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The study considered the use of soil herbicides: Begin Turbo, KS; Dual Gold, KE; Euro-Lighting, VRK; Command, KE; Pivot, VK; Proponite, KE; Zenkor Ultra, KS and partially soil action: Demetra, KE, and Dialen Super, KS. We conducted a comparative assessment of the biological effectiveness of the studied herbicides against the main species of weeds present in the experimental plots, annual and perennial dicotyledonous, annual cereal weeds. The effect of soil herbicide treatments on the physiological state of plants of apple, pear, walnut, and black currant was studied. The effect of the use of the studied drugs on the yield of protected crops for three years was evaluated. The tests proved the applicability of soil herbicides in nursery, production gardens, as well as on seedlings with a closed root system. The tested products, despite the principle of their action - penetration into weeds through the soil, did not harm the protected crops, no negative effect on the growth of trees and shrubs was recorded. The study revealed no evidence that drugs had a negative impact on fruit and berry crop productivity. There are suggestions for improving the efficacy of using soil herbicides when planting fruit and berry crops. Resumo O estudo considerou o uso dos herbicidas de solo: Begin Turbo, KS; Dual Gold, KE; Euro-Lighting, VRK; Command, KE; Pivot, VK; Proponite, KE; Zenkor Ultra, KS e ação parcial do solo: Demetra, KE e Dialen Super, KS. Realizou-se uma avaliação comparativa da eficácia biológica dos herbicidas estudados contra as principais espécies de plantas daninhas presentes nas parcelas experimentais, dicotiledôneas anuais e perenes, plantas daninhas de cereais anuais. Estudou-se o efeito de tratamentos com herbicidas de solo sobre o estado fisiológico de plantas de macieira, pera, nogueira e groselha preta. Foi avaliado o efeito do uso das drogas estudadas na produtividade de cultivos protegidos por três anos. Os testes comprovaram a aplicabilidade de herbicidas de solo em viveiros, hortas de produção, bem como em mudas com sistema radicular fechado. Os produtos testados, apesar de seus princípios de ação - penetração em ervas daninhas através do solo, não prejudicou as culturas protegidas, não foi registrado nenhum efeito negativo no crescimento de árvores e arbustos. O estudo não revelou evidências de que as drogas tenham um impacto negativo na produtividade das frutas e bagas. Existem sugestões para melhorar a eficácia do uso de herbicidas de solo ao plantar frutas e bagas.

This study was conducted to determine the effects of Quince BA29 (BA29), Quince A (QA), and Quince C (MC) rootstocks on phenological and morphological characteristics of ‘Deveci’, ‘Santa Maria’, ‘Abate Fetel’, and ‘Williams’ pear cultivars in Bafra (Samsun) ecological conditions between 2020-2021 years. It has been determined that the effect of rootstocks and cultivars on phenological characteristics was significant. In the study, the earliest flowering and harvest were in ‘Abate Fetel’, the latest flowering was in ‘Williams’, and the latest harvest was in the ‘Deveci’ cultivar. The highest rootstock diameter, trunk diameter and tree height were in BA29 and the lowest in MC rootstock. The highest canopy volume was determined in the ‘Santa Maria’ cultivar and the lowest in the ‘Williams’ cultivar. The effect of rootstocks and cultivars on leaf area was significant and the highest leaf area was determined in ‘Santa Maria’/QA combination. Annual shoot length of the MC rootstock was lower than the other rootstocks. It is thought that it would be more appropriate to continue the research for a long time to determine the most suitable cultivar/rootstock combination as a result of the data obtained due to the young trees of the plants where the research was carried out., Bu çalışma, Bafra (Samsun) ekolojik koşullarında Quince BA29 (BA29), Quince A (QA) ve Quince C (MC) ayva klon anaçlarının ‘Deveci’, ‘Santa Maria’, ‘Abate Fetel’ ve ‘Williams’ armut çeşitlerinin fenolojik ve morfolojik özellikleri üzerine etkisini belirlemek amacıyla 2020-2021 yılları arasında yürütülmüştür. Çalışmada en erken çiçeklenme ve hasat ‘Abate Fetel’, en geç çiçeklenme ‘Williams’, en geç hasat ise ‘Deveci’ çeşidinde olmuştur. En yüksek anaç çapı, gövde çapı ve ağaç boyunun BA29 en düşük ise MC anacında olduğu belirlenmiştir. En yüksek taç hacmi ‘Santa Maria’ en düşük ise ‘Williams’ çeşitlerinde belirlenmiştir. Yaprak alanı üzerine anaçların ve çeşitlerin etkisi önemli olup en yüksek yaprak alanı ‘Santa Maria’/QA kombinasyonunda belirlenmiştir. MC anacının yıllık sürgün uzunluğunun diğer anaçlardan daha düşük olduğu belirlenmiştir. Araştırmadan elde edilen verilerin sonucunda en uygun çeşit/anaç kombinasyonunun belirlenmesi için araştırmanın uzun süre devam ettirilmesi gerektiği düşünülmektedir.

Watercore is a common physiological disorder in pear and is closely related to excessive accumulation of sorbitol and sucrose. Our previous research found the watercore incidence of ‘Akibae’ (Pyrus pyrifolia cv. Akibae) fruit significantly decreased after boron application (BA). Moreover, foliar spray of boric acid also significantly improved fruit quality. To uncover the mechanisms underlying pear fruit response to BA, a comprehensive transcriptome analysis was performed in this study. Transcriptome results revealed a total of 3146 up-regulated and 1145 down-regulated differently expressed genes (DEGs) between control and treated fruits of ‘Akibae’ pear, respectively. BA significantly induced expression of sorbitol metabolism and sucrose metabolism genes. Besides, BA also increased the expression of starch degradation, fatty acid synthesis, IAA (indole-3-acetic acid) degradation, GA (gibberellin acid) synthesis and inhibit the expression of ethylene synthesis genes. Overall, these findings suggested that BA alleviated ‘Akibae’ watercore occurrence and improve fruit quality by regulating the decrease of sorbitol and sucrose, increased of fatty acid and a balance of plant hormone. Our results provided further information for understanding the molecular mechanism of the effect of boron application on pear fruit.

The present study was carried out to determine the effect of quince rootstocks (BA29, QA and MC) on plant growth, fruit quality and yield of ‘Santa Maria’ pear cultivar in 2020 and 2021. In this study, significant differences were determined by all growth, yield and quality parameters except for trunk diameter (TD), trunk cross-sectional area (TCSA), canopy volume, fruit stalk thickness, acidity, total soluble solids (TSS) in terms of research years and rootstocks from analysis of variance. Tree height, annual shoot length, leaf area, fruit weight, fruit width, and fruit length was lower in the MC rootstock than in the others. In the case of research years, out of annual shoot growth in 2020, all other parameters were higher in 2021. Fruit stalk length, fruit stalk thickness and fruit firmness were higher on MC rootstock than BA29 and QA. There was an insignificant difference between rootstocks in terms of TSS. The highest L* was in QA and MC; chroma was in QA and hue angle was in BA29 rootstock. The number of fruit was the highest (139.01 pieces/tree) in BA29 in 2021 and the lowest in MC (11.97 pieces/tree) in 2020. The highest yield per tree (30.62 kg), yield per hectare (58484.2 kg), yield per trunk cross-sectional area (2.24 kg/cm2) and yield per canopy volume (71.21 kg/m3) were measured in QA in 2021. In conclusion, the yield efficiency of ‘Santa Maria’ pear cultivar under high density planting on QA was better than other combinations in 2021. Since the plants on which the research is carried out are still young, it may be recommended to continue the research for many years to determine the most suitable rootstock.

Aroma is an appreciated fruit property, and volatile flavor plays a key role in determining the perception and acceptability of fruit products by consumers. However, metabolite composition that contributes to the aroma in fruit quality is unclear. In this study, we detected 645 volatile organic compounds of ‘Panguxiang’ pear in total, including esters, alcohols, alkanes, acids, ketones, terpenes and aldehydes. In addition, the levels of sugars, organic acids and amino acids in ‘Panguxiang’ pear were investigated using high-performance liquid chromatography. In the aroma generation, glucose was the dominant sugar, followed by sucrose and fructose. At the development transferred storage stage, organic acids may not participate in aroma biosynthesis. The amino acids that may play potential roles in aroma substance synthesis are tyrosine and glycine. Through metabolomics analysis at different stages of ‘Panguxiang’ pear, we selected 65 key metabolites that were significantly related to glucose, sucrose, fructose, tyrosine and glycine, according to the trends of metabolite concentrations. Finally, we chose eight candidate metabolites (e.g., three esters, two aldehydes, one alcohol, one acid and one ketone) as the representative aroma substances of the ‘Panguxiang’ pear compared to the metabolome of the ‘Korla’ at stage Z5. Data and results from this study can help better understand the variations in aroma quality among pear varieties and assist in developing breeding programs for pear varieties.

This research was conducted to determine the influences of biopolymer dip-coating pretreatments as a non-thermal green technology on the drying behavior, retention of bioactive compounds, and quality properties of pears. The fresh pears were washed, peeled, and diced into cubes of 5 × 5 mm with a 2 mm thickness and were dipped into 0.3% (w/v) solutions of sodium alginate (SA), pectin (PC), xanthan gum (XG), Arabic gum (AG), and gelatin (GE) before hot air drying (70 °C, 2.0 m/s). The weight loss of samples during drying was recorded online, and the moisture ratio (MR) and drying rate were plotted against drying time. Biopolymers significantly decreased the drying time (maximum 33.33% by SA) compared with uncoated samples except for XG. Moisture diffusion coefficients were determined according to Fick’s second law of diffusion by plotting LnMR against drying time, and a linear regression analysis was applied to the data for the determination of moisture diffusion coefficients which ranged from 2.332 to 3.256 × 10−9 m2/s. The molecular transport of momentum, heat, and mass were determined from Newton’s law of viscosity, Fourier’s law, and Fick’s law, respectively. The results indicated that the friction drag force, convective heat, and mass transfer coefficients were 6.104 × 10−6 N, 76.55 W/m2·K, and 0.0636 m/s, respectively. Mathematical modeling showed the suitability of the Midilli and Kucuk and the Peleg models for the prediction of drying and rehydration processes, respectively. Thermal conductivity, specific heat, and density of coated samples ranged from 0.559–0.579 (W/m·K), 3735–3859 (J/kg·K), and 850.90–883.26 (Kg/m3), respectively. The porosity was reduced due to the penetration of biopolymers into the cellular matrix of samples. The highest total polyphenol content and antioxidant activity belonged to the AG samples. The biopolymers covering the surface of samples produced a protection layer against the loss of bioactive compounds. Biopolymers can be successfully used as a non-thermal green process for improving the drying and quality characteristics of pears at the industrial level.

CAMTA are calcium-modulating binding transcription factors that contribute to plant development. We identified 46 CAMTA genes from eight Rosaceae species and divided them into five subgroups based on a phylogenetic tree. Our analysis indicated that CAMTA is a highly conserved family among Rosaceae species, with a conserved DNA-binding domain (CG-1) and a conserved transcription factor immunoglobulin domain (TIG). Following a recent whole-genome duplication event, the genomes of Chinese white pear, European pear, and apple experienced significant expansion, resulting in the number of CAMTA genes being twice that of the other species. Cis-element identification showed that the distribution of the zein metabolism regulation-responsive element was different in the promoters of Chinese white pear (55.56%) and European pear (11.11%) CAMTA gene families. The gene expression results showed that PbrCAMTA1, 2, 6, 7 was highly expressed in pear fruit. Among them, PbrCAMTA2 may have a key influence on fruit softening, as observed in transient transformation experiments. In conclusion, our results provide crucial insights into the evolution of the CAMTA gene family in pear and other Rosaceae species and identify a candidate PbrCAMTA gene, which is involved in the dynamic development of pear fruits.

Watercore is a physiological disorder which often occurs in Rosaceae fruits, and it causes hypoxia stress, promoting fruit decay. γ-aminobutyric acid (GABA) was reported as being involved in different abiotic stresses, and glutamate decarboxylase (GAD) is the key enzyme of GABA synthesis in plants. Our previous transcriptome analysis found that PpGAD2 was significantly induced in watercore fruit; however, the mechanism through which PpGAD2 regulates watercore-induced hypoxia stress resistance in pears is unclear. The present study found that the fruit pulp ethanol, malondialdehyde (MDA) and H2O2 content was significantly inhibited by exogenous GABA. The transcript abundance of PpGAD2 was significantly higher than that of other PpGADs in watercore fruit or healthy fruit. Tissue expression showed that the content of PpGAD2 in mature fruit was higher than in young fruit. Moreover, subcellular localization showed that PpGAD2 was located in the cytoplasm. Transient overexpression assays suggested that PpGAD2 had a role in GABA synthesis. Several CML (calmodulin–like) genes were also significantly increased in watercore fruit. Moreover, PpWRKY53 was significantly induced in watercore fruit, and the GUS activity assay showed that PpWRKY53 can significantly increase the activity of the PpGAD2 promoter. Taken together, these results demonstrate that PpGAD2 played an important role in GABA synthesis to increase plants’ resistance to hypoxia stress, and its activity may be affected by PpWRKY53 and several watercore-induced CML genes.

‘Huangguan’ pear (Pyrus bretschneideri Rehd) fruit is susceptible to cold, characterized by developing peel browning spots (PBS) during cold storage. Additionally, ethylene pretreatment reduces chilling injury (CI) and inhibits PBS occurrence, but the mechanism of CI remains unclear. Here, we deciphered the dynamic transcriptional changes during the PBS occurrence with and without ethylene pretreatment via time-series transcriptome. We found that ethylene suppressed the cold-signaling gene expression, thereby decreasing the cold sensitivity of the ‘Huangguan’ fruit. Moreover, the “Yellow” module closely correlated with PBS occurrence was identified via weighted gene co-expression network analysis (WGCNA), and this module was related to plant defense via Gene Ontology (GO) enrichment analysis. Local motif enrichment analysis suggested that the “Yellow” module genes were regulated by ERF and WRKY transcription factors. Functional studies demonstrated that PbWRKY31 has a conserved WRKY domain, lacks transactivation activity, and localizes in the nucleus. PbWRKY31-overexpressed Arabidopsis were hypersensitive to cold, with higher expression levels of cold signaling and defense genes, suggesting that PbWRKY31 participates in regulating plant cold sensitivity. Collectively, our findings provide a comprehensive transcriptional overview of PBS occurrence and elucidate the molecular mechanism by which ethylene reduces the cold sensitivity of ‘Huangguan’ fruit as well as the potential role of PbWRKY31 in this process.

Glycine-aspartic acid-serine-leucine (GDSL) type lipases/esterases genes play critical roles in plant development and are related to the responses to abiotic and biotic stress. However, little is known about the GDSL family in pear (Pyrus spp.). Studies have shown GDSL-domain proteins play key roles in suberin deposition. Suberin deposition in the fruit epidermis, also called russeting, is an important defect that negatively affects consumer appeal in some fruit species, such as pear, apple and grapevine. Fruit russeting is mainly associated with cuticle microcracking and suberin accumulation in the inner part of the epidermal cell walls. To gain insight into the role of the GDSL gene family in suberin deposition and russet development in pear, we performed a genome-wide characterization of the GDSL family, including their identification, chromosomal localization, phylogenetic relationships, and expression patterns, in different tissues/organs in pear. One hundred and thirteen GDSL-type lipases/esterases genes were identified in the pear genome, and a phylogenetic analysis revealed that GDSL family can be classified into four distinct groups. Thirty GDSL genes were co-expressed with five homolog pear genes of three well-known suberin biosynthesis Arabidopsis genes (AtGPAT5, AtASFT, and AtCYP86B1) in the transcriptional co-expression network during pear fruit development. Among the 30 co-expressed GDSL genes, twelve genes were further analyzed by quantitative Real-time PCR, and the results showed the expression levels of the 12 genes were different between the russet exocarp and green exocarp of sand pear at different fruit development stages. Our study provides a detailed overview of the GDSL gene family and lays the foundation for future functional characterization of GDSL genes in P. bretschneideri.

‘Shannongsu’ and ‘Xincixiang’ were two new late-ripening pear cultivars with high quality, that were bred by our team. In order to clear the postharvest storage characteristics, mature pears were collected and stored at room temperature. Several fruit characteristics were evaluated over time, such as firmness, ethylene release rate, content of aroma components, softening-related enzyme activity, and gene expression. Both ‘Shannongsu’ and ‘Xincixiang’ were crisp and juicy stored after 60 d at room temperature, which exhibited excellent storage characteristics. The storability may be comprehensive result of low levels of ethylene production, aroma synthesis, softening-related activities, and gene expression. The research cleared the storage characteristics of ‘Shannongsu’ and ‘Xincixiang’ at room temperature for the first time, which will provide scientific theoretical guidance for fruit production and marketing.

Female weevils of the family Attelabidae (Coleoptera: Curculionoidea) possess a unique behaviour of partially cutting the branches connecting egg-bearing organs of their host plants during oviposition. However, the consequence of such behaviour remains unclear. Using Rhynchites foveipennis and its host pear (Pyrus pyrifolia), the present study tested the hypothesis that the oviposition behaviour could disarm the host plants’ defence. We compared the survival rates, growth rates, and performance of eggs and larvae under two conditions: (1) the fruit stems were naturally damaged by the females before and after oviposition, and (2) the fruit stems were artificially protected from the females. When fruit stems were protected from female damage, the survival rates of eggs and larvae were only 21.3–32.6%, respectively; and the larval weight was 3.2–4.1 mg 30 days after laying eggs. When the fruit stems were damaged, the survival rates of eggs and larvae reached 86.1–94.0%, respectively; and the larval weight reached 73.0–74.9 mg 30 days after laying eggs. The contents of tannin and flavonoids in the pears did not change significantly along with the oviposition and larval feeding, but weevil eggs were crushed and killed by the callus in the pears. Once the stunted larvae in branch-growing pears were moved into the picked-off ones, the growth and development recovered. The findings indicate that the oviposition behaviour can significantly increase the survival of the offspring. Our study suggested that the oviposition behaviour of attelabid weevils is a strategy to overcome plant defence.

Turkey is one of the countries that allow the cultivation of most plant species due to the different climate. In this study on apple, pear and quince species, which belong to these plant species and have economic importance, the projection status is to be calculated based on the data from TUIK. For the apple species in the study, the projection coefficient ranged from 20.71 to 19.58, while the average value of the projection coefficient was found to be 5.70. While the projection coefficients for pear species varied from - 2.78 to 6.51 and for quince species from - 23.01 to 37.68, the average projection coefficients for these species were determined to be 2.05 and 4.87, respectively. Depending on these projection coefficients, the production values of the three fruit species are predicted to increase in the coming years (without considering the effects of biotic and abiotic conditions)., Türkiye, sahip olduğu iklimin farklılık göstermesi sebebiyle çoğu bitki türünün yetişmesine imkân sağlayan ülkeler arasındadır. Bu bitki türleri arasında yer alan ve ekonomik öneme sahip olan elma, armut ve ayva türü üzerine yapılan bu çalışmada TÜİK verilerine bağlı olarak projeksiyon durumlarının hesaplanması amaçlanmıştır. Çalışmada incelenen elma türünde projeksiyon katsayısı -20,71 ile 19,58 arasında değişirken ortalama projeksiyon katsayı değeri 5,70 olarak belirlenmiştir. Armut türünde projeksiyon katsayıları -2,78 ile 6,51 arasında, ayva türünde ise -23,01 ile 37,68 arasında değişim gösterirken bu türlerde ortalama projeksiyon katsayıları sırasıyla 2,05 ile 4,87 olarak belirlenmiştir. Bu projeksiyon katsayılarına bağlı olarak üç meyve türünün gelecek yıllarda üretim değerlerinin (biyotik ve abiyotik koşulların etkisi göz ardı edilmek kaydıyla) artış göstereceği öngörülmektedir.

Nonhost resistance is the outcome of most plant/pathogen interactions, but it has rarely been described in Rosaceous fruit species. Apple (Malus x domesticaBorkh.) have a nonhost resistance toVenturia pyrina, the scab species attacking European pear (Pyrus communisL.). Reciprocally,P. communishave a nonhost resistance toVenturia inaequalis, the scab species attacking apple. The major objective of our study was to compare the scab nonhost resistance in apple and in European pear, at the phenotypic and transcriptomic levels. Macro- and microscopic observations after reciprocal scab inoculations indicated that, after a similar germination step, nonhost apple/V. pyrinainteraction remained nearly symptomless, whereas more hypersensitive reactions were observed during nonhost pear/V. inaequalisinteraction. Comparative transcriptomic analyses of apple and pear nonhost interactions withV. pyrinaandV. inaequalis, respectively, revealed differences. Very few differentially expressed genes were detected during apple/V. pyrinainteraction, preventing the inferring of underlying molecular mechanisms. On the contrary, numerous genes were differentially expressed during pear/V. inaequalisinteraction, allowing a deep deciphering. Pre-invasive defense, such as stomatal closure, could be inferred, as well as several post-invasive defense mechanisms (apoplastic reactive oxygen species accumulation, phytoalexin production and alterations of the epidermis composition). In addition, a comparative analysis between pear scab host and nonhost interactions indicated that, although specificities were observed, two major defense lines seems to be shared in these resistances: cell wall and cuticle potential modifications and phenylpropanoid pathway induction. This first deciphering of the molecular mechanisms underlying a nonhost scab resistance in pear offers new possibilities for the genetic engineering of sustainable scab resistance in this species. Concerning nonhost scab resistance in apple, further analyses must be considered with the aid of tools adapted to this resistance with very few cells engaged.

In the Mediterranean basin, agriculture and other forms of human land use have shaped the environment since ancient times. Intensive and extensive agricultural systems managed with a few cultured plant populations of improved varieties are a widespread reality in many Mediterranean countries. Despite this, historical cultural landscapes still exist in interior and less intensively managed rural areas. There, ancient fruit tree varieties have survived modern cultivation systems, preserving a unique genetic heritage. In this study, we mapped and characterized 106 living fruit trees of ancient varieties in the Basilicata region of southern Italy. Tree ages were determined through tree ring measurements and radiocarbon analyses. We uncovered some of the oldest scientifically dated fruit trees in the world. The oldest fruit species were olive (max age 680 ± 57 years), mulberry (647 ± 66 years), chestnut (636 ± 66 years), and pear (467 ± 89 years). These patriarchs hold a unique genetic resource; their preservation and genetic maintenance through agamic propagation are now promoted by the Lucan Agency for the Development and Innovation in Agriculture (ALSIA). Each tree also represents a hub for biodiversity conservation in agrarian ecosystems: their large architecture and time persistence guarantee ecological niches and micro-habitats suitable for flora and fauna species of conservation significance.

Cacopsylla pyri L. (Hemiptera: Psyllidae) je jedan od najvažnijih gospodarskih štetnika kruške. S obzirom na nove smjernice o održivoj uporabi pesticida i smanjenja rizika od negativnih učinaka pesticida stalno se iznalaze nova, ekološki prihvatljiva rješenja u zaštiti bilja. Cilj ovog istraživanja je bio utvrditi utjecaj biostimulatora na povećanje otpornosti kruške na intenzitet napada kruškine buhe. Istraživanje je obavljeno 2021. godine u pokusnom nasadu kruške, sorte Williams/BA 29, Poljoprivrednog instituta Osijek. U svrhu istraživanja obavljena su dva tretmana (T1 - Katon XT + Bombardier, T2 - kontrolni tretman - voda). Redovito praćenje brojnosti svih razvojnih stadija kruškine buhe provedeno je na prethodno obilježenim jednogodišnjim izbojcima pokusnog stabla u tri ponavljanja. Potvrđen je očekivani rezultat jednogodišnjeg istraživanja da je uporaba kombinacije biostimulatora dala statistički značajnu manju brojnost svih razvojnih stadija u odnosu na kontrolni tretman., Cacopsylla pyri L. (Hemiptera: Psyllidae) is one of the most important economic pests of pear. With regard to new guidelines on the sustainable use of pesticides and reducing the risk of negative effects of pesticides, new, environmentally friendly solutions are constantly being found in plant protection. The aim of this research was to determine the impact of biostimulators in pear production on increasing resistance to the harmful pear psylla population. The research was set up in 2021 in an experimental pear plantation of the Williams/ BA 29 variety of the Agricultural Institute Osijek in two treatments (T1- Katon XT + Bombardier, T2- control treatment - water). Regular monitoring of the abundance of all developmental stages of the pear psylla was done on marked one-year-old shoots of the experimental tree in three repetitions. The expected result of the one-year study was confirmed, that the use of a combination of biostimulators gave a statistically significant lower number of all developmental stages compared to the control treatment.

Аннотация. В связи с постоянным пополнением сортимента груши новыми популярными сортами, которые используются для закладки современных промышленных интенсивных насаждений, важное практическое значение приобретают исследования по изучению их основных фитометрических параметров. В статье приводятся результаты изучения силы роста дерева, формы кроны, площади листовой поверхности, формирования вегетативных и генеративных образований, урожайности и качества плодов. Исследования были проведены с использованием 18 сортов груши селекции Крымской опытной станции садоводства, Никитского ботанического сада и зарубежного происхождения, отличающихся по срокам созревания плодов. На основе изучения структуры плодовых образований у сортов груши установлено, что все они имеют смешанный тип плодоношения с преобладанием тех или иных генеративных образований в количественных показателях. Проведена группировка сортов по силе роста и габитусу кроны дерева. Выделены сорта со сдержанной силой роста дерева: Изюминка Крыма, Изумрудная, Десертная, Рада, Дива, Очарование Лета, Крымчанка, Таврическая, Мария. Данные корреляционного анализа позволили выявить отрицательный коэффициент корреляции (r=–0,16) между высотой дерева и урожайностью, а также положительный коэффициент (r=0,74) между площадью листовой поверхности дерева и урожайностью. Отмечена положительная прямая связь (r=0,50–0,64) урожайности с общей длиной побегов и количеством генеративных образований. Методом кластерного анализа на основе евклидова расстояния дана оценка основных фитометрических показателей. Выделены сорта с высокими показателями урожайности и качества плодов: Мария, Изюминка Крыма, Таврическая, Якимовская, Глория, Изумрудная, Десертная, Рада, Дива, Надежда, Очарование Лета, Крымская Ароматная, Крымская Медовая. Перечисленные сорта могут быть рекомендованы для использования в селекции и для промышленного выращивания., In connection with the constant replenishment of pear assortment with new popular cultivars, used for establishing modern industrial intensive plantations, the studies of their main phytometric parameters are of great practical importance now. This article presents the results of studying the growth vigor of trees, crown shape, leaf surface area, developing of vegetative and generative formations, cropping capacity and quality of fruits. The studies were carried out using 18 pear cultivars bred in the Crimean Experimental Horticulture Station, Nikitsky Botanical Garden and of foreign origin, different in terms of fruit ripening. Based on the structural study of fruit formations in pear cultivars, it was found that all of them have a mixed type of fruiting with predominance of certain generative formations in quantity indicators. Pear cultivars were grouped in accordance with a growth vigor and tree crown mien. Grouping of cultivars was carried out according to the strength of growth and habitus of tree crown. The cultivars with moderate growth vigor were identified: ‘Izyuminka Kryma’, ‘Izumrudnaya’, ‘Desertnaya’, ‘Rada’, ‘Diva’, ‘Ocharovaniye Leta’, ‘Krymchanka’, ‘Tavricheskaya’, ‘Mariya’. Correlation analysis data allowed us to reveal a negative correlation coefficient (r=–0.16) between the height of trees and cropping capacity, as well as a positive correlation coefficient (r=0.74) between leaf surface area and cropping capacity. A positive direct connection (r=0.50–0.64) of cropping capacity with a total shoot length, and a number of generative formations was noted. The method of cluster analysis based on the Euclidean distance helped to estimate basic phytometric indicators. The cultivars with high cropping capacity and fruit quality were identified: ‘Mariya’, ‘Izyuminka Kryma’, Tavricheskaya’, ‘Yakimovskaya’, ‘Gloria’, ‘Izumrudnaya’, ‘Dessertnaya’, ‘Rada’, ‘Diva’, ‘Nadezhda’, ‘Ocharovanye Leta’, ‘Krymskaya Aromatnaya’, ‘Krymskaya Medovaya’. The listed cultivars can be recommended for breeding and industrial cultivation., Magarach Vinogradstvo i Vinodelie, Выпуск 2 (124) 2023, Pages 170-176

The objective of this work is to evaluate the concentration of cyanogenic glycosides CGs (amygdalin and prunasin) in the cultivar and rootstock, as an indicator of compatibility in pear grafts. The work consists of two experiments. Experiment 1 evaluated Cascatense/Pyrus Calleryana and Cascatense/EMC combinations. Experiment 2 evaluated the combinations Packham’s Triumph/Adams, Santa Maria/Adams, and Rocha/Adams. The experimental design of the two experiments was randomized blocks with four replications. The evaluations were carried out in the spring and summer of the harvest 2014/2015. The results indicated graft compatibility in the Cascatense/P. Calleryana, Packham’s Triumph/Adams, and Rocha/Adams combinations; slight incompatibility of Santa Maria/Adams, and severe incompatibility of Cascatense/EMC. The obtained results indicate that differences ≥ 20 mg g-1 of CGs between scion and rootstock were correlated with a drastic reduction in vigor, problems of continuity in graft union, low yield, and early defoliation.

Hexanal slows down the ripening process in fresh produce by inhibiting the activity of phospholipase D, thereby increasing shelf life. This study focused on comparing the single time exposure and continuous exposure of post-harvest Anjou and Bartlett pears to hexanal by dipping or fumigating them to enhance their shelf life. Continuous exposure of hexanal was achieved by developing a hexanal encapsulated fiber (HEF), which releases hexanal vapor due to the increased humidity (96 ± 2% RH) in the container headspace as a result of respiration. The fruits were stored in cold storage (0 ± 2 °C) as well as at normal room temperature (20 ± 2 °C) and their storage capacity was compared between the treatments. Fruit parameters such as physiological loss of weight (PLW), firmness, and total soluble solids (TSS) showed only minor differences between hexanal treated and untreated fruits. Between the two varieties, Anjou exhibited slightly higher values than Bartlett. However, when the fruits are visually evaluated, the main aspect of consumer preference, HEF-treated fruits had a better appeal in both varieties and in both conditions. Bartlett responded better than Anjou even in cold storage conditions, suggesting that there are varietal differences in their response to hexanal. Both hexanal treatments helped color retention and reduced fungal infection under the storage conditions tested.

Cactus pear is a dominant crop to arid lands with high nutritional value. Its fruits are used in food processing as add value to food products. The current study planted cactus pear under three irrigation regimes (T1, T2, and T3) where two of them (T2 and T3) implicated severe deficit irrigation conditions on the crop. The relationship between applied irrigation water regimes and fruit physical and chemical properties including antioxidants, pigment and vitamin C content was studied. The study also aimed to utilize cactus pear’s pulp (CPP), as additive value, in the processing of wheat flour cupcake. Samples of cupcake were made by adding 20%, 40%, 60% and 80% CPP based on wheat flour weight. Fruits obtained under T2 and T3 treatments had higher color concentration than T1. T2 irrigation regime yielded higher content of total phenolic and flavonoid content (TPC and TFC) than those produced under T3 and T1. Antioxidant activity was the highest in T2. Thus, fruit pulp obtained from T2 was selected for cupcake making. The content of soluble solids was ⁓18 Brix in all treatments. VitC. was significantly higher (P≤0.05) in T3 (56.04 g AA/kg) than T1 (55.42 g AA/kg) and T2 (51.01 AA/kg). The content of betacyanins in T1 was higher (0.47 mg100mg dry weight) in fruits pulp than T2 and T3 (0.44 and 0.54 mg100mg dry weight). Sensory evaluation showed that fortification with 60% cactus pear pulp had the best sensory characteristics meanwhile cupcakes fortified with 80% cactus pear pulp was not acceptable.

The objective of the work was to determine the antioxidant potential in vitro of freeze-dried peel extracts of 20 fruits from the northern region of Peru through five tests (Folin-Ciocalteu, DPPH., ABTS+., FRAP and CUPRAC). According to multivariate statistical analyzes, five groups were found: (i.) peel extracts with the highest values of antioxidant capacity (AC) from custard apple, and star fruit; (ii.) rind extracts with high AC values from quince, sweet granadilla, guava, and black grape; (iii.) husk extracts with middle values of AC from passion fruit, and red mombin; (iv.) shell extracts with low AC values from tangerine, mandarine, and bitter orange; and, (v.) coating extracts with the lowest AC values from pawpaw, red pawpaw, muskmelon, dragon fruit, yellow and red indian figs, pear, apple, and green grape. To conclude, the fruit lyophilized-husk extracts of custard apple, star fruit, quince, sweet granadilla, guava, and black grape obtained the best AC.

The resistant phenotype of pear cultivars includes either complete resistance or tolerance to the attack by the causative agent of fire blight. The effect of ferritin and active iron (Fe2+) concentrations was compared in resistant (Dargazi), tolerant (Harrow Sweet), and susceptible (Bartlett) pear cultivars inoculated with a wild type strain of Erwinia amylovora (Ea273). The examination of necrosis revealed that resistance to the disease manifested itself as a delay in the appearance of symptoms and progression of the disease. Despite a rise in ferritin levels in all cultivars following disease agent inoculation, resistant and tolerant cultivars showed greater ferritin levels than susceptible cultivar. In addition, only resistant and tolerant cultivars displayed a drop in Fe2+ levels. The rate of decrease in Fe2+ content in Dargazi and Harrow sweet cultivars was 28 and 33%, respectively. Hydrogen peroxide (H2O2) and hydroxyl radical (OH•−) accumulation and intensities were considerably distinctive. Furthermore, tolerant and sensitive cultivars started producing OH•− radicals faster than resistant cultivar. According to these findings, different pathways are employed by pear cultivars to respond to the causative agent of fire blight.

Pear has an S-RNase-based gametophytic self-incompatibility (SI) system. Nuclear DNA degradation is a typical feature of incompatible pollen tube death, and is among the many physiological functions of vacuoles. However, the specific changes that occur in vacuoles, as well as the associated regulatory mechanism in pear SI, are currently unclear. Although research in tobacco has shown that, decreased activity of diacylglycerol kinase (DGK) results in the morphological change of pollen tube vacuole, whether DGK regulates the pollen tube vacuole of tree plants and whether it occurs in SI response, is currently unclear. We found DGK activity is essential for pear pollen tube growth, and DGK4 regulates pollen tube vacuole morphology following its high expression and deposition at the tip and shank edge of the pollen tube of pear. Specifically, incompatible S-RNase may induce cytoplasmic acidification of the pollen tube by inhibiting V-ATPase V0 dominant a1 subunit gene expression as early as 30 min after treatment, when the pollen tube is still alive. Cytoplasmic acidification induced by incompatible S-RNase resulting in reduced DGK4 abundance and deposition, leading to morphological change of the vacuole and fragmentation of nuclear DNA, which indicates DGK4 is a key factor in pear SI response. This article is protected by copyright. All rights reserved.

Introduction: Opuntia ficus-indica is a well adapted cactus to extreme climatic environments. In the usual diet and food industry, it is an interesting source of food ingredients. In general, the protective role of prickly pears has been due to their antioxidant components, phenolic compounds, and some minor components present in the content of seed oil and seed protein and the oil from cactus pear seed has been found with high levels of unsaturated fatty acids ,with antioxidant and antimicrobial activity as well as cardioprotective, antithrombotic, anti-inflammatory, antiarrhythmic, hypolipidemic, and antihyperglycemic effect. Aim: To evaluate the in vitro antimicrobial activity of Opuntia ficus-indica seed oil against Streptococcus mutans. Materials and Methods: Broth microdilution assay was performed by following modifications: Brain heart infusion (BHI) broth was prepared and sterilise at 121c for 15lbs, the 100 microlitre of streptococcus mutans inoculated at freshly prepared broth and incubated at 37c for 24 hours. Then BHI broth prepared with sucrose and serial two fold dilution were done with 160microlitre broth and 40 microlitre prickly pear seed oil. Then 20 microlitre of culture was added. Column 11 contains BHI using sterile micro pipettes and the plates were incubated at 30 c for 18 hours. The growth of bacteria was visualised and lowest concentration with no visible growth was recorded as MIC. Results: This study results shows that, by broth microdilution method at concentration ranging from 10%-0.039% v/v, Opuntia ficus-indica seed oil potentially inhibits the growth of streptococcus mutans at the concentration of 0.03% (v/v). Conclusion: From the study, the results demonstrated that Opuntia ficus-indica seed oil shows noticeable antimicrobial activity against streptococcus mutans. Use of essential oils against oral pathogens can be an alternative to other antimicrobial agents which could be cheap and effective modules used in control of bacteria which are responsible for oral infections.

Food security is threatened in Southern Africa, because of unpredictable droughts and higher summer temperatures brought on by climate change and global warming. Durable and hardy plants that grow easily and quickly in such conditions must be adopted to ensure sustainable and reliable food supplies. The young cladodes (nopalitos) from the cactus pear plant, which adapts to hot and dry climates, is an underutilised alternative food source that can serve as a healthy vegetable. It thrives in many environments such as deserts, below sea level, high altitude regions and tropical regions with temperatures above 50°C. Nopalitos are a traditional staple vegetable and have been consumed in Mexico for over 9000 years. However, it is underutilised and unknown as an alternative vegetable in Africa. Research on the physiochemical and nutritional content has been conducted. However, the information on harvesting nopalitos from cultivars available in South Africa for optimal edible quality is not available. Good quality nopalitos are young, thin, bright green, soft, fresh and not too sour or slimy. This paper aims to identify the effect of and the interaction between size, cultivar and harvesting season to obtain optimal eating quality. Data were obtained for two cultivars (Morado and Fusicaulis) at 9 cm, 12 cm, 15 cm, 18 cm, 21 cm and 24 cm, which were harvested in spring (October) and autumn (March) over two years. The quality characteristics were translated into the measurable attributes of morphology (weight, width, diameter, volume and surface area), texture (firmness and compressibility), colour (L*, a*, b*, C*and h°), turgidity (moisture content, mucilage yield and viscosity) and gustatory (percentage titratable acidity, pH and total soluble solids). ANOVA and Principal Component Analyses were performed to determine significant differences and interactions between the length groups, two cultivars and two seasons. The results showed that the size, cultivar and season influenced the edible characteristics. Both cultivars were most tender at 15 cm and presented the best edible qualities in spring. Morado showed better colour, turgidity and gustatory qualities. Morado was thinner, a brighter green colour, less sour and less slimy compared to Fusicaulis nopalitos.

Pears are one of the oldest and the third most important fruit species grown in temperate regions. They are consumed because of their nutritional and health benefits, in fresh form or as various processed products. This article resolves the etiology of the Penicillium-like mold symptoms on pear fruits in Serbia. Samples of pear fruits with blue mold and other Penicillium-like mold symptoms were collected in Serbia from 2016 to 2019, from four storages. The recovered isolates were identified and characterized according to a polyphasic approach. Morphological and physiological analyses were performed on three media and five temperatures, respectively. Four loci (internal transcribed spacer, beta-tubulin, calmodulin, and DNA-dependent RNA polymerase II second largest subunit) were used for sequencing, genetic identification, and phylogenetic analyses. The results of the identification by conventional and molecular methods were in agreement, and they revealed that the obtained isolates belong to five species: Penicillium crustosum, P. expansum, P. italicum, Talaromyces minioluteus, and T. rugulosus. In a pathogenicity test, P. crustosum, P. expansum, T. minioluteus, and T. rugulosus produced decay on artificially inoculated pear fruits, and P. italicum induced tissue response lesions. The results of this study are the first reports of T. minioluteus and T. rugulosus as postharvest pear pathogens. Also, these are the first world records of T. minioluteus, T. rugulosus, and P. italicum on fruits of European pear. Furthermore, this is the first finding of P. crustosum, P. expansum, P. italicum, T. minioluteus, and T. rugulosus on pear fruit in Serbia.

In addition to their use in traditional medicine, cactus pear (Opuntia species) are a source of vegetal nutrients in many countries. The aims of this study were to determine variability in the nutritional value of 42 spineless cactus pear cultivars, identify correlations between nutritional traits, and determine superior cultivars based on cladode nutritional value. Cladodes of 42 spineless cactus pear cultivars grown under the same glasshouse conditions were collected from the Roodeplaat research farm of the Agricultural Research Council, South Africa. The sliced, dried and powdered cladodes were subjected to quantitative analysis of their vitamin C, β-carotene and mineral element contents. Significant variations in nutritional values were observed among the different cultivars. Vitamin C content ranged from 8.95 mg/100 g in cultivar Ofer to 124 mg/100 g in cultivar Malta, whilst β-carotene content ranged from 3.9 mg/100 g in cultivar Murado to 31.4 mg/100 g in cultivar Cross X. Potassium and calcium were the most abundant mineral elements present, whilst iron was found to be the least present among the mineral elements quantified. A significant positive association was established between calcium (Ca), potassium (K) and zinc (Zn) contents. A direct selection for increased concentration of Ca could be a selection criterion for the development of population with an indirect improvement of K and Zn concentrations. The observed variations highlight the need for a careful cultivar selection for population and product development using spineless cactus pear cladodes.

Probiotic yoghurt with fruit was produced to enrich the intestinal flora of infants and to prevent various ailments in infants when the flora is inadequate. Peach, apple and pear purees (10% and 20% each), cow milk, milk powder, starter culture (combination of Streptococcus thermophilus, Lactobacillus delbrueckii ssp. bulgaricus, Bifidobacterium infantis, Bifidobacterium bifidum, Bifidobacterium longum and Lactobacillus paracasei) were used in the production of probiotic yogurt for babies. Some properties of yoghurt samples were investigated during fermentation and on the 1st, 7th, 14th and 21st days of storage. After ten hours of fermentation, the lowest pH was observed in samples with apple puree. It has been determined that syneresis increases with increasing concentrations of fruit purees. The water holding capacity was less in yoghurts containing fruit puree compared to control yoghurt and in 20% fruit puree compared to yoghurts containing 10% fruit puree. The number of L. bulgaricus generally increased in all samples during storage. It was determined that the number of S. thermophilus in control sample was higher than other samples during storage. The number of L. paracasei and Bifidobacterium spp. decreased during storage. While the control sample remained probiotic until the 14th day of storage, other samples lost its probiotic properties before the 7th day of storage. Considering that the number of probiotic microorganisms in a probiotic product should be at least 106-107 CFU/g according to FAO, it has been decided that the most suitable fruits for probiotic yogurt with fruit puree are peach and apple, respectively. Considering the structural features, it is more appropriate to use 10% fruit puree, and considering the probiotic feature, it is more appropriate to use 20% fruit puree. Choosing the appropriate packaging and fixing suitable storage conditions will help probiotic microorganisms to preserve their vitality for a long time.

Pear as a fruit species has a special place because of its quality characteristic. The fact that about 20,000 pear seedlings are considered to be sold annually in Bosnia and Herzegovina, which are autochthonous or spontaneously expanded varieties, also speaks in favor. The main goal of this research is to analyze the genetic variability of nine autochthonous pear varieties in Tuzla Canton, Bosnia and Herzegovina to enable the conservation and expansion of existing genetic resources. The study included nine autochthonous pear varieties. Samples of young leaves were collected on the following localities: the town of Srebrenik, the town of Gradačac, the municipality of Čelić-Tuzla Canton, Bosnia and Herzegovina, in the spring 2019. To determine genetic diversity, 12 SSR (Simple Sequence Repeats) markers were genotyped. There were no cases of synonyms or homonyms in the analyzed set. Each of the nine tested varieties represents a unique genotype. Autochthonous pear cultivars analyzed in this paper represent an interesting genetic resource, with useful agronomic traits that can be used in future cultivation.

The comparison of the influence of foliar fertilization with four preparations on the growth of ‘Conference’ maiden pear trees growing on MA quince rootstock was conducted in a nursery in a three-year period. The evaluation was conducted on the basis of maidens growth parameters and the state of their leaf minerals content as well as on photosynthetic activity of the maiden trees. The preparations used in the experiment affected the improvement of some growth parameters studied, especially the stem diameter and fresh mass of the maidens. Biopuls Original turned out to be the best preparation as it improved significantly three out of five studied growth parameters. A varied impact of the preparations used on the content of micro and macro-elements in leaves was detected. All tested preparations positively influenced the leaves area index of maiden trees except for Blackjak preparation. Photosynthetic intensity of maiden pear trees nourished through leaves was significantly smaller in comparison with the control. Only plants treated with Biopulus Original were characterized by a higher concentration of CO2 and its level in intercellular space. The aim of the second experiment was to check the influence of the application of Trifender WP preparation with hydrogel on the growth of ‘Champion’ maiden quince trees at the stage of planting the rootstocks into a nursery. A better branching of the rootstocks was obtained after the use of the preparation with hydrogel and the hydrogel alone. The trees in these combinations were also characterized by bigger fresh and dry mass of the leaves. The influence of Trifinder WP applied in connection with hydrogel was the best.

The occurrence of water-soaked brown flesh in pear fruit is closely related to an activated biological Maillard reaction during the latter half of maturation. In this study, samples of immature and mature pear fruits were assessed for the incidence of water-soaked brown flesh (WSBF), sugar content, expression level of sugar metabolism-related genes, and activity of the Maillard and oxidative stress reactions. The occurrence of WSBF disorder was rare in immature fruit, but was pronounced in mature fruit. Glucose content of the flesh was higher in mature fruit with WSBF than in immature fruit without WSBF. Conversely, sucrose content was inversely correlated to glucose content. Higher levels of the neutral invertase gene (PpNIV) were detected in mature fruit compared with immature fruit. Levels of oxidative stress and Maillard reaction products in the flesh of mature fruit were determined. The strongest Maillard and oxidative stress reactions were observed in cells adjacent to the vascular bundle, and these reactions diminished with distance from the vascular bundle. Furthermore, examination of cells near the vascular bundle revealed stronger signal intensity on the phloem side compared to the xylem side. Cellular examination of the phloem side of immature and mature fruits indicated that mature fruit had a stronger signal intensity than immature fruit in both reactions. These results suggest that an increase in the Maillard reaction, attributed to an increased concentration of reducing sugars, during the maturation period may be fundamentally involved in the occurrence of this disorder through oxidative stress.

Recently, Cadophoraluteo-olivacea has been reported as a post-harvest pathogen of side rot of apple (Malusdomestica) in Latvia, and of pear (Pyruscommunis) in Italy and the Netherlands. In 2018 and 2019, in South Tyrol (northern Italy) 11 fungal cultures, identified as C.luteo-olivacea based on ITS (internal transcribed spacer region) sequence data, were obtained from apple fruit displaying post-harvest side rot symptoms. The fruit were sampled in packinghouses representing different apple growing areas of South Tyrol. For a more accurate taxonomic assignment, two additional molecular genetic loci, β-tubulin (TUB2) and translation elongation factor 1α (TEF-1α), of seven isolates were amplified and sequenced. Phylogenetic analysis based on multi-locus DNA sequence data confirmed that isolates from apple fruit with side rot symptoms indeed represented C.luteo-olivacea. A pathogenicity test performed on apple fruit of ‘Golden Delicious’ confirmed the virulence of a representative isolate. So far, C.luteo-olivacea represents a minor post-harvest pathogen of apple but considering the losses that this fungus can cause to other crops, the awareness about this potential apple disease should be raised.

The present study focuses on the effect of temperature and extraction methods on the yields, chemical quality, fatty acids, and tocopherols of the oil extracted from the seeds of Opuntia ficus-indica, collected in the eastern region of Morocco. Our results revealed the effect of temperature that when we increase the temperature used, the yields also increase; the results also showed that this high temperature does not affect the physicochemical properties, fatty acids, and tocopherols. Thus, the results of this study revealed that the prickly pear is a rich source of oil; the obtained oil yields varied from 12.49%±0.09 for mechanical extraction, 11.46±0.10 for chemical extraction, and 10.52%±0.09 for maceration. The main fatty acids founded in Opuntia ficus-indica are linoleic acid 75.80%±0.10 (chemical), 74.07%±0.14 (maceration), and 71.59%±0.14 (mechanical) and palmitic acid 17.32%±0.02 (chemical), 22.419%±0.06 (maceration), and 26.58%±0.00 (mechanical); prickly pear oil could be classified as a linoleic acid. The physicochemical properties of Opuntia ficus-indica seed oils such as acid index mgKOH/g oil (4,376±0.10, 5.854±0.03, 5.667±0.07), saponification value mgKOH/g oil (181.12 ±0.18, 183.77±1.23, 179.08±3.45), and peroxide value 20milieq/Kg (5.75±0.08, 6±0.06, 5.97±0.04) for mechanical, chemical, and maceration extraction, respectively, density, and refractive index were all found to be in good accordance with quality criteria for both pure and fresh oils. Among the tocopherols found, a high value of γ-tocopherol was detected in mechanical extraction with 502.04±0.76 mg/kg, followed by chemical extraction and maceration with 430.12±0.61mg/kg and 315.47±0.96 mg/kg, respectively.

Previous studies have only focused on the bioaccessibility of single pesticide/metal without considering the potential impact of post-uptake interactions on bioaccessibility of pesticides/metals in the human digestive system. Hence, the influences of chromium (Cr) speciation on neonicotinoids bioaccessibility were investigated and the potential health risk based on the oral bioaccessibility was evaluated. Bioaccessibility of four neonicotinoids in apple and pear was measured using three common in vitro methods (SBRC, PBET, and IVG). Bioaccessibility of neonicotinoids in apple and pear varied between in vitro methods, which may reflect the difference of determination parameters (i.e., pH values, incubation time, and constituents). The neonicotinoids bioaccessibility was remarkably reduced by 17.21–81.21% and 11.61–73.70% with the addition of Cr(III) and Cr(VI), respectively. Risk assessment based on the hazard quotient (HQ) with bioaccessibility revealed that exposure to pesticide residues in the tested fruits were all below levels that might pose a health risk. These findings are of theoretical value for the safety evaluation of pesticide residues on food.

Background. Natural populations of fruit and small fruit plants in Belarus and their specific and varietal composition for a long time attracted the attention of pomologists and breeders. Identification and mobilization of unique local forms and landraces as genetic sources of useful traits as well as monitoring duplicate collections will contribute to their more effective use in breeding practice to develop competitive domestic cultivars of various crops and reveal the adaptability of foreign cultivars to the conditions of Belarus.Methods. The itinerary of the collecting mission passed through 6 regions of the Republic of Belarus (Gomel, Minsk, Mogilev, Vitebsk, Brest, and Grodno) in 2012–2017.Results. As a result, 221 samples of fruit, small fruit and nut plants were collected, including 18 rootstocks of fruit crops. By 2021, 105 unique landraces were tested in the plant introduction and quarantine nursery and planted in the field gene bank, including 28 accessions of apple, 33 of pear, 11 of sour cherry, 5 of sweet cherry, 9 of plum, 8 of apricot, 1 of almond, 2 of hazel, 3 of garden strawberry, 1 of black chokeberry, 1 of viburnum, and 1 of bird cherry. There are plans to use the obtained accessions in breeding practice assources of valuable agronomic traits (high winter hardiness, high yield, resistance to a set of plant pathogens, etc.).

Erwinia amylovora is a plant pathogen causing necrotrophic fire blight disease of apple, pear, and other rosaceous plants. This bacterium colonizes host vascular tissues via the production of exopolysaccharides (EPSs) including amylovoran. It is well-established that the nearly ubiquitous plasmid pEA29 of E. amylovora is an essential virulence factor, but the underlying mechanism remains uncharacterized. Here, we demonstrated that pEA29 was required for E. amylovora to produce amylovoran and to form a biofilm, and this regulation was dependent on the thiamine biosynthesis operon thiOSGF. We then conducted carbohydrate and genetic analyses demonstrating that the thiamine-mediated effect on amylovoran production was indirect, as cells lacking thiOSGF produced an EPS that did not contain glucuronic acid, one of the key components of amylovoran, whereas the transcriptional activity and RNA levels of the amylovoran biosynthesis genes were not altered. Alternatively, addition of exogenous thiamine restored amylovoran production in the pEA29-cured strain of E. amylovora and positively impacted amylovoran production in a dose-dependent manner. Individual deletion of several chromosomal thiamine biosynthesis genes also affected amylovoran production, implying that a complete thiamine biosynthesis pathway is required for the thiamine-mediated effect on amylovoran production in E. amylovora. Finally, we determined that an imbalanced tricarboxylic acid cycle negatively affected amylovoran production, which was restored by addition of exogenous thiamine or overexpression of the thiOSGF operon. In summary, our report revealed a novel signaling pathway that impacts E. amylovora virulence in which thiamine biosynthesis enhances bacterial respiration that provides energetic requirements for the biosynthesis of EPS amylovoran. [Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .