Search

Societal Impact Statement: The English West Country is the home of cider making, providing the region with jobs and industry, as well as cultural reference points such as Laurie Lee's Cider with Rosie. Many important cider apple varieties were developed at Long Ashton Research Station (LARS), near Bristol, UK, including 29 varieties known collectively as 'The Girls'. After its closure, some of the knowledge and expertise acquired at Long Ashton was lost, including the pedigree of 'The Girls'. We sampled LARS' derived trees and, using a novel genotyping technique, rediscovered the pedigree of 'The Girls', ensuring that this important cider apple collection will be available for future generations. SummaryOur research had two objectives: (a) record the influence of Long Ashton Research Station on the introduction of new cider apple cultivars to the UK; (b) rediscover the parentage of the cider apple cultivars known collectively as 'The Girls'.For rapid, cost effective and accurate genotyping, we used the recently developed, medium density, single nucleotide polymorphism‐based genotyping procedure, SEQSNP®, to characterize the cultivars.We generated a medium density (1,500 markers), whole genome genotype for 245 apple cultivars that allowed us to determine the relationship between cultivars and, in so doing, rediscover the parentage of 'The Girls'.We show that SNP genotyping is an efficient tool for the analysis of genetic diversity in cider apples and apples in general, and that the cider apple breeding programme carried out at Long Ashton Research Station made, and continues to make, a unique contribution to UK cider production. [ABSTRACT FROM AUTHOR]

Summary: Cytosine methylation is an essential feature of epigenetic regulation and is involved in various biological processes. Although cytosine methylation has been analysed at the genomic scale for several plant species, there is a general lack of understanding of the dynamics of global and genic DNA methylation in plants growing in environments challenged with biotic and abiotic stresses. In this study, we mapped cytosine methylation at single‐base resolution in the genome of commercial apple (Malus x domestica), and analysed changes in methylation patterns associated with water deficit in representative drought‐sensitive and drought‐tolerant cultivars. We found that the apple genome exhibits ~54%, ~38% and ~8.5% methylation at CG, CHG and CHH sequence contexts, respectively. We additionally documented changes in gene expression associated with water deficit in an attempt to link methylation and gene expression changes. Global methylation and transcription analysis revealed that promoter‐unmethylated genes showed higher expression levels than promoter‐methylated genes. Gene body methylation appears to be positively correlated with gene expression. Water deficit stress was associated with changes in methylation at a multitude of genes, including those encoding transcription factors (TFs) and transposable elements (TEs). These results present a methylome map of the apple genome and reveal widespread DNA methylation alterations in response to water deficit stress. These data will be helpful for understanding potential linkages between DNA methylation and gene expression in plants growing in natural environments and challenged with abiotic and biotic stresses. [ABSTRACT FROM AUTHOR]

The nature and structure of genetic diversity in the Spanish apple germplasm preserved at the national level was widely unknown, since studies performed to date on this topic have been exclusively carried out at the regional scale. Here, 1453 accessions from Spanish collections of Malus × domestica were evaluated with a common set of 13 SSR (Simple Sequence Repeats) markers in order to estimate genetic diversity, to identify the underlying genetic structure and to unravel the relationships among them and among a wide set of international cultivars for reference. In total, 737 unique genotypes were identified, 581 diploids and 156 triploids. Using a model-based Bayesian clustering procedure, two reconstructed populations were obtained for diploid genotypes; one retaining only Spanish cultivars (42% of genotypes), and a second containing all foreign cultivars the latter exhibiting evidence supporting the existence of a secondary sub-structure. Similarly, analysis performed on the 156 triploid genotypes also revealed two reconstructed populations; one exclusively associated with local Spanish genotypes (44%). The Jaccard coefficient allowed clustering by UPGMA (Unweighted Pair Group Method) diploid and triploid genotypes, and remarkable differences in allelic composition among the different partitioning levels were found. AMOVA analyses showed moderate but significant differentiation among the main groups (0.08 ≤ F ST ≤ 0.12). Our results highlight an important fraction of the Spanish apple germplasm that constitutes a differentiated genepool with respect to the international and commercial apple cultivars. Moreover, the extent of the Spanish genetic diversity was spatially distributed along the northern Iberian Peninsula, suggesting an extensive migration of genotypes along the country. This study is the first valuable action for genetic conservation of apple at the national scale, and constitutes a decisive step towards the definition of a Spanish core collection that will be useful for further studies in dissecting the genetic control of important horticultural traits through genome-wide association analysis in apple. [ABSTRACT FROM AUTHOR]

Identifying DNA sequence variations is a fundamental step towards deciphering the genetic basis of traits of interest. Here, a total of 20 cultivated and 10 wild apples were genotyped using specific-locus amplified fragment sequencing, and 39,635 single nucleotide polymorphisms with no missing genotypes and evenly distributed along the genome were selected to investigate patterns of genome-wide genetic variations between cultivated and wild apples. Overall, wild apples displayed higher levels of genetic diversity than cultivated apples. Linkage disequilibrium (LD) decays were observed quite rapidly in cultivated and wild apples, with an r2-value below 0.2 at 440 and 280 bp, respectively. Moreover, bidirectional gene flow and different distribution patterns of LD blocks were detected between domesticated and wild apples. Most LD blocks unique to cultivated apples were located within QTL regions controlling fruit quality, thus suggesting that fruit quality had probably undergone selection during apple domestication. The genome of the earliest cultivated apple in China, Nai, was highly similar to that of Malus sieversii, and contained a small portion of genetic material from other wild apple species. This suggested that introgression could have been an important driving force during initial domestication of apple. These findings will facilitate future breeding and genetic dissection of complex traits in apple. [ABSTRACT FROM AUTHOR]

Dehydration-responsive element binding factors (DREBs) play important roles in plant growth, development, and stress signaling pathways in model plants. However, little is known about the function of DREBs in apple (Malus 3 domestica), a widely cultivated crop that is frequently threatened by drought. We isolated a DREB gene from Malus sieversii (Ledeb.) Roem., MsDREB6.2, and investigated its functions using overexpression analysis and chimeric repressor gene-silencing technology (CRES-T). We identified possible target genes of the protein encoded by MsDREB6.2 using electrophoretic mobility shift assays (EMSAs) and chromatin immunoprecipitation (ChIP). Overexpression of MsDREB6.2 increased the expression of a key cytokinin (CK) catabolism gene, MdCKX4a, which led to a significant reduction in endogenous CK levels, and caused a decrease in shoot:root ratio in transgenic apple plants. Overexpression of MsDREB6.2 resulted in a decrease in stomatal aperture and density and an increase in root hydraulic conductance (L0), and thereby enhanced drought tolerance in transgenic plants. Furthermore, manipulating the level of MsDREB6.2 expression altered the expression of two aquaporin (AQP) genes. The effect of the two AQP genes on L0 was further characterized using the AQP inhibitor HgCl2. Based on these observations, we conclude that MsDREB6.2 enhances drought tolerance and that its function may be due, at least in part, to its influence on stomatal opening, root growth, and AQP expression. These results may have applications in apple rootstock breeding programs aimed at developing drought-resistant apple varieties. [ABSTRACT FROM AUTHOR]

Ripening in climacteric fruit requires the gaseous phytohormone ethylene. Although ethylene signaling has been well studied, knowledge of the transcriptional regulation of ethylene biosynthesis is still limited. Here we show that an apple ( Malus domestica) ethylene response factor, Md ERF2, negatively affects ethylene biosynthesis and fruit ripening by suppressing the transcription of Md ACS1, a gene that is critical for biosynthesis of ripening-related ethylene. Expression of Md ERF2 was suppressed by ethylene during ripening of apple fruit, and we observed that Md ERF2 bound to the promoter of Md ACS1 and directly suppressed its transcription. Moreover, Md ERF2 suppressed the activity of the promoter of Md ERF3, a transcription factor that we found to bind to the Md ACS1 promoter, thereby increasing Md ACS1 transcription. We determined that the Md ERF2 and Md ERF3 proteins directly interact, and this interaction suppresses the binding of Md ERF3 to the Md ACS1 promoter. Moreover, apple fruit with transiently downregulated Md ERF2 expression showed higher ethylene production and faster ripening. Our results indicate that Md ERF2 negatively affects ethylene biosynthesis and fruit ripening in apple by suppressing the transcription of Md ACS1 via multiple mechanisms, thereby acting as an antagonist of positive ripening regulators. Our findings offer a deep understanding of the transcriptional regulation of ethylene biosynthesis during climacteric fruit ripening. [ABSTRACT FROM AUTHOR]

In this study, we characterized the role of an apple cytosolic malate dehydrogenase gene ( Mdcy MDH) in the tolerance to salt and cold stresses and investigated its regulation mechanism in stress tolerance. The Mdcy MDH transcript was induced by mild cold and salt treatments, and Mdcy MDH-overexpressing apple plants possessed improved cold and salt tolerance compared to wild-type ( WT) plants. A digital gene expression tag profiling analysis revealed that Mdcy MDH overexpression largely altered some biological processes, including hormone signal transduction, photosynthesis, citrate cycle and oxidation-reduction. Further experiments verified that Mdcy MDH overexpression modified the mitochondrial and chloroplast metabolisms and elevated the level of reducing power, primarily caused by increased ascorbate and glutathione, as well as the increased ratios of ascorbate/dehydroascorbate and glutathione/glutathione disulphide, under normal and especially stress conditions. Concurrently, the transgenic plants produced a high H2O2 content, but a low [ABSTRACT FROM AUTHOR]

Flower induction in apple ( Malus domestica Borkh.) trees plays an important life cycle role, but young trees produce fewer and inferior quality flower buds. Therefore, shoot bending has become an important cultural practice, significantly promoting the capacity to develop more flower buds during the growing seasons. Additionally, micro RNAs (mi RNAs) play essential roles in plant growth, flower induction and stress responses. In this study, we identified mi RNAs potentially involved in the regulation of bud growth, and flower induction and development, as well as in the response to shoot bending. Of the 195 mi RNAs identified, 137 were novel mi RNAs. The mi RNA expression profiles revealed that the expression levels of 68 and 27 known mi RNAs were down-regulated and up-regulated, respectively, in response to shoot bending, and that the 31 differentially expressed novel mi RNAs between them formed five major clusters. Additionally, a complex regulatory network associated with auxin, cytokinin, abscisic acid ( ABA) and gibberellic acid ( GA) plays important roles in cell division, bud growth and flower induction, in which related mi RNAs and targets mediated regulation. Among them, mi R396, 160, 393, and their targets associated with AUX, miR159, 319, 164, and their targets associated with ABA and GA, and flowering-related mi RNAs and genes, regulate bud growth and flower bud formation in response to shoot bending. Meanwhile, the flowering genes had significantly higher expression levels during shoot bending, suggesting that they are involved in this regulatory process. This study provides a framework for the future analysis of mi RNAs associated with multiple hormones and their roles in the regulation of bud growth, and flower induction and formation in response to shoot bending in apple trees. [ABSTRACT FROM AUTHOR]

Molecular marker analysis can be an effective tool when searching for new fire blight resistance donors. It can speed up the breeding process as well, even though many of the available markers linked to fire blight resistance QTLs have not yet been tested by screening a large number of cultivars. The aim of this study was to search for alternate sources of the three major QTLs of fire blight resistance; FBF7, FB_ MR5 and FB_E, as well as to test the efficiency of some markers linked to minor QTLs. Altogether, nine primer pairs were used on 77 genotypes including new Hungarian cultivars and old apple cultivars from the Carpathian basin. Several marker alleles of FB resistance QTLs have been detected in the screened genotypes, most importantly the alleles coupling with FB_ MR5 in the old cultivars 'Kéresi muskotály', 'Szabadkai szercsika' and 'Batul'. We propose these cultivars as the first available resistance donors of FB_ MR5 instead of the crabapple Malus × robusta 5. The results also bring new information regarding the resistance alleles of new Hungarian cultivars and selections. [ABSTRACT FROM AUTHOR]

In apple, two MYB transcription factors Md MYB10 ( R 6 : Md MYB10) and Md MYB110a have been shown to be responsible for the type 1 and type 2 red flesh traits, respectively. While type 1 red-fleshed apples are characterized by a red coloration not only in fruit flesh but also in vegetative tissues such as leaves and flowers, red pigmentation in type 2 red-fleshed apples is limited at the fruit flesh. We have searched cultivars containing both functional MdMYB10 and MdMYB110a and then tried to breed new cultivars containing both functional genes by cross-pollination of ' Geneva' (type 1) and ' Pink Pearl' (type 2). The cultivar having both genes should exhibit superior characteristics, such as a stable red flesh trait throughout fruit maturity, as type 1 reduces its colouring until maturity, whereas type 2 increases until maturity. We could not identify red-fleshed cultivars having both genes; moreover, only one plant of 80 F1 progeny having both genes died in its juvenile stage. From the results, it was suggested that some sort of breeding depression must have occurred. We analysed the expression patterns of the genes within two F1 plants having either MdMYB10 or MdMYB110a gene and found that the expression pattern of MdMYB110a was different from that observed in ' JPP35' (' Jonathan' × ' Pink Pearl'). The MdMYB110a gene in the No. 2804 F1 plant derived from ' Pink Pearl' × ' Geneva' was expressed in the flesh from the beginning of the red coloration through maturity, and seemed to cause upregulation, not only the latter half, but also the first half of the gene in the anthocyanin pathway. [ABSTRACT FROM AUTHOR]

Understanding which factors drive the diversity and community composition of arbuscular mycorrhizal fungi (AMF) is important due to the role of these soil micro-organisms in ecosystem functioning and current environmental threats to AMF biodiversity. Additionally, in agro-ecosystems, this knowledge may help to evaluate their use in making agriculture more sustainable. Here, we used 454-pyrosequencing of small subunit rRNA gene amplicons to quantify AMF diversity and community composition in the roots of cultivated apple trees across 24 orchards in central Belgium. We aimed at identifying the factors (soil chemical variables, organic vs. conventional farming, and geographical location) that affect AMF diversity and community composition. In total, 110 AMF OTUs were detected, of which the majority belonged to the Glomeraceae (73%) and the Claroideoglomeraceae (19%). We show that soil characteristics and farming system, rather than the geographical location of the orchards, shape AMF communities on apple trees. Particularly, plant-available P content of the soil was associated with lower AMF diversity. In orchards with a lower plant-available P content of the soil (P < 100 mg/kg soil), we also found a significantly higher AMF diversity in organically managed orchards as compared to conventionally managed orchards. Finally, the degree of nestedness of the AMF communities was related to plant-available P and N content of the soil, pointing at a progressive loss of AMF taxa with increasing fertilization. Overall, we conclude that a combination of organic orchard management and moderate fertilization may preserve diverse AMF communities on apple trees and that AMF in the roots of apple trees appear not to be dispersal limited at the scale of central Belgium. [ABSTRACT FROM AUTHOR]

The apple is one of the most important fruit species in the world. Turkey has a diverse and ancient apple germplasm that have played a major role in the domestication of the Malus genus. However, so far locally grown Anatolian apple germplasm has largely been uncharacterized. In this study, 171 local apple (M. domestica Borkh.) accessions originated from eco-geographically diverse regions of Anatolia were studied using 16 SSR (simple sequence repeat) loci, which generated 254 alleles. Of the SSR markers used, the CH04g10 locus showed the highest allele diversity. Relatively high genetic similarities were found between some accessions. The factorial correspondence analysis did not clearly separate different all apple accession groups, suggesting that Anatolian apple accessions are highly intermixed. However, most apple accessions were grouped according to their collection sites in structure analyses. In addition, reflecting the richness of the Anatolian apple germplasm, low numbers of synonymous, and identical accessions were identified among the germplasm. Finally, using the publically available SSR data generated in other studies, we investigated genetic relationships between Anatolian accession groups and European apple accession groups. Our results reported here provide a useful base for future studies aimed at investigating the genetic diversity of wild and cultivated apples from Anatolia and the surrounding regions. [ABSTRACT FROM AUTHOR]

Using resistance genes from a crossable donor to obtain cultivars resistant to diseases and the use of such cultivars in production appears an economically and environmentally advantageous approach. In apple, introgression of resistance genes by classical breeding results in new cultivars, while introducing cisgenes by biotechnological methods maintains the original cultivar characteristics. Recently, plants of the popular apple 'Gala' were genetically modified by inserting the apple scab resistance gene Rvi6 (formerly HcrVf2) under control of its own regulatory sequences. This gene is derived from the scab-resistant apple 'Florina' (originally from the wild apple accession Malus floribunda 821). The vector used for genetic modification allowed a postselection marker gene elimination to achieve cisgenesis. In this work, three cisgenic lines were analysed to assess copy number, integration site, expression level and resistance to apple scab. For two of these lines, a single insertion was observed and, despite a very low expression of 0.07- and 0.002-fold compared with the natural expression of 'Florina', this was sufficient to induce plant reaction and reduce fungal growth by 80% compared with the scab-susceptible 'Gala'. Similar results for resistance and expression analysis were obtained also for the third line, although it was impossible to determine the copy number and TDNA integration site-such molecular characterization is requested by the ( EC) Regulation No. 1829/2003, but may become unnecessary if cisgenic crops become exempt from GMO regulation. [ABSTRACT FROM AUTHOR]

The synthesis of anthocyanin, the xanthophyll cycle, the antioxidant system and the production of active oxygen species (AOS) were compared between red and non‐red apple cultivars, in response to either long‐term sunlight exposure (high light intensity) during fruit development, or to exposure of bagged fruits to lower light intensity late in fruit development. During fruit development of red and non‐red apples, the xanthophyll cycle pool size decreased much more in red apple peel late in development. With accumulation of AOS induced by long‐term sunlight exposure, enhancement of the antioxidant system was found. However, this change became significantly lower in red apple than non‐red apple as fruit developed, which might serve to accelerate the anthocyanin synthesis in red apple peel. When, late in fruit development, bagged fruits were exposed to sunlight, the accumulation of AOS was lower in red apple peel than in non‐red peel. This could be due to the higher anthocyanin concentration in the red peels. Meanwhile, compared with that in non‐red cultivar, the xanthophyll cycle and the antioxidant system in red apple peel were protected first but then down‐regulated by its higher anthocyanin concentration during sunlight exposure. In conclusions, red and non‐red apples peel possess different photoprotective mechanisms under high light conditions. The relationship between anthocyanin synthesis and the xanthophyll cycle, and the antioxidant system, depends on the light conditions that fruit undergoes. [ABSTRACT FROM AUTHOR]

Crop-to-wild gene flow have important evolutionary and ecological consequences and require careful consideration in conservation programs for wild genetic resources of potential use in breeding programs and in assessments of the risk of transgene escape into natural ecosystems. Using 26 microsatellites and a set of 1181 trees, we investigated the extent of introgression from the cultivated apple, Malus domestica, to its three closest wild relatives, M. sylvestris in Europe, M. orientalis in the Caucasus, and M. sieversii in Central Asia. We found footprints of introgression from M. domestica to M. orientalis (3.2% of hybrids), M. sieversii (14.8%), and M. sylvestris (36.7%). Malus sieversii and M. orientalis presented weak, but significant genetic structures across their geographic range. Malus orientalis displayed genetic differentiation with three differentiated populations in Turkey, Armenia, and Russia. Malus sieversii consisted of a main population spread over Central Asia and a smaller population in the Tian Shan Mountains. The low Sp values suggest high dispersal capacities for the wild apple relatives. High potential for crop-to-wild gene flow in apples needs to be considered in the implementation of in situ and ex situ actions for the conservation of wild apple genetic resources potentially useful to plant breeding. [ABSTRACT FROM AUTHOR]

Consumers of whole foods, such as fruits, demand consistent high quality and seek varieties with enhanced health properties, convenience or novel taste. We have raised the polyphenolic content of apple by genetic engineering of the anthocyanin pathway using the apple transcription factor MYB10. These apples have very high concentrations of foliar, flower and fruit anthocyanins, especially in the fruit peel. Independent lines were examined for impacts on tree growth, photosynthesis and fruit characteristics. Fruit were analysed for changes in metabolite and transcript levels. Fruit were also used in taste trials to study the consumer perception of such a novel apple. No negative taste attributes were associated with the elevated anthocyanins. Modification with this one gene provides near isogenic material and allows us to examine the effects on an established cultivar, with a view to enhancing consumer appeal independently of other fruit qualities. [ABSTRACT FROM AUTHOR]

Understanding how pathogens evolve according to pressures exerted by their plant hosts is essential for the derivation of strategies aimed at the durable management of resistant cultivars. The spectrum of action of the resistance factors in the partially resistant cultivars is thought to be an important determinant of resistance durability. However, it has not yet been demonstrated whether the pressures exerted by quantitative resistance are different according to their spectrum of action., To investigate selection pressures exerted by apple genotypes harbouring various resistance quantitative trait loci ( QTLs) on a mixed inoculum of the scab disease agent, Venturia inaequalis, we monitored V. inaequalis isolate proportions on diseased apple leaves of an F1 progeny using quantitative pyrosequencing technology and QTL mapping., Broad-spectrum resistances did not exert any differential selection pressures on the mixed inoculum, whereas narrow-spectrum resistances decreased the frequencies of some isolates in the mixture relative to the susceptible host genotypes., Our results suggest that the management of resistant cultivars should be different according to the spectrum of action of their resistance factors. The pyramiding of broad-spectrum factors or the use of a mixture of apple genotypes that carry narrow-spectrum resistance factors are two possible strategies for the minimization of resistance erosion. [ABSTRACT FROM AUTHOR]

Mitochondrial genomes of spermatophytes are the largest of all organellar genomes. Their large size has been attributed to various factors; however, the relative contribution of these factors to mitochondrial DNA (mtDNA) expansion remains undetermined. We estimated their relative contribution in Malus domestica (apple). The mitochondrial genome of apple has a size of 396 947 bp and a one to nine ratio of coding to non-coding DNA, close to the corresponding average values for angiosperms. We determined that 71.5% of the apple mtDNA sequence was highly similar to sequences of its nuclear DNA. Using nuclear gene exons, nuclear transposable elements and chloroplast DNA as markers of promiscuous DNA content in mtDNA, we estimated that approximately 20% of the apple mtDNA consisted of DNA sequences imported from other cell compartments, mostly from the nucleus. Similar marker-based estimates of promiscuous DNA content in the mitochondrial genomes of other species ranged between 21.2 and 25.3% of the total mtDNA length for grape, between 23.1 and 38.6% for rice, and between 47.1 and 78.4% for maize. All these estimates are conservative, because they underestimate the import of non-functional DNA. We propose that the import of promiscuous DNA is a core mechanism for mtDNA size expansion in seed plants. In apple, maize and grape this mechanism contributed far more to genome expansion than did homologous recombination. In rice the estimated contribution of both mechanisms was found to be similar. [ABSTRACT FROM AUTHOR]

Thirty-one potential miRNAs that belong to 16 miRNA families were discovered from more than 324 000 EST sequences of apple (Malus domestica). In addition, precise sequences, especially terminal nucleotides of the 16 apple miRNAs (mdo-miRNAs) in 16 families were validated by miR-RACE, a newly developed method for the determination of the potential miRNAs predicted computationally. The expression of these 16 microRNAs could be detected in apple young leaf, old leaf, young stem, flower bud, flower and developing fruits by quantitative RT-PCR (qRT-PCR) and some of them showed tissue-specific expression. Fifty-six potential targets were identified for the 16 apple miRNAs, most of which were transcription factors that play important roles in apple development. Twelve target genes were experimentally verified by qRT-PCR, with some exhibiting different expression trends from their corresponding microRNAs, indicating the cleavage mode of miRNAs on their target genes. [ABSTRACT FROM AUTHOR]

BSTRACT: Development of fresh-cut apple products requires consideration of cultivars that store well as both intact and fresh-cut fruit. We compared the instrumental and sensory quality of 2 apple cultivars, Granny Smith and Fuji, that are used for fresh cutting with 2 new cultivars, Pink Lady and GoldRush, which were considered to have quality characteristics suitable for fresh cutting. Firmness, titratable acidity (TA), soluble solids content (SSC), and aromatic volatile concentration were measured in intact fruit of the 4 cultivars during 12 mo storage in air at 0 °C and during 3 wk storage at 5 °C as fresh-cut slices. After 1 wk storage as fresh-cut slices, sensory evaluations for acceptability of flesh and peel appearance, flavor, texture, and overall eating quality were performed. During storage, GoldRush apples maintained > 80 N firmness, approximately 17% SSC, > 0.5% TA, and had high aromatic volatile production, that is, maintained quality better than the other cultivars. The quality and shelf stability of GoldRush slices were also as good as or better than slices from the other cultivars, whereas Granny Smith slices generally rated lower than the other cultivars. The acceptability of flavor, texture, and overall eating quality of GoldRush slices was as good as that for Pink Lady and Fuji. The quality of GoldRush apples can be maintained throughout the year in refrigerated air storage and still remain suitable for fresh-cut processing. The results indicate that GoldRush and Pink Lady are 2 promising new, high-quality apple cultivars for fresh cutting. Keywords: fresh-cut fruit, Malus × domestica, postharvest quality, respiration rate, shelf life [ABSTRACT FROM AUTHOR]

Investigates the origin of apple subfamily Maloideae Rosaceae using DNA sequencing data from granule bound starch synthase genes. Lineage containing the ancestors of Gillenia; Features of the evolution of the Maloideae; Association of the fungal pathogen, floral morphology and fossil flowers with the origin of Maloideae.

Haploids in apple were induced using anther culture and in situ parthenogenesis followed by in vitro culture of immature embryos or cotyledons. In addition to an earlier characterization of the zygosity state using isozymes, the purpose of this work was an analysis of simple sequence repeats (SSRs) to describe the homozygosity more comprehensively. Five previously described SSR primer combinations were applied. Initially, polymerase chain reaction amplification with the primer pairs was performed on the donor genotypes `Alkmene' and `Remo' and on a further four apple cultivars. Only those primer pairs that amplified two different contrasting alleles could be used for investigation of the zygosity state. According to these analyses both the androgenic and parthenogenic regenerated shoots are homozygous. [ABSTRACT FROM AUTHOR]