Temporal trends in the secondary metabolite production of the sponge Aplysina aerophoba

Temporal changes in the production of secondary metabolites are far from being fully understood. Our study quantified, over a two-year period, the concentrations of brominated alkaloids in the ectosome and the choanosome of Aplysina aerophoba, and examined the temporal patterns of these natural products. Based on standard curves, we quantified the concentrations of aerophobin-2, aplysinamisin-1, and isofistularin-3: three of the four major peaks obtained through chemical profiling with high-performance liquid chromatography. Our results showed a striking variation in compound abundance between the outer and inner layers of the sponge. The ectosome showed high concentrations of bromocompounds during the summer months, while the choanosome followed no pattern. Additionally, we found that, from the outer layer of the sponge, aerophobin-2 and isofistularin-3 were significantly correlated with water temperature. The present study is one of the first to document quantitative seasonal variations in individual compounds over multiple years. Further studies will clarify the role of environmental, biological, and physiological factors in determining the seasonal patterns in the concentration of brominated alkaloids.     

Diversity of nonribosomal peptide synthetase genes in the microbial metagenomes of marine sponges

Genomic mining revealed one major nonribosomal peptide synthetase (NRPS) phylogenetic cluster in 12 marine sponge species, one ascidian, an actinobacterial isolate and seawater. Phylogenetic analysis predicts its taxonomic affiliation to the actinomycetes and hydroxy-phenyl-glycine as a likely substrate. Additionally, a phylogenetically distinct NRPS gene cluster was discovered in the microbial metagenome of the sponge Aplysina aerophoba, which shows highest similarities to NRPS genes that were previously assigned, by ways of single cell genomics, to a Chloroflexi sponge symbiont. Genomic mining studies such as the one presented here for NRPS genes, contribute to on-going efforts to characterize the genomic potential of sponge-associated microbiota for secondary metabolite biosynthesis.     

香蕉试管苗大田植株染色体变异的调查研究

对香蕉试管苗大田植株随机取样进行染色体变异的检测分析,发现染色体变异株的比例平均达６５．７％,其中最低５０％,最高８７．５％,混倍体是是的主要类型,约占４６％,而非整倍体居次,约占１９％。对试管苗大田植株同工酶变异的比较分析,发现变异性最大的酶是苹果酸脱氢酶,最小的是脂酶,由平均每位点等位基因有效数（Ａｅ）反映出的群体的分化程度显示,各群体分化程度不一致。聚类分析结果表明,同一苗厂的苗的相对遗传距     

Breeding and physiological aspects of potato cultivation in the Mediterranean region

Summary In the Mediterranean area the potato is a very important crop and can be cultivated throughout the year. However, tuber yields are generally much lower than those in Northern European countries. This is because the environmental and agro-economic conditions are different from those of Northern countries where most cultivars were developed. We feel that the objective for the “new Mediterranean potato” must be the availability of potato cultivars for each environment and for each planting season. Breeding programmes should focus on improving potato production within a specific agro-ecological Mediterranean area rather than improving crop production across areas. This paper reports aspects of potato breeding and physiology related to resistance to stress conditions in the Mediterranean area, with particular emphasis given to resistance to abiotic (heat, drought and frost) as well as biotic stresses. We also discuss the potential to produce seed tubers suitable for potato cultivation in the Mediterranean area.     

Volatile Organic Compounds,Indole, and Biogenic Amines Assessment in Two Mediterranean Irciniidae (Porifera,Demospongiae)

Solid phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS) was employed for the headspace determination of the volatile organic fraction emitted by two of the most common Mediterranean demosponges, Ircinia variabilis and Sarcotragus spinosulus, and of indole and some biogenic amines released by sponges in an aqueous medium. A total of 50/30 µm divinylbenzene/carboxen/polydimethylsiloxane and 75 µm carboxen/polydimethylsiloxane fibers were used for the headspace extraction of low molecular weight sulfur compounds from a hermetically sealed vial containing sponge fragments, while the direct immersion determination of indole and biogenic amines was performed. The biogenic amines were extracted after in-solution derivatization with isobutyl chloroformate. All analytical parameters (linearity, limits of detection, and quantification, precision, and recovery) were evaluated for indole and biogenic amines. SPME-GC-MS proved to be a reliable means of highlighting the differences between molecules released by different sponges, principally responsible for their smell. The combined approaches allowed the identification of several volatile compounds in the headspace and other molecules released by the sponges in an aqueous medium, including indole and the BAs cadaverine, histamine, isobutylamine, isopentylamine, propylamine, 2-phenylethylamine, putrescine and tryptamine. The results obtained represent a further contribution to the picture of odoriferous molecules secreted by sponges.     

Further Investigation of the Mediterranean Sponge Axinella polypoides: Isolation of a New Cyclonucleoside and a New Betaine

An exhaustive exploration into the metabolic content of the Mediterranean sponge Axinella-polypoides resulted in the isolation of the new betaine 5 and the new cyclonucleoside 8. The structures of the new metabolites were elucidated by spectroscopic methods assisted by computational methods. The analysis also provided evidence that the sponge does not elaborate pyrrole-imidazole alkaloids (PIAs) but, interestingly, it was shown to contain two already known cyclodipeptides, compounds 9 (verpacamide A) and 10.     

贵州不同生态区密度对春玉米干物质积累、转运及产量的影响

采用裂区设计,以5个春玉米品种为材料,设置3个种植密度,研究密度对各生态区春玉米干物质积累、转运和产量的影响及其相互关系。结果表明,密度与群体干物质积累量呈二次曲线关系,密度在9.11万株/hm²时积累量达最大值;各生态区总干物质积累量差异显著,其中威宁点最大,兴仁点最小。春玉米干物质总积累量与产量呈极显著正相关,叶片和子粒分配比例及对子粒贡献率与产量均呈显著正相关。密度与产量呈二次曲线关系,平均密度在8.86万株/hm²时产量最大,为11 844.22 kg/hm²;密度每增加1万株/hm²,有效穗数平均增加0.7万株,穗粒数降低20粒,千粒重降低14 g。各生态区产量表现为威宁>毕节>铜仁>安顺>兴仁。     

华南双季超级稻秧苗生理特性的研究

2001年早、晚季在广州对华南超级常规稻品种广超3号和胜泰1号、两系法超级杂交稻组合粤杂122等7个材料秧苗期的干物重、叶片叶绿素含量、根系活力和发根力等几个生理性状进行了测定,并分析了生理性状的品种(组合)间差异、生理性状与干物重之间的相互关系等,结果表明:①早季时宜用Chl a、晚季时宜用Chl b作为鉴别秧苗素质的生理指标.②对Chl a、Chl b、根系活力,所发最大根长度,发根条数与干重的通径分析表明,早季Chl a对干重有最大的正直接效应,Chl b对干重有最大的负直接效应;晚季Chl b对干重有最大的正直接效应,Chl a对干重有最大的负直接效应.提出了华南双季超级稻理想株型育种中宜掌握的秧苗期生理指标.     

Towards Commercial Production of Sponge Medicines

Sponges can provide potential drugs against many major world-wide occurring diseases. Despite the high potential of sponge derived drugs no sustainable production method has been developed. Thus far it is not fully understood why, when, where and how these metabolites are produced in sponges. For the near future sea-based sponge culture seems to be the best production method. However, for controlled production in a defined system it is better to develop in vitro production methods, like in vitro sponge culture or even better sponge cell culture, culture methods for symbionts or the transfer of production routes into another host. We still have insufficient information about the background of metabolite production in sponges. Before production methods are developed we should first focus on factors that can induce metabolite production. This could be done in the natural habitat by studying the relation between stress factors (such as predation) and the production of bioactive metabolites. The location of production within the sponge should be identified in order to choose between sponge cell culture and symbiont culture. Alternatively the biosynthetic pathways could be introduced into hosts that can be cultured. For this the biosynthetic pathway of metabolite production should be unraveled, as well as the genes involved. This review discusses the current state of sponge metabolite production and the steps that need to be taken to develop commercial production techniques. The different possible production techniques are also discussed.     

A new hydroxylated nonaprenylhydroquinone from the Mediterranean marine sponge Sarcotragus spinosulus

Chemical investigation of the Mediterranean sponge Sarcotragus spinosulus led to the isolation of a new hydroxylated nonaprenylhydroquinone, along with two known metabolites, hepta- and octaprenylhydroquinones. The structure of the new metabolite was assigned by extensive 1D and 2D NMR analyses and MS studies. The antileukemic effect of the three compounds towards the chronic myelogenous leukemia (CML) cells line K562 was also evaluated.     

强光下籼稻叶片色素光漂白及其组分变化

 在光氧化条件下(强光、低CO2 低O2)调查了 54个籼稻品种叶绿素（chl）和类胡萝 素（Car）的光漂白差异，并根据这些特点划分为4类。I） Chl和Car含量都较高的耐光氧化类型（6个）；II) 两者都较低的不耐光氧化类型(13个)；III） Chl含量较高而Car含量较低的持殊类型(3个)；两者含量介于中间的中间类型（32个）。在正常条件下，耐光氧化类型的Chl、 Car含量以及Chla，b、 Car／Chl值都较不耐的低。各类型中的Chl与Car、Chl a与Chl b之间都呈线性关系。但经光氧化处理后，各类型的Chl、Car含量，Chl a／b值和SOD 活性都下降，只有Car/Chl值上升。耐的类型除SOD活性变化较大外，其他参数变化较少。这似乎说明色素组分的相对稳定是耐光氧化的一个特性，且与SOD清除活性氧功能有关。     

不同品种茶树叶片功能性状及光合特性的比较

以18个茶树品种(系)为研究对象,测量了茶树叶片的叶面积、叶形指数、比叶面积、干物质含量、叶绿素a、叶绿素b及其比值、叶绿素总量、类胡萝卜素及光合特性,并分析了叶片功能性状和光合特性之间的相关性。结果表明,茶树叶片叶形指数、干物质含量、气孔导度的变异系数低于10%,其余11项指标的变异系数为15.08%~43.22%,表现出较高的多样性水平;比叶面积与干物质含量之间存在显著负相关,叶形指数和叶面积与其他叶片功能指标均无显著相关;干物质含量与光合色素之间存在显著相关,叶绿素a、叶绿素b、叶绿素a/叶绿素b、叶绿素总量和类胡萝卜素两两之间存在极显著相关性;净光合速率、气孔导度、蒸腾速率两两之间存在极显著正相关,且气孔导度与胞间CO_2浓度呈显著正相关,茶叶光合速率主要受气孔限制的影响;净光合速率与干物质含量之间存在显著正相关,净光合速率、蒸腾速率与光合色素含量之间存在显著或极显著正相关,说明光合色素含量高的品种具有更强的光合能力和干物质积累能力;气孔导度、水分利用效率与叶片功能性状之间相关性不显著。14号茶树品种比叶面积相对较低,同时具有较高的干物质含量、净光合速率和水分利用效率,属于抗旱性较强、光合速率和水分利用效率高的品种,可作为抗旱性强、高光效的茶树品种进一步选育和应用。     

Optimal fallow area and location for multifunctional benefits of a paddy field during drought periods

Paddy fields not only serve to produce food but also have a variety of important ecological functions. Apart from the internal benefit (i.e., crop production), there are external benefits (i.e., reduction of greenhouse gases, oxygen generation, reduction of biological oxygen demand, flood mitigation, and other functions that are difficult to quantify). In the present study, the optimal fallow locations and areas were determined for evaluating the multifunctional benefits of paddy fields during drought periods, by using an optimization model for fallow fields under different exceedance probabilities of river inflows. For each time step, the appropriate probability distributions for river inflows to the Chi-Chi Weir (range 50–90 %) for generating system inflows were obtained. The optimization model for fallow fields was solved using Lingo. It was observed that the external benefits of paddy fields accounted for 76 % of total benefits, with the production benefit accounting for the remainder. The total benefits decreased as the exceedance probability of river discharges increased. Our findings indicate that fallow areas increase as irrigation areas shift downstream.     

块茎大小与马铃薯淀粉粒度分布的关系

淀粉粒度是衡量马铃薯淀粉品质的一个重要指标。测定了5个马铃薯品种不同大小块茎淀粉的平均粒径及离散度,得出以下结论:克新13号、克新19号、克新21号块茎质量大于250 g时其淀粉的平均粒径最大,克新18号、克新20号块茎质量在150~250 g之间其淀粉的平均粒径最大;5个品种均是块茎质量小于75 g时的淀粉平均粒径最小。5个品种之间比较表明,克新20号淀粉的平均粒径最小,克新13号在块茎质量大于75 g时其淀粉的平均粒径最大。克新13号、克新18号、克新19号、克新21号在块茎质量大于250 g时淀粉的粒度分布最均匀,克新20号块茎质量在150~250 g之间时淀粉的粒度分布最均匀。     

Spatial heterogeneity and other sources of variance in sward height as measured by the sonic and HFRO sward sticks

Measurements of undisturbed sward surface height (sward height) were made using the HFRO and sonic sward sticks at 20 cm intervals along 100 m transects laid across paddocks grazed by either sheep, cattle or goats. Measurements of sward height were also made at 5 cm intervals along 10 m transects laid across the same paddocks using the HFRO sward stick alone. The variance of the measurements from each transect was partitioned across the range of spatial scales of roughness present using spectral analysis. The variance of the sward surface height appeared to be dominated by variation with spatial scales of less than 1 to 2 m. The variances of measurements made with the two sward sticks were similar despite the greater sampling area of the sonic sward stick. This was due to the presence of variation at spatial scales much larger than the sampling area of either instrument and to a greater contribution from non-spatially related sources to the variance of the sonic sward stick measurements. The use of weighted disc meters for obtaining the mean height of continuously grazed sward deserves re-examination, while automation of the sonic sward stick may be worthwhile if the spatial distribution of herbage is to be described.     

啤酒大麦品种的千粒重和环境变异研究

千粒重是啤酒大麦重要的产量与品质性状。本研究通过来自全国各地的 10个品种在我国不同地区 8个试验点种植的结果分析 ,表明千粒重在品种间、地区间以及年度间均存在显著差异。两年平均 ,浙农大 6号和单二大麦分别为千粒重最高和最低的品种 ;8个试点中以荆州点的平均粒重最高 ,泰安点最低。     

Detection of Glycoalkaloids and Chlorophyll in Potatoes (<Emphasis Type="Italic">Solanum tuberosum</Emphasis> L.) by Hyperspectral Imaging

The purpose of the study was to investigate the use of hyperspectral imaging (HSI) to detect and quantify chlorophyll (Chl) and total glycoalkaloid concentrations (TGA) in potatoes. To create a set of tubers with different concentrations of Chl and TGA, potatoes of four varieties were wounded or treated with red, blue, red/blue, UV-a, UV-b or UV-c light. HSI analyses were performed with a reflection based setup implemented in an industrial potato sorting machine. After hyperspectral analyses, the peel was sampled, and concentrations of Chl and total TGA were determined. Results showed that the HSI system predicted the concentrations of Chl with a relatively high degree of accuracy, and a prediction R² value of 0.92. Prediction of TGA concentrations performed to a much lesser extent, and the overall prediction R² value was only 0.21. Moderate soil covers only affected the prediction powers to a minor degree.     

7种观叶小盆栽植物的光合特性与耐阴性研究

研究了7种常见小盆栽植物的光合特性,以期为生产管理提供理论依据.通过测定供试植物叶片的形态特征、光合作用日变化和光响应曲线,并对测定结果进行方差分析和相关分析.结果表明:供试的7种植物总叶绿素(Chl)含量存在较大的差异,叶绿素a/叶绿素b值在1.66～2.10之间,均小于3;人参榕的净光合速率(Pn)与蒸腾速率(Tr)极显著地高于其它植物,白鹤芋、绿萝和咖啡树间的Pn差异不显著,而圆叶椒草和银后亮丝草的Pn与Tr均较低.相关性分析表明7种植物的Pn与胞间CO2浓度(Ci)呈极显著相关.综合各项指标表明供试的7种植物对弱光利用能力均较强.其中人参榕的耐阴能力最强,对光适应的生态幅较宽,既有较强的耐阴能力,又能适应较强的阳光辐射;圆叶椒草和银后亮丝草的耐阴能力相对较弱,但能更好地利用基质水分.     

茶树不同叶位叶片功能性状与光合特性研究

以5个茶树品种(系)为研究对象,分析了茶树新梢不同叶位叶片的叶面积(LA)、叶形指数(LI)、比叶面积(SLA)、干物质含量(LDMC)、叶绿素a(Chla)、叶绿素b(Chlb)、叶绿素总量(Chl)、类胡萝卜素(Car)及光合特性,并研究了叶片功能性状和光合特性之间的相关性。结果表明,不同叶位叶片的LA、LMDC、净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)由第1叶至第6叶基本呈现先增加后降低趋势,新梢中部3~4叶达到峰值,第1叶和第6叶显著降低(P0.05);不同叶位叶片LI和SLA基本呈现随着叶位增加而增加的趋势,第6叶的SLA均显著高于其他叶位(P0.05);第1~4叶的Chla、Chlb和Chl含量较高,第6叶Chla、Chlb和Chl含量显著低于其他叶位(P0.05),Car变化趋势不明显。LA与LI、LDMC、Chla、Chlb、Chl和Car之间存在显著或极显著正相关,与胞间CO2浓度(Ci)之间呈显著负相关,与其他指标相关性不显著;LI与其他指标不相关(LA除外);SLA与LDMC、Chla、Chlb、Chl、Car和Pn之间存在显著或极显著负相关,与Ci之间呈极显著正相关,与其他指标相关性不显著;LDMC与Chla、Chl和Pn之间存在显著或极显著正相关;Chla、Chlb、Chl和Car两两之间均存在极显著正相关,且均与Pn存在显著或极显著正相关;Gs和Tr与叶片功能性状不相关。分析以上结果可以得出,茶树新梢第3~4叶具有相对较大的LA和较强的光合能力,LDMC积累较大,可以作为表征茶树光合能力的供试叶片;SLA、LDMC和光合色素含量与Pn存在密切相关性,可作为评价茶树光合能力的指标。     

Yield formation strategies of durum wheat landraces with distinct pattern of dispersal within the Mediterranean basin I: Yield components

This study was undertaken to ascertain whether the pattern of dispersal of durum wheat within the Mediterranean basin is associated with variation in phenology and yield formation strategies. A set of 52 durum wheat landraces, previously genetically characterized as been dispersed by the north or south of the Mediterranean region, were grown in three rainfed sites in a dry-temperate region (Lleida, NE Spain), and crop phenology, yield and yield components were determined. Northern genotypes had a larger number of stems per unit area, but a lower percentage of fertile tillers and fewer grains per spike than southern landraces. Grain yield for the northern dispersal group was mainly related to variations in thousand-kernel weight, while the number of spikes per m² was the component most highly correlated with yield among southern genotypes. These contrasting yield formation strategies are probably a consequence of the different climates prevalent in the zones of adaptation, and likely conferred adaptive advantages to the genotypes of one or the other group. Our results suggest that gradual changes in yield components occurred during the movement of durum wheat from east to west through the north side of the Mediterranean basin. According to our results, the weight of grains and the number of spikes per unit area may be selection criteria to improve adaptation for the northern and the southern parts of the Mediterranean basin, respectively.