Volatile compounds of selected strawberry varieties analyzed by purge-and-trap headspace GC-MS

Six strawberry (Fragaria x ananassa Duch.) varieties, Senga Sengana, Jonsok, Polka, Korona, Bounty, and Honeoye, were studied in relation to composition of their volatile headspace compounds collected by dynamic purge-and-trap concentration. Also, the influence of cultivation technique on the volatile compounds was tested by comparing conventionally and organically cultivated strawberry varieties. In addition, the effect of geographical origin on strawberry volatiles was investigated. The emphasis of this study was lay in the industrial utilization of strawberry. A total of 52 different volatile compounds were determined from frozen strawberries grown in 1997 and 1998. In addition to individual compounds, total areas of chromatogram profiles were compared. The major esters were found to be methyl butanoate, ethyl butanoate, methyl hexanoate, and ethyl hexanoate. With the application of principal component analysis and analysis of variance to the data matrix, the varieties were classified into three groups. Var. Honeoye was most different from the others. Organic cultivation had no effect on strawberry volatiles.     

Steryl phenolic acid esters in cereals and their milling fractions

The steryl ferulate contents of rye and wheat grains and their milling fractions were analyzed using a reversed-phase high-performance liquid chromatographic (HPLC) method. HPLC-mass spectrometry was used for identification. In addition, steryl ferulates of some selected milling byproducts were determined. The total steryl ferulate contents of rye and wheat grains were 6.0 and 6.3 mg/100 g, respectively. Uneven distribution of steryl ferulates in the grains led to considerable differences in the milling products; their steryl ferulate contents ranged from trace amounts in flours with low ash content to 20 and 34 mg/100 g in rye and wheat brans, respectively. Campestanyl ferulate and sitostanyl ferulate were the main components, followed by campesteryl ferulate and sitosteryl ferulate, whereas sitosterol was the main component in total sterols. Among the other samples, a byproduct of rice milling (pearling dust) was the best source of steryl ferulates, its total steryl ferulate content being 119 mg/100 g, whereas no measurable amounts of steryl ferulates were measured in oat bran or pearling dust of barley. The results indicated that rye and wheat and especially their bran fractions are comparable to corn as steryl ferulate sources.     

Yield and nitrogen concentration of above- and below-ground biomasses of red clover cultivars in pure stands and in mixtures with three grass species in northern Europe

Three red clover (Trifolium pratense) varieties differing in productivity and winter hardiness, Jokioinen, Betty and Ilte, were sown in a 2‐year (2003–2004) pot experiment in pure stands and mixtures with the grasses, timothy (Phleum pratense), tall fescue (Festuca arundinacea) and meadow fescue (Festuca pratensis). Grass growth dominated until fertilizer‐N, applied when the stands were sown, was depleted. Timothy was the least competitive of the grass species. Red clover variety Ilte produced the highest dry‐matter (DM) yields. Variety Betty yielded less, but allocated as much biomass to the root and stubble (soil‐bound) fraction as variety Ilte. Variety Jokioinen allocated least to the soil‐bound fraction. While the root structure and the starch concentration of the crown‐root area were similar in all varieties, the high ratio of soil‐bound: harvested fractions could be a key to the higher winter survival and higher DM yields of Betty under field conditions. At the end of the experiment, 3–5 g N pot^?1 (49–81 g m^?2) had been harvested and 0·7–1·5 g N pot^?1 (11–24 g m^?2) was left in the soil‐bound fraction, amounts depending on the red clover variety and grass mixture, with pure clover stands containing the highest N amounts. Because of the high N concentrations in the biomass of red clover, the proportion of red clover and conditions prevailing during canopy and root death in mixed stands are crucial for N mineralization and incorporation into new growth.     

花器发育调节基因gaga1转化大豆的初步研究

通过花粉管通道法用非洲菊基因gaga1转化N2899(质核互作雄性不育保持系)、通州豆、95—7等大豆受体。处理的花朵总数为4300朵，共获3000多粒种子。经卡那霉素田间鉴定，获得了14株抗卡那霉素的幼苗。通过抗性标记基因nptⅡ和目标基因gaga1的PCR检测，发现有两株N2899具有阳性信号，初步证明非洲菊基因gaga1已整合到这两株大豆的基因组中。形态分析表明：与未转化N2899相比，转基因大豆株型矮小，始花期提前，盛花期花数量较少，结荚不多。显微分析发现，与对照相比转基因大豆花器官结构没有明显改变。     

Clinical remission following plasmapheresis and corticosteroid treatment in a dog with acquired myasthenia gravis

A 7-year-old sexually intact male Labrador Retriever with regurgitation and generalized muscular weakness resulting from acquired myasthenia gravis received 2 plasmapheresis treatments in combination with corticosteroid treatment. Plasmapheresis was performed in an attempt to rapidly lower serum acetylcholine receptor binding antibody (AChR Ab) concentration. Seven days after the second plasmapheresis treatment, the dog's muscular strength was normal, which coincided with a 70% decrease in serum AChR Ab concentration. Because the dog also received corticosteroids, it is impossible to determine how much of the clinical improvement resulted from plasmapheresis.     

Prevalence, species composition, genetic variation and pathogenicity of clover rot (Sclerotinia trifoliorum) and Fusarium spp. in red clover in Finland

The species composition of a total of 173 red clover root fungal isolates from red clover roots from two established organic fields, a field in a transitional phase to organic and from two conventional fields was investigated based on morphology and molecular methods. Fusarium avenaceum was the most common Fusarium species overall but it occurrred less frequently in older organic fields. Gliocladium spp., Trichoderma spp. and Rhizoctonia spp. isolates were more common in the established organic clover fields, which had been under organic management for more than ten years and in one conventional field, than in a field still in the transitional phase. The taxonomical status of certain Fusarium, Alternaria and Sclerotinia isolates difficult to identify by morphological traits alone could be confirmed by species-specific primers and by comparing their ITS (internal transcribed spacer region) sequences to known sequences. The fingerprinting patterns of RAPD-PCR products could be used for the identification of fungal isolates and for studying the genetic variation among the isolates. Only one of the Fusarium isolates originating from apparently healthy red clover roots was clearly pathogenic to germinated red clover seedlings. In detached leaf experiments, the cvs Jokioinen and Ilte were more susceptible to one of the Sclerotinia trifoliorum isolates than cvs Betty and Bjursele, while all of them were equally susceptible to two other S. trifoliorum isolates. In further greenhouse experiments with intact plants it was possible to slow down the development of clover rot to some extent by means of one of the biological agents tested (Bacillus subtilis 10-VIZR, commercial name Alirin B), and almost completely by chemical control.     

Spring wheat response to timing of water deficit through sink and grain filling capacity

Water and nitrogen (N) availability are the main factors influencing crop growth globally. Poorly distributed or insufficient water for crop growth requirements decreases yields in drought-prone areas such as those with a Mediterranean type environment. Cereal grain yield is a complex trait of interrelated components: plants per unit land area, spikes per plant, spikelets per spike, grains per spikelet, and single grain weight (SGW). The effect of water limitation and timing on development of yield components was studied in detail at the spike level in spring wheat (Triticum aestivum L.) cultivar Amaretto. An experiment with three watering treatments (control watering, CONT; drought prior to pollination, DR1 and terminal drought, DR2) was arranged in a large greenhouse (20 m × 30 m), with the use of standard field-trial machinery. Automated blackout curtains were used to control day length, which was set to correspond to that at 40°N. With watering treatments, two N application rates (60 and 120 kg N ha⁻¹) were used to investigate the N effect and potential watering × N interaction on yield formation and realisation. The water deficit effect exceeded the effect of N on fertile floret and grain number and SGW. DR1 strongly reduced the number of fertile florets and grains, whereas terminal drought reduced the number of grains per spike. Resuming the watering at pollination markedly enhanced photosynthesis, and hence grain filling capacity, resulting in the highest SGW in DR1. Enhancement in availability of key resources was associated with reduced rate of fertile floret and grain abortion, which resulted in higher grain to fertile floret ratio in DR1. Spikelets in the mid-section of the spike dominated yield formation in all treatments. In DR1 this was especially emphasised as 53% of the grain yield was produced in spikelets 4–6, whereas in DR2 and CONT this was 45 and 41%, respectively. Grains in proximal position in the spikelets produced about 80% of the spike grain yield, the proportion being slightly higher in stressed plants and plants receiving 60 kg N. No marked N × water deficit treatment interaction occurred for any of the measured parameters.     

Radiative absorption enhancements due to the mixing state of atmospheric black carbon

Atmospheric black carbon (BC) warms Earth's climate, and its reduction has been targeted for near-term climate change mitigation. Models that include forcing by BC assume internal mixing with non-BC aerosol components that enhance BC absorption, often by a factor of ~2; such model estimates have yet to be clearly validated through atmospheric observations. Here, direct in situ measurements of BC absorption enhancements (E(abs)) and mixing state are reported for two California regions. The observed E(abs) is small-6% on average at 532 nm-and increases weakly with photochemical aging. The E(abs) is less than predicted from observationally constrained theoretical calculations, suggesting that many climate models may overestimate warming by BC. These ambient observations stand in contrast to laboratory measurements that show substantial E(abs) for BC are possible.     

Quality components of sea buckthorn (Hippophae rhamnoides) varieties

The sensory quality and chemical constituents of juices from seven sea buckthorn (Hippophaerhamnoides L.) varieties were studied in two consecutive seasons. The juices were generally described as sour and astringent, with low sweetness and fruity flavor. The differences in sensory quality as well as in chemical composition between samples and years were significant (p < 0.05) in most parameters studied. The Chuiskaya variety was described as the sweetest, with the strongest fruity flavor, whereas the varieties Avgustinka, Botanicheskaya, Trofimovskaya, and Raisa were the sourest and most astringent. Total sugar (fructose and glucose) varied from 1.9 to 7.1 g/100 mL in juice, total acid (malic and quinic acids) from 3.1 to 5.1 g/100 mL, vitamin C from 29 to 176 mg/100 mL, and pulp oil from 0.7 to 3.6%. The soluble solids were between 7.4 and 12.6, the pH between 2.7 and 2.9, and the titrable acidity between 2.0 and 3.7. The redness was highest on Avgustinka and Raisa, but there were no differences in yellowness. Total sugar and the sugar/acid ratio correlated positively with sweetness and negatively with sourness and astringency, whereas total acid and titrable acidity correlated positively with sourness and astringency and negatively with sweetness.     

Exploitation and length limit evaluation of Alabama bass in a South‐eastern USA reservoir

Alabama bass, Micropterus henshalli Hubbs & Bailey, are the dominant sportfish of Allatoona Reservoir, Georgia, USA, but no population assessment has been conducted. Thus, growth and total annual mortality were estimated in spring 2005, and a tagging study was conducted in 2006 and 2007 to estimate angler exploitation. These data were used with an age‐structured model to assess performance of a 356‐mm minimum length limit (MLL), a 406‐mm MLL and a 330‐ to 406‐mm protected slot length limit (SLL) compared to the present harvest regulation of no MLL. Mean annual exploitation varied from 12 to 22% each year and was generally highest for fish > 330 mm; total annual mortality was 44%. Models predicted a 49–153% increase in numbers of Alabama bass reaching 432 mm, a 22–66% decline in numbers harvested and only moderate declines in yield (5–25%) with the alternative harvest regulations compared to current conditions. The SLL may be an acceptable compromise to allow Allatoona Reservoir anglers to still harvest fish while also improving Alabama bass size structure.