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L.J. Grauke, Muhammad J. Iqbal, Avutu S. Reddy, and Tommy E. Thompson

A microsatellite-enriched library was developed from `Halbert', a native pecan [Carya illinoinensis (Wangenh.) K. Koch] selection from Coleman County, Texas. A genomic library enriched for simple sequence repeats (SSR) containing 6144 clones was archived in 384 well plates for screening. In total, 439 clones were identified after Southern hybridization using di- and tri-nucleotide repeats as probes. In total, 125 positive clones were sequenced and primers were designed for 24 repeats. The SSR markers chosen for analysis include di-(CT and GA) and tri-nucleotide repeats (CTT, GAA and GAT). Of the 24 primer pairs tested, 19 successfully amplified microsatellites from `Halbert'. DNA was isolated from 48 pecan and hickory accessions selected to strategically represent the genetic diversity of the National Clonal Germplasm Repository (NCGR) Carya collections. The 19 SSR primers that produced good amplification products in `Halbert' were used to evaluate the collection, with 11 revealing polymorphism. The number of fragments amplified with different primer combinations ranged from 4 to 32 in the 48 genotypes tested. Evaluation of the data confirms the utility of the microsatellites in delimiting known relationships.

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Ying Wang, Gregory L. Reighard, Desmond R. Layne, Albert G. Abbott, and Hongwen Huang

Pawpaw (Asimina triloba) produces the largest fruit native to the United States. Six linkage groups were identified for A. triloba using the interspecific cross [PPF1-5 (A. triloba) × RET (A. reticulata Shuttlw. ex Chapman)], covering 206 centimorgans (cM). A total of 134 dominant amplification fragment length polymorphism (AFLP) markers (37 polymorphic and 97 monomorphic) were employed for estimating the genetic diversity of eight wild populations and 31 cultivars and advanced selections. For the wild populations, the percentage of polymorphic loci over all populations was 28.1% for dominant markers and Nei's genetic diversity (He) were 0.077 estimated by 134 dominant markers. Genetic diversity and the percentage of polymorphic loci estimated using only polymorphic dominant AFLPs were 0.245 and 79%, respectively, which are comparable with other plant species having the same characteristics. Estimated genetic diversity within populations accounted for 81.3% of the total genetic diversity. For cultivars and advanced selections, genetic diversity estimated by 134 dominant markers was similar to that of wild pawpaw populations (He = 0.071). Thirty-one cultivars and advanced selections were delineated by as few as nine polymorphic AFLP dominant loci. Genetic relationships among wild populations, cultivars and advanced selections were further examined by unweighted pair group method with arithmetic mean (UPGMA) of Nei's unbiased genetic distance. The genetic diversity estimated for wild populations using the clustered polymorphic markers was lower than the result estimated using the nonclustered polymorphic markers. Therefore, this study indicates that the number of sampled genomic regions, instead of the number of markers, plays an important role for the genetic diversity estimates.

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Barbara C. Hellier

independent nations that split from the Soviet Union when it dissolved in 1991, the area became accessible to U.S. scientists. The other, and more important, reason is that this region is rich in plant biodiversity. Conservation International recognizes two

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S. Christopher Marble and Stephen H. Brown

.E. Benton, N. Hiebert, R. Lu, S. Killeffer, T. 2008 The invasive species assessment protocol: A tool for creating regional and national lists of invasive nonnative plants that negatively impact biodiversity Invasive Plant Sci. Manag. 1 36 49

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Michelle M. Wisdom, Michael D. Richardson, Douglas E. Karcher, Donald C. Steinkraus, and Garry V. McDonald

bulbs can persist in zoysiagrass ( Zoysia japonica Steud.) and bermudagrass ( Cynodon dactylon ) in transition zone environments, providing color and biodiversity to dormant turfgrass situations. However, both studies examined a small number of bulb

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Roland Ebel

as forest degradation, erosion, floods, land sinking, pollution of soil and water, reduced water retention and infiltration, and a loss of biodiversity. Farmers now deal with increasing pest populations and changes in the regional climate ( Torres et

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Joseph Thomas and Matthew Taylor

reduces invasive plant pressure and improves biodiversity. Units Literature cited Catanzaro, C.J. Skroch, W.A. Burton, J.D. 1993 Resistance of selected ornamental grasses to graminicides Weed Technol 7 2 326 330

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Lucy K. Bradley, Bridget K. Behe, Natalie R. Bumgarner, Charlotte D. Glen, Joseph L. Donaldson, Ellen M. Bauske, Sheri Dorn, and Gail Langellotto

“Considerations to Quantify the Economic Contributions and Benefits of Consumer Gardening.” To present potential examples for monetizing the many benefits of CH, such as health, well-being, and biodiversity, Ms. Charlotte Glen reviewed the current state of

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Elina Yankova-Tsvetkova, Ivanka B. Semerdjieva, Rozalia Nikolova, and Valtcho D. Zheljazkov

biology characterized the studied species as a sexually reproducing taxa that would guarantee the stability of size of their populations. This is especially important for the conservation of these species as part of biodiversity of the Bulgarian flora

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Lamprini Tassoula, Maria Papafotiou, Georgios Liakopoulos, and Georgios Kargas

greenhouse gas emissions and ambient noise, neglect of the built environment, and low biodiversity ( European Commission, 2007 ). Green roofs can contribute to addressing these challenges. A number of reviews and books ( Berardi et al., 2014 ; Dunnett and