Apple Cultivars Research Articles

Seasonal Abundance of Aphids on Apple Cultivars and Their Chemical Control

Seasonal Abundance of Aphids on Apple Cultivars and Their Chemical Control

Pathogenicity evaluation of Cytospora species in 13 apple (Malus domestica) varieties and wild apple (Malus sieversii) in Xinjiang, China

AbstractApples are a popular fruit worldwide and are cultivated in the Xinjiang Uygur Autonomous Region (XUAR) in China. Cytospora canker disease is a serious problem in the apple industry in China. Pathogenicity of all historically recorded Cytospora species from Malus hosts was tested on the leaves and breaches of 13 varieties of apple (Malus domestica) and wild apple (Malus sieversii). Cytospora leucosperma and Cytospora pruinopsis were the most aggressive pathogens on apple and wild apple trees in Xinjiang. Meanwhile, Cytospora leucostoma, Cytospora nivea and Cytospora parakantschavelii were the least aggressive. In addition, Fuji and Golden Delicious were the most Cytospora canker disease‐resistant apple varieties and are recommended for future promotion. However, Sitagan and Erzizi were readily infected by Cytospora. Our findings provide a theoretical basis for field disease epidemic monitoring and tailoring disease prevention and control strategies based on the disease resistance of the variety and the aggressiveness of the pathogen.

Combined effect of timing, position and management on Halyomorpha halys feeding injury assessment on apple cultivars

AbstractHalyomorpha halys is an invasive stink bug, native to east Asia, responsible for extensive economic loss in numerous crops. Since several factors can influence the severity of the recorded injury level, we performed field and semi‐field experiments in commercial apple orchards to monitor their interaction. To establish how position (both in the orchard and on the canopy), management and cultivar interact in determining pre‐harvest injury levels, more than 100,000 apples, distributed over 106 orchard blocks, were examined in the field. Apples located higher in the canopy, on edge rows and in orchards with organic management had a higher number of external injuries and such factors were more relevant when occurring in combination, and on mid and late‐season cultivars. Exclusion cages were used to assess if the injury severity changed with the apple growth stage and with the life stage of H. halys, exposing Red delicious apples to adults and nymphs for 48 hours, from May to July. Early‐season injuries did not evolve in distinct depressions nor in wide areas with necrotic tissue. Later in season, the injury severity was higher and similar for adults and older nymphs (fourth and fifth instars), with the development of depressions externally and necrotic tissue internally. Thus, even a low number of individuals could cause severe damage, over a short exposure period, when it happened near full maturation. The combined results offer new insights to support the development of informed and sustainable control strategies.

Description of the Introduced variety of apple (Malus domestica Borch) "Challenger"

Description of the Introduced variety of apple (Malus domestica Borch) "Challenger"

Assessment of apple soluble sugar content by hyperspectral vegetation indexes

Soluble sugar content in apple fruit is a crucial internal quality factor. Rapid and accurate estimation of soluble sugar content in apple fruit is helpful to predicting maturity. However, few studies have used an approach of hyperspectral vegetation indexes for monitoring apple soluble sugar content from ground-based handheld hyperspectral data. This study systematically analyzed the performance of hyperspectral vegetation indexes of apple in estimating the soluble sugar content. The visible and near infrared spectral of apple samples were measured by using a hyperspectral equipment, with the wavelength of 350–2500 nm. Eleven early-ripening apple varieties were collected from orchards located in five provinces of China, and the sugar content of each apple fruit sample was measured using laboratory methods. Two-band combination method was used to identify the effective spectral index. Results showed that the newly developed two-band ratio spectral index R833/R834 (Rλ is the reflectance value at wavelength λ) was recommended as the optimal index for monitoring early-ripening apple soluble sugar content, generated the coefficients of determination, root mean square error (RMSE) and residual prediction deviation (RPD) values between the measured and predicted values of 0.73%, 0.72%, and 1.38%, respectively. Result indicated that the newly developed two-band index R833/R834 can be used to nondestructively determine apple fruit soluble sugar content. The findings can provide insight into the relationship between the optical properties of apple fruit at different wavelengths and soluble sugar content.

Prevalence and Management of Post-harvest Rots of Apple in Himachal Pradesh

During a survey of post-harvest diseases of apple in Himachal Pradesh conducted during July to September 2021, fourteen different types of rots were observed. Among these, Penicillium expansum (blue mould) was most destructive with exclusive incidence of 43.8%. Surveys of different markets/stores of Himachal Pradesh revealed that the total losses due to apple decay at various locations varied from 7.80 to 21.93%. Ten important commercial varieties of apple were screened for their comparative susceptibility against fruit decay.Tydeman’s Early Worcester was found to be most tolerant to all the rot causing fungi with mean per cent rotting of 23.26%.Cow urine was found most effective in providing 79.21% growth inhibition of test fungi under study. The next best bio-products were Emblica officinalis (amla), Melia azadirach (darek) and Dodonaea viscose (mehandu) with per cent growth inhibition of 75.66, 73.59 and 68.48%, respectively. Under in vitro conditions, mancozeb (0.1%) was the most effective fungicide providing 84.83% growth inhibition. The efficacy of mancozeb as dip treatment at 0.1% concentration was judged to be significantly superior followed by 0.05% carbendazim with per cent control of 95.97 and 92.35%, respectively. Preharvest spray of mancozeb (0.3%) was highly effective in checking all the test fungi under different type of storage for 2 months. 1-methyl cyclopropene (MCP) fumigation of apple fruits immediately after harvesting for 12 hours was most effective in checking the test fungi under study providing 89.60% control.

ВЛИЯНИЕ ЯБЛОЧНОГО ЖМЫХА В КОРМАХ НА ОБЩИЙ ГОМЕОСТАЗ ОРГАНИЗМА ПЕРЕПЕЛОВ

Apple pomace is a valuable raw material containing a sufficient amount of dietary fiber, minerals and biologically active substances. This paper describes the results of an experiment to study the effect of apple pomace added to feed on the general blood parameters of Texas breed quails. The experiment lasted 21 days in the veterinary clinic of the Saratov State University of Genetics, Biotechnology and Engineering named after N.I. Vavilov, according to the principle of analogues, three experimental groups were created, ten heads in each group, with different amounts of pomace in the feed, as a percentage: group 1 - 8 %, group 2 - 10 %, group 3 - 15 %. A control group was also formed, receiving a diet without pomace. The diet of the experimental groups consisted of complete granulated food for quails, to which was added apple pomace from a local manufacturer - ACSSC «Khvalynsky Sad». The apple pomace was obtained from the Berkutovskoye apple variety and dried using a Russian convective dryer Ezidri Ultra FD1000 Digital. A blood test was done before the start of the experiment and after, at the Veterinary Hospital Scientific Research Center on a PCE-90Vet hematology analyzer. According to the results of the experiment it was established that the best indicators of homeostasis in the body of quails were in the second experimental group, which was supplemented with 10 % apple pomace.

Classification of Apple Color and Deformity Using Machine Vision Combined with CNN

Accurately classifying the quality of apples is crucial for maximizing their commercial value. Deep learning techniques are being widely adopted for apple quality classification tasks, achieving impressive results. While existing research excels at classifying apple variety, size, shape, and defects, color and deformity analysis remain an under-explored area. Therefore, this study investigates the feasibility of utilizing convolutional neural networks (CNN) to classify the color and deformity of apples based on machine vision technology. Firstly, a custom-assembled machine vision system was constructed for collecting apple images. Then, image processing was performed to extract the largest fruit diameter from the 45 images taken for each apple, establishing an image dataset. Three classic CNN models (AlexNet, GoogLeNet, and VGG16) were employed with parameter optimization for a three-category classification task (non-deformed slice–red apple, non-deformed stripe–red apple, and deformed apple) based on apple features. VGG16 achieved the best results with an accuracy of 92.29%. AlexNet and GoogLeNet achieved 91.66% and 88.96% accuracy, respectively. Ablation experiments were performed on the VGG16 model, which found that each convolutional block contributed to the classification task. Finally, prediction using VGG16 was conducted with 150 apples and the prediction accuracy was 90.50%, which was comparable to or better than other existing models. This study provides insights into apple classification based on color and deformity using deep learning methods.

Molecular and chemical evaluation of patulin production of Aspergillus and Penicillium-like species isolated from Hungarian apples

Mycotoxins are secondary fungal metabolites harmful to humans and animals. Patulin (PAT) is a toxin found in different food products but especially in apples and their derivative products. The most common fungi producers of this compound are Aspergillus clavatus and Penicillium expansum. The production of patulin, as other mycotoxins, can be impacted by diverse phenomena such as water and nutrient availability, UV exposure, and the presence of antagonistic organisms. Consequently, gaining a comprehensive understanding of climate and environmental conditions is a crucial step in combating patulin contamination. In this study, moulds were isolated from 40 apple samples collected from seven locations across Hungary: Csenger, Damak, Pallag, Lövőpetri, Nagykálló, and Újfehértó. A total of 183 moulds were morphologically identified, with 67 isolates belonging to the Alternaria, 45 to the Aspergillus, and 13 to the Penicillium groups. The location possessed a higher influence than farming method on the distribution of mould genera. Despite the requirement of higher temperature, Aspergillus species dominated only for the region of Újfehértó with approximately 50% of the isolates belonging to the genus. Four of the seven locations assessed: Csenger, Debrecen-Pallag, Nyírtass and Nagykálló, were dominated by Alternaria species. All isolates belonging to the genera Aspergillus and Penicillium were tested for the presence of the isoepoxidone dehydrogenase (idh) gene, a key player in the patulin metabolic pathway. To guarantee patulin production, this ability was confirmed with TLC assays. The only Aspergillus strain that presented a positive result was the strain Aspergillus clavatus B9/6, originated from the apple cultivar Golden Reinders grown in Debrecen-Pallag by integrated farming. Of the Penicillium isolates only one strain, B10/6, presented a band of the right size (500-600 bp) for the idh gene. Further sequencing of the ITS gene showed that this strain should be classified as Talaromyces pinophilus. The TLC tests confirmed this microorganism as the only patulin producer under the studied conditions for its cluster.

Chemical Characteristics of Exotic Apple Cultivars in Kashmir's Temperate Conditions: Impact of Diverse Pollen Sources

Chemical Characteristics of Exotic Apple Cultivars in Kashmir's Temperate Conditions: Impact of Diverse Pollen Sources

Effect of Storage Conditions on the Volatilome, Biochemical Composition and Quality of Golden Delicious and Red Delicious Apple (Malus domestica) Varieties.

The effects of normal (NA) and controlled atmosphere (CA) storage and postharvest treatment with 1-methylcyclopropene (1-MCP) before CA storage for 5 months on the volatilome, biochemical composition and quality of 'Golden Delicious' (GD) and 'Red Delicious' (RD) apples were studied. Apples stored under NA and CA maintained and 1-MCP treatment increased firmness in both cultivars. NA storage resulted in a decrease of glucose, sucrose and fructose levels in both cultivars. When compared to CA storage, 1-MCP treatment caused a more significant decrease in sucrose levels and an increase in glucose levels. Additionally, 1-MCP-treated apples exhibited a significant decrease in malic acid content for both cultivars. All storage conditions led to significant changes in the abundance and composition of the volatilome in both cultivars. GD and RD apples responded differently to 1-MCP treatment compared to CA storage; higher abundance of hexanoate esters and (E,E)-α-farnesene was observed in RD apples treated with 1-MCP. While 1-MCP was effective in reducing (E,E)-α-farnesene abundance in GD apples, its impact on RD apples was more limited. However, for both cultivars, all storage conditions resulted in lower levels of 2-methylbutyl acetate, butyl acetate and hexyl acetate. The effectiveness of 1-MCP is cultivar dependent, with GD showing better results than RD.

Movement of ACC oxidase 3 mRNA from seeds to flesh promotes fruit ripening in apple

Xenia, the phenomenon in which the pollen genotype directly affects the phenotypic characteristics of maternal tissues (i.e., fruit ripening), has applications in crop production and breeding. However, the underlying molecular mechanism has yet to be elucidated. Here, we investigated whether mobile mRNAs from the pollen affect the ripening and quality-related characteristics of the fruit using cross-pollination between distinct Malus domestica (apple) cultivars. We demonstrated that hundreds of mobile mRNAs originating from the seeds are delivered to the fruit. We found that the movement of one of these mRNAs, ACC oxidase 3 (MdACO3), is coordinated with fruit ripening. Salicylic acid treatment, which can cause plasmodesmal closure, blocks MdACO3 movement, indicating that MdACO3 transcripts may move through the plasmodesmata. To assess the role of mobile MdACO3 transcripts in apple fruit, we created MdACO3-GFP-expressing apple seeds using MdACO3-GFP-overexpressing pollen for pollination and showed that MdACO3 transcripts in the transgenic seeds move to the flesh, where they promote fruit ripening. Furthermore, we demonstrated that MdACO3 can be transported from the seeds to fruit in the fleshy-fruited species tomato and strawberry. These results underscore the potential of mobile mRNAs from seeds to influence fruit characteristics, providing an explanation for the xenia phenomenon. Notably, our findings highlight the feasibility of leveraging diverse pollen genomic resources, without resorting to genome editing, to improve fruit quality.

Development of technology for manufacturing apple chips based on the results of assessment of technological and consumer properties of raw apples

Modern trends in people's nutrition are determined primarily by changed living conditions, in which the desire to reduce the time spent on solving everyday issues, including cooking, has led to the creation of a new range of food products, among which fruit snacks are especially distinguished. In non-CIS countries, apple chips are the most popular and have become in demand among consumers of almost all age categories. Apple chips from imported manufacturers have already appeared on shelves in Kazakhstan, which has presented domestic scientists with the urgent task of establishing their own production from apples growing in our country, since the raw material base of the southern regions can already provide industrial-scale production of various varieties of apples. Apple chips differ from traditional dried fruits in their organoleptic characteristics - their taste is richer, retaining the shape of the plates and crispy crust, and the vitamin and microelement composition is close to the composition of fresh apples. The goal of our research is to develop a technology for the production of apple chips from apple varieties grown on an industrial scale by farms in the Turkestan region using technological methods of blanching sliced apple slices with a special solution and convection drying them. As a research methodology, experimental research methods were used, including the selection of initial apple raw materials, the composition of the blanched solution, the regime parameters for processing apple plates in solution and their drying, and the use of expert methods for determining the consumer characteristics of finished apple chips. The article presents the results of research on the development of technology for the production of apple chips based on an assessment of the technological and consumer characteristics of the Jonagold, Golden, Granny, and Jeramin apple varieties. It has been established that to process them into apple chips it is necessary to select varieties of winter and late winter ripening. The selected ingredient composition of the blanched solution is 30 wt. % sucrose, 1.5 wt. % ascorbic acid, 0.5 wt. % citric acid. The cutting thickness of apple slices should be in the range of 1.5-2.5 mm. Regime parameters for processing apple plates in solution: t = 45-50 0C, processing time 3-5 minutes. The drying parameters for blanched apple plates have been set: t=100-110 0C, drying time 12-14 hours. The moisture content of the finished apple chips was 15%.

Genetic diversity and geographic distribution patterns of Malus landraces from 5 cultivated species under climate change in China

China is the largest center of genetic diversity of apple (Malus Mill.), with rich germplasm resources. In the process of evolution and domestication, a large number of apple landraces appeared, and they played a very important role before the introduction of modern cultivated apple varieties to China. However, the habitat of Malus landraces is under serious threat. In this study, 19 pairs of polymorphic simple sequence repeat primers were used to analyze the genetic structure and genetic relationships of Malus landraces and the potential distribution was predicted according to eight environmental variables using MaxEnt modeling. The results showed that the genetic variation of Malus landraces was high (Ho = 0.728 and He = 0.884), and the genetic differentiation was mainly distributed within respective populations and with almost no differentiation among populations. The five population groups were ranked, from highest genetic diversity level to lowest, as follows: Malus domestica subsp. chinensis > Malus prunifolia > Malus robusta > Malus asiatica > Malus micromalus. The 216 germplasms were divided into five groups based on Nei's genetic distance, whereas the Bayesian structure analysis categorized them into two groups. Population structure and principal coordinate analyses showed that Malus domestica subsp. chinensis, Malus asiatica and Malus prunifolia may be derived from similar genetic sources. In the modeling analysis, the cumulative contribution of temperature to the distribution of Malus landraces in suitable growth areas reached 66.1 %, and BIO4 (temperature seasonality) was identified as the major factor influencing the distribution of Malus landraces. Under four future emission scenarios, the potential distribution range of Malus landraces basically unchanged, but the total potential distribution area is projected to grow greatly over time and will tend to shift to higher latitudes.

Influence of Polyphenols on the Resistance of Traditional and Conventional Apple Varieties to Infection by Penicillium expansum during Cold Storage

This study investigates the impact of polyphenols on the susceptibility of traditional and conventional apple varieties to Penicillium expansum infection and subsequent patulin biosynthesis during cold storage. Traditional varieties, notably ‘Bobovec’, exhibit significantly higher levels of total polyphenols (650.56 ± 9.85 mg/L) and flavonoids (184.11 ± 1.48 g/kg dw) compared to conventional ones after six months of storage, accompanied by the identification of key polyphenols such as chlorogenic acid, epicatechin, phloridzin, quercetin and procyanidins B1 and B2. These traditional varieties demonstrate enhanced resistance to P. expansum infection, as evidenced by prolonged periods for colony formation, particularly ‘Bobovec’ with an average of 384 h. Furthermore, the traditional variety ‘Winter Banane’ and conventional varieties ‘Idared’ and ‘Fuji’ showed increased patulin biosynthesis postinoculation, indicating higher susceptibility to fungal infection. The findings underscore the potential of polyphenols from traditional apple varieties as natural defences against fungal infections, suggesting the importance of selecting or breeding varieties with higher polyphenol content to improve resistance to postharvest pathogens, thereby enhancing the quality and safety of stored apples.

SNP genotyping Dutch heritage apple cultivars allows for germplasm characterization, curation, and pedigree reconstruction using genotypic data from multiple collection sites across the world

The curation and preservation of Dutch apple germplasm depends on reliable accession level information. However, many accessions of Dutch heirloom apple cultivars maintained publicly by the “Centre for Genetic Resources, the Netherlands” (CGN) and privately by Dutch pomological societies lack information regarding true-to-typeness and pedigree ancestry. The aim of this study was to address this knowledge gap by genotyping 652 apple accessions maintained in the CGN collection and Dutch private collections, compare their genotypic information to each other and to a large database of apple cultivars from around the world to identify genotypic duplicates and pedigree relationships for the Dutch apple cultivars. Towards this aim, accessions were genotyped on the 20 K Illumina Infinium(R) apple SNP array and with 15 SSR markers. Each accession was assigned to a genotypic profile code (MUNQ codes, as used in previous studies) facilitating communication regarding genotypic duplicates. There were 211 (51.1%) genotypic profiles in the Dutch germplasm which were not identified in other germplasm collections. Private collections maintained many of these unique accessions, including important pedigree ancestors. The study identified a number of common pedigree ancestors of Dutch cultivars, such as ‘Herfst Bloem Soete’, ‘Huismanszoet’ (2), and ‘Reinette Rouge Étoilée’. The duplicate and pedigree reconstruction results and relevant literature descriptions were used to pomologically verify the identity of relevant accessions. The results of this study resolved identity disputes, helped to decide which accessions should be retained or included in the CGN collection, and benefited ongoing pomological studies in ancestry and provenance of traditional Dutch cultivars.

Effect of Foliar Sprays of Phenylalanine, Nano-potash and Potassium Sulphate on Fruit Quality Attributes of Apple (Malus x domestica Borkh) cv. Ambri

The present investigation was carried out at Experimental field of Ambri Apple Research Centre (AARC), Shopian, SKUAST-Kashmir, during the year 2022-2023. Eight treatments, viz; control (water spray), potassium sulphate (5 g per litre of water), phenylalanine (@ 0.1, 0.2 and 0.3%), nano-potash (@ 1, 2 and 3ml/l of water) were selected for colour improvement. The treatments were applied 30 days prior to harvest. The experiment was laid in complete randomised block design with 3 replications having 3 trees per replication. The results showed that all the treatments outperformed control in terms of chemical characteristics. The treatment T4 (Phenylalanine @ 0.3%) significantly excelled in all the treatments applied. Significantly higher anthocyanin content (14.41 mg/100g), antioxidants (75.71 %), total sugars (12.98 %), TSS (16.23 %), fruit chlorophyll (0.59 mg/g fw) and fruit ascorbic acid (23.93 %) was recorded in T4 (Phenylalanine @ 0.3%) as compared to other treatments. According to the current study, apple cultivar Ambri responded favourably to the application of foliar phenylalanine in improving chemical traits, which otherwise lacks in this cultivar. The application of Phe @ 0.3% , 30 days prior to harvest proved superior in enhancing the quality attributes, notably the anthocyanin content of apple cv. Ambri.

Excluding sunscald from long-term storage of ‘Granny Smith’ apples

Sunscald is a postharvest apple and pear peel disorder primarily caused by excessive light exposure during the growing season. Symptoms are not apparent at-harvest but develop during storage as superficial brown or gray discolored patches on the exposed portion of the apple. A novel protocol using hyperspectral imaging (HSI) was developed to identify apples at- harvest that are more likely to develop the disorder and reduce sunscald in the cold chain by eliminating at-risk apples from long-term storage. PLS-DA and LOGISTIC models and an index summarizing the chlorophyll to carotenoid ratio were tested for this purpose using two populations selected for different sun exposure levels and four populations harvested from whole trees. The accuracy of models varied seasonally. However, detection of sunburn and estimation of sunscald risk based on index values was a more consistent approach. Summarizing peel area according to this index was the basis for categorizing whole apples as rejected (sunburned), high (sunscald) risk, or low-risk. Categorization segregated apples nearly entirely into these categories with only an insignificant frequency of misclassification. The frequency of high-risk apples without sunburn symptoms in the populations harvested from whole trees fell below 20 %, although actual sunscald incidence within this category ranged from 55 % to 81 % among populations harvested from whole trees, highlighting that other factors beyond elevated sun exposure contribute to sunscald incidence. The classification model for low and high-risk categories had an accuracy of 83–93 % in four independent populations, with 99.9 % sensitivity to classify non-sunscalded fruit into the low-risk category. Sorting by sunburn presence and sunscald risk allows for apples that have sunburn symptoms to be excluded and those that are marketable but most likely to develop sunscald to be pushed to market rather than storage. With the appropriate source/sensor array, this approach is readily adaptable to sorting lines or even robotic harvesters. Challenges include adapting this approach for other apple and pear cultivars and extending capabilities for additional uses, including sorting fruit into additional categories representative of relative sunlight exposure.

Metabolomics comparison of four varieties apple with different browning characters in response to pretreatment during pulp processing

Browning commonly appeared in apple processing, which varied in different apple varieties. Present work investigated the metabolomics of four varieties apple of Yataka, Gala, Sansa, and Fuji, which possessed different browning characteristics and related enzymes. Sansa as browning insensitive apple variety, exhibited the least chroma change with the lowest PPO activity and the highest SOD activity among the four apple varieties. Browning inhibition pretreatment increased the activity of SOD and PAL and decreased PPO and POD activity. In addition, metabolomic variances among the four apple varieties (FC), their browning pulp (BR) and browning inhibition pulp (CM) were compared. And the key metabolites were in-depth analyzed to match the relevant KEGG pathways and speculated metabolic networks. There were 487, 644, and 494 significant differential metabolites detected in FC, BR and CM, which were consisted of lipids, benzenoids, phenylpropanoids, organheterocyclic compounds, organic acids, nucleosides, accounting for 23 %, 11 %, 15 %, 16 %, 11 % of the total metabolites. The differential metabolites were matched with 39, 49, and 36 KEGG pathways in FC, BR, and CM, respectively, in which other secondary metabolites biosynthesis metabolism was the most significant in FC, lipid metabolism was the most significant in BR and CM, and energy metabolism was markedly annotated in CM. Notably, Sansa displayed the highest number of differential metabolites in both its BR (484) and CM (342). The BR of Sansa was characterized by flavonoid biosynthesis, while the other three apple varieties were associated with α-linolenic acid metabolism. Furthermore, in browning sensitive apple varieties, the flavonoid and phenylpropanoid biosynthesis pathway was significantly activated by browning inhibition pretreatment. Phenolic compounds, lipids, sugars, organic acids, nucleotides, and adenosine were regulated differently in the four apple varieties, potentially serving as key regulatory sites. Overall, this work provides novel insight for browning prevention in different apple varieties.

Why we thrive beneath a northern sky – genomic signals of selection in apple for adaptation to northern Sweden

Good understanding of the genomic regions underlying adaptation of apple to boreal climates is needed to facilitate efficient breeding of locally adapted apple cultivars. Proper infrastructure for phenotyping and evaluation is essential for identification of traits responsible for adaptation, and dissection of their genetic composition. However, such infrastructure is costly and currently not available for the boreal zone of northern Sweden. Therefore, we used historical pomological data on climate adaptation of 59 apple cultivars and whole genome sequencing to identify genomic regions that have undergone historical selection among apple cultivars recommended for cultivation in northern Sweden. We found the apple collection to be composed of two ancestral groups that are largely concordant with the grouping into ‘hardy’ and ‘not hardy’ cultivars based on the pomological literature. Using a number of genome-wide scans for signals of selection, we obtained strong evidence of positive selection at a genomic region around 29 MbHFTH1 of chromosome 1 among apple cultivars in the ‘hardy’ group. Using phased genotypic data from the 20 K apple Infinium® SNP array, we identified haplotypes associated with the two cultivar groups and traced transmission of these haplotypes through the pedigrees of some apple cultivars. This demonstrates that historical data from pomological literature can be analyzed by population genomic approaches as a step towards revealing the genomic control of a key property for a horticultural niche market. Such knowledge is needed to facilitate efficient breeding strategies for development of locally adapted apple cultivars in the future. The current study illustrates the response to a very strong selective pressure imposed on tree crops by climatic factors, and the importance of genetic research on this topic and feasibility of breeding efforts in the light of the ongoing climate change.