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We mapped DNA polymorphisms generated by 41 sets of Simple Sequence Repeat (SSR) primers, developed independently in four laboratories. All primer sets gave polymorphisms that could be located on our `White Angel' x `Rome Beauty' map for apple [Malus sylvestris (L.) Mill. Var. domestica (Borkh.) Mansf.]. The SSR primers were used to identify homologous linkage groups in `Wijcik McIntosh', NY 75441-58, `Golden Delicious', and `Liberty' cultivars for which relatively complete linkage maps have been constructed from isozyme and Random Amplified Polymorphic DNA (RAPD) markers. In several instances, two or more SSRs were syntenic, and except for an apparent translocation involving linkage group (LG) 6, these linkages were conserved throughout the six maps. Twenty-four SSR primers were consistently polymorphic, and these are recommended as standard anchor markers for apple maps. Experiments on a pear (Pyrus communis L.) population indicated that many of the apple SSRs would be useful for mapping in pear. However some of the primers produced fragments in pear significantly different in size than those in apple.

Genes encoding lysozyme (T4L) from T4 bacteriophage and attacin E (attE) from Hyalophora cecropia were used, either singly or in combination, to construct plant binary vectors, pLDB15, p35SAMVT4, and pPin2Att35SAMVT4, respectively, for Agrobacterium-mediated transformation of `Galaxy' apple, to enhance resistance to Erwinia amylovora. In these plasmids, the T4L gene was controlled by the cauliflower mosaic virus 35S promoter with duplicated upstream domain and the untranslated leader sequence of alfalfa mosaic virus RNA 4, and the attE gene was controlled by the potato proteinase inhibitor II (Pin2) promoter. All transgenic lines were screened by polymerase chain reaction (PCR) for T4L and attE genes, and a double-antibody sandwich enzyme-linked immunosorbent assay for neomycin phosphotransferase II. Amplification of T4L and attE genes was observed in reverse transcriptase-PCR, indicating that these genes were transcribed in all tested transgenic lines containing each gene. The attacin protein was detected in all attE transgenic lines. The expression of attE under the Pin2 promoter was constitutive but higher levels of expression were observed after mechanical wounding. Some T4L or attE transgenic lines had significant disease reduction compared to nontransgenic `Galaxy'. However, transgenic lines containing both attE and T4L genes were not significantly more resistant than nontransgenic `Galaxy', indicating that there was no in planta synergy between attE and T4L with respect to resistance to E. amylovora.

The genetic basis of resistance to apple scab [Venturia inaequalis (Cke.) Wint.] in the Russian apple seedling R12740-7A (Malus Mill. sp.) was investigated. Segregation ratios obtained in crosses with susceptible cultivars suggested that at least two genes were involved, and three foliar resistance reactions (chlorotic, stellate necrotic, and pit type) were observed after inoculation. DNA markers were identified for both the stellate necrotic (Vr) and pit type (no locus designation, Vx suggested) resistance phenotypes. Comparison of resistance phenotypes with marker segregation demonstrated that only two major dominant genes were present in R12740-7A, one producing the stellate necrotic lesion and the other the pit-type lesion. The chlorotic lesion could be attributed to either unclear expression of the resistance phenotype or to susceptible genotypes not contracting the disease. These markers along with a previously published marker for Vf were used to analyze inheritance of resistance in a Vr × Vf cross in advanced breeding material. The markers identified successfully all susceptible progeny, as well as apparent escapes and individuals possessing both Vf and Vr. Thus, the markers should be useful in future screening of segregating progeny and in the pyramiding of scab resistance genes in new cultivars.

This paper invokes a theoretical model of immigrant membership exclusion to assess the political integration of second-generation Mexican Americans. Specifically, we examine the extent to which the migration status of parents, especially mothers, is associated with the political engagement, community engagement, and voting registration of their adult offspring. In each type of engagement, respondents whose mothers have remained unauthorized show lower overall levels of political incorporation. The effect is indirect in that it is mediated by the respondents’ educational level, in keeping with prior research showing that persistent unauthorized status by mothers reduces the years of schooling of children. This study thus contributes to the literature finding that the unauthorized status of parents has repercussions for the overall integration of their offspring.

Genes from the biocontrol fungus Trichoderma atroviride encoding the antifungal proteins endochitinase or exochitinase (N-acetyl-β-D-hexosaminidase) were inserted into ‘Marshall McIntosh’ apple singly and in combination. The genes were driven by a modified CaMV35S promoter. The resulting plants were screened for resistance to Venturia inaequalis, the causal agent of apple scab, and for effects of enzyme expression on growth. Disease resistance was correlated with the level of expression of either enzyme when expressed alone but exochitinase was less effective than endochitinase. The level of expression of endochitinase was negatively correlated with plant growth while exochitinase had no consistent effect on this character. Plants expressing both enzymes simultaneously were more resistant than plants expressing either single enzyme at the same level; analyses indicated that the two enzymes acted synergistically to reduce disease. Selected lines, especially one expressing low levels of endochitinase activity and moderate levels of exochitinase activity, were highly resistant in growth chamber trials and had negligible reduction in vigor relative to control plants. We believe that this is the first report of resistance in plants induced by expression of an N-acetylhexosaminidase and is the first report of in planta synergy between an exochitinase and an endochitinase.

A cDNA clone of the gene encoding attacin was used to construct three plasmid binary vectors in which attE was controlled by the cauliflower mosaic virus 35S promoter with duplicated upstream B domain (35S) (p35SAtt), 35S with the untranslated leader sequence of alfalfa mosaic virus RNA 4 (AMV) (p35SAMVAtt), and 35S with AMV and the signal peptide of pathogenesis-related protein 1b from tobacco (SP) (p35SAMVSPAtt), respectively. These plasmids and pLDB15 containing attE under the control of the potato proteinase inhibitor II (Pin2) promoter were used in Agrobacterium-mediated transformation of the apple scion cultivar `Galaxy' and the apple rootstock M.26 to enhance resistance to Erwinia amylovora, the bacterium that causes fire blight. The mean attacin content of transgenic lines containing attacin with AMV was three times higher than lines without AMV. Northern blots suggested that AMV functioned in apple as it does in other plant species by enhancing translation of attE mRNA. Transgenic `Galaxy' lines with attacin fused to SP had lower attacin content than lines without SP. In vitro assays indicated that attacin was partially degraded in the intercellular fluid of apple leaves. However, transgenic `Galaxy' lines transformed with attacin fused to SP had significantly less disease than those without SP suggesting that intercellularly secreted attacin is more effective in reducing E. amylovora infection than intracellularly localized attacin. A negative correlation was observed between attacin content and disease resistance in Pin2Att transgenic `Galaxy' lines following inoculation with E. amylovora, suggesting that attacin enhances resistance to fire blight.

A gene encoding attacin E, an inducible antibacterial protein from Hyalophora cecropia pupae, was cloned into the pRSETB Escherichia coli expression vector under the control of the T7 promoter. The resulting vector, pRSETBAtt, produced a fusion protein in E. coli JM109 of attacin with an N-terminal peptide containing six histidine residues in tandem. Fusion attacin was purified from cell lysates (6–9 mg l−1) by Ni2+-Sepharose affinity chromatography. Purified attacin protein was used as antigen to produce polyclonal antibody to detect attacin expressed in transgenic apple. Antibody capture immunoassay and immunoblot assays indicated that polyclonal antisera derived from fusion attacin had specific immunoreaction against attacins in the hemolymph of immunized pupae and attacin expressed in transgenic apple lines similar to native attacin antisera. Attacin expressed in transgenic apple could be quantified using immunoblot assays with the fusion attacin polyclonal antibody.

Bulked segregant analysis was used to identify RAPD markers that display tight linkage to the Vf gene in apple (Malus sp.) that confers resistance to five races of apple scab [Venturia inaequalis (Cke.) Wint.]. We identified several new RAPD markers linked to Vf. The most tightly linked marker in the test population, S52500, was cloned and sequenced. A linkage map of the Vf region was developed using these markers, RAPD markers previously described by other laboratories, and the isozyme locus Pgm-1. An assay was developed for Vf by multiplexing the two markers closely flanking the Vf locus. This assay has a theoretical `escape' value (discarding a resistant plant) of 3% and an error rate (selection of a susceptible plant) of 0.02%.

Random amplified polymorphic DNAs (RAPDs) were used in combination with a double pseudo-testcross mapping strategy to estimate the position and effects of quantitative trait loci (QTLs) for traits influencing juvenile tree growth and development in two apple cultivars. The mapping population consisted of 172 F1 trees from a cross between the columnar mutant ‘Wijcik McIntosh’ and a standard form disease-resistant selection NY 75441-58. Significant associations were found between markers and height increment, internode number, internode length, base diameter increment, base diameter after 9 years of growth, branch number, and leaf break. The number of genomic regions associated with each trait varied from one to eight. The amount of variation explained by linear regression on individual marker loci (R2) ranged from 3.9 to 24.3%, with an average of 7%. Multiple regression using markers for each putative QTL explained from 6.6 to 41.6% of the phenotypic variation, with an average value of 24.3%. A large number of traits had significant variation associated with the map position of the dominant columnar gene, Co. QTL stability over years was estimated by comparing the locations of putative QTLs for traits measured in multiple years. The majority of genomic regions were associated with a trait in only a single year, although regions associated with a trait in more than 1 year were also detected. The limitations of dominant markers and an outbred mapping pedigree for QTL analysis are discussed.

Primers of arbitrary sequence were screened by bulked segregant analysis to identify DNA fragments linked to Vm, a gene conferring resistance to apple scab (Venturia inaequalis). A 687-bp fragment generated by 10-base primer OPB12 gave tight linkage (no recombinants) in a population of 59 individuals from the cross 'Empire' x NY74828-12. The DNA fragment was sequenced, and two specific primers were generated to produce a STS marker for Vm. These primers were used in New Zealand to screen a second population of 180 individuals from a different cross. In this population, the marker displayed 8% recombination with Vm. A survey of Malus germplasm indicated that the marker was present in relatively few accessions, but was present in all known sources of Vm, including the cultivar Murray. However, none of the other sources of scab resistance, nor any other commercial cultivar, displayed the OPB12 fragment. These results suggest that this marker should be useful for the pyramiding of scab resistance genes in cultivated apple and, perhaps, for identifying other accessions in the Malus germplasm collection that possess Vm.Key words: sequence tagged site, gene pyramiding, Malus, Vm.

Fruit from seedlings selected from a population obtained by crossing superficial scald-resistant `White Angel' and superficial scald-susceptible `Rome Beauty' apple (Malus ×domestica Borkh.) were used to investigate the role of oxidative processes in the development of superficial scald. Selections were identified for study based on fruit coloration and scald susceptibility. Plant material had one of the following three physiognomies: 1) red-skinned fruit resistant to scald; 2) red-skinned fruit susceptible to scald; and 3) yellow-skinned fruit susceptible to scald. The concentrations of α-farnesene, conjugated triene (CT) species, hydrogen peroxide (H2O2), thiobarbituric acid-reactive substances, carbonyl groups, and the activities of superoxide dismutase, guaiacol-peroxidase, and catalase were measured at harvest and during 0.5 °C storage. Relationships were poor between scald susceptibility and α-farnesene and its oxidation products, CT258, CT281, and the CT258/CT281 ratio. Tissue concentrations of H2O2 were lower in scald-resistant than in scald-susceptible fruit at harvest and after storage, and these lower concentrations were associated with less damage to cellular membranes (lipid peroxidation) and proteins (carbonyl group content). Higher activities of the H2O2-degrading enzymes, guaiacol-peroxidases, and catalases, were related to lower H2O2 content and lower scald susceptibility. Activities of superoxide dismutase, a H2O2-generating enzyme, were not related to scald susceptibility or storage period. We hypothesize that fruit susceptibility to scald is strongly influenced by cellular efficiency in metabolizing active oxygen species such as H2O2.

The goal of this research was to develop an efficient transformation system for 'Marshall McIntosh' apple. To determine the optimum combination of agar and Gelrite gelling agents in the media to maximize regeneration and minimize hyperhydicity (vitrification), the following combinations of agar (A)+Gelrite (G) in g l-1 were tested: 7.0 A+0 G; 5.2 A+0.6 G; 3.5 A+2.5 G; 1.7 A+1.8 G; and 0 A+2.5 G. Both 5.2 A+0.6 G and 3.5 A+1.2 G provided greatest regeneration of healthy non-hyperhydric shoots. To determine the optimal concentration of aminoglycoside for the selection and regeneration of transgenic 'Marshall McIntosh' on agar-Gelrite-based media, kanamycin was tested at 0, 10, 25, 50, 75 and 100 mg l-1, and paromomycin was tested at 0, 50, 100, 150, 200 and 250 mg l-1. Kanamycin was more effective than paromomycin in the initial selection of transgenics. For selection of transformants of 'Marshall McIntosh', the use of kanamycin at 25 mg l-1on 5.2 A+0.6 G solidified medium is suggested. By optimizing the medium and selection conditions, a protocol was developed that resulted in four transgenic lines as confirmed by a GUS assay, NPT II ELISA, PCR, and Southern analysis. In repeated experiments with this protocol, transformation efficiencies of 3.1 and 2.6% were obtained.

Seven nptII and gus transgenic lines of the apple (Malus ×domestica Borkh.) rootstock Malling 7 (M.7) were examined by glucuronidase (GUS) histochemical testing and a double-antibody sandwich enzyme-linked immunosorbent assay (ELISA). These lines had different amounts of neomycin phosphotransferase II (NPTII). The amounts of NPTII among lines was positively correlated with the ability of the transgenic lines to regenerate in the presence of kanamycin, paromomycin, or geneticin. Regenerants derived from transgenic lines also varied greatly in GUS expression. The apical portion of regenerant stem tissues had stronger GUS staining than the basal portion of stem. All regenerated tissue of T1, a transgenic line originally classified as a uniform GUS staining line, showed non-GUS staining, while the regenerated tissues of chimeric transgenic lines showed nonstaining, chimeric staining, or uniform GUS staining, indicating the potential to select uniform GUS staining lines from chimeras. Polymerase chain reaction (PCR) indicated the gus gene was present in GUS negative (nonstaining) lines. Negative PCR results with primers derived from vir G of Agrobacterium tumefaciens, and failure to isolate A. tumefaciens from M.7 transgenics indicated that PCR and GUS staining results were not due to A. tumefaciens. A modified PCR methylation assay (MPMA) indicated that methylation of cytosines of the CCGG site in the gus gene, and in the border between the CaMV35S promoter and the gus gene, was positively correlated with complete gus gene silencing (nonstaining lines). However, the MPMA indicated that methylation was not always associated with variable GUS expression, suggesting that chimeric staining could be due to a mixture of transformed and nontransformed cells in some transgenic lines.

Genetic linkage maps were created for three apple (Malus ×domestica Borkh.) cultivars using data from two progenies (`Wijcik McIntosh' xNY 75441-67 and `Wijcik McIntosh' xNY 75441-58). The maps consist primarily of randomly amplified polymorphic DNA (RAPD) markers, but also contain six isozyme loci and four morphological markers (Rf, fruit skin color; Vf, scab resistance; Co, columnar growth habit; Ma, malic acid). Maps were constructed using a double pseudotestcross mapping format and JoinMap mapping software. An integrated `Wijcik McIntosh' map was produced by combining marker data from both progenies into a single linkage map. Homologous linkage groups from paternal maps were paired with their counterparts in the `Wijcik McIntosh' map using locus bridges composed of markers heterozygous in both parents of a progeny. The `Wijcik McIntosh' map consists of 238 markers arranged in 19 linkage groups spanning 1206 cM. The NY 75441-67 map contains 110 markers in 16 linkage groups and the NY 75441-58 map consists of 183 markers in 18 linkage groups. The average distance between markers in the maps was ≈5.0 cM.

A simple genetic basis for the red/yellow skincolor polymorphism in apple was verified using DNA markers. Bulked segregant analysis identified one 10-base oligomer that generated different fragments in each of the bulks. After testing the primer in four populations, two fragments were found to be associated with red skin color and another two fragments associated with yellow skin color. Three of the fragments (1160, 1180, and 1230 bp) were partly sequenced and found to share high sequence homology, suggesting these were generated from the same locus. A pair of universal primers were designed to amplify the fragments. In the 'Rome Beauty' x 'White Angel' population, two fragments were associated with red skin color; one fragment designated as A(1) (1160 bp) was from 'Rome Beauty' and another fragment (A(2), 1180 bp) was from 'White Angel'. Progeny possessing both fragments, or either one, had red fruit. Both parents displayed an alternate fragment, a(1) (1230 bp), associated with yellowskinned fruit. In three other crosses tested, only fragment A(1) co-segregated with red skin color; two fragments, a(1) and a(2) (1230 bp and 1320 bp), were associated with yellow skin color. Our results are consistent with the hypothesis that the red/yellow dimorphism is controlled by a monogenic system with the presence of the red anthocyanin pigmentation being dominant. There was no indication that other modifier genes could reverse the effect of the locus (R f ) linked to the markers. Examination of amplification products in 56 apple cultivars and advanced breeding selections demonstrated that the universal primers could be used to correctly predict fruit skin color in most cases.

A barrier system for pest control consisting of insect-exclusionary cages covered with three types of mesh material was placed over columnar apple (Malus domestica Borkh.) trees. This system has been shown to provide arthropod control equivalent to insecticides. Light intensity, evaporation, and air and soil temperature were reduced inside the cages. Shoot elongation of columnar apple trees grown inside insect-exclusionary cages was significantly greater than that of trees grown outside the cages. However, this increased shoot growth was not due to etiolation. Tree performance was unaffected by insect-exclusionary cages. Fruit set and fruit soluble solids concentration were not reduced by the cages; however, fruit color intensity was reduced as the degree of shading from the mesh increased. These findings, in conjunction with high levels of arthropod control by insect-exclusionary cages, may allow insect-exclusionary cages to be used for evaluating integrated pest management thresholds, predator-prey relationships, and apple production without insecticides.

Two types of exclusionary cages covered with three types of mesh material were placed over columnar apple trees to determine whether direct fruit-damaging insect pests could be prevented from attacking fruit on these trees. Exclusionary cages covered with fine (pore size 1.0 mm × 0.13 mm) and medium (pore size 1.0 mm × 1.5 mm) mesh materials provided good control of direct fruit feeding and phytophagous arthropods without the use of insecticides. Biological control of aphids and mites was obtained on trees beneath exclusionary cages. Exclusionary cages in conjunction with columnar apple trees may provide an insecticide-free orchard environment suitable for detailed evaluations of integrated pest management thresholds and predator-prey relationships. They may also be suitable for low-chemical input apple-production systems.

Physical and biological parameters affecting the efficiency of biolistic transformation of peach were optimized using ß-glucuronidase (GUS) as a reporter gene, such that efficiency of transient GUS expression in peach embryo-derived callus was increased markedly. Transient expression was also obtained in embryonic axes, immature embryos, cotyledons, shoot tips, and leaves of peach. Stable expression of a fusion gene combining neomycin phosphotransferase (NPTII) and ß-glucuronidase activities has been achieved in peach embryo calli. Sixty-five kanamycin-resistant callus lines were obtained from 114 pieces of bombarded calli after 4 months of selection. Nineteen of the 65 putative transformant lines produced shoot-like structures. Seven lines were examined to confirm stable transformation using the colorimetric GUS assay and PCR analysis. All seven lines showed GUS activity. PCR analysis confirmed that, in most of the putative transformants, the chimeric GUS/NPTII gene had been incorporated into the peach genome. The transgenic callus lines were very weakly morphogenic, presumably because the callus was 5 years old and no transgenic shoots developed from this callus. Results of this research demonstrate the feasibility of obtaining stable transgenic peach tissue by biolistic transformation.

A crab apple clone (Malus brevipes 1021), highly resistant to the apple maggot, is being used in breeding programs developing commercial apple cultivars. This study has discovered that this crab apple contains a natural cholinesterase (ChE) inhibitor that caused a 17.5% in vitro inhibition of rat blood ChE activity. This crab apple also showed a relatively high total (titratable) acidity of 1.28%. The commercial, nonresistant, apple cultivar McIntosh was capable of causing a 7.9% inhibition of blood ChE in vitro. The total acidity in McIntosh was 0.45%. A 4-wk feeding study compared 2 groups of 5-wk-old Fischer 344 male rats fed diets containing 45% of either M. brevipes or McIntosh freeze-dried apples to a third (control) group of rats fed a semipurified diet. In vivo blood ChE activities were similar in all groups of rats, as well as hemoglobin, hematocrit, and red blood cell counts. The liver mixed-function oxidase activity through aminopyrine N-demethylase in the rats fed the apple diets was higher than the controls, but p-nitroanisole O-demethylase activity was induced only in the animals fed the maggot-resistant crab apple. Lowered growth with concomitant lowered food intake, in the otherwise healthy rats fed the maggot-resistant crab apple diet, was attributed to the less palatable, highly acidic fruit. This study indicates that the natural ChE inhibitor in the insect-resistant apple M. brevipes is apparently detoxified upon ingestion.

This research compares several national-origin groups in terms of how parents’ entry, legalization and naturalization (i.e., membership) statuses relate to their children's educational attainment. In the case of Asian groups, the members of which predominantly come to the United States as permanent legal migrants, we hypothesize (1) that father's and mother's statuses will be relatively homogenous and few in number and (2) that these will exert minimal net effects on second-generation attainment. For Mexicans, many of whom initially come as temporary unauthorized migrants, we hypothesize (1) that parental status combinations will be heterogeneous and greater in number and (2) that marginal membership statuses will exert negative net effects on education in the second generation. To assess these ideas, we analyze unique intergenerational data from Los Angeles on the young adult members of second-generation national-origin groups and their parents. The findings show that Asian immigrant groups almost universally exhibit similar father–mother migration statuses and high educational attainment among children. By contrast, Mexicans manifest more numerous discrepant father–mother combinations, with those in which the mother remains unauthorized carrying negative implications for children's schooling. The paper discusses the theoretical and policy implications of the delays in incorporation that result from Mexican Americans needing extra time and resources compared to the members of other groups to overcome their handicap of marginal membership status {i.e., being more likely to enter and remain unauthorized).

Over the past four decades, Mexican immigration has garnered much of the public and legislative attention devoted to reforming immigration policy in the United States (Bean and Lowell 2004). Part of the reason is that Mexicans have constituted the largest of the country’s recent legal immigrant groups. In 2005, for example, 161,445 Mexicans gained legal permanent residency, or 14.4 percent of the all such persons (Office of Immigration Statistics 2006). But much of the focus falls on Mexicans because they comprise such an overwhelming component of unauthorized migration flows. Roughly 300,000 (net) unauthorized Mexicans established de facto U.S. residency in 2005, bringing the total number of unauthorized Mexicans to 6.2 million, or 56 percent of all unauthorized persons in the country (Passel 2006). These numbers dwarf those from any other nation. Moreover, many observers have long argued that policies to curtail or “regularize” unauthorized migration should be adopted before changes in legal immigration policy are considered, thus ensuring that unauthorized Mexican migration occupies a prominent place in any debate over immigration policy (U.S. Commission on Immigration Reform 1994).

Introduction As Joseph S. Nye (2002: 9) has so cogently noted, a country’s “soft” power (or its capacity “to get others to want what it wants” through means other than military force) depends on its culture, especially its educational system and the strength of its science and technology sectors. Science and technology are particularly important because economic growth in knowledge-based societies arguably hinges on technological innovation (Freeman 2005). While the mechanisms by which technology spurs growth are debated (Barro and Sala-i-Martin 2003; Lindert 2004), inventions such as wrought iron, steam power, the generation of electricity, and the internal combustion engine have historically generated major economic expansions (Easterlin 1996; Galbraith 1995, 1997). The invention of the computer and the Internet may ultimately contribute as much as these others to the economy, although not every analyst agrees on this point (Madrick 2002). Regardless, national science and technology policies generally seek to protect and sustain high-technology innovation to foster international economic competitiveness. Such relative economic strength reflects aspects of culture that contribute to the development and maintenance of soft power.

19 pages, 3 figures, 2 tables.-- PMID: 18487361 [PubMed].-- PMCID: PMC2442536.-- Printed version published Jul 2008., The plant family Rosaceae consists of over 100 genera and 3,000 species that include many important fruit, nut, ornamental, and wood crops. Members of this family provide high-value nutritional foods and contribute desirable aesthetic and industrial products. Most rosaceous crops have been enhanced by human intervention through sexual hybridization, asexual propagation, and genetic improvement since ancient times, 4,000 to 5,000 B.C. Modern breeding programs have contributed to the selection and release of numerous cultivars having significant economic impact on the U.S. and world markets. In recent years, the Rosaceae community, both in the United States and internationally, has benefited from newfound organization and collaboration that have hastened progress in developing genetic and genomic resources for representative crops such as apple (Malus spp.), peach (Prunus spp.), and strawberry (Fragaria spp.). These resources, including expressed sequence tags, bacterial artificial chromosome libraries, physical and genetic maps, and molecular markers, combined with genetic transformation protocols and bioinformatics tools, have rendered various rosaceous crops highly amenable to comparative and functional genomics studies. This report serves as a synopsis of the resources and initiatives of the Rosaceae community, recent developments in Rosaceae genomics, and plans to apply newly accumulated knowledge and resources toward breeding and crop improvement.

Oviposition and larval survival of Rhagoletis pomonella (Walsh) varied significantly among fruit from 25 crab apple speciesand clones evaluated in field and laboratory studies. In general, the relative oviposition preference and larval survival was similar in fruit infested naturally in the field and fruit tested in the laboratory. Flies oviposited more in clones with larger fruit, although this relationship was more pronounced in laboratory tests when fruit was infested by laboratory-reared flies than in fruit infested in the field by wild flies. ‘Aldenhamensis,’ ‘Fuji,’ ‘Vilmorin,’ Malus zumi calocarpa Rehd., and M. hupehensis (Pamp) Rehd. fruit was not infested in the field, but flies oviposited in fruit of all 25 species and clones in choice tests in the laboratory. Eggs hatched but larvae did not survive in fruit of ‘Henry F. DuPont,’ ‘Frettingham,’ ‘Fuji,’ ‘Sparkler,’ M. hupehensis , and M. zumi calocarpa . Larval mortality was very high in fruit from ‘Vilmorin,’ ‘Sparkler,’ ‘NA 40298,’ ‘Henrietta Crosby,’ ‘Golden Gem,’ ‘Almey,’ M. baccata L. (Borkh.), and M. sikktmensis (Hook.) Koehne.

SummaryHemophilia A is caused by factor VIII deficiency that historically has been treated with either a cryoprecipitate fraction of serum or factor VIII concentrate. Recently, the availability of affinity isolated factor VIII (Monoclate®) has allowed for a highly purified preparation for the chronic therapy of hemophilia A. This factor VIII preparation contains a trace quantity (

As the United States begins the twenty-first century, it remains the world's leading immigration country. In 2000 (the latest year for which migration data are available on a global basis) the United States was home to almost 35 million legal and unauthorized migrants, or 2.7 times as many as any other country. Although other nations have higher proportions of foreign-born residents (e.g., nearly 25 percent in Australia and 20 percent in Canada), the globally dominant position of the United States in regard to numbers of new immigrants reinforces its self-image as a “nation of immigrants,” as does the fact that immigration is generally seen as contributing to the country's economic and demographic strength. However, over the past three decades, more and more new arrivals with non-European origins have come to the country (more than four-fifths are Latino and Asian), many with very low levels of education and illegal status at entry. These changes have fueled public concerns and led to heated debates over whether U.S. admissions and settlement-related policies ought to be modified.Frank D. Bean is Professor of Sociology (fbean@uci.edu), Susan K. Brown is Assistant Professor of Sociology (skbrown@uci.edu),and Ruben G. Rumbaut is Professor of Sociology at University of California, Irvine (rrumbaut@uci.edu). Some of the research results reported in this paper come from a research project entitled “Immigration and Intergenerational Mobility in Metropolitan Los Angeles” and supported by a grant from the Russell Sage Foundation.

This chapter uses census data to study the massive suburbanization or outward spread of population in U.S. metropolitan areas during the twentieth century and initial stages of the twenty-first century. In decade by decade comparisons of the post-World War II period, we find that the size of the suburban population has increased in a rapid continuous pattern. Central cities have shown varied patterns of growth over decades, but no evidence exists that they are typically experiencing major growth in population numbers. Within the suburban rings of metropolitan areas, the major factors affecting their recent growth are previous population density (low = high overall growth) and the in-movement of the foreign born (high in-movement = high overall growth). We also provide some analysis of the suburbanization of the United States since its founding and the growth of suburban areas around metropolitan areas in the less developed world. Recent decades have been characterized in many countries around the world by very high metropolitan population growth, including in their suburban rings.

Pgm-1, the gene responsible for variation in the most anodal isozyme of phosphoglucomutase in apple ( Malus spp.), is shown to lie ≈8 centiMorgans from the gene V f , which confers apple-scab resistance. The proximity of the marker and the ease by which allozymic forms can be resolved suggest that Pgm-1 will be useful for following the inheritance of scab resistance conferred by V f . 2 Dept. of Plant Pathology. Apple scab, caused by Venturia inaequalis (Cke.) Wint., is one of the most serious diseases of apple. In areas with favorable environmental conditions for disease development, no fewer than eight to ten fungicide sprays per year are applied to avoid losses in apple orchards. Surveys of Malus germplasm have identified several clones with a high level of apple-scab resistance. When assayed under greenhouse conditions, distinct reaction classes can be identified: no visible sign of infection (class 0), pinpoint pits with no sporulation (class 1), irregular chlorotic or necrotic spots with no sporulation (class 2), few restricted sporulating lesions (class 3), a mixture of class 2 and class 3 lesions (class M), or extensive and abundantly sporulating lesions (class 4) (Shay and Hough, 1952; Williams and Kuc, 1969). Although several sources of apple-scab resistance have been identified, most breeding programs have relied on the V f gene derived from M. floribunda 821. The resistant reaction in later generations of M. floribunda 821 backcrosses with susceptible commercial cultivars is usually a chlorotic lesion with a variable level of sporulation, probably depending on the presence of minor genes contributing to resistance (Rousselle et al., 1974). The resistance reaction is conditioned by the dominant V f gene (Hough, 1944; Williams et al., 1966) and may be expressed as a class 1, 2

Apple fruit cultivars and rootstocks are propagated vegetatively, and are characterized by extreme genotype preference by nurseries, growers, and consumers. Furthermore, apple is generally heterozygous, shows severe inbreeding depression, and has an excessive generation time. Thus genetic engineering, a priori, is preferred to sexual breeding for improving established fruit cultivars and rootstocks. Efficient Agrobacterium tumefaciens-mediated transformation using binary vectors and kanamycin resistance selection has now been well established. Prime targets for genetic engineering are disease and insect resistance, which would address the perceived environmental and public health concerns of substantial use of chemical pesticides in apple production. Promising results have been obtained in terms of increasing the resistance to the most important fungal (apple scab) and bacterial (fire blight) diseases of apple worldwide, using transgenes for chitinolytic enzymes and for lytic proteins, respectively. Thus far, positive results have been obtained with single transgenes. Based on in vitro synergism against the pathogens, it is likely that plants containing two chitinolytic or lytic protein transgenes will have greatly enhanced resistance to fungi and bacteria, respectively. Such transgenic plants have now been obtained and are being evaluated for disease resistance.

The overall goal of this research is to develop scab resistance in apples by transforming them with genes coding for chitinolytic enzymes from the biocontrol fungus Trichoderma harzianum. Agrobacterium- mediated transformation was used to transfer an endochitinase (ThEn-42) gene into Marshall Mcintosh (MMc) apples. Varying levels of expression of ThEn-42 were found in different lines. Transgenic MMc lines expressing ThEn-42 were more resistant to apple scab than the parental lines as indicated with both grafted and own-rooted plants. There was a negative correlation between level of ThEn-42 expression and plant vigor. However, plants with intermediate levels of expression were substantially less susceptible than nontransgenics and some plants with intermediate levels of resistance had good vigor. Recently, we cloned an exochitinase gene encoding N-acetyl-s-D-glucosaminidase (ThNag-70) from T. harzianum, and obtained ThNag-70 transgenic-MMc lines. A very high efficiency of transformation was obtained using the Agrobacterium strain EHA105-PCH32. Previous reports have demonstrated a strong in vitro synergistic activity between ThEn-42 and ThNag-70 against fungal pathogens. Both ThEn-42 and ThNag-70 were cloned into a single construct, and transgenic lines expressing both these enzymes were obtained. Presently the ThNag-70 transgenic lines and the lines expressing both ThEn-42 and ThNag-70 are being tested for scab resistance. We hypothesize that plants with “pyramided” genes, that express more than one synergistic protein, will be resistant to diseases even at relatively low levels of enzyme production and also have good vigor.

Genes encoding lytic proteins, attacin E (att E) and T4 lysozyme (T4 L), were cloned into 6 different plasmid binary vectors for use in Agrobacterium-mediated transformation of apple. All 6 constructs containing att E, T4 L, or both were successfully transferred to Galaxy by Agrobacterium-mediated transformation. Apple transgenics have been recovered with all six constructs. NPTII ELISA and transgene PCR have confirmed transgene transformation with att E and T4 L. Transformation rate varied among different plasmid constructs. The transformation rate of pCa2AMVAtt plasmid vector was lower than with other plasmids. All att E transgenic lines expressed att E. However, the protein expression level was different among transgenic lines. pCa2AMVSPAtt transgenic lines had low expression of att E compared to other att E transgenic lines. In pCa2AMVSPAtt transgenic lines, att E was detected in total apple protein but not in intercellular fluid. Inoculation of transgenic lines indicated that some lines have increased resistance to fire blight. Fusion att E was produced using the pRSET E. coli expression vector and purified. The purified fusion att E and T4 L were used successfully to obtain polyclonal antibodies for protein analysis.

Etude de la composition en phenol et de l'activite PPO dans differents cultivars et correlation avec le brunissement observe au cours de la maturation et de la recolte. L'etude a pour but de selectionner les cultivars presentant le minimum d'alteration en cours de manipulation et de transformation

Extensive linkage maps, consisting primarily of molecular markers, are being developed for apple, pear, and grape varieties. The intrinsically high heterozygosity of outcrossing perennial species is utilized to produce segregating populations directly from a cross between varieties. Nearly complete linkage maps have been generated for the apple varieties ‘Rome Beauty’ and ‘White Angel’. The map for ‘Rome Beauty’ contains 161 molecular markers, while that for ‘White Angel’ has 251 markers. Maps for the pear varieties, ‘Bartlett’ and NY10353, also are being developed. Linkages conserved between the pear and apple genomes have been identified. In grapes, maps for four varieties are available, the most extensive being those for ‘Cayuga White’ and ‘Aurore’. The apple maps have been used to investigate the genetic basis of morphological and physiological characters. A gene controlling the presence of anthocyanins in the skin of the fruit is located on linkage group 3. Genes controlling early bud break, branching habit, and production of root suckers have also been identified and mapped.

People magazine featured apple breeders Bob Lamb and Roger Way in an article and said that, for them, “pomology is a magnifi cent obsession.” Bob has also been featured in newspaper articles “Apple Polisher” and “In Pursuit of the Perfect Apple.” Bob Lamb was born in Saskatoon, Saskatchewan, Canada(1919–1997). He obtained his MS and PhD degrees at the University of Minnesota. He started at Cornell University’s New York State Agricultural Experiment Station in Geneva in 1949 as an assistant professor. He chose research projects that were very challenging, including resistance to pear psylla, the early introgression of apple scab resistance genes, breeding apples with multiple resistances (scab, mildew, cedar apple rust, and fi re blight), cold hardiness of stone fruit, and the inheritance of bitter versus sweet kernels in apricots. As new techniques became available, Bob was eager to collaborate, as exemplifi ed by his research with Norman Weeden on genetics and linkage analysis in apple using isozymes. Bob’s resistance research, in collaboration with Herb Aldwinckle, added greatly to our knowledge of resistance mechanisms and provided valuable germplasm for future breeding Bob was responsible for the development and naming of the following cultivars: the scab-resistant ‘Liberty’ (1978) and ‘Freedom’ (1983) apples, ‘New Yorker’ (1967) nectarine, ‘Brighton’ (1972) and ‘Eden’ (1972) peaches, and ‘Aurora’ (1964) and ‘Highland’ (1974) pears. Bob was active in the American Pomological Society (serving as its president for two terms), the Apple and Pear Breeders’ Cooperatives, and the American Society for Horticultural Science. He was awarded the Wilder medal from the American Pomological Society in recognition of his research in fruit breeding. He was active in the New York Fruit Testing Association, and his activities were instrumental in the development of the U.S. Department of Agriculture’s National Clonal Repository for Apples and Grapes at Geneva. Bob typifi ed the hard-working, dedicated scientist who continued to come in every day even after he had to bring along a tank of supplemental oxygen. Once, a group of us had planned a canoe trip over a long weekend and Bob expressed concern because “we don’t get Columbus day off.” A colleague said, “Bob, you are retired—you get every day off! New York Tree Fruit Breeders

The S alleles of 15 Japanese apple cultivars were determined by using the allele-specific polymerase chain reaction amplification and restriction enzyme digestion system developed by Janssens et al. (1995). Both S alleles were identified in eight diploid cultivars, two S alleles in three triploid cultivars, and one S allele in the remaining four diploid cultivars. Two cultivars had S alleles different than those predicted by their parentage, and in one comparison of a cultivar with its sport, an identity problem was discovered. The technique helped to indicate the parent contributing the unreduced gamete in triploids.

Apple scab, Venturia inaequalis (Cke.) Wint., is one of the most damaging diseases of apples. Although fungicide sprays have been used to control the disease, genetic resistance in existing commercially important varieties would be desirable. Identification of molecular marker(s) would be helpful in devising biotechnological approaches to control the disease. We used bulk segregant analysis to identify RAPD markers that cosegregate or display a tight linkage with Vf gene in Prima × Spartan cross. Using this approach, we are saturating the region around the scab resistance gene for the purpose of bracketing the locus. We have identified several markers associated with the Vf locus. The closest markers have been isolated and sequenced to be used as SCARs. The relationship and distances of the markers with the Vf locus and other previously reported markers will be discussed.