Comparison of the genetic structure of populations of wild emmer wheat, <Emphasis Type="Italic">Triticum turgidum</Emphasis> ssp. <Emphasis Type="Italic">dicoccoides</Emphasis>, from Israel and Turkey revealed by AFLP analysis

The aim of the present study was to assess the genetic variation in several Israeli and Turkish populations of wild emmer wheat, Triticum turgidum ssp. dicoccoides, the progenitor of most domesticated wheat. Single spikes were collected in 2002 from 60 plants that grew in six different habitats in Ammiad, northeastern Israel (8–12 plants from each habitat), and in 1998 from 56 plants that grew in seven different habitats in Diyarbakir, southeastern Turkey (8 plants from each habitat). Seeds were planted in a nursery and DNA was extracted from every plant and analyzed by the fluorescent-based amplified fragment length polymorphism (AFLP) method. Seven primer combinations produced 788 discernible loci of which 48.6% were polymorphic in Israel and 40.5% in Turkey. The genetic diversity estimates P (frequency of polymorphic loci) and He (gene diversity) were higher in Ammiad than in Diyarbakir (means of P = 0.34 and He = 0.13 in Ammiad vs. P = 0.20 and He = 0.08 in Diyarbakir). Ammiad populations contained more unique alleles than Diyarbakir populations. The relative genetic diversity estimates (θ) values were 0.188 in Ammiad and 0.407 in Diyarbakir, suggesting better differentiation of the populations in Turkey. Genetic distance was larger between Israeli and Turkish populations than between populations of each country. The data indicate that the Israeli and Turkish populations are considerably diverged and that the Israeli populations are more polymorphic than the Turkish ones, having a larger within-populations genetic variation than among-populations one. The significance of the results in relation to the differentiation pattern of wild emmer in the Near East is discussed.     

Purification and characterization of Ocimum basilicum L. polyphenol oxidase

A partial characterization of polyphenol oxidase (PPO) activity in Ocimum basilicum L. is described. PPO in O. basilicum L. was extracted and purified through (NH4)2SO4 precipitation, dialysis, and a Sepharose 4B-l-tyrosine-p-aminobenzoic acid affinity column. The samples obtained from (NH4)2SO4 precipitation and dialysis were used for the characterization of PPO. At the end of purification by affinity chromatography, 11.5-fold purification was achived. The purified enzyme exhibited a clear single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The molecular mass of the enzyme was estimated to be approximately 54 kDa. The contents of total phenolic and protein of O. basilicum L. extracts were determined. The total phenolic content of O. basilicum L. was determined spectrophotometrically according to the Folin-Ciocalteu procedure and was found to be 280 mg 100 g(-1) on a fresh weight basis. The protein content was determined according to the Bradford method. The enzyme showed activity to 4-methylcatechol, catechol, and pyrogallol substrates, but not to tyrosine. Therefore, of these three substrates, 4-methylcatecol was the best substrate due to the highest V(max)/K(m) value, followed by pyrogallol and catechol. The optimum pH was at 6, 8, and 9 for 4-methylcatechol, catechol, and pyrogallol, respectively. The enzyme had an optimum temperature of 20, 40, and 50 degrees C for 4-methylcatechol, catechol, and pyrogallol, respectively. It was found that optimum temperature and pH were dependent on the substrates studied. The enzyme activity with increasing temperature and inactivation time for 4-methylcatechol, catechol, and pyrogallol substrates decreased due to heat denaturation of the enzyme.     

An Evaluation of the Response of Yield Monitors and Combines to Varying Yields

Comparisons were made between yield measurements with an impact based yield sensor and an electronic scale in adjacent harvest strips and on the same grain stream within a combine. Yield measurements in adjacent strip comparisons were more prone to errors as the segment lengths decreased. Grain yield difference between the yield sensor and electronic scale ranged from 5 to 14%, 4 to 13%, 3 to 12%, and 2 to 11% for 15, 30, 60, and 300 m long segments. The yield differences between neighboring segments might have been caused by yield variability to a degree; however, a consistent decrease in yield differences with increasing segment lengths implied that better accuracies could be obtained in longer management areas. The combine responses to grain yield changes and the effect of varying ground speed on accuracy were also evaluated by creating artificial yield patterns in harvest strips. Grain diffusion within the combine was more obvious when abrupt yield changes were introduced at known locations. Grain mixing and redistribution inside the combine may dictate the selection of segment sizes in the site-specific decision making process. Constant ground speed provided more stable grain flow values than varying ground speed. The average error in yield estimate was 3.4% and 5.2% at constant ground speed and varying speed, respectively. Careful calibration and constant combine speed were important to achieve better accuracy with the grain yield monitor.     

云南黄毛草莓的nrDNA ITS和cpDNA psbA-trnH序列分子鉴定及进化特征分析

[目的]利用核糖体DNA(nrDNA)ITS序列和叶绿体DNA(cpDNA)psbA-trnH序列对云南不同地理区域的黄毛草莓进行分子鉴定,并分析不同地理居群间的分子进化及地理分布特征,为黄毛草莓种质鉴定、保护及开发利用提供理论依据.[方法]以云南省12个不同地理区域的黄毛草莓居群样品为材料,PCR扩增其ITS和psbA-trnH序列,并进行双向测序及序列合并,分别基于ITS和psbA-trnH序列及二者合并序列构建系统发育进化树.最后利用DnaSP 5.10对ITS和psbA-trnH序列进行核苷酸多样性(π)及单倍型数目、类型和多样性(Hd)分析,并对黄毛草莓居群进行中性检验及分子进化特征分析.[结果]基于ITS和psbA-trnH序列的聚类分析结果均显示,12个不同地理区域的黄毛草莓居群样品均与GenBank数据库中下载的黄毛草莓聚在一个分支上,分支自展值均大于阈值(75%),表明这两种序列均可用于黄毛草莓种质的分子鉴定.基于二者合并序列的聚类分析结果与上述结果基本一致,但分支自展值达99%,表明该聚类分析结果更可靠.不同地理区域的黄毛草莓ITS序列间的遗传距离为0~0.014,排序为迪庆州>昆明市>文山州,psbA-trnH序列间的遗传距离为0~0.025,排序为昆明市>迪庆州>文山州,推测ITS和psbA-trnH序列均能显示黄毛草莓居群遗传分化与地理分布格局的相关性.ITS序列长度为668 bp,变异位点百分率为1.8%,共有8种单倍型,Hd和π分别为0.894±0.078和0.006,以昆明市黄毛草莓样品的单倍型最多,为4种;psbA-trnH序列有203 bp,变异位点百分率为2.5%,psbA-trnH序列共有5种单倍型,Hd和π分别为0.788±0.090和0.009,以昆明市黄毛草莓样品单倍型最多,为3种,表明两种序列的单倍型均呈现地理分布格局.黄毛草莓ITS和psbA-trnH序列的中性检验Tajima's D值分别为-0.673和0.227(P>0.1),表明云南省12个不同地理区域的黄毛草莓居群保持稳定状态,在截至目前的历史时间内不存在扩张.[结论]从云南不同地理区域采集的样品均为黄毛草莓.ITS序列和psbA-trnH序列均可作为黄毛草莓的DNA条形码,二者的合并序列更能准确鉴定黄毛草莓种,适用于黄毛草莓分子谱系地理学研究.     

Growth, Maturation, Induced Spawning, and Production of the First Generation of South American Catfish, Pseudoplatystoma sp., in North America

Growth, plasma steroids, and the appearance of gonads (histology and gonadosomatic index) were followed in South American catfish (surubim, Pseudoplatystoma sp.) raised in captivity in the aquaculture facility at The Ohio State University, Columbus, Ohio, USA, from 2003 until 2006. Broodstock growth showed a great individual variation and it did not seem sex dependent. The levels of 11‐ketotestosterone were high in males during the reproductive season. Three out of six females spawned after receiving two doses of carp pituitary extract (0.5 and 5 mg/kg) at 11‐h intervals. Fertilization was performed in only one female in February 2006. Egg size was 0.73 ± 0.06 mm in diameter at stripping. Two males released sperm, and it was used for fertilization. Sperm concentrations were 24 × 10⁹ and 15.5 × 10⁹ spermatozoa/mL in Male 1 and Male 2, respectively, and viability was confirmed after activation in 0.3% NaCl. Embryo survival at 9 h after fertilization was 44 and 23% for Male 1 and Male 2, respectively. Embryos hatched 15 h after fertilization. Larvae were 3.53 ± 0.09 mm in length at hatching and were successfully raised (72% survival after 2 wks) using live brine shrimp nauplii.     

Investigation of tetracycline and degradation products in Euphrates river receiving outflows of trout farms

In this study, tetracycline (TC), epitetracycline (ETC), 4‐epianhydrotetracycline (EATC) and anhydrotetracycline (ATC) concentrations were determined in the surface waters carrying outflows of trout farms. The samples were taken from downstream of Keban Dam and upstream of Karakaya Dam Lake, which are located in the Euphrates and Tigris River Basin. The occurrence of TC and degradation products (DPs) was proved in the sampling points which take the outflows of the trout farms. Tetracycline and DPs were under the detection limits in sampling points where the trout farms do not exist. The highest TC concentration was detected as 50.0 ± 2.5 μg L^?1 (1st week), whereas the lowest TC concentration was 8.2 ± 0.41 μg L^?1 (7th week). The highest ETC concentration was 88.1 ± 4.4 μg L^?1 (3rd week)and the lowest ETC concentration was 9.4 ± 0.4 μg L^?1 (3rd week). The highest and lowest EATC concentrations were detected as 35.8 ± 1.8 μg L^?1 (2nd week) and 8.2 ± 0.4 μg L^?1 (2nd week) respectively. The highest ATC concentration was 28.3 ± 1.4 μg L^?1 (3rd week), whereas the lowest was 6.54 ± 0.34 μg L^?1 (7th week). Tetracycline and DP concentrations detected in surface waters followed the following order: ETC>TC>EATC>ATC.     

Changes in Testicular Development, Ultrasonographic and Histological Appearance of the Testis in Buck Kids Immunized Against LHRH Using Recombinant LHRH Fusion Protein

This study was designed to evaluate the effectiveness of recombinant Ovalbumin-LHRL (OL) immunization on changes in testicular size, histological appearance and testosterone production in buck kids. Thirty native buck kids at 18 weeks of age were divided into three groups, control (n = 10), immunization (n = 10) and castration (n = 10) groups. Immunized animals received OL protein generated by recombinant DNA technology. Ultrasonographic and histological examinations of the testes were performed. Animals were slaughtered at 44 weeks of age. Semen and epididymides were evaluated for the presence of sperm cells. Immunized animals generated anti-LHRH antibodies. Testosterone production, testicular and accessory glands development and sperm production were suppressed in the immunized animals (p < 0.01). Semineferous tubule diameters decreased (p < 0.01), basal membrane of the tubule was thickened and hyalinized in immunized kids. Immunization affected ultrasonographic appearance of the testes drastically. While testes of control animals gained their normal ultrasonographic appearance as the age increased, immunized animals had uniform hypoechogenic testicular structure as observed at 18 weeks of age until slaughter. Simultaneous histological and ultrasonographic evaluations indicated that the changes in testicular histology could partly be monitored via ultrasonographic imaging; nevertheless, it is difficult to claim that ultrasonographic image reflects the exact changes in such instances. In conclusion, these results indicate that recombinant OL fusion protein is effective in immunocastration in buck kids and has a potential to be used as an alternative to physical castration. Further researches should be conducted to help assessing reproductive status of testes from ultrasound images.     

The Effect of Total Anthocyanins Extracted From Sweet Cherry Cultivars on Carbonic Anhydrases and Antioxidant Activity

Total anthocyanins were extracted from eleven sweet cherry cultivars grown in Sakarya, Turkey. In vitro inhibition effects of extracted total anthocyanins on purified carbonic anhydrase I and II were investigated by using CO₂ as a substrate. The results showed that all extracted total anthocyanins inhibited the hCA I and hCA II enzyme activities. Among all cultivars, ‘Merton Premier’ was found to be the most active one against both hCA I (IC₅₀?=?0.83?µg/mL) and hCA II (IC₅₀?=?1.16?µg/mL). Additionally, the DPPH activities of the extracts were investigated as antioxidant properties. The results exhibited that ‘Churchill’ and ‘Merton Premier’ have high antioxidant activity with 74.102% and 73.503% DPPH activity, respectively.

     

A comparison of the gelling of isubgol,agar and gelrite on in vitro shoot regeneration and rooting of variety Samsun of tobacco (Nicotiana tabacum L.)

Agar is being used to solidify media for plant tissue culture since long. Both purity and type of agar or gelling agent influence the behaviour and growth of tissues in culture. The study using leaf disc explants of variety Samsun of tobacco compares adventitous shoot regeneration on 0.5 cm × 0.5 cm leaf discs cultured on MSD4X2 medium and rooting on MSO medium gelled with different blends of agar–isubgol, gelrite–isubgol, phytagel–isubgol or isubgol singly. It was found that irrespective of some problems associated with isubgol gel, the maximum number of shoot per explant were recorded on MSD4X2 medium gelled with 7 g/l isubgol. The longest shoots were recorded on MSD4X2 medium gelled with 9 g/l isubgol. Likewise, the highest number of roots were also recorded on MSO medium gelled with 7 g/l isubgol. For a given quantity of a medium, agar, gelrite/isubgol blends are very cheap compared to agar used singly. Moreover, blends of agar/isubgol, gelrite/isubgol gelled at low temperatures indicated safe use of these gels for heat labile substances in genetic transformation or tissue culture experiments. The results emphasized the potential of the isubgol used singly or in combination with agar and gelrite for economic commercial application, replacing the costliest, though not indispensable, gelling agent agar.     

The critical period of weed control in double-cropped soybean

Double-cropped soybean after winter cereals is the most common soybean production system in the eastern Mediterranean region of Turkey. Weeds are among the main obstacles to double-cropped soybean. A study was conducted in 2002 and 2003 to determine the critical period of weed control (CPWC) for double-cropped soybean. The treatments consisted of either allowing weeds to infest the crop for increasing durations after sowing, or maintaining plots weed-free for increasing durations after sowing. The Gompertz and logistic equations were fitted to relative yields representing the critical weed-free period and the critical time of weed removal, respectively. Johnsongrass (Sorghum halepense), common cocklebur (Xanthium strumarium) and field bindweed (Convolvulus arvensis) were the dominant weeds. For 5% crop loss level, the CPWC was almost all season long, whereas it was from V1 to R6-R7 growth stages for 10% yield loss level. These findings indicate that pre-sowing or pre-emergence control methods should be applied in the region to avoid greater crop losses.