施甸烟区植烟土壤肥力适宜性评价

该文对在2003-2013年间施甸县1 225个土壤样品的9项指标进行了测试分析,并利用模糊数学原理和多元统计方法进行了综合评价。结果表明：全县土壤肥力存在较大差异,甚至有的土壤有机质、碱解氮、速效磷、速效钾、有效硼、有效锌、水溶性氯极度缺乏;全县土壤肥力综合指标值平均为0．623,变幅为0．199～0．928,变异系数为19．74％,其中Ⅰ、Ⅱ、Ⅲ、Ⅳ级土壤所占比例分别为16．08％、54．04％、27．02％、2．86％,水长、仁和的I～Ⅲ级土壤达100％。因此,施句烟区在足量施用有机肥的基础上,控氮,增磷钾,补施氯硼锌,以实现烟区土壤养分平衡。     

基于多重多元回归的木材干燥质量预测模型

利用多重多元回归分析理论,在干燥过程中建立干燥指标与其影响因素之间的预测模型,从而达到预测含水率、应力的目的。选择温度、相对湿度、干燥时间作为自变量,应力、含水率作为因变量,建立多对多的木材干燥质量预测模型。模型的显著性检验表明,模型的拟合度较高,具有较好的预测能力。     

Using elevation to aid the geostatistical mapping of rainfall erosivity

This paper addresses the issue of incorporating a digital elevation model into the mapping of annual and monthly erosivity values in the Algarve region (Portugal). Besides linear regression of erosivity against elevation, three geostatistical algorithms are introduced: simple kriging with varying local means (SKlm), kriging with an external drift (KED) and colocated cokriging. Cross validation indicates that the straightforward linear regression, which ignores the information provided by neighboring climatic stations, yields the largest prediction errors in most situations. Smaller prediction errors are produced by SKlm and KED that both use elevation to inform on the local mean of erosivity; kriging with an external drift allows one to assess the relation between the two variables within each kriging search neighborhood instead of globally as for simple kriging with varying local means. The best results are generally obtained using cokriging that incorporates the secondary information directly into the computation of the erosivity estimate. The trade-off cost is the inference and modeling of three direct and cross semivariograms.     

Application of near infrared reflectance (NIR) and fluorescence spectroscopy to analysis of microbiological and chemical properties of arctic soil

Applicability of near infrared reflectance (NIR) and fluorescence spectroscopic techniques was tested on highly organic arctic soil. Soil samples were obtained at a long-term climate change manipulation experiment at a subarctic fell heath in Abisko, northern Sweden. The ecosystem had been exposed to treatments simulating increasing temperature (open-top greenhouses), higher nutrient availability (NPK fertilization) and increasing cloudiness (shading cloths) for 15 years prior to the sampling. For each of the 72 samples from the 0 to 5 cm soil depth and 36 samples from the 5 to 10 cm depth, the wavelength range of 400-2500 nm (visible and near infrared spectrum) was scanned with a NIR spectrophotometer and fluorescence excitation-emission matrices (EEMs) were recorded with a spectrofluorometer.Principal component analyses of the visible, NIR and fluorescence spectra clearly separated the treatments, which indicates that the chemical composition of the soil and its spectral properties had changed during the climate change simulation. Similarly to the results from the conventional analyses of soil chemical and microbiological properties, fertilization treatment posed strongest effects on the spectra. Partial least-squares (PLS) regression methods with cross-validation were used to analyse relationships between the spectroscopic data and the chemical and microbiological data derived from the conventional analyses. The fluorescence EEMs of the dried solid soil samples were moderately related to soil ergosterol content (correlation coefficient r=0.84), bacterial activity analysed by leucine incorporation technique (r=0.78) and total phospholipid fatty acid (PLFA) content (r=0.74), but in general fluorescence provided inferior predictions of the chemical and microbiological variables to NIR. NIR was highly related to soil organic matter content (r>0.9) and showed promising predictions of soil ergosterol content (r>0.9), microbial biomass C, microbial biomass P, and total PLFA contents (r=0.78-0.79).These results suggest that especially NIR could be used to predict soil organic matter and fungal biomass. Since it is rapid and inexpensive, and requires little sample mass, it could be used as a ‘quick and dirty’ technique to estimate progression of the treatment responses in long-term ecosystem experiments, where extensive soil sampling is to be avoided.     

Evaluation of genetic identity and variation of local apple cultivars (<Emphasis Type="Italic">Malus</Emphasis> × <Emphasis Type="Italic">domestica</Emphasis> Borkh.) from Spain using microsatellite markers

A collection of 114 local cultivars of Malus × domestica Borkh. from the Northwest of Spain and a group of 26 non-native commercial cultivars, were studied in order to determine the level of genetic differentiation between them, to know the population genetic structure of the three main production regions in North Spain, and to detect possible duplications, misidentifications, and intrusions of foreign cultivars into the present day Spanish apple gene pools. Ten primer pairs of microsatellite loci were selected from previous studies on apple. Allelic frequencies were used to estimate the average expected heterozygosity (Hexp) and F-statistics. A Principal Component Analysis and a Cluster Analysis were conducted in order to determine the relationships among cultivars. Considering all populations (Spanish and commercial cultivars) we found 119 alleles with the 10 microsatellites; 10 out of 119 were rare (with frequencies lower than 0.01). Spanish cultivars can be used as references for those alleles for further studies since they are available in Germplasm banks. Triploid cultivars were quite frequent, 39 out of 140, with the highest number occurring in Galicia (29 cultivars). North Spain presented a high variability for apple according to heterozygosity levels. Microsatellites have provided useful information about the singularity of Spanish apple cultivars, revealed six groups of synonymies and five introgressions of commercial cultivars.     

Structure of the nematofauna in Spanish Mediterranean continental soils

We studied the nematofauna in cultivated Euvisols in the Spanish Central Region in terms of multivariate statistical relationships between nematode groups and environmental variables (habitat, hosts, soil lexture, and quantitative edaphic variables). Three large nematode associations were recognized, one group being characteristic of the region's rotational crops (Pratylenchus, Ditylenchus, Helicotylenchus, Tylenchorhynchus, Rotylenchus, other Dorylaimidae,Plectus, andTylenchus), a second group related to cereal monoculture and wild gramineae associated with bush formations (Heterodera, Criconemoides, Discolaimus, and other Rhabditidae), and a third group characteristic of uncultivated soils (Paratylenchus, Xiphinema, Hemicycliophora, Mononchus, Tripyla, andAlaimus).Paratylenchus andTylenchus species were shown to have an indicator value for certain edaphic properties, especially soil texture, and may be regulated by the clay content of the soil.     

Characterization of Italian and exotic Lathyrus germplasm for quality traits

The aim of the following work is to characterize quality traits (protein, ashes, 100 seed weight and ODAP content) of 117 accessions of Lathyrus, from either Italian or foreign countries. Significant differences among entries were estimated for all traits and accessions were classified into similar genetic groups. Principal component and hierarchical cluster analyses produced five different groups. In particular, the absence of a strong association among the investigated traits and their dominant independent roles in each separate principal component allows the achievement of a useful recombinant in breeding work. An interpretation of each cluster, based on the data obtained from the accessions, provides practical information to establish a subset of grass pea collection for further activities.     

Genetic diversity among Northwestern Argentinian cultivars of common bean (Phaseolus vulgaris L.) as revealed by RAPD markers

The genetic diversity of 10 commercial cultivars of common beans, developed in Northern Argentina was analyzed based on RAPD markers. Sixteen primers were assayed and among them only 4 showed polymorphisms. A similarity matrix was generated by applying three different association coefficients, Simple Matching, Jaccard and Dice. By the UPGMA method dendrograms were generated and also the principal coordinate analysis was performed. The similarity values found were higher than 40% suggesting that genetic diversity is low. Both cluster analysis and principal coordinates analysis associated commercial cultivars either to the Andean or the Mesoamerican gene pool.     

Correlations between camptothecin and related metabolites in Camptotheca acuminata reveal similar biosynthetic principles and in planta synergistic effects

Camptothecin (CPT), 9-methoxycamptothecin (9-MeO-CPT), and 10-hydroxycamptothecin (10-OH-CPT) are potent antineoplastic metabolites. We analyzed these metabolites in Camptotheca acuminata sampled from Germany and China, using LC-MS/MS and LC-ESI-HRMS/MS, coupled with chemometrics. Multivariate analysis revealed that fresh stems of C. acuminata from China had the highest comprehensive metabolite load. Significant positive correlations of CPT with 9-MeO-CPT and 10-OH-CPT were observed by Kruskal's multidimensional scaling and principal component analysis. Linear discriminant analysis and hierarchical agglomerative cluster analysis revealed that C. acuminata from China was separated from others. These positive correlations indicate that these metabolites are biosynthesized similarly and operate synergistically in planta.     

Narrow versus broad: sexual dimorphism in the wing form of western European species of the subgenus Avaritia (Culicoides,Ceratopogonidae)

While wing form is known to differ between males and females of the genus Culicoides, detailed studies of sexual dimorphism are lacking. In this study, we analyze sex-specific differences in the wing form of 5 species of the subgenus Avaritia, using geometric morphometrics and comparative phylogenetic methods. Our results confirm the existence of marked sexual dimorphism in the wing form of the studied species and reveal for the first time that while there is a shared general pattern of sexual shape dimorphism within the subgenus, sexual size dimorphism, and particular features of sexual shape dimorphism differ among species. Sexual shape dimorphism was found to be poorly associated to size and the evolutionary history of the species. The tight association of sexual shape dimorphism with aspect ratio suggests that the shape of the wing is optimized for the type of flight of each sex, that is, dispersal flight in females versus aerobatic flight in males. Moreover, the fact that interspecific shape differences are greater and more strongly associated to aspect ratio in males than in females might be indicating that in males the selective pressures affecting flight performance characteristics are more heterogeneous and/or stronger than in females among the studied species.