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Urban areas in arid and semiarid regions continue to face water supply and demand challenges ( St. Hilaire et al., 2008 ). Some of the drivers of these challenges include accelerated population growth and enhanced economic activity of urban areas

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Survivorship of high-quality landscape field-grown trees is a particular challenge as a result of differences in post-transplant recovery between species. During bare-root tree transplanting, a major part of the root system is severed, the tree is

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Florida citrus groves experience an average tree loss rate of 3% to 4% per year ( Muraro et al., 2005 ). Tree loss can be attributed to a number of factors, including, but not limited to, tristeza (citrus tristeza virus), blight (causal agent

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nursery production method and planting techniques on tree establishment in urban sites: Preliminary results J. Arboricult. 26 281 284 Gilman, E.F. 2004 Effects of amendments, soil additives, and irrigation on tree survival

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Conversion of wastewater to reclaimed water for crop irrigation conserves water and is an effective way to handle a growing urban problem: the disposal of wastewater. Water Conserv II is a large reclaimed water project developed by Orlando and Orange County, Fla., that presently irrigates ≈1900 ha of citrus. The project includes a research component to evaluate the response of citrus to irrigation using reclaimed water. Citrus trees in an experimental planting responded well to very high application rates of reclaimed water. Irrigation treatments included annual applications of 400 mm of well water, and 400, 1250, and 2500 mm of reclaimed water. The 2500-mm rate is excessive, and since disposal was of interest, this rate was used to determine if citrus could tolerate such high rates of irrigation. The effects of these treatments were compared on `Hamlin' orange [Citrus sinensis (L.) Osb.] and `Orlando' tangelo (C. paradisi Macf. × C. reticulata Blanco) combined with four rootstocks: Carrizo citrange [Citrus sinensis (L.) Osb. × Poncirus trifoliata (L.) Raf.], Cleopatra mandarin (C. reticulata Blanco), sour orange (C. aurantium L.), and Swingle citrumelo (C. paradisi × P. trifoliata). Growth and fruit production were greatest at the highest irrigation rate. Concentration of soluble solids in the juice was usually lowered by the highest irrigation rate, but total soluble solids per hectare were 15.5% higher compared to the 400-mm rate, due to the greater fruit production. While fruit soluble solids were usually lowered by higher irrigation, the reduction in fruit soluble solids observed on three of the rootstocks did not occur in trees on Carrizo citrange. Fruit peel color score was lower but juice color score was higher at the highest irrigation rate. Crop efficiency (fruit production per unit of canopy volume) was usually lower at the 2500-mm rate and declined as trees grew older. Weed cover increased with increasing irrigation rate, but was controllable. Irrigation with high rates of reclaimed water provided a satisfactory disposal method for treated effluent, benefited growth and production of citrus, and eliminated the need for other sources of irrigation water. Reclaimed water, once believed to be a disposal problem in Florida, is now considered to be one way to meet irrigation demands.

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rural, suburban, and urban landscapes could be differentiated by the percentage of trees and artificial surfaces. Two landscapes were covered by trees at 70% and 93%, and the sum of artificial surfaces was relatively low (<8%). These were categorized as

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agencies regulate for water use because of its high public visibility ( Devitt et al., 1995 ). Urban landscapes contribute as much as 20% of the fair market value of a residential property ( Council of Tree and Landscape Appraisers, 2003 ). So, the loss

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Ornamental peach (Prunus persica (L.) Batsch) is native to China. The ornamental value of peach is gaining popularity for its use in urban landscape and everyday gardens. However, the genetic relationship among ornamental peach cultivars is not clear, which limits the further studies of its molecular systematic. A sample of 51 cultivars of ornamental peach, originated from P. persica and Prunus davidiana, had been studied by using AFLPs. All samples were collected from China, Japan, and the US. A total of 275 useful markers between 75 to 500 base pairs were generated from 6 EcoRI/MseI AFLP primer combinations. Among them, 93% of bands were polymorphic markers. Total markers for each cultivar ranged form 90 to 140, and the average number of markers for each cultivar was 120. Two distinguished clad generated from PAUP-UPGMA tree. P. davidiana, as a species, was apparently an out-group to P. persica, which implied that P. davidiana was far away genetically from ornamental peach (P. persica). Within P. persica clad, 15 out of 17 upright ornamental peach cultivars in this study were grouped to one clad, which indicated cultivars that with upright growth habit had close genetic relationship. Five dwarf cultivars were grouped to one clad, with 81% bootstrap supported. The genetic relationships between these five dwarfs were much closer than any other cultivars, and showed that they probably derived from the similar gene pool. The results demonstrated that AFLP are powerful markers for revealing genetic relationships in ornamental peach. The genetic relationships among ornamental cultivars established in this study could help future ornamental peach germplasm identification, conservation, and new cultivars development.

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buildings and hotels, modern high rises (and so forth) with less vegetation, were represented as UBL ( Hartig and Staats, 2006 ). Urban settings that prominently portray natural components, such as trees, shrubs, flowers, weeds, grass, and water (all or

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are –36.4 °C and 38.9 °C, respectively. The average annual precipitation ranges from 43 to 969 mm, and the frost-free period ranges from 120 to 233 d. In Chaoyang, Liaoning, China, the cultivar is used as a local urban greening tree species. In

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