酒酒球菌SD-2a原生质体制备条件研究

通过对预处理剂质量浓度、酶质量浓度、酶解时间、菌龄等影响因素的分析,以及渗透压稳定剂的筛选,对酒酒球菌SD-2a原生质体的制备条件进行了研究。结果表明,酒酒球菌SD-2a原生质体制备的最佳条件为:菌龄20 h,青霉素G钠质量浓度0.5μg/mL,酶质量浓度1mg/mL,酶解时间30 min,渗透压稳定剂采用SMM缓冲液,再生培养基采用添加0.7 mol/LKCl的ATB培养基,再生培养时采用双层培养基厌氧培养,可以保证较好的形成率和再生率。     

用苹果酸通透酶基因的特异性引物进行酒酒球菌快速鉴定

以Oenococcus oeni苹果酸通透酶基因为目标基因,设计了1对特异性引物PmlepL/PmlepR进行酒酒球菌的快速鉴定研究。结果表明,直接以O.oeni的菌落为模板,通过PmlepL/PmlepR引物的PCR扩增,可得到苹果酸通透酶基因的特异性条带;用此特异性引物进行供试乳酸菌的PCR鉴定,所有O.oeni菌系均得到特异性条带,而供试的其他种类乳酸菌未扩增出目标带。引物PmlepL/PmlepR可用于O.oeni的快速PCR鉴定。     

The Effect of Acid Stress Treatment on Viability and Membrane Fatty Acid Composition of Oenococcus oeni SD-2a

To obtain ready-to-use wine malolactic starter cultures with high viability, the effects of acid stress treatments on the growth, inoculation viability, freeze-drying viability, and membrane fatty acid composition of the native Oenococcus oeni SD-2a strain were studied. The results showed that pH 3.5 and 3.2 adaptive treatments did not strongly decrease cell biomass but increased distinctly inoculation viability and freeze-drying viability. Concerning the membrane fatty acid composition, it was observed that acid stress conditions increased significantly the relative concentration of lactobacillic acid （C19cycl 1） and the unsaturated：saturated fatty acid ratio in cell membrane lipids. We assumed that acid-induced cross protective responses could be used in preparing ready-to-use O. oeni SD-2a malolactic starter cultures, and the accumulation of lactobacillic acid in the membrane of O. oeni SD-2a cells appears as an acid stress response mechanism, which might be related with the enhanced viability.     

mleA基因在酿酒酵母中的整合型表达

 【目的】进行中国自行筛选的专利菌种酒酒球菌 SD-2a（Oenococcus oeni SD-2a）的苹果酸－乳酸酶基因在酿酒酵母中的整合型表达,使葡萄酒生产过程中的酒精发酵和苹果酸－乳酸发酵（malolactic fermentation,MLF）同时进行。【方法】克隆Oenococcus oeni SD-2a的苹果酸－乳酸酶基因mleA,以PGK1强启动子和ADH1终止子为调控元件,以酵母整合型质粒YIp5为载体,构建重组表达质粒pYILmleA,并转化酿酒酵母（Saccharomyces cerevisiae）YS59,经筛选鉴定获得酵母转化子YS59/pYILmleA。进行转化子的营养缺陷型和交配型鉴定、菌落PCR鉴定、SDS-PAGE检测及斑点杂交检测,并对酵母转化子培养上清液进行L-苹果酸及L-乳酸含量的HPLC分析,检测目的基因的功能性表达。【结果】转化子的营养缺陷型和交配型鉴定、菌落PCR鉴定表明获得了阳性转化子;SDS-PAGE检测表明获得的转化子表达了目标蛋白,斑点杂交检测表明目的基因整合到受体菌中。模拟发酵表明mleA基因整合到受体菌中后进行了功能性表达,将培养基中的L-苹果酸转化成L-乳酸,使得培养液中的L-苹果酸含量极显著降低。转化子YS59/pYILmleA在添加5 648 mg?L-1 L-苹果酸和10%葡萄糖的SD/-Ura培养基中培养4 d,培养液上清中L-苹果酸的剩余含量与空载体转化子YS59/YIp5（对照）差异极显著,苹果酸的相对降低率为20.18%～20.85%。供试的转化子L-乳酸生成量为1 278～1 312 mg?L-1,对照未检出乳酸的生成。【结论】中国自主筛选的专利菌种O.oeni SD-2a的mleA基因的整合型表达质粒构建成功并在酿酒酵母中进行了功能性表达。     

酒酒球菌膜脂肪酸成分分析的样品处理方法比较

为筛选较适合的酒酒球菌膜脂肪酸提取和皂化方法,采用5种不同脂肪酸分析样品前处理方法,结合气相色谱质谱联用仪(GC/MS),分析酒酒球菌SD-2a膜脂肪酸成分,比较不同处理方法的效果。结果表明,先提取脂肪酸再采用NaOCH3甲酯化脂肪酸的方法能够较为准确和完整地检出酒酒球菌SD-2a的12种膜脂肪酸,相对标准误差(RSD)≤5%,特别对于环丙烷脂肪酸的检测效果较好,RSD=2%;独立的脂肪酸提取步骤对细菌膜脂肪酸分析是必要的,包含脂肪酸提取的样品处理方法比不包含脂肪酸提取的方法多检出3种脂肪酸,RSD均≤5%。     

Effects of Elemental Sulphur and Farmyard Manure on pH and Salinity of Calcareous Sandy Loam Soil and Some Nutrient Elements in Tomato Plant

The objective of this study was to evaluate the effects of elemental sulphur （S） and farmyard manure on soil pH, EC and N, S, P concentrations of tomato grown in a calcareous sandy loam soil. For this purpose, a pot experiment was conducted in greenhouse conditions. Sulphur was applied at 0, 50, 100, 150, 200, 400 mg kg~ and farmyard manure at 0, 3 ton da^-1 to the soil. Three weeks after applications, tomato seedlings were planted and 8 weeks later, the plants were harvested to determine N, S, P concentrations and dry matter yield. Soil pH and EC were determined in the soil samples taken at 3 different periods. Effects of sulphur and farmyard manure applications were not significant on N, P concentrations and dry matter yield of tomato plant. S concentration of tomato plant was increased by sulphur alone. Soil pH was decreased and soil EC was increased in both 2^nd and 3^rd soil sampling period by the sulphur applications. As a result of farmyard manure application, soil pH decreased in the 2^nd soil sampling period but increased in the 3^rd soil sampling period. Also, soil EC was significantly increased in 1^st and 3^rd soil sampling period. Farmyard manure had no significant effect on S supply to tomato plant. The N：S ratio of tomato plant was decreased by sulphur alone. However, the sulphur with farmyard manure applications decreased N：S ratio in lesser extend compared to the S applications.     

Cooking Quality Parameters of Rice Cultivars Grown in Spain

The quality office is complex and made up of many components such as nutritional quality, appearance, cooking quality and eating quality. The cultivar is one of the main factors that could affect to the grain quality office. The aim of this work was to analyze and compare the cooking quality parameters of six different japonica varieties of rice grown in Spain （Senia, Gleva, Bahia, Maratelli, Guadiamar and Bomba）. This work focused on the study of the cooking quality of rice, because it is one of the most important factors related to grain quality in Spain. It was evaluated using five characteristics： amylose content, gel consistency, degree of spreading, gelatinization temperature and pasting parameters. The amylose content ranged from 11.60% to 21.46%, with the Gleva cultivar having the lowest amylose content and with Bomba having the highest. The gel consistency varied between 5.44 cm and 9.81 cm. Regarding the alkali test, the Maratelli cultivar had the highest dispersion and transparency. Maratelli had the lowest gelatinization temperature （61.67±0.08 ℃）, and Senia had the highest gelatinization temperature （67.05±0.02 ℃）. Finally, the pasting parameters showed significant differences among cultivars with different viscosities.     

Interactive Effects of Elevated CO2 and Temperature on Rice Planthopper,Nilaparvata lugens

It is predicted that the current atmospheric CO2 concentration will be doubled and global mean temperature will increase by 1.5-6＆#176;C by the end of this century. Although a number of studies have addressed the separate effects of CO2 and temperature on plant-insect interactions, few have concerned with their combined impacts. In the current study, a factorial experiment was carried out to examine the effect of a doubling CO2 concentration and a 3℃ temperature increase on a complete generation of the brown planthopper （Nilaparvata lugens） on rice （Oryza sativa）. Both elevated CO2 and temperature increased rice stem height and biomass of stem parts. Leaf chlorophyll content increased under elevated CO2, but only in ambient temperature treatment. Water content of stem parts was reduced under elevated temperature, but only when coupled with elevated CO2. Elevated CO2 alone increased biomass of root and elevated temperature alone enhanced leaf area and reduced ratio of root to stem parts. Brown planthopper （BPH） nymphal development was accelerated, and weight of and honeydew excretion by the F1 adults was reduced under elevated temperature only. Longevity of brachypterous females was affected by a signiifcant interaction between CO2 and temperature. At elevated temperature, CO2 had no effect on female longevity, but at ambient temperature, the females lived shorter under elevated CO2. Female fecundity was higher at elevated than at ambient temperature and higher at elevated CO2 than at ambient CO2. These results indicate that the combined effects of elevated temperature and CO2 may enhance the brown planthopper population size.     

Absorption of Food in African Pike Hepsetus odoe （Bloch, 1974） in Ado Ekiti Reservoir,Ekiti State,Southwestern Nigeria

The protein, carbohydrate and lipid contents of the food ingested and their absorption in the intestine ofHepsetus odoe in Ado-Ekiti Reservoir, Ekiti State, Nigeria were investigated. Samples were analysed chemically for protein, fat and carbohydrate using the official methods of analysis described by the Association of Official Analytical Chemist. The ingested food had mean total protein, mean total carbohydrate and mean total lipid of 60.2% - 8.55%, 15.4% ± 1.9% and 15.6% ±1.1% of the organic content respectively. Calculated mean total percentages absorbed were 72.4% protein, 52% carbohydrate and 51.5% lipid. The foregut had the highest percentage absorption while the hindgut had the lowest for all the nutrients. Different sizes of fish showed different dietary protein, carbohydrate and lipid contents. Absorptive capacity for these components of the food also varied with fish size.     

Mechanical Properties of Sunflower Seed and Its Kernel,Azargol Variety as a Case Study,under Compressive Loading

The objective of this study was to investigate the effect of moisture content, size and loading orientation on mechanical properties such as force, deformation and energy absorbed per unit volume for fracturing Iranian sunflower seed and its kernel （Azargol as a case study） under quasi-static loading. Sunflower seeds and their kernels were quasi-statically loaded in horizontal and vertical orientations with moisture content in three levels： 3%, 7% and 14%, and size category in three levels： small, medium and large. The obtained results showed that rupture force for both sunflower seed and its kernel decreased with increasing moisture content while the absorbed energy and deformation at rupture point increased for all size categories in both horizontal and vertical loading orientations. Also, seeds in the vertical orientation developed hull cracks at a higher level of force than those loaded in the horizontal orientation. However, for the kernels it was the opposite. In addition, the average forces required to cause kernel rupture were lower （11.64-39.9 N） than those required to rupture the seed （30.06-117.46 N） in both orientations. Seeds loaded in a vertical orientation absorbed more energy （87.67 mJ） prior to rupture than those loaded in the horizontal （46.60 mJ） orientation. However, for the kernels it was the opposite.     

Some Engineering Properties of Sunflower Seed and Its Kernel

Some engineering properties of sunflower seed and its kernel, Shahroodi variety as a case study, were investigated at various moisture content levels （3-14% d.b.） for three size categories （large, medium and small）. With increase of moisture content from 3 to 14% d.b., all the main dimensions （length, width and thickness）, geometric mean diameter, porosity, true density, terminal velocity and static coefficient of friction increased while bulk density and rupture force for both sunflower seed and its kernel decreased for all size categories. The results showed that the highest value of static coefficient of friction for both seed and kernel was on the rubber surface, followed by plywood, polyethylene, galvanized iron, and finally aluminium surfaces. The seeds required less compressive force to dehull when loaded under the horizontal as compared to the vertical orientation. But for kernels, the trend was the opposite. Also, the compressive forces needed to initiate rupture of sunflower seed hulls were higher （47.1-94.72 N） than those required to rupture the kernel （8.5-13.4 N） in both orientations.     

Modelling Agronomically-Suitable Sowing Date in Relation to the Risk of Frost Damage and Heat Stress of Wheat in Southern New South Wales,Australia

Sowing time of wheat in south eastern Australia varies from autumn to early winter, depending on the seasonal ＇break＇. Wheat yields are often reduced by frost damage at flowering time and by heat-and/or water-stress during grain filling. Selecting suitable varieties for specific sowing times is a complex decision farmers make because these varietal phenology and climate risks have to be assessed together. In order to help farmers make decisions, they need tools that simulate and analyse agronomically-suitable sowing dates （ASSD） for a given variety of wheat. The hypothesis underlining this study is the integration of a wheat phenology model with historical climate data is an effective approach to modelling the ASSD of current varieties used in the wheat growing areas of Southern NSW. The parameters of the wheat phenology model were based on data from five years of field experimentation across 15 sites. Data from four sites were used to examine varietal suitability in relation to sowing time and its associated risks of frost and heat damage. The optimum ASSD for any variety at 72 locations across Southern NSW was investigated. The results showed that there were substantial spatial variations in the ASSD across the target region. ASSD for a late maturing wheat genotype （EGA Gregory） can range from early March to late April, while the earliest acceptable sowing date for an early maturing spring wheat genotype （H46） can range from early to late May. The wide range of spatial variation in the earliest and latest sowing dates, as well as the varied length of sowing opportunities, highlighted the importance of being able to apply a modelling approach which can integrate information on crop phenology with climate risk for a given location. This approach would allow better decision-making on suitable varieties and sowing dates in order to minimise the risk of frost and heat damage affecting crop yield.     

Under-Winter Sowings of Red Beetroot in Uzbekistan

The results of the three-year researches which had the purpose to establish an optimum depth of seeding at sowing and rational norm of seeding of red beetroot seeds at under-winter sowing in conditions of mid-loamy typical grey soils of the central climatic zone of Uzbekistan are stated in article. The researches were spent at statement of field experiences in quadruple frequency with the area of a registration allotment 10 M^-1. Crops were carried out in the first decade of December against mulching surfaces of ridges by humus and without mulching. Crops were carried out on ridges in width of 70 sm tape-two-lined with distance between tapes of 50 sm, between lines-20 sm and distance between plants in a line of 12-13 sm, at density of standing of 228-230 thousand plants/hectares. Experiences were spent with zoned in Uzbekistan multi-seedling grade of a red beetroot ＂Bordo 237＂. Experiences were accompanied by phenological supervision, biometric accounts, the account of field germination of seeds, density of standing of plants and definition of size and quality of a crop. Results of researches were exposed to the statistical analysis by a dispersive method. It has been revealed that at under-winter sowing of a red beetroot the effective way providing acceleration of shoots occurrence, formations of high-grade density of standing and increase of productivity of root crops is mulching the surfaces of ridges by humus. It is defined that optimum depth of seeding at sowing both at application of mulching and without it is the depth of seeding 4 sm. It is established that the most rational norm of seeding of the seeds, providing high-grade density of standing, is at cultivation with application of mulching 8 kg/ha, and at cultivation without mulching 8-10 kg/ha. Application of mulching the surfaces of ridges by humus, depths of seeding of 4 sm and norms of seeding of seeds of 8-10 kg/ha in conditions of under-winter sowing in comparison with cultivation without mulching and depth of seeding 2 sm and norms of seeding of 6 kg/ha provides an acceleration of receipt of fresh production of a red beetroot for 12-14 days and considerably raises root crops productivity. Application of agro receptions improved by us is the important reserve of acceleration of receipt of red beetroot early production and increase of its manufacture.     

Early Stage above Ground Interaction in Wheat-Jatropha Agrisilviculture System

Experiments were conducted to analyze the initial tree crop interaction between Jatropha curcas and wheat by planting the perennial component in East-West orientation with 8-2 m distance and wheat as intercrop at National Research Centre for Agroforestry （NRCAF）, Jhansi during July, 2007 to April, 2009. During planting of Jatropha the interaction to wheat was non-significant and influence of orientation is also nil. Eighteen months after plating Jatropha had attained the mean height of 124.56 cm, collar diameter of 6.37 cm, number of branches of 11.25, canopy diameter of 98.5 cm and yielded 18.5 g seeds per plant. During 18 MAP also observations revealed the non-significant influence of Jatropha on wheat. Observations also indicated the progress in wheat growth and yield attributes with the increase of distances from tree base and it follow the order of 0.5 m〈1.0 m〈2.0 m〈3.0, 4.0 m and open. Nearly, 62% and 14% yield loss in wheat grain was observed at 0.5 m and lm distance from the tree base respectively compare with open. Comparison ofwheat-Jatropha agrisilviculture system and sole wheat cropping indicated the net grain yield reduction up to 13.5% by agrisilviculture system. The comparison of wheat and straw yields between the two years clearly indicating that the system and sole cropping have not much differed while the influence of climatic factor is witnessed by the variation of yields over years. It revealed that the initial above ground interaction between Jatropha and wheat was due to the space that can be managed by the pruning of branches which is a recommended cultural practice of Jatropha.     

Microbial Solubilization of Phosphorus from Nano Rock Phosphate

Phosphorus （P） is a major growth-limiting nutrient, and unlike the case of nitrogen （N）, there is no large atmospheric source that can be made biologically available. Moreover, P governs crucial role in plant as it stimulates root development and growth, gives plant rapid and vigorous start leading to better tillering and essential for many metabolic processes for seed formation. Soil microbes play very important role in bio-weathering and biodegradation. The microorganisms produce low molecular mass organic acids, which attack the phosphate structure and transform phosphorus from non-utilizable to the utilizable for the plants form. The test of the relative efficiency of isolated strains is carried out by selecting the microorganisms that are capable of producing a halo/clear zone on a plate owing to the production of organic acids into the surrounding medium. It is a well-known fact that as the particle size of rock phosphate decreases, the microbe mediated solubilization of rock phosphate increases in soil. In the present investigation, microbial solubilization of nano rock phosphate （〈 100 nm） particles was studied. Experimental results revealed that Pseudomonas striata solubilized 11.45% of the total P after 24 h of incubation from nano rock phosphate particles while 28.95% and 21.19% of the total P was solubilized by Aspergillus niger （black pigmented） and Aspergillus niger （green pigmented）, respectively. It was also observed that Aspergillus niger has the higher ability to dissolve Udaipur rock phosphate than Pseudomonas striata.     

Analysis of Oleanolic Acid and Ursolic Acid,Potential Antifertility Agents in Moringa （Moringa oleifera） Seed

Oleanolic acid （OA） and ursolic acid （UA） are isomeric tritcrpenes that are difficult to separate chromatographically. Studies have indicated that both OA and UA have antifertility properties in several livestock species, suppressing attainment of puberty, gonad function and gamete production. Being able to determine the presence and quantity of the OA and UA in moringa and pawpaw seeds will allow for calculation of optimal inclusion levels of these acids in animal diets for antifertility-activity. The purpose of the study was thus to quantify the levels of OA and UA in Moringa and pawpaw seed powder by means of ultra-high performance liquid chromatography with electrospray ionization tandem mass spectrometry （UHPLC-ESI-MS/MS）. Only OA was detected in moringa seeds at a concentration level of 0.508 p.g/g ＋ 0.032 pg/g dry weight. UA and OA could not be detected in pawpaw seeds used in this study. The presence of OA in moringa seeds suggest that the seeds can be included in tilapia diets as a potential antifertility treatment to control precocious breeding in tilapia culture in small scale farming systems in Sub-Saharan Africa. Further studies are warranted to determine the levels of OA and UA composition in moringa seeds from other parts of the Sub-Saharan Africa （other than Zambia）.     

Estimating the Fresh Vegetables Demand System in Jordan： A Linear Approximate Almost Ideal Demand System

The main objective of this research is to estimate the different types of demand elasticities for the main fresh vegetables consumed in Jordan. The estimated elasticities can be used to measure the impacts of agricultural policies and can be used to predict future consumption in the context of food security in terms of access, availability, stability, and food quality. The reported demand estimates were obtained through the estimation of a Linear Approximate Almost Ideal Demand Systems （LA/AIDS） for Jordan fresh vegetable crops demand system using the most recent cross-sectional data of household expenditure survey in 2005. A censored regression method for the system of equations was used to analyze fresh vegetables consumption patterns. This method allows for inclusion of a large number of zero consumption for some foods through two-step demand system estimation. All of the own-price demand elasticities have the correct negative signs and statistically significant. According to the expenditure elasticity, tomato, cucumber, and potato are the necessity goods. The mean budget shares indicate that consumers spend 30 percent of their allocated budget to vegetables on tomatoes and potatoes. The green bean elasticity is the highest indicating that demand for beans is highly responsive to any changes in the price. The expenditure elasticities reveal that the demand on all vegetables is expected to grow over the coming few years. High own-price elasticities of all vegetables studied suggests that any changes in the prices of these crops could bring about a significant shift in fruits and vegetable constanption patterns.     

Hydrolytic Enzyme Inhibitors and Necrotic Reactions in Potato Leaves Reduce Reproductive Success of Colorado Potato Beetle

In field and laboratory conditions the reproductive potential （survival at different stages of development） of the Colorado potato beetle has been measured, the dependence of the parameters of insects fertility on varietal features of the feed has been investigated, the food activity of the representatives of insects from four areas of the Southern Urals has been measured, the intensity and time of hypersensitivity reactions on potato leaves has been defined. In laboratory experiments, the level of activity of hydrolytic enzymes in insects and the level of activity of these enzymes inhibitors in the leaves of three potato varieties differing in their resistance to the Colorado potato beetle have been determined. The results show that the insects-representatives of different samples have different food activity in relation to different potato varieties. High mortality rates were revealed at feeding with leaves of potato of the Bashkir variety characterized by a high level of hydrolases inhibitors and relatively rapid development of necrotic reactions after the appearance of eggs laying on the leaves. We suppose that the neerogenetic barrier appearing in the form of necrosis is the major cause of the fetal mortality of insects. The level of the content of inhibitors inactivating larvae digestive enzymes affects the survival of insects at postembryonic stages. The speed of the necrosis emergence, the level of activity of digestive enzymes inhibitors in potato can be considered as criteria for the selection of breeding material for resistance to the Colorado potato beetle.     

Effects of Various Degrees of Antennal Ablation on Mating and Oviposition Preferences of the Diamondback Moth,Plutella xylostella L.

Using scanning electron microscopy, we investigated the distribution of the trichoid, basiconic, and coeloconic sensilla on the antennae of the diamondback moth （DBM;Plutella xylostella）. The trichoid sensilla were the most abundant sensory organ, and the male moth antennae host signiifcantly more trichoid sensilla than female moth antennae. Conversely, basiconic and coeloconic sensilla were found more frequently on female than on male antennae. We performed experiments with various degrees of antennal ablation and demonstrated that DBM antennae played a key role in the control of mating and oviposition. We found that neither oviposition preference nor mating behaviors changed signiifcantly when less than 1/4 of both antennae were removed. However, there was a signiifcant behavioral change when the antennae were ablated by more than half. As the length of the antenna was shortened, the successful mating rate decreased and mating peak was delayed. An otherwise consistent host preference for oviposition was eliminated when both antennae were completely removed. Furthermore, we found that the number of trichoid sensilla was positively correlated with mating rate and oviposition preference. However, the numbers of basiconic and coeloconic sensilla were not correlated with mating rate and mating peak, but highly correlated with oviposition preference. Taken together, our results indicate that antennal sensory information plays a critical role in the mating and oviposition behaviors of this economically important pest.     

Residual Effect of Long Term Application of Organic and Mineral Fertilizers on Selected Chemical Properties of a Savanna Alfisol

The residual effect of organic and mineral fertilizers on selected chemical properties of an Alfisol in the long term soil fertility trial established in 1950 at Samaru, Nigerian savanna was assessed. The trial was left fallow for fourteen years due to lack of funds. Topsoil was collected from plots that received three levels of cow dung （D）, nitrogen （N） and phosphorus （P） in all possible combinations. The soils were analyzed for selected chemical properties. Except for significant effect of applied P on available P, sole application of cow dung, N or P had no significant effect on all the measured soil properties. The interaction of D and P significantly affected the mean values of exchangeable Ca, Mg, K and ECEC in the range of 1.12-1.96, 0.62-1.11, 0.37-0.64 and 2.82-4.11 cmol/kg respectively. The most important results were the ability of the plot that received neither D nor P to significantly increase these parameters than the plots that received only one of the treatments. The results show that the fallow period has changed the effects of application of organic and mineral fertilizers on the soil chemical properties under continuous cultivation by modifying them towards those of a native savanna Alfisol.