Influence of light quality on the germination of Betula papyrifera seeds

The influence of light quality on germination of unstratified birch seeds (Betula papyrifera) was investigated in a greenhouse study. Different light regimes were created with five plastic filters of different colour in combination with basic illumination. The filters were adjusted to equal levels of photosynthetically active radiation. The difference in light quality in terms of R : Fr ratio (red : far‐red light ratio) varied from 0.23 to 1.03. Germination was recorded 7, 10, 14, 21, 25, 31 and 36 days after sowing. Response to light quality was significant from 25 days after sowing (p < 0.043), and it was found that differences increased with time. Filters producing light regimes with low R : Fr ratios were found to reduce and delay germination of birch seeds. Germination after 36 days varied from 55% for the control treatment to 11% for the lowest R : Fr ratio. The relationship between seed germination percentage and R : FR ratio was found to be significant (p < 0.017) with an R‐sq value of 88.6%.     

Pulsed light effects on surface decontamination,physical qualities and nutritional composition of tomato fruit

Pulsed light (PL) is a nonthermal food technology with a potential as postharvest decontamination strategy for fruit and vegetables. The feasibility of PL in extending shelf-life of food products while assuring appropriate quality is still under investigation. The effect of pulsed light (PL) on surface decontamination (natural and inoculated microorganisms), physical (colour, texture and weight) and nutritional quality (ascorbic acid and major carotenoids) was investigated in red-ripe tomatoes during 15 days of storage at 20 °C. The application of PL treatments at fluences of 2.68 and 5.36 J/cm² reduced microbial loads during storage of whole tomatoes. One log₁₀ reduction on the microflora present in both skin and peduncle scar parts of the tomato was obtained with a fluence of 4 J/cm². Fluences of 2.2 J/cm² allowed a 2.3 log₁₀ reduction of Saccharomyces cerevisiae inoculated onto the tomato surface. Softening, increased loss of weight, and wrinkles on the tomato surface appeared after 3 days on PL treated tomato fruit. Ascorbic acid levels remained unchanged during storage. Total lycopene, α-carotene and β-carotene contents and lycopene isomerisation percent were higher in tomato extracts prepared with fresh tomato fruit treated with a high PL dose of 30 J/cm². An increase in the bio-accessibility of lycopene was observed in hot-break purees prepared with fresh tomatoes treated at 5.36 J/cm² and stored 15 days. In conclusion, PL treatment of fresh tomato would result in a reduction in microbiological contaminants without compromising the nutritional value; but it did induce some appearance defects.     

基于LIN总线的车灯控制器的设计

LIN总线是一种低成本的串行通讯网络,用于实现汽车网络中的分布式电子系统控制。提出一种LIN总线的车灯控制器的设计方案,详细介绍LIN总线在车灯模块中的应用。该系统可以通过LIN总线的应用,准确、可靠、实时的对数据进行传输,实现对车灯的控制。     

辣椒幼苗叶片解剖特征及光合特性对弱光的响应

 以弱光适应性不同的4个辣椒(Capsicum annuum L. )基因型（甜味型和辣味型）为试材，在人工气候室内研究了弱光（75~100 μmol·m^-2·s^-1）条件下辣椒幼苗叶片显微结构、叶绿体超微结构、气孔特征特性，以及光合特性的适应性变化。结果表明，弱光下辣椒幼苗叶片变薄，栅栏组织/海绵组织比值增加，'伏地尖'（辣味型）和'上海园椒'（甜味型）具有较高的栅栏组织/海绵组织比值；叶绿体数目减少，但叶绿体变大，基粒数、基粒厚度和基粒片层增加，淀粉粒增大、增多，2个辣味型材料比2个甜味型材料具有较高的叶绿体数和基粒数。辣椒（甜味型）展叶过程中下表皮气孔密度下降，而展叶14 d以后的气孔指数和单片叶气孔数变化不大。弱光下叶片气孔密度、气孔指数和单片叶气孔数减小，但气孔变大，其中'上海园椒'气孔纵轴、横轴较正常光照下增加，'20078'则横轴显著增加；弱光环境中叶片表皮细胞变大并发生扭曲皱褶，气孔与表皮平齐或略显外突，保卫细胞角质层上可观察到明显的环状褶皱。弱光下辣椒幼苗的光饱和CO₂同化速率(Asat)、暗呼吸速率(Rd)、夜间呼吸速率(R_n)、光呼吸速率(R_p)、光补偿点(LCP)、光饱和点(LSP)、CO₂补偿点(Г)、CO₂饱和点(CSP)、羧化效率(CE)以及RuBP最大再生速率下降，表观量子效率(Фi)上升；辣味型较甜味型材料Asat下降幅度较小，并且具有较低的LCP 、LSP 及其Rd 、Rn和Rp。弱光下各基因型辣椒的光合启动时间均有所延长，弱光敏感性材料表现更为明显。     

Some factors affecting the intensity and locus of expression of mineral deficiency and toxicity symptoms by plants

Abstract

Using yields of plants obtained at various times of the year and from probable assumptions relative to sugar production, solute sorption, and solute distributions between roots and tops it has been deduced that both deficiencies and toxicities in mineral nutrition would be expected to be revealed earlier or more prominently in a summer season. Light is the primary determining environmental factor. The locus of nutrient deficiency revelation depends on the remobility of the element in the plant; toxic disorder is usually revealed in the oldest foliar parts.     

Ontogenetic behaviour and swimming ability of the endangered eastern freshwater cod,Maccullochella ikei,with notes on growth and development

Abstract – Understanding the larval ecology of individual fish species is fundamental in ensuring their long‐term conservation. The endangered eastern freshwater cod, Maccullochella ikei, is endemic to the Clarence and Richmond River systems of north‐eastern New South Wales, Australia. Little is known about the behaviour of larval M. ikei in the wild, particularly before and after the swim‐up stage, and following dispersal from the nest site. The aims of this study were to quantify the swimming ability, depth selection, light preference and substrate selection of hatchling to day‐30 M. ikei under controlled laboratory conditions, and to describe its growth and development over the same period. Maccullochella ikei larvae grew constantly but not consistently during the experiment. Exogenous feeding commenced around day 12, prior to the full exhaustion of the yolk. Maximal swimming ability improved daily, but maximum swimming speed declined significantly between days 12 and 13 and remained low. Maccullochella ikei larvae were initially photonegative but were positively phototactic by day 10. Depth selection was for the benthos until day 8, beyond which time larvae dispersed to all depths when released. Substrate selection was for sand in younger larvae but changed to upstream substrates as the experiment progressed. The results of the current study suggest that the period between day 10 and day 20 is critical in the early ontogeny of M. ikei, when it switched phototrophic behaviour, transitioned from endogenous to exogenous feeding and experienced a decline in swimming ability.     

工业填料塔真空精馏分离松轻油

松轻油先用碱液进行预处理,再用工业SM-250型孔板波纹填料塔(φ300 mm、高 10.1 m),以真空间歇操作方式进行一次性精馏分离,分别得到富含蒎烯、莰烯、苧烯(或双戊烯)及对-伞花烃、萜烯醇等的馏分.以精馏原料松轻油的投料量为基准,α-蒎烯含量 74.4% 以上的馏分得率为 28.5%,其中α-蒎烯含量在 80.1% 以上的馏分得率为 22.4%;α-蒎烯与β-蒎烯两者含量在 42.6% 以上的馏分得率为 45.2%;馏分中蒎烯、莰烯合计含量最高达 99.1%,馏分中莰烯的最高含量达 36%;蒎烯、莰烯合计含量达到 92.5%以上的馏分得率为 31.8%;苧烯(或双戊烯)及对-伞花烃含量达 64.2% 以上的馏分得率为 23.1%.萜烯醇最高含量为 49% 的馏分得率只有 3.1%.     

Botrytis cinerea in greenhouse vegetables: chemical,cultural, physiological and biological controls and their integration

Botrytis cinerea is an ubiquitous pathogen which causes severe losses in many fruit, vegetable and ornamental crops. The pathogen infects leaves, stems, flowers and fruits. The complexity of diseases caused by B. cinerea in greenhouses makes this pathogen one of the most important diseases of vegetable crops in greenhouse in many countries. In general, epidemics occur in cool and humid conditions, which favour infection and may also predispose the host to become susceptible. High relative humidity in the greenhouse and free moisture on plant surfaces are considered the most important environmental factors which influence infection by B. cinerea. In this review we specify the factors affecting the development of diseases incited by B. cinerea and discuss different approaches for its suppression. Chemical and non-chemical controls are outlined and their integration is discussed. Finally, achievements, gaps in knowledge, and future needs are indicated. The most common means for disease management is by application of chemical fungicides. Both spraying of fungicides and application of fungicides directly to sporulating wounds is practiced. However, high activity of several fungicides is being lost, at least in part, due to the development of resistance. As fungicides still remain an important tool for control of epidemics caused by B. cinerea, it is important to monitor populations of the pathogen for their resistance towards potential fungicides. Cultural measures can be a powerful means to suppress plant diseases in greenhouses where the value of crops is high and the farmers make considerable efforts during long cropping seasons. Such measures are usually aimed at altering the microclimate in the canopy and around susceptible plant organs, prevention of inoculum entrance into the greenhouse and its build up, and, rendering the host plants less susceptible to diseases. Calcium loading of plant tissues and alteration of nitrogen fertilization reduce susceptibility to Botrytis. Cultivars resistant to B. cinerea are not available. Another alternative methods to control B. cinerea is by means of biological control agents. At least one preparation is already available in the market and in many cases it was as effective as the conventional fungicides. A decision support system was recently developed for integration of chemical and biological controls. Adaquate suppression of B. cinerea diseases in greenhouse crops is an attainable goal. In our opinion this goal can be reached by considering the ecology of the pathosystem in its broader sense and by integration of all possible control measures. This implies optimization of plant nutrition, microlimate and control (cultural, biological, physiological and, if necessary, chemical) measures. Moreover, Botrytis management must be incorporated in a more holistic system that is compatible with insect control, crop production systems and profitability of the crop.     

几种生态因子对银纹夜蛾实验种群的影响

本文以主要质量指标对比了用人工半合成饲料与天然饲料饲养银纹夜蛾的结果，表明人工半合成饲料明显优于天然饲料。研究了幼虫饲养密度对存活的影响，四龄末幼虫存活率与一龄幼虫密度呈抛物线关系，化蛹率、蛹重与五幼虫密度呈直线下降关系，相对湿度、夜间光照强度、食物等对成虫生殖有显著影响。     

New aphid species for italy caught by suction trap

Six aphid species new for Italy were caught by suction trap in the Friuli-Venezia Giulia region, Italy. They are:Chaetosiphon chaetosiphon (Nevsky),Illinoia morrisoni (Swain),Myzodium modestum (Hottes),Pseudacaudella rubida (Börner),Schizaphis longicaudata Hille Ris Lambers andTrichosiphonaphis (Xenomyzus)polygonifoliae (Shinji). All species are provided here with characteristic morphological information and line drawings.