Detection of <Emphasis Type="Italic">Xanthomonas axonopodis</Emphasis> pv. <Emphasis Type="Italic">manihotis</Emphasis>, the causal agent of cassava bacterial blight diseases in cassava (<Emphasis Type="Italic">Manihot esculenta</Emphasis>) in Ghana by polymerase chain reaction

Xanthomonas axonopodis pv. manihotis (Xam) is the causal agent of cassava bacterial blight (CBB) disease. CBB is a major constraint to cassava cultivation in Ghana. In this study, a survey was conducted in eight regions of Ghana to assess the presence of CBB disease. Out of the eight regions visited, CBB, though at different prevalence, was observed in five regions. Cassava plants samples showing suspected bacterial blight symptoms were collected for analysis by Polymerase Chain Reaction (PCR). The results of the analysis showed that Ashanti region had the highest prevalence in percentage of CBB, which recorded (70%), followed by Volta region (60%); Brong Ahafo region (40%); Eastern region (40%) and Greater Accra region (20%). Morphological examination of the putative pathogen was carried out on Cefazolin trehalose agar (CTA) and Nutrient agar (NA) media. The isolates were subjected to conventional PCR using Xanthomonas genus specific primer, RST2/RST3, Xam specific Variable Number Tandem Repeat (VNTRs) loci, XaG1_67F/R and X-gumD primers, which produced 840, 446 and 402 bp, respectively. The isolates also tested positive with SYBR Green fluorescent dye, using Real-time PCR. The resulting PCR products were sequenced and analyzed using a BLASTn program, which revealed homology between 93 and 100% with several other Xam strains retrieved from GenBank nucleotide database. The pathogenicity test of the isolates on the susceptible Esam cassava variety produced symptoms typical of Xam and the pathogen was consistently re-isolated from the inoculated cassava plants and thereby satisfying the Koch’s postulates.     

复合酶制剂对伊犁鹅生产性能、血清生化指标及盲肠内容物代谢组的影响

本试验旨在研究饲粮中添加复合酶制剂(主要成分为蛋白酶、木聚糖酶、纤维素酶、甘露聚糖酶、α-淀粉酶和普罗兰酶)对伊犁鹅生产性能、血清生化指标及盲肠内容物代谢组的影响。试验选取健康状况良好、体重相近的4岁伊犁鹅200只,随机分为4组,每组10个重复,每个重复5只伊犁鹅(1公4母)。对照组饲喂玉米-豆粕型饲粮,试验Ⅰ、Ⅱ和Ⅲ组在对照组饲粮的基础上分别添加0.2、0.3和0.4 g/kg的复合酶制剂。预试期7 d,正试期38 d。结果显示:1)在生产性能方面,与对照组相比,试验Ⅱ组的产蛋率提高25.78%(P<0.05),料蛋比降低21.72%(P<0.05)。2)在血清生化指标方面,与对照组相比,试验Ⅱ组的总蛋白和球蛋白含量分别提高21.51%(P<0.05)、30.61%(P<0.05);试验Ⅰ、Ⅱ和Ⅲ组的谷草转氨酶活性分别提高69.85%(P<0.05)、41.26%(P<0.05)和49.02%(P<0.05),谷丙转氨酶活性分别提高34.78%(P<0.05)、33.78%(P<0.05)和40.80%(P<0.05);试验Ⅰ、Ⅱ和Ⅲ组的葡萄糖含量分别提高55.61%(P<0.01)、55.81%(P<0.01)和38.02%(P<0.01);试验Ⅱ组的总胆固醇含量降低15.97%(P<0.05);试验Ⅱ和Ⅲ组的低密度脂蛋白含量分别降低37.66%(P<0.05)和37.01%(P<0.05)。3)在盲肠内容物代谢组方面,对照组和复合酶制剂组(即试验Ⅱ组)共检测到5530种代谢物,筛选出21种差异代谢物,其中N-乙酰基-L-瓜氨酸、孕烯醇酮硫酸盐和L-瓜氨酸等12种代谢物的相对含量显著上调(P<0.05),N2-(D-1羧乙基)-L-赖氨酸、5-甲氧基吲哚乙酸酯和(R)-乳酸等9种代谢物的相对含量显著下调(P<0.05)。综上所述,在产蛋期伊犁鹅饲粮中添加0.3 g/kg复合酶制剂,可调控伊犁鹅血清中葡萄糖、总蛋白含量和蛋白质代谢相关酶活性,改善脂代谢能力,并可引起伊犁鹅体内21种代谢物及相关代谢途径发生显著变化,同时增强了伊犁鹅肠道的代谢活动,提高了营养物质利用率,从而提高了伊犁鹅的生产性能。     

Physicochemical and Microbiological Assessment of Ready-to-Eat Tuna Döner Kebab During Marination,Cooking, and Different Storage Conditions

ABSTRACT

The aim of this work was to investigate the use of bluefin tuna (Thunnus thynnus) in ready-to-eat döner kebab production and determine the effects of marination, cooking, and storage conditions (4 and ?18°C) on physicochemical and microbiological properties of döner kebab. The raw tuna meat and raw, cooked, and stored döner kebab samples were subjected to moisture, protein, fat, ash, pH, cholesterol, biogenic amines, lipid oxidation, fatty acids profile, microbiological, and sensory analysis. The major fatty acids in tuna döner kebab were palmitic, stearic, oleic, omega-3, and omega-6 fatty acids; unsaturated fatty acids were higher than saturated fatty acids (p < 0.05). Low biogenic amine and cholesterol contents were determined in döner kebab. While cooking affected the proximate composition, microbial load, and the levels of histamine and tyramine (p < 0.05), marination did not have any significant effect. The study results indicated that using tuna meat in döner kebab production could be an alternative approach to provide new seafood products without posing any acceptability problems in terms of quality factors.     

Identification and characterization of <Emphasis Type="Italic">Alternaria alternata</Emphasis> (Fr.) Keissler causing <Emphasis Type="Italic">Ceratonia</Emphasis> Blight disease of carob (<Emphasis Type="Italic">Ceratonia siliqua</Emphasis> L.) in Turkey

A new dagger nematode, Xiphinema tica n. sp., is described and illustrated from several populations extracted from soil associated with several crops and wild plants in Costa Rica. The new dagger nematode is characterised by a moderate body size (3276–4240 μm), a rounded lip region, ca 13.5 μm wide, separated from body contour by a shallow depression, amphidial fovea large, stirrup-shaped, a moderately long odontostyle ca 135 μm long, stylet guiding ring located at ca 122 μm from anterior end, vulva almost equatorial (50–54%), well-developed Z-organ, with heavy muscularised wall containing in the most of specimens observed two moderately refractive inclusions variable in shape (from round to star-shaped), with uterine spines and crystalloid bodies; female tail short, dorsally convex-conoid, with rounded end and a small peg, with a c’ ratio ca 0.8, bearing two or three pairs of caudal pores and male absent. The unique and novel uterine differentiation based on the coexistence of a well-developed Z-organ mixed with uterine spines and crystalloid bodies in Xiphinema prompted us to update and include this combination of characters in the polytomous key of Loof and Luc (1990). Integrative diagnosis was completed with molecular data obtained, using D2-D3 expansion segments of 28S rDNA, ITS1-rDNA, partial 18S–rDNA and the partial mitochondrial gene cytochrome c oxidase subunit 1 (coxI). The phylogenetic relationships of this species with other Xiphinema spp. indicated that X. tica n. sp. was monophyletic to the other species from the morphospecies Group 4, Xiphinema oleae.     

Prevalence of herbicide‐resistant weed species in Malaysian rice fields: A review

The management of weeds in Malaysian rice fields is very much herbicide‐based. The heavy reliance on herbicide for weed control by many rice‐growers arguably eventually has led to the development and evolution of herbicide‐resistant biotypes in Malaysian rice fields over the years. The continuous use of synthetic auxin (phenoxy group) herbicides and acetohydroxyacid synthase‐inhibiting herbicides to control rice weeds was consequential in leading to the emergence and prevalence of resistant weed biotypes. This review discusses the history and confirmed cases and incidence of herbicide‐resistant weeds in Malaysian rice fields. It also reviews the Clearfield Production System and its impact on the evolution of herbicide resistance among rice weed species and biotypes. This review also emphasizes the strategies and management options for herbicide‐resistant rice field weeds within the framework of herbicide‐based integrated weed management. These include the use of optimum tillage practices, certified clean seeds, increased crop competition through high seeding rates, crop rotation, the application of multiple modes of action of herbicides in annual rotations, tank mixtures and sequential applications to enable a broad spectrum of weed control, increase the selective control of noxious weed species in a field and help to delay the resistance evolution by reducing the selection pressure that is forced on those weed populations by a specific herbicidal mode of action.     

Solution electrospinning of polypropylene-based fibers and their application in catalysis

Since the dissolution of polyolefins is a chronic problem, melt processing has been tacitly accepted as an obligation. In this work, polypropylene (PP) was modified on molecular level incorporating poly(ethylene glycol) (PEG) as graft segment (PP-g-PEG) in a range of 6 to 9 mol%. Gold nanoparticles were nucleated in the presence of the copolymer chains via redox reaction. The dissolution of the amphiphilic comb-type graft copolymers containing gold nanoparticles (80 nm in diameter) was achieved in toluene and successfully electrospun from its solution. The diameter of composite fibers was in the range from 0.3 to 2.5 μm. The design of the structurally organized copolymer fiber mats provided a support medium for the nanoparticles enhancing the active surface area for the catalytic applications. The resulting composite fibers exhibited rapid catalytic reduction of methylene blue (MB) dye in the presence of sodium borohydride (NaBH₄) compared to corresponding composite cast film.     

松萝酸对AA肉仔鸡免疫器官生长发育的影响

为探讨松萝酸对肉仔鸡免疫器官生长发育的影响,试验选用225只1日龄AA肉仔鸡,随机分成5组,每组3个重复,每个重复15只.阴性对照组饲喂基础日粮,抗生素组添加0.3 g/kg那西肽和0.25 g/kg硫酸黏杆菌素预混剂,试验组分别添加0.003％、0.004％和0.005％松萝酸.结果表明,日粮中添加0.003％松萝酸对肉仔鸡1～42日龄体重及平均日增重具有一定的提高作用,但与其他组差异不显著(P＞0.05);添加0.004％松萝酸对肉仔鸡胸腺、法氏囊和脾脏的质量及指数均无显著影响(P＞().05),各添加组也均未观察到异常变化.从总体结果来看,日粮中添加0.004％松萝酸对肉仔鸡免疫器官的作用优于抗生素组.     

Influence of methionine and dithioerythritol on sperm motility, lipid peroxidation and antioxidant capacities during liquid storage of ram semen

The aim of this study was to investigate the effects of methionine and dithioerythritol, added to the Tris extender, on ram sperm motility and LPO (lipid peroxidation) and antioxidant capacities during liquid storage up to 72 h at 5 °C. Ejaculates collected from five Merino rams, were evaluated and pooled at 37 °C. This study included two experiments. In experiment 1, each pooled ejaculate was divided into four equal aliquots and diluted (37 °C) with the base extender, containing 0 (control), 1, 2 and 4 mM methionine, at a final concentration of approximately 4 × 10⁸ sperms/ml (single step dilution), in a 15-ml plastic centrifuge tube. In experiment 2, dithioerythritol, at concentrations of 0 (control), 0.5, 1 and 2 mM, was used as an additive in the extender, and the procedure explained above was applied for the division of aliquots and the dilution of semen. Diluted semen samples were kept in glass tubes and cooled from 37 to 5 °C in a cold cabinet, and maintained at 5 °C. Sperm motility and LPO and total glutathione (GSH) and glutathione peroxidase (GPx) capacities were determined at 5 °C for periods of 0, 24, 48 and 72 h of liquid storage.The extender supplemented with 1 mM methionine led to higher motility percentages (77.0 ± 1.2%), in comparison to the control group (66.0 ± 4.9%), during 72 h of liquid storage (P < 0.05). As regards dithioerythritol, it did not statistically improve the motility rates for any of the storage times at 5 °C. In biochemical assays, differences in LPO levels between the groups with antioxidants and the control groups were not statistically significant. Compared to the control group, no significant difference was observed in GSH and GPx activities following the addition of methionine, during 72 h of storage. Total GSH and GPx activities did not increase significantly upon supplementation with 0.5 and 1 mM of dithioerythritol, compared to the control group, at any of the time points (P > 0.05). Dithioerythritol at 2 mM led (P < 0.01) to elevating GSH activity, compared to the control group, during 72 h of liquid storage. GPx activity was approximately 10 times higher for 2 mM of dithioerythritol (P < 0.001), compared to that of the control group at all time points.The question regarding the sustainability of sperm survival, LPO and antioxidant capacities following liquid storage of semen remains unanswered. Further studies are required for a better understanding of the biochemical changes and to obtain more information on the determination of lipid peroxidation and antioxidant capacities during cooled storage of ram semen.     

Determination of growth performance,meat quality and colour attributes of large rainbow trout (Oncorhynchus mykiss) in the southern Black Sea coasts of Turkey

The aim of this study was to determine the growth performance, meat quality and colour attributes of large rainbow trout (Oncorhynchus mykiss) in net cage systems in the southern Black Sea coasts of Turkey. In the study, large rainbow trout with an initial weight of 1,322.07 ± 57.72 g were reached to 3,385.30 ± 140.98 g and the survival rates were 95.69 ± 1.32% in 5‐month production period. Crude protein and crude fat values of fish meat were ranged between 16.75 ± 0.07–20.18 ± 0.90% and 9.22 ± 0.15–12.29 ± 0.42%, respectively (p < .05). The essential and non‐essential amino acid values were between 12.92 ± 0.02–13.09 ± 0.01 g/100 g and 11.97 ± 0.14–11.47 ± 0.01 g/100 g, respectively (p > .05). C20:5n‐3, C22:6n‐3, ?3 and ?6 values in fish meat were between 4.32 ± 0.02–4.30 ± 0.08% (p < .05), 8.31 ± 0.10–7.72 ± 0.15% (p < .05), 13.41 ± 0.10–12.93 ± 0.23% (p < .05) and 21.85 ± 0.06%‐19.74 ± 0.36 (p < .05), respectively. As a result, it can be concluded that large rainbow trout cultured in the southern Black Sea coasts of Turkey is a rich source of food in terms of fatty and amino acid compositions and atherogenicity index, thrombogenicity index and hypocholesterolaemic/hypercholesterolaemic values.