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Scegliere le zone più idonee per la coltivazione di una determinata varietà è una decisione difficile e di ampio spettro che coinvolge non solo gli agricoltori, ma tutta la filiera coinvolta nel processo, dalla produzione alla vendita. La scelta varietale ha ripercussioni economiche di lungo termine. In tale prospettiva, con KULTIVAS vorremmo proporre un approccio data-driven a questo importante problema del settore melicolo. In questo progetto, dati storici selezionati sulla produttività e qualità delle mele, moderni sistemi di gestione dei dati, algoritmi e tecniche di apprendimento automatico sono stati impiegati adottando un approccio multidisciplinare che coinvolge esperti di diversi settori, quali agronomia, fisiologia, climatologia e informatica, per valutare l'idoneità sito- specifica alla coltivazione di determinate varietà di mele. Il modello di previsione sviluppato nell’ambito del progetto si basa su dati climatici e topografici interpolati spazialmente, oltre che su dati di produzione e qualità delle mele provenienti da diverse cooperative altoatesine. Usando informazioni spazialmente disponibili sul clima, il modello è in grado di stimare vari parametri di produzione, come calibro, colore e resa. La previsione degli indicatori predetti dal modello statistico è più̀ precisa quanto più̀ il set di dati di training copre la variabilità̀ climatica e topografica delle aree di indagine. In aree con caratteristiche al di fuori di questa variabilità, il modello avrà un potere predittivo limitato. I risultati di questo studio saranno arricchiti con dati provenienti da altre località e valutando ulteriori algoritmi per la corrispondenza geografica dei dati di cernita, in quanto il set di dati influenza in maniera importante i risultati.

Apple (Malus × domestica Borkh.) is the most widely grown permanent fruit crop of temperate climates. Although commercial apple growing is based on a small number of globally spread cultivars, its diversity is much larger and there are estimates about the existence of more than 10,000 documented varieties. The varietal diversity can be described and determined based on phenotypic characters of the external and internal traits of fruit, which, however, can be modulated by environmental factors. Consequently, molecular methods have become an important alternative means for the characterisation of apple cultivar diversity. In order to use multilocus microsatellite data for determination of unidentified or misidentified apple varieties, a database with molecular genetic fingerprints of well-determined reference cultivars needs to be available. The objective of the present work was to establish such a database that could be applied for the molecular genetic determination of a large number of historic and modern, diploid and triploid apple cultivars. Based on the analysis of more than 1600 accessions of apple trees sampled in 37 public and private cultivar collections in different European countries at 14 variable microsatellite loci, a database with 600 molecular genetic profiles was finally obtained. The key criterion for considering a molecular genetic profile as confirmed and for including it into the reference database was that at least two accessions of the same cultivar of different provenances generated an identical result, which was achieved for 98% of the apple cultivars present in the database. For the remaining genotypes, the cultivar assignment was supported by a parentage analysis or by comparison to molecular genetic profiles available in published works. The database is composed of 574 scion cultivars, 24 rootstock genotypes and two species of crab apples. Of the 574 scion cultivars, 61% were derived from historic or old cultivars, many of which were grown in Central Europe in the past. The remaining scion cultivars are currently grown or available in testing programmes and may gain importance in the future. In order to validate the genotyping data, parentage analysis was performed involving cultivars and rootstocks that arose after 1900, for which information about at least one parent cultivar was available from pomological and scientific literature and the molecular genetic profiles of the assumed parent(s) were also present in our database. This analysis revealed the presence of null alleles at locus COL, however, when excluding this locus, a mean genotyping error rate of only 0.28% per locus was revealed, which points to a high reliability of the dataset. The datasets with 14 and 13 loci (excluding locus COL) showed a high degree of discrimination power, with a combined non-exclusion probability of identity of 2.6 × 10−20 and 3.4 × 10−19. Five of the microsatellite loci analysed in the present study overlapped with another published dataset and after the application of conversion values, it was possible to align the allele lengths and compare the molecular genetic profiles of 20 randomly derived cultivars, which were analysed in both studies. This comparison evidenced an exact correspondence of the microsatellite profiles contained in the two datasets, further pointing to the accuracy of our database. Apart from its application to characterise genetic resources or to manage germplasm collections, the here presented database could serve as an important tool for quality control or as a useful instrument in breeding programmes.

The analysis of selected phenolic compounds in dried apple pulps with pentafluorophenyl (PFP) reversed-phase HPLC-UV-FL is presented. Three new apple cultivars named Nicoter Kanzi®, Shinano Gold yello®, and the red-fleshed one Luresweet Redlove® grown in one site in South Tyrol (Italy) have been investigated and compared with cv. Golden Delicious. Phenolics belonging to different classes (hydroxybenzoic acids, flavan-3-ols, caffeoylquinic derivatives, flavonols, and dihydrochalcones) have been analyzed. Extraction with aqueous methanolic mixture yielded good analytical recovery. Luresweet Redlove® showed the highest content of quercetin-3-O-glucoside, gallic acid, and chlorogenic acid and the lowest content of catechins and procyanidins; on the other hand, Nicoter Kanzi® showed the lowest concentration of quercetin-3-O-glucoside. The analytical procedure described is an easy and affordable methodology to investigate other apple varieties from local cultivations, to study their phytochemical composition, and to determine their potential nutraceutical values. The content of phenolic compounds in the three apple varieties Nicoter Kanzi®, Shinano Gold yello®, and Luresweet Redlove® was reported for the first time.

Implementation of genomic tools is desirable to increase the efficiency of apple breeding. Recently, the multi-environment apple reference population (apple REFPOP) proved useful for rediscovering loci, estimating genomic predictive ability, and studying genotype by environment interactions (G × E). So far, only two phenological traits were investigated using the apple REFPOP, although the population may be valuable when dissecting genetic architecture and reporting predictive abilities for additional key traits in apple breeding. Here we show contrasting genetic architecture and genomic predictive abilities for 30 quantitative traits across up to six European locations using the apple REFPOP. A total of 59 stable and 277 location-specific associations were found using GWAS, 69.2% of which are novel when compared with 41 reviewed publications. Average genomic predictive abilities of 0.18-0.88 were estimated using main-effect univariate, main-effect multivariate, multi-environment univariate, and multi-environment multivariate models. The G × E accounted for up to 24% of the phenotypic variability. This most comprehensive genomic study in apple in terms of trait-environment combinations provided knowledge of trait biology and prediction models that can be readily applied for marker-assisted or genomic selection, thus facilitating increased breeding efficiency., This work was partially supported by the project RIS3CAT (COTPA-FRUIT3CAT) financed by the European Regional Development Fund through the FEDER frame of Catalonia 2014-2020 and by the CERCA Program from Generalitat de Catalunya. We acknowledge financial support from the Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa Programme for Centres of Excellence in R&D” 2016-2019 (SEV-20150533) and 2020-2023 (CEX2019-000902-S)., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000902-S)

Implementation of genomic tools is desirable to increase the efficiency of apple breeding. The apple reference population (apple REFPOP) proved useful for rediscovering loci, estimating genomic prediction accuracy, and studying genotype by environment interactions (G×E). Here we show contrasting genetic architecture and genomic prediction accuracies for 30 quantitative traits across up to six European locations using the apple REFPOP. A total of 59 stable and 277 location-specific associations were found using GWAS, 69.2% of which are novel when compared with 41 reviewed publications. Average genomic prediction accuracies of 0.18–0.88 were estimated using single-environment univariate, single-environment multivariate, multi-environment univariate, and multi-environment multivariate models. The G×E accounted for up to 24% of the phenotypic variability. This most comprehensive genomic study in apple in terms of trait-environment combinations provided knowledge of trait biology and prediction models that can be readily applied for marker-assisted or genomic selection, thus facilitating increased breeding efficiency.

Eine geeignete Pollenspendersorte muss nicht nur einen kompatiblen Pollen zur Hauptsorte aufweisen, sondern die Blühperiode beider Sorten sollte sich auch ausreichend überschneiden. Der Blühtermin ist entscheidend für die Befruchtung der Apfelblüte und beeinflusst somit den Ertrag und die Fruchtqualität. Es stellt sich unter anderem die Frage, ob neue vielversprechende Sorten wie z.B. Minneiska (SweeTango®) oder WA 38 (Cosmic Crisp®) mit den Südtiroler Hauptsorten wie Gala, Golden Delicious oder Cripps Pink (Pink Lady®) eine ausreichende Überschneidung der Blühperiode aufweisen und somit ohne zusätzlichen Pollenspender angebaut werden können. Am Versuchszentrum Laimburg wurden die Blühtermine von 236 verschiedenen Apfelsorten mit einer standardisierten Methode erhoben. Es handelt sich dabei um alte Lokalsorten, die aktuellen Hauptsorten und neue Sorten. Die in dieser Zusammenfassung berücksichtigten Erhebungen wurden von 2010-2020 sowohl am Standorten Laimburg auf 220 m ü. NN, als auch am Standort Latsch auf 670 m ü. NN durchgeführt. Das Ergebnis ist eine fundierte Kategorisierung von rund 200 Apfelsorten aufgrund ihres relativen Blühtermins. Die klimatischen Bedingungen beeinflussen bekanntlich die Blühdauer stark, was sich auch in den Ergebissen an den unterschiedlichen Standorten und Jahren widerspiegelte.

Für einen Zeitraum von 8 Jahren wurde die vom Institut NIAB-EMR (East Malling, UK) stammende Unterlage M200 in einem Gemeinschaftsversuch zwischen dem „Versuchszentrum Laimburg“ (Italien) und dem „Dienstleistungszentrum Ländlicher Raum Rheinpfalz“ in Klein-Altendorf (Deutschland) geprüft. Ein positiver Aspekt der Unterlage sind ihre höheren Baumerträge im Vergleich zu M9 T337, bei einer ähnlichen Fruchtqualität. Die glatte Oberfläche der Unterlage ist fast frei von Wurzelfeldern. Auch Wurzelaustriebe sind sehr selten im Unterschied zu M9 T337. M200 hat keine höhere Toleranz gegenüber Bodenmüdigkeit gezeigt als M9 T337: Vor allem im Pflanzjahr und im 2. Standjahr wurden Wachstums- und Ertragsdefizite auf unbehandeltem Boden festgestellt, ähnlich wie bei M9 T337, G 11 und G 41. M200 wächst am Versuchszentrum Laimburg allerdings signifikant stärker als M9 T337, was im Nachbau oder in Kombination mit schwachwüchsigen Sorten von Vorteil sein kann. In Klein-Altendorf liegt M200 in der Wüchsigkeit um M9 T337, wobei anzumerken ist, dass die neue Unterlage in den ersten 4 Standjahren höhere Triebzuwächse als M9 T337 erreicht. G 11 ist im Vergleich zu M200 in beiden Versuchen als schwächer einzustufen. Diese Divergenz der Resultate auf beiden Standorten bestätigt, dass in der Bewertung von Unterlagen Interaktionen zwischen Unterlage, Boden und klimatischen Bedingungen berücksichtigt werden müssen.

Die meisten Konsumenten interessieren sich immer stärker für die Herkunft ihrer Lebensmittel. Eine vielversprechende Methode, um die Herkunft von landwirtschaftlichen Produkten zu prüfen ist die Analyse des Strontium (87Sr/86Sr)-Isotopenverhältnisses. Das 87Sr/86Sr-Verhältnis einer Pflanze spiegelt jenes des Bodens auf dem sie wächst wider. Der folgende Beitrag zeigt einige Aspekte des 87Sr/86Sr-Verhältnisses, untersucht während eines 3-jährigen Projektes, und seiner Verwendung als geographischen Indikator für Äpfel auf. In einem ersten Experiment betrachteten wir den Einfluss von landwirtschaftlichen Praktiken und des dadurch extern eingebrachten Strontiums, auf das Isotopenverhältnis der Apfelbäume im Gewächshaus. Die Bäume passten sich langsam an das Isotopenverhältnis im Boden an. Die landwirtschaftlichen Anwendungen hatten nur einen geringen Einfluss auf das 87Sr/86Sr-Verhältnis der Pflanze. Im zweiten Experiment wurden Unterschiede im Isotopenverhältnis zwischen Teilproben eines Pflanzenbestandteiles derselben Pflanze („intra-part“), Unterschiede zwischen den verschiedenen Pflanzenbestandteilen desselben Baumes („intra-tree“), die Unterschiede zwischen den verschieden Pflanzenbestandteilen unterschiedlicher Bäume derselben Obstanlage („inter-tree“) und ihr Zusammenhang mit dem Isotopenverhältnis im Boden, in jeweils zwei Südtiroler Obstanlagen untersucht. „Intra-part“ und „intra-tree“ war das 87Sr/86Sr Verhältniss homogen, allerdings konnten wir Unterschiede zwischen den Bäumen („inter-tree“) der beiden Obstanlagen beobachten. Im letzten Experiment wurden die Analysen auf 41 Obstanlagen in Norditalien ausgeweitet. Das 87Sr/86Sr-Verhältnis von Äpfeln mit geographischer Kennzeichnung aus verschiedenen Gebieten, wurde mit jenen ohne Kennzeichnung verglichen. Das Isotopenverhältnis im Apfel korrelierte stark mit jenem des jeweiligen Bodens der entsprechenden Obstanlage. Einige Gebiete hatten ähnliche geologische Eigenschaften und Isotopenverhältnis, wodurch eine eindeutige Unterscheidung nicht für alle Ortschaften möglich war. Trotzdem kann das 87Sr/86Sr-Verhältnis als geographischer Indikator verwendet werden, jedoch sollten in zukünftigen Studien weitere Parameter miteinbezogen werden.

International audience; This study provides cultivar-specific metabolic fingerprints of volatile organic compounds in the headspace of cloudy apple juices. Cloudy juices from 47 "true to type" apple cultivars grown under identical agricultural and climatic conditions in South Tyrol, Italy, have been analysed through headspace solid-phase microextraction gas chromatography coupled with high-resolution time-of-flight mass spectrometry (HS-SPME/GC-HRTOF-MS), yielding cultivar-specific volatile organic compound (VOC) profiles. Apple cultivars included 10 old cultivars with local relevance, 18 commercial cultivars, dominating the current international market, 10 scab-resistant and 9 red-fleshed ones. The 28 most abundant VOCs were found in the whole dataset, indicating a remarkable chemodiversity within juices. The main discriminant metabolites were butyl acetate; pentyl acetate; 2-methylbutyl acetate; pentan-1-ol; hexan-1-ol; n-hexanal and (E)-2-hexenal. A principal component analysis (PCA) and a hierarchical cluster analysis (HCA) have not identified a clear separation of the analysed cultivar classes. Nevertheless, a series of scab-resistant and red-fleshed cultivars with VOC profiles similar to established commercial cultivars were identified; these data could help substituting current cultivars with more sustainable ones. On a more general basis, our study supports a knowledge-driven selection of apple cultivars for specific consumer preferences and helps appreciating the biodiversity of apples across old local and more recent (scab-resistant and red-fleshed) cultivars.

International audience; Apple scab, caused by Venturia inaequalis, is a major disease worldwide. To control this disease, up to 20-25 fungicide applications may be needed depending on the year and the production system. Cultivation of scab-resistant apple cultivars would reduce the chemical footprint of apple production. Breeding for durable scab resistance is an objective of most apple breeding programmes. One way to achieve durable resistance is to pyramid multiple apple scab resistance genes in a cultivar. Currently, more than 18 different apple scab resistance genes have been reported. Molecular markers are available for most of these and can be used to select seedlings carrying multiple resistance genes. Apple scab isolates are virulent to specific apple scab resistance genes. Choice of optimal resistance genes for use in a breeding program, should therefore take regional presence of these apple scab isolates into consideration. In order to learn more about the geographical distribution of apple scab isolates, the VINQUEST project (www.vinquest.ch) was initiated in 2009. Ten years after the launch of this initiative, 24 partners from 14 countries are regularly contributing data. Results obtained from the data collected during the first 10 years provide the first insights into which apple scab resistance genes may hold most promise for breeding cultivars with durable resistance.

Die Durchführung von manuellen Ertragsschätzungen ist meist mit einem hohen Arbeitsaufwand und hohen Kosten verbunden. Mithilfe von modernen Bilderkennungssystemen ist es bereits möglich Ertragsprognosen zu erstellen, um flächenbezogene Ertragsleistung und die Fruchtgrößenverteilung zu ermitteln. Dadurch können Kulturmaßnahmen zielgerichteter eingesetzt und die Lagerung sowie die Logistik optimiert werden. Deshalb wurden in dieser Arbeit-fünf verschiedene kommerziell erhältliche Systeme auf ihre Genauigkeit und Praxistauglichkeit bei verschiedenen Sorten und auf verschiedenen Standorten getestet. Dafür wurden die erhaltenen Daten mit manuell ermittelten Daten verglichen und die Abweichung berechnet. Dabei wurde festgestellt, dass große Unterschiede zwischen den verschiedenen Systemen vorlagen, wobei einige Systeme bereits eine ausreichende Genauigkeit aufwiesen. Beim Großteil der Systeme waren jedoch zu große Abweichungen vorhanden und dafür aufgebrachte Zeitaufwand für die Erfassung der Daten lag häufig über dem der manuellen Messung.

Breeding of apple is a long-term and costly process due to the time and space requirements for screening selection candidates. Genomics-assisted breeding utilizes genomic and phenotypic information to increase the selection efficiency in breeding programs, and measurements of phenotypes in different environments can facilitate the application of the approach under various climatic conditions. Here we present an apple reference population: the apple REFPOP, a large collection formed of 534 genotypes planted in six European countries, as a unique tool to accelerate apple breeding. The population consisted of 269 accessions and 265 progeny from 27 parental combinations, representing the diversity in cultivated apple and current European breeding material, respectively. A high-density genome-wide dataset of 303,239 SNPs was produced as a combined output of two SNP arrays of different densities using marker imputation with an imputation accuracy of 0.95. Based on the genotypic data, linkage disequilibrium was low and population structure was weak. Two well-studied phenological traits of horticultural importance were measured. We found marker–trait associations in several previously identified genomic regions and maximum predictive abilities of 0.57 and 0.75 for floral emergence and harvest date, respectively. With decreasing SNP density, the detection of significant marker–trait associations varied depending on trait architecture. Regardless of the trait, 10,000 SNPs sufficed to maximize genomic prediction ability. We confirm the suitability of the apple REFPOP design for genomics-assisted breeding, especially for breeding programs using related germplasm, and emphasize the advantages of a coordinated and multinational effort for customizing apple breeding methods in the genomics era., This work was partially supported by the project RIS3CAT (COTPA-FRUIT3CAT) financed by the European Regional Development Fund through the FEDER frame of Catalonia 2014–2020 and by the CERCA Program from Generalitat de Catalunya. We acknowledge financial support from the Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa Program for Centres of Excellence in R&D” 2016–2019 (SEV‐20150533). This work has been partially funded by the EU seventh Framework Program, the FruitBreedomics project No. 265582: Integrated Approach for Increasing Breeding Efficiency in Fruit Tree Crops.

Die Arbeitsgruppe der Sorten- und Unterlagenprüfer Apfel und Birne aus dem EUFRIN Netzwerk (European Fruit Research Institutes Network) führt jährlich Bestäubungsversuche unter Anwendung einer standarisierten Methode durch. Seit dem Jahr 2002 tauschen neben dem Versuchszentrum Laimburg (Italien) die Institute Agroscope (Schweiz), Esteburg Obstbauzentrum Jork (Deutschland) und Pcfruit (Belgien) ihre Ergebnisse aus. Eine Zusammenfassung aller Daten ermöglicht es, für eine Reihe von neuen Apfelsorten wie beispielsweise MC 38 Crimson Snow®, Nicoter Kanzi®, Scifresh Jazz® oder Scilate Envy® “geeignete” und “ungeeignete” Pollenspender zu definieren. Der Bestäubungserfolg wird über die Ermittlung des Fruchtansatzes erhoben. Parallel dazu gibt die Samenanzahl Aufschluss über die Qualität der Bestäubung. Eine sich möglichst überlappende Blüte ist unter natürlichen Bedingungen Vorraussetzung für eine optimale Befruchtung, weshalb die jeweiligen Blütezeiten in den Tabellen der Pollenspender integriert sind.

International audience; Apple scab, caused by Venturia inaequalis, is a major fungal disease worldwide. Cultivation of scab-resistant cultivars would reduce the chemical footprint of apple production. However, new apple cultivars carrying durable resistances should be developed to prevent or at least slow the breakdown of resistance against races of V. inaequalis. One way to achieve durable resistance is to pyramid multiple scab resistance genes in a cultivar. The choice of the resistance genes to be combined in the pyramids should take into account the frequency of resistance breakdown and the geographical distribution of apple scab isolates able to cause such breakdowns. In order to acquire this information and to make it available to apple breeders, the VINQUEST project (www.vinquest.ch) was initiated in 2009. Ten years after launching this project, 24 partners from 14 countries regularly contribute data. From 2009 to 2018 nearly 9000 data points have been collected. This information has been used to identify the most promising apple scab resistance genes for developing cultivars with durable resistance, which to date are: Rvi5, Rvi11, Rvi12, Rvi14 and Rvi15. As expected, Rvi1, together with Rvi3 and Rvi8, were often overcome, hence have little value for scab resistance breeding. Rvi10 may also belong to this group. On the other hand Rvi2, Rvi4, Rvi6, Rvi7, Rvi9, and Rvi13 are still useful for the breeding, but their use is recommended only in extended pyramids of (≥3) resistance genes.

Una nueva Revista de Derecho se presenta en esta edición, con muy buenos trabajos de doctrina que abordan aspectos trascendentes en distintas áreas del Derecho. Sin embargo, esta edición se vio también implicada en el hecho de mayor significancia actual: la pandemia por COVID-19.

The aromatic profile of apples constitutes important information for the characterization and description of local products. Apple flavor is determined by perception in mouth and aroma, while the first is mainly defined by sugars and organic acids, aroma is a complex mixture of many volatile organic compounds (VOCs) whose composition is often specific to the variety. Headspace-solid phase microextraction gas chromatography coupled with mass spectrometry (HS-SPME-GC-MS) allows for the detection of detailed information of volatile constituents. In this study, eleven apple varieties (Braeburn, Fuji, Gala, Golden Delicious, Coop 39-Crimson Crisp&reg, Dalinette-Choupette&reg, Fujion, CIV323-Isaaq&reg, Coop43-Juliet&reg, SQ159-Natyra&reg, UEB32642-Opal&reg, ) grown in two pedoclimatic locations at different altitudes in South Tyrol (Italy) (ca. 225 m and ca. 650 m a.s.l.) were investigated. Thirty-eight VOCs were identified and combined with sensory analysis results (from 11 trained panelist) to characterize the aroma of new and standard apple varieties with a special focus on pedoclimatic location differences. The study shows strong diversification of the varieties based on their VOC profiles and sensory attributes, as expected. Moreover, investigating how the pedoclimatic location at different altitudes can influence the apple aroma profile, we identified twelve VOCs involved in these differences and provided a deeper investigation on how different altitudes can influence the apple aroma composition and perceptions combining the analytical and sensory parameters.

Plants have evolved a range of adaptive mechanisms that adjust their development and physiology to variable external conditions, particularly in perennial species subjected to long-term interplay with the environment. Exploiting the allelic diversity within available germplasm and leveraging the knowledge of the mechanisms regulating genotype interaction with the environment are crucial to address climatic challenges and assist the breeding of novel cultivars with improved resilience. The development of multisite collections is of utmost importance for the conservation and utilization of genetic materials and will greatly facilitate the dissection of genotype-by-environment interaction. Such resources are still lacking for perennial trees, especially with the intrinsic difficulties of successful propagation, material exchange, and living collection maintenance. This work describes the concept, design, and realization of the first multisite peach (Prunus persica) reference collection (PeachRefPop) located across different European countries and sharing the same experimental design. Other than an invaluable tool for scientific studies in perennial species, PeachRefPop provides a milestone in an international collaborative project for the conservation and exploitation of European peach germplasm resources and, ultimately, as a true heritage for future generations.

Texture is a complex trait and a major component of fruit quality in apple. While the major effect of MdPG1, a gene controlling firmness, has already been exploited in elite cultivars, the genetic basis of crispness remains poorly understood. To further improve fruit texture, harnessing loci with minor effects via genomic selection is therefore necessary. In this study, we measured acoustic and mechanical features in 537 genotypes to dissect the firmness and crispness components of fruit texture. Predictions of across-year phenotypic values for these components were calculated using a model calibrated with 8,294 SNP markers. The best prediction accuracies following cross-validations within the training set of 259 genotypes were obtained for the acoustic linear distance (0.64). Predictions for biparental families using the entire training set varied from low to high accuracy, depending on the family considered. While adding siblings or half-siblings into the training set did not clearly improve predictions, we performed an optimization of the training set size and composition for each validation set. This allowed us to increase prediction accuracies by 0.17 on average, with a maximal accuracy of 0.81 when predicting firmness in the ‘Gala’ × ‘Pink Lady’ family. Our results therefore identified key genetic parameters to consider when deploying genomic selection for texture in apple. In particular, we advise to rely on a large training population, with high phenotypic variability from which a ‘tailored training population’ can be extracted using a priori information on genetic relatedness, in order to predict a specific target population.

The present work was designed to compare the vitamin C (ascorbic acid, AsA) content of pulp, peel, and juice of 64 apple cultivars. These cultivars were carefully identified as ‘true to type’ by molecular genetic tools, grown in the same site under identical conditions and processed by a standardized protocol. Twenty-one of them, accounting for more than 95% of the apple production of South Tyrol, were chosen to represent the current market, 16 were old or local cultivars formerly grown in the area, and 27 were new cultivars, including 15 with scab resistance and 12 with red flesh fruit. For the determination of the AsA content, a new High-Performance Liquid Chromatography with Diode-Array Detection method was developed and validated. While old cultivars stood out for their high AsA content in pulp and peel, the red-fleshed cultivars are the ones maintaining most of their AsA content during processing. Our data thus suggest a potential for old and red-fleshed cultivars for healthy juices or further processed food components.

Apple is one of the most widely produced and consumed fruits worldwide and hence, complete data of apple composition are important for human diet. Currently, a limited number of cultivars dominate the market, while many others, with a potentially higher nutritional value, are neglected by consumers. The present work reports the content of the dietary elements potassium (K), phosphorus (P), calcium (Ca) and magnesium (Mg) as well as the content of the macroelement nitrogen (N) of 34 old cultivars grown at the same site under identical conditions in South Tyrol, Italy. Their elemental composition was assessed along with quality parameters such as fruit weight, firmness, and soluble solid content and total acidity at harvest and post storage. For selected cultivars the measurements were performed over two or even three different harvest years. Comparison with eight commercial cultivars chosen to represent the fruit currently dominating the market was performed. Besides offering a valuable insight in the variation of dietary elements among old and commercial apple cultivars in up to three harvest years, this study, that complements current nutritional databases, recommends several old cultivars with high content of dietary elements for further study and eventual re-introduction in niche markets.

Am Land- und Forstwirtschaftlichen Versuchszentrum Laimburg wurde in den Jahren von 2007 bis 2013 das spezifische Gewicht von 121 Apfelsorten aus der eigenen Sortensammlung mittels hydrostatischer Methode (Archimedisches Prinzip) ermittelt. Dazu wurde jahrlich im selben Zeitraum eine Stichprobenanzahl von 10 Apfeln pro Sorte mit einer einheitlichen sortentypischen Fruchtgrose untersucht. Die Sorten stammten vorwiegend von den Standorten Laimburg (220 m Meereshohe) und Latsch (700 m Meereshohe). Mit den Messdaten wurde eine Klasseneinteilung nach 4 spezifischen Gewichtskategorien von 0,75 bis 0,91 g/cm3 vorgenommen. 76 % der Sorten gliederten sich in die mittleren Kategorien ein, da sie spezifische Gewichtsgrosen von 0,80 bis 0,86 g/cm3 aufwiesen. Bei den spezifisch „sehr leichten“ Sorten war zum Beispiel ‘Golden Delicious’ enthalten und bei den spezifisch „sehr schweren“ Sorten ‘Braeburn’, ‘Nicoter Kanzi®’ und ‘Scifresh Jazz®’. Das spezifische Gewicht verandert sich kaum durch Jahres- oder Standorteinflusse, da es vielmehr von vorwiegend genetisch bedingten Merkmalen wie beispielsweise dem Interzellularvolumen und dem Trockensubstanzgehalt der Frucht abhangig ist. Auch Fruchtgrose und Reifegrad zahlen zu den Einflussfaktoren. Das spezifische Gewicht ist eine interessante Zusatzinformation zur Beschreibung einer Apfelsorte.

Texture plays a major role in the determination of fruit quality in apple. Due to its physiological and economic relevance, this trait has been largely investigated, leading to the fixation of the major gene PG1 controlling firmness in elite cultivars. To further improve fruit texture, the targeting of an undisclosed reservoir of loci with minor effects is compelling. In this work, we aimed to unlock this potential with a genomic selection approach by predicting fruit acoustic and mechanical features as obtained with a TA.XTplus texture analyzer in 537 individuals genotyped with 8,294 SNP markers. The best prediction accuracies following cross-validations within the training set (TRS) of 259 individuals were obtained for the acoustic linear distance (0.64). Prediction accuracy was further improved through the optimization of TRS size and composition according to the test set. With this strategy, a maximal accuracy of 0.81 was obtained when predicting the synthetic trait PC1 in the family ‘Gala × Pink Lady’. We discuss the impact of genetic relatedness and clustering on trait variability and predictability. Moreover, we demonstrated the need for a comprehensive dissection of the complex texture phenotype and the potentiality of using genomic selection to improve fruit quality in apple.HighlightA genomic selection study, together with the optimization of the training set, demonstrated the possibility to accurately predict texture sub-traits valuable for the amelioration of fruit quality in apple.

Fruit quality is represented by a series of genetically controlled features that change throughout the entire ontogenic life. Among the several quality traits, texture plays a crucial role, impacting both consumers’ appreciation and postharvest performance. In order to decipher its regulation a multidisciplinary approach was employed. Initially, the texture performance was measured with a high resolution phenotyping device, represented by a texture analyzer equipped with an acoustic device. In the first attempt to dissect the fruit texture genetic control, two QTL mapping strategies were used. The first approach employed six bi-parental families linked by a common pedigree scheme, known as pedigree based analysis. The joint analysis of the phenotypic and genotypic data set through a Bayesian statistics identified a series of genomic regions related to both mechanical and acoustic signatures. These regions were further validated with a genome wide association study approach, which considered a much larger phenotypic and genotypic variation. To complement the genetic information, a whole transcriptome analysis was also carried out. To this end, two microarray platforms were designed and used to unravel the functional machinery ongoing during the fruit development and ripening phases, especially with regards to the plant hormone ethylene. In this study, the role of this hormone was dissected applying 1-MCP, a molecule competing with ethylene at receptor level. The combination of these resources provides a valuable source of information, essential to step forward in the comprehension of the genetic and physiological regulation of the fruit texture in apple. This knowledge would enable, in a close future, a more accurate and precise selection of the most favourable and valuable new apple accessions distinguished by a superior fruit quality.

Highlight A distinct set of QTLs related to mechanical and acoustic fruit texture features were identified in apple. Through a GWAS approach, the specific genetic control of these subtraits was elucidated., Fruit texture is a complex feature composed of mechanical and acoustic properties relying on the modifications occurring in the cell wall throughout fruit development and ripening. Apple is characterized by a large variation in fruit texture behavior that directly impacts both the consumer’s appreciation and post-harvest performance. To decipher the genetic control of fruit texture comprehensively, two complementing quantitative trait locus (QTL) mapping approaches were employed. The first was represented by a pedigree-based analysis (PBA) carried out on six full-sib pedigreed families, while the second was a genome-wide association study (GWAS) performed on a collection of 233 apple accessions. Both plant materials were genotyped with a 20K single nucleotide polymorphism (SNP) array and phenotyped with a sophisticated high-resolution texture analyzer. The overall QTL results indicated the fundamental role of chromosome 10 in controlling the mechanical properties, while chromosomes 2 and 14 were more associated with the acoustic response. The latter QTL, moreover, showed a consistent relationship between the QTL-estimated genotypes and the acoustic performance assessed among seedlings. The in silico annotation of these intervals revealed interesting candidate genes potentially involved in fruit texture regulation, as suggested by the gene expression profile. The joint integration of these approaches sheds light on the specific control of fruit texture, enabling important genetic information to assist in the selection of valuable fruit quality apple varieties.

Storage methods extend the postharvest life of apples from weeks to up to one year; however, these methods also alter the production of volatile organic compounds (VOCs), which amongst others, are important for aroma attributes. While the impact of storage on particular aroma components has been established, high throughput methods for determining the storage history during shelf-life are elusive. Here we show the potential of proton transfer reaction-mass spectrometry (PTR-MS), an MS-based metabolic fingerprinting technique, for characterizing fruit in the postharvest chain. The VOC fingerprint of apples (Malus × domestica Borkh. ‘Red Delicious’) was analyzed by PTR-MS during four weeks of shelf-life ripening after storage under four different storage conditions: ULO (ultra-low oxygen), DCA-CF (dynamic controlled atmosphere monitored by chlorophyll fluorescence), RLOS (repeated low oxygen stress) and 1-MCP (1-methylcyclopropene) in ULO. PTR fingerprint mass spectra of the apple headspace, obtained in short time without sample preparation or preconcentration, were sufficient to discriminate the four storage conditions during shelf-life. Moreover, we were able to monitor the changes in quality-critical VOC classes, including esters and terpenes, during shelf-life and observe the differential impact of the storage history on these VOCs. This work emphasizes the potential of PTR-MS as a valuable addition to targeted GC–MS-based approaches in postharvest research.

Molecular markers are nowadays considered fundamental tools in breeding programs, supporting the selection of the most favourable offspring. This role is invaluable in the case of complex agronomic traits in tree fruit crop species, such as fruit texture in apple (Malus × domestica Borkh.). This work presents the validation of a previously identified functional simple sequence repeat marker, named Md-PG1SSR10kd, suitable for the advanced selection of high texture performance seedlings. Two independent populations were chosen by marker-assisted parent selection, and a specific set of seedlings was selected by marker-assisted seedling selection, to validate the predictive power of this marker. The two groups of seedlings, further phenotyped for fruit texture, showed a clear difference in texture behaviour. The selection of this marker also showed a higher efficiency than Md-ACS1 and Md-ACO1, two functional markers currently implemented in different breeding programs. Finally, the allelic effect was estimated by computing the breeding values in a collection of 83 different apple cultivars. The results reported here confirmed the association of Md-PG1SSR10kd with texture sub-traits, proposing this as a novel promising selection strategy suitable for apple fruit texture.

Mature apples of ‘Fuji’ and ‘Fuji’ sports sourced from around the world were found to possess clumps of multicellular, branched callus hairs in the outer 17 mm of the outer cortex. The clumps of callus hairs were particularly well developed in samples of ‘Fuji Suprema’ from Brazil, moderately developed in ‘Fuji KIKU’ from Italy and in ‘Fuji’ from South Africa, Chile, New Zealand and the USA, and were consistently least developed in ‘Fuji’ from China. These previously unreported callus hairs grow in the intercellular air spaces between the parenchyma cells and also in larger air lacunae in the apple flesh. In both of these locations they have the potential to reduce the efficiency of gas exchange into and out of the fruit during storage. Initial observations suggest that the callus hairs within a clump do not continue to develop after harvest. In ripe apples, the cells of the callus hairs contain chlorophyll and starch and under UV light the contents of the vacuoles autofluoresce an intense blue colour. The outer surface of each callus hair cell is covered with characteristic globular protuberances which attach the hairs to each other and to the surrounding parenchyma. After a period of storage, many of the clumps of callus hairs remain packed with starch granules even though starch has been metabolised from the surrounding parenchyma.

The evaluation and improvement of global education has been a priority, but the complexity of the factors that surround and affect educational practice, especially in developing countries, such as Colombia make to achieve this is goal a challenge. The traditional method of assessing and improving teaching practices has been based on a qualitative assessment of teachers and students, in long time intervals. Additionally, these evaluations are not available in order to identify weaknesses of teaching practices and thus correct on time. For these reasons, in this paper the concept of SmartRoom, which is a type of learning environment that looks for improving teaching practices through the evaluation of a set of teaching practice performance metrics, and thus suggest the educator a change in the methodology or type of presentation of the contents that are better suited to the conditions of the current class classroom, is proposed. Besides, the development of an inference system, which using the body postures of students within the classroom determine their engagement or attention levels, is described. As far as we know no one has done studies associating the issue of describing the quality of teaching practices with intelligent learning environments (Smart Classroom).

In apple breeding fruit quality is a crucial aspect to guarantee commercial success of new varieties. Among the several quality attributes, individual sugars and acid components, as well as texture, are considered important features due to their significant contribution to sensory quality and consumer's acceptance. In traditional breeding, however, selection for these particular traits is a time consuming process, due to the long unproductive juvenile phase of apple seedlings. This step can be assisted to date by the use of molecular markers, an important diagnostic tool useful to anticipate and assist the identification of novel apple varieties characterized by superior fruit quality behaviour. However, the routinely implementation of molecular markers in breeding programs is still limited. In this study a new approach named Pedigree Based Analysis will be used on six full-sib progenies and their pedigree (composed by 15 varieties, represented by founders and ancestors), to target the main set of quantitative trait loci (QTLs). This strategy will allow the identification of the most valuable alleles present in the breeding activities of both Italian institutes. The ultimate goal of the Laimburg - FEM joint project is the identification and validation of molecular markers as a suitable tool for Marker Assisted Breeding in the two on-going apple breeding programs.

Shelf life determines the economic life time of mature apples, which can be either freshly harvested or stored. Good shelf life is highly associated with a slow decrease of fruit firmness at room temperature. Apple is a climacteric fruit, in which loss of firmness seems to be physiologically related to ethylene. Ethylenes biosynthetic pathway is controlled by two large gene families coding for 1-aminocyclopropane-1-carboxylate synthase (ACS) and 1-aminocyclopropane-1-carboxylate oxydase (ACO). In this study, one ACS and one ACO gene were examined for their effect on ethylene production and shelf life in apple using gene specific molecular marker, and have also been positioned on a molecular marker linkage map. The ACO marker was developed in this research and mapped on linkage group (LG) 10 of the crosses Prima × Fiesta and Fuji × Mondial Gala, within the 5% border of a previously identified fruit firmness QTL [Theor Appl Genet 100 (2000) 1074]. We denoted this locus as Md-ACO1. In addition, we mapped the previously developed Md-ACS1 marker [Theor Appl Genet 101 (2000) 742] on LG15. Studies on the cross Fuji × Braeburn revealed that Md-ACS1 and Md-ACO1 independently affect the internal ethylene concentration (IEC) as well as shelf life of apple, Md-ACS1 having the strongest effect. Descendants homozygous for Md-ACS1-2 and Md-ACO1-1 showed to have the lowest ethylene production as well as superior shelf-life. These two genes are candidates to be included in marker assisted breeding

Volatile organic compounds (VOCs) are chemical species that play an important role in determining the characteristic aroma and flavor of fruits. Apple (Malus × domestica Borkh.) cultivars differ in their aroma and composition of VOCs. To determine varietal differences in the aroma profiles, VOCs emitted by 7 modern and 35 old apple cultivars were analyzed using Proton Transfer Reaction Mass Spectrometry (PTR-MS). PTR-MS is a rapid, reproducible, and non-destructive spectrometric technique for VOC analysis of single fruits, developed for direct injection analysis. In the present study, we analyzed the differences in the emission of VOCs from single fruits at harvest and after a storage period of 60±10 days, followed by 3 d of shelf life. Our results show that VOC profile differences among apple cultivars were more pronounced after storage than at harvest. Furthermore, chemodiversity was higher in old cultivars compared to modern cultivars, probably due to their greater genetic variability. Our data highlight the importance of storage and shelf life are crucial for the development of the typical aroma and flavor of several apple cultivars. The validity of the method is demonstrated by comparison of two different harvest years.

International audience; Key message: Proof of concept of Bayesian integrated QTL analyses across pedigree-related families from breeding programs of an outbreeding species. Results include QTL confidence intervals, individuals' genotype probabilities and genomic breeding values. Abstract: Bayesian QTL linkage mapping approaches offer the flexibility to study multiple full sib families with known pedigrees simultaneously. Such a joint analysis increases the probability of detecting these quantitative trait loci (QTL) and provide insight of the magnitude of QTL across different genetic backgrounds. Here, we present an improved Bayesian multi-QTL pedigree-based approach on an outcrossing species using progenies with different (complex) genetic relationships. Different modeling assumptions were studied in the QTL analyses, i.e., the a priori expected number of QTL varied and polygenic effects were considered. The inferences include number of QTL, additive QTL effect sizes and supporting credible intervals, posterior probabilities of QTL genotypes for all individuals in the dataset, and QTL-based as well as genome-wide breeding values. All these features have been implemented in the FlexQTL (TM) software. We analyzed fruit firmness in a large apple dataset that comprised 1,347 individuals forming 27 full sib families and their known ancestral pedigrees, with genotypes for 87 SSR markers on 17 chromosomes. We report strong or positive evidence for 14 QTL for fruit firmness on eight chromosomes, validating our approach as several of these QTL were reported previously, though dispersed over a series of studies based on single mapping populations. Interpretation of linked QTL was possible via individuals' QTL genotypes. The correlation between the genomic breeding values and phenotypes was on average 90 %, but varied with the number of detected QTL in a family. The detailed posterior knowledge on QTL of potential parents is critical for the efficiency of marker-assisted breeding.

Texture is a principal quality factor and represents one of the main priorities in apple postharvest management and breeding programs designed for the creation of new ideotypes defined by a better fruit quality and extended storability. The apple panorama is characterized by a great variability of texture performance due to specific functional regulation and genetic control of the physiological machinery devoted to the degradation of the polysaccharide architecture of the middle lamella/cell wall structure. In this work we present an investigation of texture dynamics in apple, in terms of variation of several texture components dissected over two months of postharvest storage. Apple texture was assessed at harvest and after storage, by acquiring both mechanical and acoustic profiles in a collection of 83 apple cultivars. The general texture variability, illustrated over the reduced hyperspace defined by principal components, revealed a different variety distribution between the two stages. Time evolution plots and the novel storage index presented here highlighted that each single texture component behaves differently, as seen by some cultivars (i.e. ‘Fuji’) having a more favourable acoustic response after postharvest. The dissected fruit texture dynamics assessed in a set of reference apple cultivars are discussed.

Texture of apple fruit originates from anatomic traits related to cell wall architecture and is one of its most important quality characteristics, thus there is the desire to better understand the different factors which contribute to apple texture. Here we present a novel approach based on the simultaneous profiling of the mechanical and acoustic response of the flesh tissue to compression, using a texture analyzer coupled with an acoustic device. The methodology was applied to a 86 different apple cultivars, measured after two months postharvest cold storage and characterised by 16 acoustic and mechanical parameters. Statistical treatment of the data with principal component analysis (PCA) allowed for the identification of three groups of variables, the mechanical ones being clearly distinguished from the acoustic ones. Moreover, the distribution of the apple cultivars in the multivariate PCA plot allowed characterisation of the cultivars according to their textural performance. Each cultivar was analyzed also with non-destructive vis/NIR spectroscopy in order to determine impartially the ripening stage. Sensory evaluation by panellists was performed on a selected group of cultivars and sensory data correlated with the acoustic-mechanical data. The results demonstrate the good performance of our combined acoustic-mechanical strategy in measuring apple crispness as it is perceived by human senses.

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Genetic parameters for apple (Malus x domestica) fruit external traits (fruit size, ground colour, proportion of over colour and attractiveness) and sensory traits (firmness, crispness, texture, juiciness, flavour, sugar, acidity and global taste) were estimated using 2,207 pedigreed genotypes from breeding programmes in six European countries. Data were scored for 3 years and four periods during storage. Analyses were performed with a restricted maximum likelihood method using VCE 5.1.2 software. Heritability estimates ranged from medium to high for instrumental traits. Genetic correlations between firmness and sugar were medium and low between firmness and acidity. Sensory traits showed low to high heritability, acidity and flavour being, respectively, the most and the less heritable. Global taste was strongly correlated with texture, juiciness, and flavour and relatively less correlated with crispness and acidity. Sensory sugar and acidity showed highly negative correlations whereas their instrumental measurements showed low and increasing positive correlations from harvest to 4 months post-harvest. Sugar exhibited a higher sensory/instrumental divergence. Conversely, instrumental and sensory firmness were highly correlated. Fruit external characteristics had medium heritability. Fruit attractiveness had highest and lowest correlations with fruit size and ground colour, respectively. Best linear unbiased predictors of breeding values were computed for all genotypes with the software PEST. The results were analysed with regard to the dynamic and the reliability of genetic parameters according to the scoring dates. Original issues of the study and the importance of the obtained results for efficient designs of further apple fruit quality breeding programmes were discussed

Candidate genes involved in ethylene production during ripening

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