and single-grain structures. The breakthrough curve (BTC) of the single-grain structure was sigmoidal, symmetrical and similar to a piston flow, showing the dominance of mass flow. In contrast, the BTCs of the granular and prismatic structures were initially steep, becoming more gradual at high pore volumes (PVs). The stable structure and preferential pathways caused the early breakthrough of Br in the leachate of these columns. The convection–dispersion equation (CDE), mobile–immobile water (MIM), and dual-permeability (DP) models were fitted to observed data using the program HYDRUS-1D. The equilibrium transport model (CDE) was not as successful as non-equilibrium (MIM and DP) models in describing the Br transport in prismatic and granular soil columns, although it was able to describe the Br transport in single-grain column well. Overall, the results demonstrated the importance of soil structure in pollutant transport through soils.