Amplified Fragment Length Polymorphism (AFLP) Provides Molecular Markers for the Identification of Caladium bicolor Cultivars

Caladiums are popular ornamental plants that have not been wellstudied at the molecular level. Identification of species withinthe genus Caladium (Araceae) has been based primarily on morphology.However, the lack of comprehensive references makes identificationof Caladium cultivars extremely difficult. Amplified fragmentlength polymorphism (AFLP) analysis using 17 primer combinationswas carried out on two species of Caladium (C. bicolor and C.schomburgkii), including six cultivars of C. bicolor. Resultsshowed that AFLP can be used to distinguish these two speciesby their unique and different banding patterns. Unweighted PairGroup Method using Arithmetic Averages (UPGMA) permitted clusteranalysis of data from 17 selected primer combinations on sixcultivars of C. bicolor and one cultivar ofC. schomburgkii .It showed that closely related species can clearly be differentiatedand that genetic difference between cultivars can also be established.Unique AFLP molecular markers were detected for all the C. bicolorcultivars used. The use of AFLP has potential for preciselycharacterizing and identifying particular caladium cultivarsas well as for the registration of new cultivars. It will alsobe useful in future breeding programmes and systematics studies.Copyright 1999 Annals of Botany Company Araceae, Caladium species and cultivars, AFLP DNA fingerprinting, diversity, AFLP markers.     

Genetic diversity patterns in Curcuma reflect differences in genome size

The relationships between genome size and the systematic and evolutionary patterns in vascular plants are equivocal, although a close relationship between genome size and evolutionary patterns has been previously reported. However, several studies have also revealed the dynamic nature of genome size evolution and its considerable ‘ups’ and ‘downs’. Thus, in this study, the phylogenetic relationships among three previously revealed genome size groups and among species of the highly polyploid genus Curcuma were evaluated using AFLP. Our results suggest two main lineages within Indian Curcuma reflecting evolution of genome size. The first one includes hexaploids and higher polyploids of the previously recognized genome size group I, and the second one includes mainly hexaploids of genome size groups II and III. Within genome size group I, relationships among species seem to be influenced by reticulate evolution and higher polyploids are likely to be of allopolyploid origin. Reproductive systems in Indian Curcuma vary considerably among ploidy levels and these differences considerably affect morphological and genetic variation. In general, clonally reproducing species are expected to exhibit low genotypic diversity, but, at the same time, species of allopolyploid origin are expected to maintain higher levels of heterozygosity compared with their progenitors. We investigated intra‐populational genetic variability in Curcuma spp. to evaluate whether mode of reproduction or ploidy represent the main factor influencing the degree of genetic diversity. We found that hexaploid species exhibited significantly higher genetic diversity than higher polyploids (9x, 15x). Our results suggest that this genetic diversity pattern is largely influenced by the mode of reproduction, as higher polyploids reproduce exclusively vegetatively, whereas hexaploids reproduce mainly sexually. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 388–401.     

华北京津冀地区兽类新纪录——香鼬

An adult weasel was photographed in September 2019 during a camera-trapping survey in the Haituo-Songshan mountain area of Beijing. This species was identified as the mountain weasel (Carnivora;Mustelidae;Mustela altaica), a small mustelid native to the mountains of East and Central Asia, found on the Qinghai-Tibet Plateau, and in some high-altitude regions of northern and southwestern China. However, the documented localities of M. altaica nearest to Beijing are from Shanxi and Inner Mongolia, while none was reported from Beijing or its adjacent Tianjin and Hebei. This finding therefore added a new record of mammalian species to the Beijing-Tianjin-Hebei Metropolitan Region and the Yanshan Mountains, and also expanded the known range of M. altaica in China. It revealed the likely underestimated species richness in suburban Beijing and highlighted the importance of systematic biodiversity monitoring and conservation in urban ecosystems.     

澳门地区鸟类生境的景观格局

以2006年澳门地区TM遥感图像为主要数据源,在RS、GIS技术支持下,根据与鸟类活动密切相关的生境特征,利用Fragstats 3.3分析生境格局的基本特征和地区差异,讨论了景观的破碎化程度、连通性、景观异质性等对鸟类有重要影响的生境因素。结果显示：澳门的鸟类生境格局在澳门半岛和路氹离岛差异较大,与其城市化的程度有较高的相关性;澳门半岛以建设用地为基底,绿地数量少且破碎,景观多样性和异质性较低;路氹离岛以林地为基底,中部填海区的建设用地和裸地以大斑块存在,生境类型分布较澳门半岛均匀,连通性较佳,总体鸟类生境格局优于澳门半岛。澳门半岛有鸟类72种,其中陆生鸟类48种、水鸟24种;路氹离岛有鸟类146种,其中陆生鸟类94种、水鸟52种。对鸟类调查数据分析发现,生境格局对于鸟类物种数、多样性和均匀度方面均有一定影响。澳门在珠江口地区候鸟迁徙和湿地保护方面的重要性较高,在城市发展过程中应重视提高景观多样性和异质性,保护重要鸟类生境,以适应不同鸟类对各种生境的需求。     

The occurrence and effect of a protozoan parasite, Ophryocystis elektroscirrha (Neogregarinida: Ophryocystidae) on overwintering monarch butterflies, Danaus plexippus (Lepidoptera: Danaidae) from two California winter sites

Abstract.

• 1 Monarch butterflies, Danaus plexippus, from two overwintering populations, were found to have Ophryocystis elektroscirrha spores on their scales at rates between 53% and 68%. The frequency of butterflies with O.elektroscirrha spores remained about the same between sites and throughout the winter.
• 2 The spores, recovered from all parts of the body of the butterfly, were most numerous on the abdomen, particularly near the posterior third.
• 3 Butterflies with spores survived as long as those without detectable spores at 10.1°C ±0.4 SE and 78.3% r.h. ±0.6SE. Insects with spores held at 19.4°C ±0.4SE and 44.9% r.h. ±1.5SE showed a significantly higher rate of moisture loss and survived a shorter period than monarch butterflies without detectable spores.

     

Isolation and characterization of six polymorphic microsatellite loci in Aspergillus niger

Certain strains of Aspergillus niger produce ochratoxin A in food and in animal feeds. Six polymorphic microsatellite markers suitable for population analysis were developed for A. niger through screening published sequences for microsatellite repeats. Polymorphism was evaluated for 28 isolates of A. niger, including toxigenic strains. Loci displayed six to 13 alleles. Investigation of cross‐species amplifications with Aspergillus carbonarius and Aspergillus japonicus showed limited success.     

Chloroplast DNA phylogeography suggests a West African centre of origin for the baobab, Adansonia digitata L. (Bombacoideae, Malvaceae)

The African baobab ( Adansonia digitata L.) is an emblematic, culturally important, and physically huge tropical tree species whose natural geographical distribution comprises most of tropical Africa, but also small patches of southern Arabia, and several Atlantic and Indian Ocean islands surrounding the African continent, notably including Madagascar. We analysed the polymerase chain reaction–restriction fragment length polymorphism of five chloroplast DNA fragments obtained from 344 individuals of A. digitata collected from 74 populations covering the entire extant distribution range of the species. Our goal was to reconstruct the phylogeographical history of the species and, if possible, to identify its centre of origin, which has been a subject of controversy for many decades. We identified five haplotypes whose distribution is clearly geographically structured. Using several species of Adansonia and of closely related genera as outgroups, the haplotypes showed a clear phylogeographical pattern of three groups. Two are phylogenetically related to the outgroup taxa, and are distributed in West Africa. The third group is substantially more differentiated genetically from outgroup species, and it corresponds to southern and eastern Africa, Arabia and the Indian Ocean islands, including Madagascar. According to our results, the tetraploid A. digitata , or its diploid progenitor, probably originated in West Africa and migrated subsequently throughout the tropical parts of that continent, and beyond, by natural and human-mediated terrestrial and overseas dispersal.     

The Influence of Temperature and Soil Water Deficit on the Development and Morphology of Groundnut (Arachis hypogaea L.)

The rate/temperature relation of several developmental processesin groundnut was examined in a suite of temperature-controlledglasshouses maintained at mean air temperatures of 19, 22, 25,28 and 31 °C. The sensitivity of the various processes tosoil water deficit was also examined. When the relation between rate and temperature was linear, measurementswere analysed in terms of thermal time (°Cd) and an extrapolatedbase temperature (T_b) at which the rate was zero. T_b was conservative(10 °C) for leaf appearance, branching, flowering, peggingand podding. A higher value of T_b for seedling emergence (16°C) was probably an artifact caused by soil pathogens. Leafappearance and branching were more sensitive to soil water deficitthan the other processes examined. Key words: Temperature, Soil water deficit, Development, Groundnut