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Janice L. Stephens and Harrison G. Hughes

Isozyme analysis was used to characterize and identify 24 species, hybrids, and color variants of Alstroemeria, two plants of Leontochir ovallei, and one plant of Bomarea. A single technique was developed for the extraction of seven enzyme systems (PGM, PGI, 6-PGD, EST, ME, AAT, and LAP) that exhibited a high level of polymorphism. Between 11 and 18 of the species and hybrids could be identified uniquely for each of the first six enzyme systems. The final system, LAP, was tested on only 11 species and hybrids, and nine different patterns were identified. Using only three of the seven enzyme systems, it was possible to uniquely identify all of the species and hybrids investigated.

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Wei Zhou, Hong Wang, De-Zhu Li, Jun-Bo Yang and Wei Zhou

Luculia Sweet is a small shrubby genus containing three species and is a member of the family Rubiaceae (tribe Cinchoneae). All the species have compact pink or white tubular flowers contained in a tight inflorescence. The flowers are sweetly

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Douglas D. Archbold

Plants of a diverse collection of Fragaria clones from a range of native habitats representing F. chiloensis, F. virginiana, F. virginiana glauca, and F. vesca, were grown in a controlled environment at one of three day/night temperatures, 15/15, 23/15, or 31/15°C. Relative growth rate (RGR) and net assimilation rate (NAR) were estimated from plant leaf areas and total dry weights. At 23/15°C, the species mean RGR and NAR values were comparable although clones within species exhibited significant variation. At 15/15 and 31/15°C, RGR and NAR for species were lower than at 23/15°C. At 31/15°C, chiloensis and vesca mean values were reduced more than the others, to less than 50% the 23/15°C values. Also, NAR declined most for chiloensis, to 45% the 23/15°C value. At 15/15°C, virginiana had much higher RGR and NAR values than the other species, and its NAR mean value was greater than at 23/15°C. Although the species means would suggest that there are interspecific differences in temperature response, intraspecific variability was also large. Thus, classifying Fragaria species by temperature response may be an over-generalization.

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Natalia R. Dolce, Ricardo D. Medina and María T. González-Arnao

Ilex L. (Aquifoliaceae) is the largest genus of woody dioecious plants, with at least 600 species ( Galle, 1997 ; Loizeau and Spichiger, 2004 ). Although the genus is almost cosmopolitan, most species occur in mesic subtropical or tropical

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Angela R. Davis, Amnon Levi, Antonia Tetteh, Todd Wehner, Vincent Russo and Michel Pitrat

in virulence against cucurbit species, and in their sensitivity to fungicides ( Bertrand, 1991 ; Epinat et al., 1993 ; McGrath, 2001a , 2001b ). Only one species, P. xanthii , has been reported on watermelon in the United States. Using

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Nathan C. Phillips, Steven R. Larson and Daniel T. Drost

Efficient propagation of native intermountain plant species for rangeland restoration and other commercial uses requires some basic knowledge about natural genetic diversity in the landscape ( Adair et al., 2006 ; Monsen and Shaw, 2001 ). The

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Patricia Quesada and Frank B. Matta

Two species of Passiflora, P. edulis f. edulis (purple passion fruit) and P. edulis f. flavicarpa (yellow passion fruit), and P. incarnata (maypop), were evaluated for acclimation and cold hardiness, using differential thermal analysis, electrolyte leakage and the tetrazolium stain test. The two species showed the capacity to acclimate several degrees during the evaluation period and the three tests gave similar lethal temperatures for the two species; –9C to –10C for yellow passion fruit, –10C to –12C for purple passion fruit and –11C to –13C for maypop. Purple and yellow passion fruit were also assayed for survival after a freeze-thaw cycle, using a tissue culture regeneration technique called “feeder plate”. Yellow passion fruit did not show the capacity to regenerate at any of the temperatures used (0, –3, –6C). Purple passion fruit showed callus formation even at the lowest temperature (–6C).

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Dario J. Chavez, Thomas G. Beckman and José X. Chaparro

sometimes changed the previously published species groupings and classifications. Prunus classifications and discrepancies were well summarized by Bortiri et al. (2001) , with Rehder’s (1940) classification being recognized as the most widely used and

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Jianjun Chen, Lijia Li and Ying Wang

Epimedium L. (2 n = 2 x = 12), referred to as yin yang huo in Chinese, belongs to the basal eudicot plant family, berberidaceae. The genus of Epimedium is composed of more than 50 species ( Stearn, 2002 ), most of which are widely distributed

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Jennifer L. Parke, Neelam R. Redekar, Joyce L. Eberhart and Fumiaki Funahashi

Diseases caused by Phytophthora species are among the most damaging to greenhouse and nursery-grown horticultural crops ( Jones and Benson, 2001 ; U.S. Department of Agriculture, 2009 ). These pathogens cause damping-off diseases, root rot, stem