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T.M. Waliczek, P. Logan, and J.M. Zajicek

The main objective of this study was to investigate the impact of an outdoor environmental program, Math and Science in the Outdoor Classroom, on elementary grade students' creative and critical thinking, and attitudes toward math and science. Math and Science in the Outdoor Classroom is an on-campus nature program in Santa Fe, N.M. Students participated in half-day programs focusing on topics such as water, insects, soil, and weather. Twenty-one teachers from five schools volunteered 175 second through sixth graders to participate in the program and research study. Surveys were administered to students, teachers, and volunteers after completion of the program. Interview data was analyzed using QSR NUD*IST (Nonnumerical Unstructured Data Indexing Searching and Theory-building) computer-assisted qualitative data analysis system to examine respondents' perceptions of the program using Bloom's taxonomy as a theoretical framework. Results indicated that students not only learned math and science at the lower levels of Bloom's taxonomy, but were also thinking at the higher levels of synthesis and evaluation within the framework.

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Hongwen Huang, Zuozhou Li, Jianqiang Li, Thomas L. Kubisiak, and Desmond R. Layne

Phylogenetic relationships within the Actinidia were investigated using randomly amplified polymorphic DNA (RAPD) markers. DNAs from 40 taxa, including 31 species encompassing all four sections and four series of the traditional subdivisions within the genus, were amplified using 22 preselected 10-mer oligonucleotide primers. A total 204 DNA bands were scored across the 40 taxa, of which 188 (92%) were polymorphic. A wide range of genetic similarity was observed among the taxa (0.13 to 0.61). The average similarity between varieties of the same species was 0.54, and between different species was 0.28, respectively. Although the phylogenetic analysis revealed a clear indication that section Leiocarpae was a monophyletic group, subdivisions of the other three traditional sections were poorly supported. The UPGMA phenogram showed that the majority of the species clustered into geographic subgroups in accordance with their natural distribution (the Yangtzi River, southeastern China, southern China and southwestern China). The intrageneric subdivisions of Actinidia appeared to be difficult, but some subdivisions could be explained by the geographic distribution of the species, particularly for species of Liang's sections of Maculatae and Stellatae. The phylogenetic relationships among several species with previous taxonomic uncertainty are also discussed on the basis of the RAPD data. The results of this study supplement our previous understanding of the Actinidia taxonomy based solely on morphological characters.

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Randall P. Niedz, Michael G. Bausher, and C. Jack Hearn

leaf and seed glycoproteins were detected after sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and electroblotting onto polyvinylidene difluoride (PVDF) membrane when probed with biotinylated lectin at 1 μg·ml-1. Four lectins representing three carbohydrate-binding groups were used as probes. A preformed avidin-biotin-complex (ABC) was used to detect the glycoprotein-bound lectins and resulted in dark bands and little background staining. Concanavalin A (ConA) and wheat germ agglutinin (WGA) resulted in the darkest-staining bands. The four Citrus spp. and one related species studied had unique seed glycoprotein profiles when probed with ConA and WGA. This procedure might be useful in clarifying citrus taxonomy, providing genetic markers, and in physiological studies involving glycoproteins.

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M. M. Thompson

Seeds and herbarium specimens of 47 accessions from 11 Rubus taxa native to the Andean Region of Ecuador were collected in October and November 1990 and deposited at the USDA/ARS Germplasm Repository in Corvallis, OR. Plants will be grown from these seeds and evaluated for taxonomic identity and potential breeding value. Characteristics of the plants will be discussed. Taxa obtained include: R. adenothallos Focke, R. acanthophyllus Focke, R. bogotensis Kunth, R. coriaceus Poiret, R. glabratus H.B.K., R. glaucus Benth., R. robustus C. Presl., R. roseus Poiret, R. urticifolius Poiret. These taxa will contribute unique genes to the improvement of Rubus crops by breeders throughout the world. Seeds may be requested from the curator, USDA/ARS NCGR-Corvallis.

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R. A. Criley and S. Lekawatana

More than three dozen species of Heliconia have entered the cut flower trade since the expanded interest in bold tropical cut flowers began in the early 1980s. Most were wild-collected originally with little information on their habitats or season of bloom. A natural flowering season for some species can be found in the taxonomic literature, but it may be influenced locally by rainfall and drought periods as well as by photoperiod and therefore not reliable in indicating production periods in Hawaii. Sales records from 1984 through 1990 or several heliconia growers on Oahu reflected not only the quantities produced but also the time and duration of the blooming season. Such information is helpful in coordinating with the flower markets. Heliconia species of commercial interest with strong seasonal flowering periods are noted: angusta, bihai, caribaea, caribaea X bihai, collinsiana, farinosa, lingulata, rostrata, sampaioana, stricta, subulata, wagneriana.

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Tommy E. Thompson, Samuel D. Senter, and L.J. Grauke

Pollen from five cultivars of pecans [Carya illinoinensis (Wangenh.) K. Koch] was analyzed for cytoplasmic lipid classes and constituent fatty acids. Lipid classes in all cultivars included free fatty acids, triglycerides, and the phosphatide of inositol, serine, choline, glycerol, and ethanolamine. Triglycerides were the predominant class of lipids in all cultivars analyzed. Gas chromatography and mass spectral analysis were used to identify and quantify the fatty acids, which included palmitic, stearic, oleic, linoleic, and linolenic. Quantities of individual and total fatty acids varied greatly and were influenced significantly by cultivar, year, and location, as well as by interactions of main effects The percent composition of individual fatty acids was remarkably stable, despite wide variation in quantities of fatty acids. Therefore, pollen fatty acid ratios may be a valuable measure of taxonomic relationship across Carya sp. Total fatty acids varied from 2.53% to 0.25% of dry weight. Variability in stored energy in the form of lipids may affect orchard production.

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Rina Kamenetsky and Jacob Blaustein

The annual life cycle and development of the monocarpic shoot of some ornamental Allium species from Central Asia and the Mediterranean area have been followed from the time of meristem dome initiation in the axil of a mother plant leaf, through formation of scale, leaf and flower primordia. There are three periods of meristem activity from apex initiation to flower formation. Detailed analysis of inflorescence development has been carried out by Scanning Electronic Microscope (SEM). The life span of the Allium monocarpic shoot can be as long as 18 months. Climatic variations between Central Asian and Mediterranean areas lead to differences in the time of leaf sprout and flowering of species from the same taxonomic group. The principal mechanism of floral initiation is similar for species from both areas. Knowledge of the structure and development of the shoot will be useful for improvement of an optimal program of ornamental Allium cultivation.

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J. Lu, Z. Liu, and Y. Zheng

Genetic relationships among 42 grape accession of at least 15 species were estimated and compared using RAPD and isozyme techniques. These accessions were either hybrids or wild collections of the Asiatic species, the American species, the European grape (V. vinifera), and muscadine grape (V. rotundifolia). A total of 196 RAPD fragments were generated from twenty 10-mer primers. The pairwise similarities among the accession ranged from 0.46 to 0.94. A dendrogram was generated based on the RAPD similarity coefficients. Species/accessions were basically grouped together in accordance with their geographic origins. The similarities and dendrogram resulted from the RAPD analysis were consistent with the ones generated from the isozyme data, and also consistent with the known taxonomic information. This result suggest that the RAPD method, like isozyme, is an useful tool for studying grape genetic relationship/diversity and origination.

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P. Boccacci, A. Akkak, D. Torello Marinoni, G. Bounous, and R. Botta

Microsatellite or simple sequence repeat (SSR) markers show many characteristics of the ideal molecular marker, and recent studies have shown that loci developed in one species may allow analysis in taxonomically related species. In this study, 52 primer pairs developed in two oak species—Quercus robur L. and Quercus petraea (Matt.) Lieb.—were used to amplify DNA of 5 chestnut cultivars; 28 of them yielded amplicons and 12 polymorphic loci were selected and used to fingerprint 12 european chestnut (Castanea sativa Mill.) cultivars grown in the Piedmont region of northwestern Italy. The number of alleles per locus ranged from 3 to 8, mean expected heterozygosity was 0.592 (range: 0.288 to 0.868), and mean observed heterozygosity was 0.667 (range: 0.333 to 1.000). The results demonstrate the usefulness of some SSR markers isolated in Quercus for the fingerprinting and genetic mapping of Castanea cultivars.

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Dapeng Zhang and Wanda Collins

To understand the prospects of applying the RAPD technique to assay genetic diversity in Ipomoea, four species (I. batatas, I. trifida, I. triloba, and I. ×leucantha) were analyzed for RAPD molecular markers. Six accessions of each species were used. Significant RAPD polymorphisms were detected within each species. Of 20 primers used, nine produced clear scorable polymorphic bands. The number of polymorphic bands produced per primer ranged from two to nine. Pair-wide genetic distance was calculated based on “band sharing”. The SAS-CLUSTER procedure was used to build a hierarchical species dendrogram. The four species were clearly separated by the clustering, which agrees with their existing taxonomic relationship. This study shows that RAPD analysis can be a powerful tool for identifying duplicates of germplasm acessions and for assessing genetic diversity. The procedures are relatively inexpensive and easy to perform and could be valuable in preliminary assessment of field genebank collections to separate species and indicate duplications in collected material.