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Different commercially available culture media have been long in use for microorganisms. But in Tigray, Ethiopia, the high price and scarcity of these culture media on local market have made it difficult for microbial researchers to conduct their research. The aim of current study was to create a low-cost, locally accessible culture medium for Lactobacillus species growth using cladodes extracted from cactus pear (Opuntia ficus-indica) cladodes. Samples of cactus pear cladode were collected from Adigrat, Tigray, Ethiopia. Lactobacillus reuteri and Lactobacillus mali were the two bacterial species that were examined. Evaluation and comparison of Lactobacillus species growth on cactus pear cladode agar and broth (40, 20 and 13.33 g/L) with de Man, Rogosa, and Sharpe (MRS) medium (control) were conducted. Each prepared cactus pear cladode agar (CPCA) medium was transparent and light brown in color. The current finding shows that after 72 h of incubation, both tested Lactobacillus species produced small, spherical and white colonies on CPCA that lacked any pigments or odor. In comparison to other cactus pear cladode broths (40 and 13.33 g/L), the cactus pear cladode broth (20 g/L) showed the fastest exponential growth after 24–36 h of incubation. The bacterial colony counts in the cactus pear cladode broth (20 g/L) were higher than those in the other formulations (40 and 13.33 g/L), but they did not differ significantly (P < 0.05) when compared to MRS medium. This study showed that the cactus pear cladode (20 g/L) medium could be used as a culture medium for Lactobacillus growth. [ABSTRACT FROM AUTHOR]

Background: Anthracnose, mainly caused by Colletotrichum fructicola, leads to severe losses in pear production. However, there is limited information available regarding the molecular response to anthracnose in pears. Results: In this study, the anthracnose-resistant variety 'Seli' and susceptible pear cultivar 'Cuiguan' were subjected to transcriptome analysis following C. fructicola inoculation at 6 and 24 h using RNA sequencing. A total of 3186 differentially expressed genes were detected in 'Seli' and 'Cuiguan' using Illumina sequencing technology. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses indicated that the transcriptional response of pears to C. fructicola infection included responses to reactive oxygen species, phytohormone signaling, phenylpropanoid biosynthesis, and secondary metabolite biosynthetic processes. Moreover, the mitogen-activated protein kinase (MAPK) signaling pathway and phenylpropanoid biosynthesis were involved in the defense of 'Seli'. Furthermore, the gene coexpression network data showed that genes related to plant–pathogen interactions were associated with C. fructicola resistance in 'Seli' at the early stage. Conclusion: Our results showed that the activation of specific genes in MAPK, calcium signaling pathways and phenylpropanoid biosynthesis was highly related to C. fructicola resistance in 'Seli' and providing several potential candidate genes for breeding anthracnose-resistant pear varieties. [ABSTRACT FROM AUTHOR]

Pear pollination is performed by artificial pollination because the pollination rate through insect pollination is not stable. Pollen must be collected to secure sufficient pollen for artificial pollination. However, recently, collecting sufficient amounts of pollen in Japan has become difficult, resulting in increased imports from overseas. To solve this problem, improving the efficiency of pollen collection and strengthening the domestic supply and demand system is necessary. In this study, we proposed an Artificial Intelligence (AI)-based method to estimate the amount of pear pollen. The proposed method used a deep learning-based object detection algorithm, You Only Look Once (YOLO), to classify and detect flower shapes in five stages, from bud to flowering, and to estimate the pollen amount. In this study, the performance of the proposed method was discussed by analyzing the accuracy and error of classification for multiple flower varieties. Although this study only discussed the performance of estimating the amount of pollen collected, in the future, we aim to establish a technique for estimating the time of maximum pollen collection using the method proposed in this study. [ABSTRACT FROM AUTHOR]

Monitoring the sanitary status of a large population of vegetative propagation materials is a challenge because it requires expensive and time-consuming testing. Here we report a group testing strategy to identify individual plants carrying viruses and/or a viroid in Pyrus betulifolia seedlings and virus-tested pear mother plants. First, the effect of pool size on RT-PCR detection of apple stem grooving virus (ASGV), apple stem pitting virus (ASPV), apple chlorotic leaf spot virus (ACLSV) and apple scar skin viroid (ASSVd) was evaluated; all of them could be sensitively detected in a bulk (pool) of eight samples. The virological condition of 2770 P. betulifolia seedlings and 110 virus-tested pear mother plants were then investigated by RT-PCR using a grouping strategy with 5 samples. We identified 20, 35 and 3 P. betulifolia seedlings as positive for ASGV, ASPV, and ASSVd, respectively, and 4 pear mother plants were identified as carrying ASGV. Our data indicated that RT-PCR testing on samples pooled before RNA extraction is a reliable and resource-efficient strategy to monitor the sanitary status of large numbers of pear vegetative propagation materials. The results presented here also highlight the possibility of pear seedling rootstocks being a source of viral infection. [ABSTRACT FROM AUTHOR]

‘Jinhyang’ is a fragrant pear bred in 2019. Field crossings to breed fragrant pears were conducted in 1984 at the Pear Research Center of the National Institute of Horticultural and Herbal Science. The maternal and paternal parents were ‘Okusankichi’ (IT254489) and ‘Hori’ (IT226291), respectively. The 84-16-5 line, which had a good fragrance, was first selected in 2007, and regional adaptation tests were conducted from 2011 to 2019 in five regions (Suwon, Chuncheon, Jinju, Yecheon, and Naju). The morphological characteristics of ‘Jinhyang’ include vigorous spreading tree form, brown-colored one-year-old shoot, elliptical leaf blade, round leaf tip, and white-colored flowers. The full bloom date was April 11, and the harvest date was in late September. The fruit of ‘Jinhyang’ weighs 439.9 g and has a soluble solid content of 13.0 °Brix, with a good sugar-acid balance and abundant juice. Analysis of the fragrance components of ‘Jinhyang’ revealed the presence of a large amount of fragrant volatile compounds compared to that of the standard cultivar ‘Niitaka’. In particular, ‘Jinhyang’ contains ethyl hexanoate and ethyl butanoate, which are known volatile compounds generated by pineapple and mango. Because of its strong uprightness, cultivation management, such as shoot bending, is necessary to maintain flower buds [ABSTRACT FROM AUTHOR]

Patulin is a mycotoxin produced by several species of Penicillium sp., Aspergillus sp., and Byssochlamys sp. on apples and pears. Most studies have been focused on Penicillium expansum , a common postharvest pathogen, but little is known about the characteristics of Penicillium paneum. In the present study, we evaluated the effects of temperature, pH, and relative humidity (RH) on the growth of P. paneum OM1, which was isolated from pears, and its patulin production. The fungal strain showed the highest growth rate at 25 °C and pH 4.5 on pear puree agar medium (PPAM) under 97 % RH, while it produced the highest amount of patulin at 20 °C and pH 4.5 on PPAM under 97 % RH. Moreover, RT-qPCR analysis of relative expression levels of 5 patulin biosynthetic genes (patA , patE , patK , patL, and patN) in P. paneum OM1 exhibited that the expression of the 4 patulin biosynthetic genes except patL was up-regulated in YES medium (patulin conducive), while it was not in PDB medium (patulin non-conducive). Our data demonstrated that the 3 major environmental parameters had significant impact on the growth of P. paneum OM1 and its patulin production. These results could be exploited to prevent patulin contamination by P. paneum OM1 during pear storage • The highest growth of P. paneum OM1 at 25 °C and pH 4.5 under 97 % relative humidity. • The highest patulin production by the fungus at 20 °C and pH 4.5 under 97 % relative humidity. • The expression of patA , patE , patK , and patN was up-regulated in YES medium. • The expression of patA , patE , patK , and patN was not up-regulated in PDB medium. • The expression of patL remained constantly in both YES and PDB media. [ABSTRACT FROM AUTHOR]

Warning: Aboriginal and Torres Strait Islander readers should be aware that this document may contain sensitive information, images or names of people who have since passed away. Context: Two Peoples Bay Nature Reserve on Western Australia's south coast is world renowned for its biodiversity, particularly its threatened fauna. Future co-management of the Reserve with Aboriginal peoples is likely, although very little information on the Noongar cultural heritage of the Reserve has been published and thus available for stewardship guidance. Methods: This study used oral history interviews on Country based on open-ended questioning and respect for intellectual property. Comprehensive surveys for Noongar cultural heritage were conducted on foot on the Reserve. Key results: A rich trove of women's and men's stories from the Knapp family about Two Peoples Bay is recalled and recorded. The Reserve features prominently in Wiernyert/Dreaming stories with classical human moral dilemmas, and transformations for wrong-doing are featured. Threatened animals and important plants are named as borongur/totems. Trading of gidj/spears of Taxandria juniperina is prominent. Use of fire traditionally was circumspect, and is confined to small areas and pathways in lowlands. Granite rocks are replete with lizard traps, standing stones, and stone arrangements. Conclusions: The Reserve has a long and layered oral history for Merningar Bardok Noongars, exemplified here by the Knapp family, members of which have enjoyed continuous oral history for countless generations. Granite rocks, wetlands, flora, and fauna are vitally important vessels of such knowledge. Implications: Cultural suppression has inhibited free cross-cultural exchange of kaatidjin/knowledge until recently. As respect for culture and Elders becomes paramount, positive co-stewardship of the Reserve will become a reality. Vibrant cultural interpretation and active management by Noongar guides and rangers is recommended. Warning: Aboriginal and Torres Strait Islander readers should be aware that this document may contain sensitive information, images or names of people who have since passed away. Future co-management of Two Peoples Bay Nature Reserve Reserve with Aboriginal peoples is likely, although very little information on the Noongar cultural heritage of the Reserve has been published and thus is available for stewardship guidance. Published for the first time, a rich trove of women's and men's stories from the Merningar Knapp family about Two Peoples Bay includes Wiernyert/Dreaming stories with classical human moral dilemmas, trading of gidj/spears, and stone structures on granite. Some Noongar names for landforms are provided. This article belongs to the Collection The Natural History of Two Peoples Bay Nature Reserve, Western Australia. [ABSTRACT FROM AUTHOR]

Fragrant pears have been one of the most favorite types in pear industry. However, manual picking cannot fully meet the demands of large-scale production, due to the labor intensity. Mechanical picking has the potential to significantly reduce the labor demands for the high productivity. Among them, the visual recognition has been one of the most key elements among the various picking robots. The complex orchard environment with the variable lighting, weather conditions, foliage obstructions and fruit overlap has also posed the significant challenges on both conventional image processing and machine learning-based object detection, thereby impeding the accurate identification of fragrant pears. This study aims to improve the accuracy and detection speeds in such unstructured settings. An optimized YOLOv8n-based object detection was introduced to specifically identify the fragrant pear. A dataset was also comprised of 4 500 images of fragrant pears. A variety of conditions were considered using image collection and data augmentation, such as different lighting and foliage obstructions within orchard environments. The Min-Max normalization was employed to consider the fragrant pear harvesting. A comprehensive evaluation was conducted on five lightweight YOLO versions: YOLOv3-tiny, YOLOv5n, YOLO6n, YOLOv7-tiny, and YOLOv8n. Different weights were assigned to optimize the model selection, in terms of the mAP, precision, recall, inference time, parameters and model size. The network structure was streamlined for the object detection of fragrant pear with YOLOv8n as the baseline. Four key areas were focused to optimize the model. Initially, the network backbone was redesigned to promote the network inference speed. The impact of the C2f structure on speed was assessed to replace the certain redundant C2f components. Subsequently, an effective PConv module was integrated into the detection head of network, in order to better recognize the obscured images. A weight-sharing strategy was also coupled with the detection head parameters to reduce the parameters. Additionally, the combination of simSPPF and Inner IoU was further augmented the inference speed and bounding box regression performance. Comparative trials were then conducted on the object detection of fragrant pear. The results revealed that the superior comprehensive performance was achieved in the YOLOv8n. A higher weighted score of 83.4% was obtained after the Min-Max normalization, compared with the YOLOv3-tiny, YOLOv5n, YOLOv6n, and YOLOv7-tiny. Thus, the baseline network was selected for the subsequent research. Optimization experiments were carried out with C2f structures. The replacement of C2f was identified in the 15th and 2nd layers of the network with Conv and Conv_Res modules, in order to enhance the computational efficiency. The optimization scheme was determined for the backbone network. Ablation experiments were conducted to verify the efficacy of the various improved modules. The refined YOLOv8n was achieved the superior accuracy and detection speed on the fragrant pear dataset, with a 0.4 and 0.5 percentage point increase in the F0.5 score and mean average precision, respectively, compared with the original YOLOv8n model. Detection speeds on GPU and CPU devices increased by 34.0% and 24.4%, respectively, indicating the rates of 99.4 and 15.3 frames per second, respectively. This high-precision and rapid detection can provide the valuable technical support to the real-time detection of fragrant pears in natural orchard environments. The improved model can also be expected to deploy into the fragrant pear picking robots. [ABSTRACT FROM AUTHOR]

Summary: Variation in anthocyanin biosynthesis in pear fruit provides genetic germplasm resources for breeding, while dwarfing is an important agronomic trait, which is beneficial to reduce the management costs and allow for the implementation of high‐density cultivation. Here, we combined bulked segregant analysis (BSA), quantitative trait loci (QTL), and structural variation (SV) analysis to identify a 14‐bp deletion which caused a frame shift mutation and resulted in the premature translation termination of a B‐box (BBX) family of zinc transcription factor, PyBBX24, and its allelic variation termed PyBBX24ΔN14. PyBBX24ΔN14 overexpression promotes anthocyanin biosynthesis in pear, strawberry, Arabidopsis, tobacco, and tomato, while that of PyBBX24 did not. PyBBX24ΔN14 directly activates the transcription of PyUFGT and PyMYB10 through interaction with PyHY5. Moreover, stable overexpression of PyBBX24ΔN14 exhibits a dwarfing phenotype in Arabidopsis, tobacco, and tomato plants. PyBBX24ΔN14 can activate the expression of PyGA2ox8 via directly binding to its promoter, thereby deactivating bioactive GAs and reducing the plant height. However, the nuclear localization signal (NLS) and Valine‐Proline (VP) motifs in the C‐terminus of PyBBX24 reverse these effects. Interestingly, mutations leading to premature termination of PyBBX24 were also identified in red sports of un‐related European pear varieties. We conclude that mutations in PyBBX24 gene link both an increase in pigmentation and a decrease in plant height. [ABSTRACT FROM AUTHOR]

Ring rot, caused by Botryosphaeria dothidea, is an important fungal disease of pear fruit during postharvest storage. Melatonin, as a plant growth regulator, plays an important role in enhancing the stress resistance of pear fruits. It enhances the resistance of pear fruits to ring rot by enhancing their antioxidant capacity. However, the underlying mechanism remains unclear. In this study, we examined the effect of melatonin on the growth of B. dothidea. Results showed that melatonin did not limit the growth of B. dothidea during in vitro culture. However, metabolomics and transcriptomics analyses of 'Whangkeumbae' pear (Pyrus pyrifolia) revealed that melatonin increased the activity of antioxidant enzymes, including peroxidase (POD), superoxide dismutase (SOD), and polyphenol oxidase (PPO), in the fruit and activated the phenylpropanoid metabolic pathway to improve fruit resistance. Furthermore, melatonin treatment significantly increased the contents of jasmonic acid and phlorizin in pear fruit, both of which could improve disease resistance. Jasmonic acid regulates melatonin synthesis and can also promote phlorizin synthesis, ultimately improving the resistance of pear fruit to ring rot. In summary, the interaction between melatonin and jasmonic acid and phlorizin enhances the antioxidant defense response and phenylpropanoid metabolism pathway of pear fruit, thereby enhancing the resistance of pear fruit to ring rot disease. Our results provide new insights into the application of melatonin in the resistance to pear fruit ring rot. [ABSTRACT FROM AUTHOR]

Few studies have been reported on the effect of planting years on fruit quality and soil of pear trees. In this study, four planting years (T5, T20, T30, and T40) of Cuiguan pears were used to analyze fruit quality, rhizosphere soil enzymes, and microbial diversity of pear trees, and their correlations. The results showed that the content of sucrose, reducing sugar and ascorbic acid in Cuiguan Pear showed a tendency of increasing and then decreasing with the increase of planting years, in which the highest content was found in 20- and 30-year-old fruits, and the highest content of total acid was found in 5-year-old fruits. Rhizosphere soil enzyme activities varied with planting year, with the highest protease activity in 20-year-old soil, phosphatase and urease in 30-year-old soil, polyphenol oxidase in 5-year-old soil, and sucrase in 40-year-old soil. The microbial diversity index and the number of OTUs showed an increasing and decreasing trend with the increase of planting years. Among the top 11 bacteria in pear rhizosphere soil average relative abundance, with Bradyrhizobium decreasing in relative abundance at the peak pear fruiting stages (T20 and T30), while Acidothermus showed an increasing trend in relative abundance with increasing planting years. RDA analysis showed that there were differences in the microbial community structure of pear trees at different planting years, and that both sucrose and reducing sugar contents in pears were positively correlated with T20 and T30, ascorbic acid content was positively correlated with T40, whereas the total acid content was positively correlated with T5, and that T20 was positively correlated with soil protease and phosphate mono esterase activities, and that T30 was positively correlated with polyphenol oxidase and urease activities, whereas T40 was positively correlated with sucrase activity. In summary, with the increase of planting years, changes in soil microbial community structure and soil enzyme activity have a significant impact on pear quality formation, and the results of the study provide a theoretical basis for scientific management of pear orchards. [ABSTRACT FROM AUTHOR]

Background: The homodomain-leucine zipper (HD-Zip) is a conserved transcription factor family unique to plants that regulate multiple developmental processes including lignificaion. Stone cell content is a key determinant negatively affecting pear fruit quality, which causes a grainy texture of fruit flesh, because of the lignified cell walls. Results: In this study, a comprehensive bioinformatics analysis of HD-Zip genes in Chinese white pear (Pyrus bretschneideri) (PbHBs) was performed. Genome-wide identification of the PbHB gene family revealed 67 genes encoding PbHB proteins, which could be divided into four subgroups (I, II, III, and IV). For some members, similar intron/exon structural patterns support close evolutionary relationships within the same subgroup. The functions of each subgroup of the PbHB family were predicted through comparative analysis with the HB genes in Arabidopsis and other plants. Cis-element analysis indicated that PbHB genes might be involved in plant hormone signalling and external environmental responses, such as light, stress, and temperature. Furthermore, RNA-sequencing data and quantitative real-time PCR (RT-qPCR) verification revealed the regulatory roles of PbHB genes in pear stone cell formation. Further, co-expression network analysis revealed that the eight PbHB genes could be classified into different clusters of co-expression with lignin-related genes. Besides, the biological function of PbHB24 in promoting stone cell formation has been demonstrated by overexpression in fruitlets. Conclusions: This study provided the comprehensive analysis of PbHBs and highlighted the importance of PbHB24 during stone cell development in pear fruits. [ABSTRACT FROM AUTHOR]

Türkiye is a prominent contributor to pear and diverse pome fruit production. Pear fruit with unusual brown to black spots and rot symptoms observed in public marketplaces in Mardin province have raised concerns regarding postharvest fruit health. The consistent isolation of a fungus from these fruits revealed morphological features indicative of Neoscytalidium dimidiatum. Phylogenetic confirmation of its identity ensued through BLASTn searches targeting, the internal transcribed spacer (ITS) of ribosomal DNA, the partial translation elongation factor 1‐alpha gene (tef1), and the partial β‐tubulin gene (tub2). Pathogenicity evaluations were conducted on common pome fruits, namely pears, apples, and quinces, unveiling the susceptibility of all examined fruits to postharvest infection by this emergent pathogen. Furthermore, an investigation was carried out to discern the pathogen's response to varying temperature ranges on pear fruits, revealing that the most pronounced lesions occurred at 30°C, followed by 25°C, 35°C, and 20°C. Conversely, no lesion development was observed at 10°C, 15°C, or 40°C. To the best of our knowledge, this study represents the first report of N. dimidiatum as the etiological agent responsible for postharvest rot in pear fruit. The implications of these findings highlight the potential threat posed by this pathogen to pome fruits postharvest, especially in regions where cold storage facilities are not widely utilized, warranting increased vigilance and preventive measures. [ABSTRACT FROM AUTHOR]

The ancient Chinese medical book "Compendium of Materia Medica" records that pears can relieve symptoms of respiratory-related diseases. Previous research has shown that pear Pyrus Pyrifolia (Burm.f.) Nakai has antioxidant and anti-inflammatory properties. However, the anti-inflammatory, antioxidant, and anti-photoaging protective effects of Pyrus pyrifolia (Burm.f.) Nakai seed components have not been studied. Ultraviolet light (UV) causes skin inflammation, damages the skin barrier, and is an important cause of skin photoaging. Therefore, UV light with a wavelength of 365 nm was used to irradiate HaCaT and mice. Western blot, real-time quantitative polymerase chain reaction, and fluorescence imaging system were used to explore its anti-UVA mechanism. Dialysis membrane and nuclear magnetic resonance were used for the chemical constituent analysis of pear seed water extract (PSWE). We found that PSWE can significantly reduce UVA-induced skin cell death and mitogen-activated protein kinase phosphorylation and can inhibit the mRNA expression of UVA-induced cytokines (including IL-1β, IL-6, and TNF-α). In addition, PSWE can also reduce the generation of oxidative stress within skin cells. In vivo experimental studies found that PSWE pretreatment effectively reduced transepidermal water loss, inflammation, redness, and dryness in hairless mice. The molecular weight of the active part of pear water extract is approximately 384. Based on the above results, we first found that pear seeds can effectively inhibit oxidative stress and damage caused by UVA. It is a natural extract with antioxidant properties and anti-aging activity that protects skin cells and strengthens the skin barrier. [ABSTRACT FROM AUTHOR]

DNA marker technology, being an alternative to classical hybrid selection approach, is a rapid method for identifying genes and loci associated with breeding-important traits at the early stages of ontogenesis, and, consequently, represents an approach for intensifying the breeding process. This review presents an overview of the studies on the identification of the economically important traits in the pear genome, as well as the development and use of marker-assisted selection (MAS) techniques. To date, a number of genetic factors have been identified in the pear genome, including the resistance to diseases and pests, namely, the resistance to European pear scab (V. pirina Aderh) and Asian pear scab (V. nashicola), to black spot (Alternaria alternata (Fr.) Keissler) and brown spot (Stemphylium vesicarium) disease, fire blight (Erwinia amylovora), pear psylla (Cacopsylla pyri), pear slug (Caliroacerasi), pear blister mite (Eriophyes pyri), self-incompatibility locus, and dwarf trait gene. Major genes and quantitative trait loci (QTLs) for the fruit quality characteristics have also been identified, namely those controlling fruit skin color and fruit russeting, fruit size and weight, taste, the level of ethylene production, and harvest time. It should be noted that Russian studies in this field are limited to the validation and use of MAS techniques developed abroad. According to the experience of Japanese researchers, the use of MAS for several key traits had considerably increased the efficiency of breeding process. Despite the currently limited list of MAS techniques for pears, the high pace of genome research guarantees fairly rapid development of new methods in the future. In combination with new breeding technologies (NBT), the use of MAS for pear is a promising trend in breeding. [ABSTRACT FROM AUTHOR]

Small secreted peptides (SSPs) play important roles in regulating plants' growth and development in response to external stimulus, but the genes and functions of SSPs in many species are still unknown. Therefore, it is particularly significant to characterize and annotate SSP genes in plant genomes. As a widely used stock of pears, Pyrus betulifolia has strong resistance to biotic and abiotic stresses. In this study, we analyzed the SSPs genes in the genome of P. betulifolia according to their characteristics and homology. A total of 1195 SSP genes were identified, and most of them are signaling molecules. Among these, we identified a new SSP, subtilase peptide 3 (SUBPEP3), which derived from the PA region of preSUBPEP3, increasing the expression level under salt stress. Both adding synthetic peptide SUBPEP3 to the culture medium of pears and the overexpression of SUBPEP3 in tobacco can improve the salt tolerance of plants. In summary, we annotated the SSP genes in the P. betulifolia genome and identified a small secreted peptide SUBPEP3 that regulates the salt tolerance of P. betulifolia, which provides an important theoretical basis for further revealing the function of SSPs. [ABSTRACT FROM AUTHOR]

As a cell proliferation regulator involved in wide biological processes in plants, GRF-INTERACTING FACTOR (GIF) controls different tissues development. However, whether GIF participates in fruit development remains unclear. According to transcriptome data, we identified PbGIF1 was highly expressed during fruit development in cytokinins induced parthenocarpy pear. In the present study, the biofunction of PbGIF1 was initially verified. Overexpression of PbGIF1 promoted fruit size of transgenic tomato. The size of flesh fruit was not affected by cell expansion but the cell proliferation was promoted by overexpressing PbGIF1. The accelerated cell proliferation process was also observed in PbGIF1-overexpressed transgenic pear fruit calli. The transcriptional regulation of cytokinins on PbGIF1 was further confirmed by exogenous CPPU treatments in pear fruitlets. To investigate the underlying mechanism, the cytokinins-responded factor, PbRR1, was further focused on. The results of Yeast-one-hybrid assay suggested that PbRR1 can bind to the promoter sequence of PbGIF1. The transcriptional activation of PbRR1 on PbGIF1 was also confirmed by Dual-Luciferase assays. Taken together, the results showed that cytokinins control pear fruit development via the transcriptional activation of PbGIF1 by PbRR1. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) and salicylic acid (SA) are essential signaling molecules in plant cells that participate in responses to biotic and abiotic stresses. Changes in ROS and SA signals during interactions between pear and the pear scab pathogen Venturia nashicola remain unclear. Herein, we analyzed the roles of ROS in the signal transduction pathway of pear scab resistance using the highly resistant Huangguan and susceptible Xuehua cultivars of pear (Pyrus bretschneideri Rehd). Protoplasts, calluses, and leaves were obtained from 14-year-old pear trees and treated with V. nashicola for different periods. The results showed that ROS rapidly accumulated in protoplasts of both cultivars within a 120-min treatment period, but the fluorescence intensity of ROS differed between cultivars. The H2O2 content in fruit-derived calluses of Huangguan peaked at 48 h post-infection at levels 1.85 times higher than those in Xuehua. Induction of H2O2 by V. nashicola in Huangguan was more intense than in Xuehua over a 96-h treatment period. At 96 h post-infection, the malondialdehyde content in leaves of Huangguan was significantly lower than in Xuehua, while the activities of superoxide dismutase, peroxidase, and catalase, and the relative expression levels of PbMnSOD, PbPOD, and PbCAT genes were higher in Huangguan than Xuehua. V. nashicola infection also caused a continuous increase in the leaf SA content of Huangguan, which was 6.76 times higher than in Xuehua at 96 h post-infection, and V. nashicola exposure upregulated the expression of PbPAL, PbICS, PbPR1, and PbPR5. In summary, both ROS and SA participated in the responses of pear trees to V. nashicola infection and played vital roles in the signal transduction pathway of pear scab resistance. [ABSTRACT FROM AUTHOR]

Summary: Abiotic stresses have had a substantial impact on fruit crop output and quality. Plants have evolved an efficient immune system to combat abiotic stress, which employs reactive oxygen species (ROS) to activate the downstream defence response signals. Although an aquaporin protein encoded by PbPIP1;4 is identified from transcriptome analysis of Pyrus betulaefolia plants under drought treatments, little attention has been paid to the role of PIP and ROS in responding to abiotic stresses in pear plants. In this study, we discovered that overexpression of PbPIP1;4 in pear callus improved tolerance to oxidative and osmotic stresses by reconstructing redox homeostasis and ABA signal pathways. PbPIP1;4 overexpression enhanced the transport of H2O2 into pear and yeast cells. Overexpression of PbPIP1;4 in Arabidopsis plants mitigates the stress effects caused by adding ABA, including stomatal closure and reduction of seed germination and seedling growth. Overexpression of PbPIP1;4 in Arabidopsis plants decreases drought‐induced leaf withering. The PbPIP1;4 promoter could be bound and activated by TF PbHsfC1a. Overexpression of PbHsfC1a in Arabidopsis plants rescued the leaf from wilting under drought stress. PbHsfC1a could bind to and activate AtNCED4 and PbNCED4 promoters, but the activation could be inhibited by adding ABA. Besides, PbNCED expression was up‐regulated under H2O2 treatment but down‐regulated under ABA treatment. In conclusion, this study revealed that PbHsfC1a is a positive regulator of abiotic stress, by targeting PbPIP1;4 and PbNCED4 promoters and activating their expression to mediate redox homeostasis and ABA biosynthesis. It provides valuable information for breeding drought‐resistant pear cultivars through gene modification. [ABSTRACT FROM AUTHOR]

Four poems by Claude Wilkinson are presented "Nightfall" First Line: When as much, Last Line: the velvet hours., "Our Pear Tree" First Line: If Eden's tree of life wasn't destroyed, Last Line: after summer, it was still bearing beautiful fruit., "Providence" First Line: Being the son of even, Last Line: and crowned with thorns., "Repast" First Line: As for both wake, Last Line: has slipped past your lips.

Increased food, feed, and biofuel demands of the future will require a greater reliance upon crop production systems in arid and semi‐arid regions around the world. Diminishing freshwater resources and hotter and drier climatic conditions will also necessitate the use of highly drought tolerant and water‐use efficient crops. Cactus pear (Opuntia ficus‐indica) is a low‐water input, climate‐resilient crop capable of high biomass production due to its use of crassulacean acid metabolism (CAM). Cactus pear produces both food and forage/fodder, a wide variety of high‐value byproducts, and serves as a bioenergy feedstock for biogas or bioethanol production. Here, we evaluated the biomass productivity of 14 Opuntia spp. accessions from the National Arid Land Plant Genetic Resources Unit (NALPGRU) in Parlier, CA under semi‐arid conditions with a planting density of 6667 plants ha−1 over a 3‐year period to identify high‐yielding biomass producers. Mean annual cladode fresh weight (CFW) (73.7 Mg ha−1 year−1), cladode dry weight (CDW) (5.2 Mg ha−1 year−1), and cladode count (CC) (10.5 cladodes plant−1) increased by 2.9‐, 2.8‐, and 2.8‐fold in year 3 compared with year 1. PARL 845, hybrid no. 46 (O. ficus‐indica × O. lindheimerii), showed the highest annual mean CFW (152.8 Mg ha−1 year−1), CDW (13.3 Mg ha−1 year−1), CC (22.1 cladodes plant−1), and dry matter content (DMC, 11.2%) among all accessions tested. Non‐hybrid accessions PARL 242 (O. cochenillifera), PARL 582 (Opuntia sp.), and PARL 584 (Opuntia sp.) showed 100% cladode establishment rates and CDW productivity of >6 Mg ha−1 year−1. Such biomass productivity results indicate that cactus pear displays great potential as a crop with many uses with lower water inputs than conventional crops for arid and semi‐arid environments. [ABSTRACT FROM AUTHOR]

Background and Aims The softening of ripening fruit involves partial depolymerization of cell-wall pectin by three types of reaction: enzymic hydrolysis, enzymic elimination (lyase-catalysed) and non-enzymic oxidative scission. Two known lyase activities are pectate lyase and rhamnogalacturonan lyase (RGL), potentially causing mid-chain cleavage of homogalacturonan and rhamnogalacturonan-I (RG-I) domains of pectin respectively. However, the important biological question of whether RGL exhibits action in vivo had not been tested. Methods We developed a method for specifically and sensitively detecting in-vivo RGL products, based on Driselase digestion of cell walls and detection of a characteristic unsaturated 'fingerprint' product (tetrasaccharide) of RGL action. Key Results In model experiments, potato RG-I that had been partially cleaved in vitro by commercial RGL was digested by Driselase, releasing an unsaturated tetrasaccharide ('ΔUA-Rha-GalA-Rha'), taken as diagnostic of RGL action. This highly acidic fingerprint compound was separated from monosaccharides (galacturonate, galactose, rhamnose, etc.) by electrophoresis at pH 2, then separated from ΔUA-GalA (the fingerprint of pectate lyase action) by thin-layer chromatography. The 'ΔUA-Rha-GalA-Rha' was confirmed as 4-deoxy-β- l - threo -hex-4-enopyranuronosyl-(1→2)- l -rhamnosyl-(1→4)- d -galacturonosyl-(1→2)- l -rhamnose by mass spectrometry and acid hydrolysis. Driselase digestion of cell walls from diverse ripe fruits [date, sea buckthorn, cranberry, yew (arils), mango, plum, blackberry, apple, pear and strawberry] yielded the same fingerprint compound, demonstrating that RGL had been acting in vivo in these fruits prior to harvest. The 'fingerprint' : (galacturonate + rhamnose) ratio in digests from ripe dates was approximately 1 : 72 (mol/mol), indicating that ~1.4 % of the backbone Rha→GalA bonds in endogenous RG-I had been cleaved by in-vivo RGL action. Conclusions The results provide the first demonstration that RGL, previously known from studies of fruit gene expression, proteomic studies and in-vitro enzyme activity, exhibits enzyme action in the walls of soft fruits and may thus be proposed to contribute to fruit softening. [ABSTRACT FROM AUTHOR]

Summary: The present study aimed to evaluate the combined application of edible coatings (alginate or pectin) and the osmotic dehydration process (glucose solution at 40 °Brix and 60 °Brix, solution temperatures of 20 and 40 °C, and process times of 1, 2, 4, 8, and 16 h) on mass transfer kinetics and physicochemical parameters (weight reduction (WR), water loss (WL), solids gain (SG), and optical and mechanical properties) of pear cubes. The best dehydration performance was observed in the coated samples treated at 60 °Brix‐40 °C. At the end of this process, the coated samples showed higher values of WR (77.30% and 75.13%) and WL (77.39%; 74.38%) and lower values of SG (1.69% and 1.24%) than the uncoated samples (WR: 65.97%, WL: 68.38%, and SG: 4.12%). Additionally, optimal retention of optical and mechanical properties was achieved in the coated samples exposed to the 40 °Brix‐40 °C condition. [ABSTRACT FROM AUTHOR]

Simple Summary: Bumblebees are well-suited pollinators of economic crops. This study evaluated the foraging behavior and pollination effects of Bombus terrestris on cherry tomatoes and pears in northern China. B. terrestris pollination can improve cultivation efficiency, increase yield, and produce more economic benefits, which indicates that it has great potential in pollination applications for cherry tomatoes and pears in northern China. Bumblebees (Bombus terrestris) have strong environmental adaptability and high pollen transfer efficiency, making them well-suited pollinators of economic crops. However, bumblebee pollination is still not widely applied in northern China due to the lack of data on foraging behavior and pollination effects. We conducted a three-year experiment involving cherry tomatoes (Solanum lycopersicum L.) and pears (Pyrus spp.) treated with bumblebee pollination to evaluate the foraging behavior and pollination effects on these two crops. Results showed that B. terrestris had enhanced foraging activities as daytime temperatures rose from 18 °C to 26 °C, as indicated by the increased number of bees leaving the hive and returning bees carrying pollen in greenhouses in winter. There were two peaks in the foraging activity of bumblebees in pear orchards in early spring, which was closely related to the temperature change in the daytime. Undoubtedly, cherry tomatoes treated with B. terrestris had higher fruit setting rate, weight, seed number, and fruit yields compared to those with hormone 2,4-dichlorophenoxyacetic acid treatments, as well as a lower rate of deformed fruits. B. terrestris pollination can significantly increase the fruit setting rate and fruit yield of pears, compared with open pollination, and can fully achieve the effect of hand pollination. B. terrestris pollination can improve cultivation efficiency, increase yield, and produce more economic benefits. Moreover, it can also contribute to reducing hormone residues and ensure the safety of agricultural products. We recommend its application to cherry tomatoes in greenhouses in winter and potential application to pears in orchards in early spring in northern China. However, the risk to local bumblebee species of introducing commercially available bumblebees into orchards should be considered and evaluated in future research. This study provides both empirical support and a theoretical basis for the selection of bumblebees as pollinators in the production of economically important crops and the improvement of crop cultivation management in northern China. [ABSTRACT FROM AUTHOR]

The accessible literature covered in this paper commonly highlights psyllids as a significant group of insects affecting pear trees, posing a continual challenge for commercial orchards. With the development of modern pear cultivation systems, Cacopsylla pyri Linnaeus 1758 (Hemiptera: Psyllidae) has emerged as a major pest in pear orchards across many European countries, including those in the Western Balkans. For years, the agricultural sector has primarily relied on chemical insecticides to control pear psyllas, but these methods often fail to produce satisfactory results. This is largely due to C. pyri's rapid development of resistance to chemical treatments. Consequently, modern agriculture is increasingly shifting towards biological methods to manage C. pyri, involving the identification and conservation of its natural enemies. Although there is an abundance of research on the natural predators of C. pyri and their biocontrol applications across the globe, the Western Balkan region has conducted relatively few studies on the subject. Globally, various parasitoids, predators, and entomopathogenic fungi are often cited as effective against C. pyri. Specific species registered in the agroecological conditions of the Western Balkans include parasitic wasps such as Trechnites insidiosus Crawford, 1910 (Hymenoptera: Encyrtidae) and Prionomitus mitratus Dalman, 1820 (Hymenoptera: Encyrtidae), as well as the predatory bug Anthocoris nemoralis Fabricius, 1794 (Hemiptera: Anthocoridae). However, most Balkan countries have yet to fully utilise the potential of beneficial entomofauna or develop strategies for their commercial application at a national level. Considering that C. pyri is a major pest in pear cultivation and its natural enemies have not been thoroughly explored in most of the Western Balkans, this paper aims to review the literature data on available natural enemies of pear psyllas and to highlight and promote their undeniable potential in biological control. [ABSTRACT FROM AUTHOR]

The purpose of this research was to examine the viability of applying a flawless polyaniline coating on steel spearheads to preserve them and protect them from corrosion. The spearpoints, thought to be archaeologically significant, were acquired from the Military Museum in Al-Qala, Egypt. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy were used to characterize the spearheads chemical composition and microstructure (EDX). The spearheads were determined to be constructed of steel and to have a coating of ferric oxide and other corrosion products on their exteriors. After that, a flawless polyaniline coating was electrochemically deposited onto the spearpoints in a way that was both quick and cheap. Many types of corrosion tests, such as electrochemical impedance spectroscopy and potentiodynamic polarization (PDP) readings, were used to determine the coating's effectiveness. The steel spearheads' findings revealed a significant improvement in their resistance to corrosion after being coated with flawless polyaniline. The coating served as a barrier, blocking out water and other corrosive substances and slowing the buildup of corrosion byproducts on the spearpoints. In conclusion, our research shows that a flawless polyaniline coating may be an effective anti-corrosion treatment for ancient steel artifacts. The approach is straightforward, cheap, and readily scalable for massive conservation efforts. [ABSTRACT FROM AUTHOR]

Background: Plant diseases caused by pathogenic fungi are devastating. However, commonly used fungicides are harmful to the environment, and some are becoming ineffective due to fungal resistance. Therefore, eco-friendly biological methods to control pathogenic fungi are urgently needed. Results: In this study, a strain, Paenibacillus sp. lzh-N1, that could inhibit the growth of the pathogenic fungus Mycosphaerella sentina (Fr) Schrorter was isolated from the rhizosphere soil of pear trees, and the complete genome sequence of the strain was obtained, annotated, and analyzed to reveal the genetic foundation of its antagonistic ability. The entire genome of this strain contained a circular chromosome of 5,641,488 bp with a GC content of 45.50%. The results of species identification show that the strain belongs to the same species as P. polymyxa Sb3-1 and P. polymyxa CJX518. Sixteen secondary metabolic biosynthetic gene clusters were predicted by antiSMASH, including those of the antifungal peptides fusaricidin B and paenilarvins. In addition, biofilm formation-related genes containing two potential gene clusters for cyclic lactone autoinducer, a gene encoding S-ribosylhomocysteine lyase (LuxS), and three genes encoding exopolysaccharide biosynthesis protein were identified. Conclusions: Antifungal peptides and glucanase biosynthesized by Paenibacillus sp. lzh-N1 may be responsible for its antagonistic effect. Moreover, quorum sensing systems may influence the biocontrol activity of this strain directly or indirectly. [ABSTRACT FROM AUTHOR]

Background: Dwarf rootstocks have important practical significance for high-density planting in pear orchards. The shoots of 'Cuiguan' grafted onto the dwarf rootstock were shorter than those grafted onto the vigorous rootstock. However, the mechanism of shorter shoot formation is not clear. Results: In this study, the current-year shoot transcriptomes and phytohormone contents of 'CG‒QA' ('Cuiguan' was grafted onto 'Quince A', and 'Hardy' was used as interstock) and 'CG‒DL' ('Cuiguan' was grafted onto 'Duli', and 'Hardy' was used as interstock) were compared. The transcriptome results showed that a total of 452 differentially expressed genes (DEGs) were identified, including 248 downregulated genes and 204 upregulated genes; the plant hormone signal transduction and zeatin biosynthesis pathways were significantly enriched in the top 20 KEGG enrichment terms. Abscisic acid (ABA) was the most abundant hormone in 'CG‒QA' and 'CG‒DL'; auxin and cytokinin (CTK) were the most diverse hormones; additionally, the contents of ABA, auxin, and CTK in 'CG‒DL' were higher than those in 'CG‒QA', while the fresh shoot of 'CG‒QA' accumulated more gibberellin (GA) and salicylic acid (SA). Metabolome and transcriptome co-analysis identified three key hormone-related DEGs, of which two (Aldehyde dehydrogenase gene ALDH3F1 and YUCCA2) were upregulated and one (Cytokinin oxidase/dehydrogenase gene CKX3) was downregulated. Conclusions: Based on the results of transcriptomic and metabolomic analysis, we found that auxin and CTK mainly regulated the shoot differences of 'CG–QA' and 'CG–DL', and other hormones such as ABA, GA, and SA synergistically regulated this process. Three hormone-related genes ALDH3F1, YUCCA2, and CKX3 were the key genes contributing to the difference in shoot growth between 'CG–QA' and 'CG–DL' pear. This research provides new insight into the molecular mechanism underlying shoot shortening after grafted onto dwarf rootstocks. [ABSTRACT FROM AUTHOR]

Background: Chlorophyll (Chl) is an agronomic trait associated with photosynthesis and yield. Gibberellin 2-oxidases (GA2oxs) have previously been shown to be involved in Chl accumulation. However, whether and how the PbrGA2ox proteins (PbrGA2oxs) mediate Chl accumulation in pear (Pyrus spp.) is scarce. Results: Here, we aimed to elucidate the role of the pear GA2ox gene family in Chl accumulation and the related underlying mechanisms. We isolated 13 PbrGA2ox genes (PbrGA2oxs) from the pear database and identified PbrGA2ox1 as a potential regulator of Chl accumulation. We found that transiently overexpressing PbrGA2ox1 in chlorotic pear leaves led to Chl accumulation, and PbrGA2ox1 silencing in normal pear leaves led to Chl degradation, as evident by the regreening and chlorosis phenomenon, respectively. Meanwhile, PbrGA2ox1-overexpressing (OE) tobacco plants discernably exhibited Chl built-up, as evidenced by significantly higher Pn and Fv/Fm. In addition, RNA sequencing (RNA-seq), physiological and biochemical investigations revealed an increase in abscisic acid (ABA), methyl jasmonate (MeJA), and salicylic acid (SA) concentrations and signaling pathways; a marked elevation in reducing and soluble sugar contents; and a marginal decline in the starch and sucrose levels in OE plants. Interestingly, PbrGA2ox1 overexpression did not prominently affect Chl synthesis. However, it indeed facilitated chloroplast development by increasing chloroplast number per cell and compacting the thylakoid granum stacks. These findings might jointly contribute to Chl accumulation in OE plants. Conclusion: Overall, our results suggested that GA2oxs accelerate Chl accumulation by stimulating chloroplast development and proved the potential of PbrGA2ox1 as a candidate gene for genetically breeding biofortified pear plants with a higher yield. [ABSTRACT FROM AUTHOR]

Cultivated pear consists of several Pyrus species with Pyrus communis (European pear) representing a large fraction of worldwide production. As a relatively recently domesticated crop and perennial tree, pear can benefit from genome-assisted breeding. Additionally, comparative genomics within Rosaceae promises greater understanding of evolution within this economically important family. Here, we generate a fully phased chromosome-scale genome assembly of P. communis 'd'Anjou.' Using PacBio HiFi and Dovetail Omni-C reads, the genome is resolved into the expected 17 chromosomes, with each haplotype totaling nearly 540 Megabases and a contig N50 of nearly 14 Mb. Both haplotypes are highly syntenic to each other and to the Malus domestica 'Honeycrisp' apple genome. Nearly 45,000 genes were annotated in each haplotype, over 90% of which have direct RNA-seq expression evidence. We detect signatures of the known whole-genome duplication shared between apple and pear, and we estimate 57% of d'Anjou genes are retained in duplicate derived from this event. This genome highlights the value of generating phased diploid assemblies for recovering the full allelic complement in highly heterozygous crop species. [ABSTRACT FROM AUTHOR]

Fruit mass and sugar content are important quality attributes of apple and pear fruit. During fruit growth, water and sugars accumulate as a result of the coordination of water and solid fluxes. This causes expansive growth driven by turgor pressure and controlled by cell mechanical properties. To analyse the effect of environmental conditions on fruit growth dynamics, a biophysical model of apple (Malus domestica Borkh.) and pear (Pyrus communis L.) fruit growth was developed and adapted from the Fishman-Génard model. Dynamically changing patterns of average fruit fresh mass, dry mass and soluble solid mass in response to the environmental conditions during multiple seasons of varying environmental conditions were well captured by a parameterised model for apple and pear fruit growth. Sensitivity analyses showed that the model was most sensitive to variations in parameters related to active transport, cell wall extensibility and plant water status. The model enabled the analysis of how fruit growth dynamics were affected by stress conditions. This model, which integrates biophysical laws and parameters governing fruit water and solute dynamics, may serve as a basis to investigate the role of the processes involved in the complex growing behavior of pome fruit, and to optimise and predict fruit growth and quality. • Apple and pear fruit growth were modeled with balance and biophysical equations. • Seasonal dynamics of fruit fresh, dry and soluble solid mass were simulated. • Model sensitivity was highest for active transport and plant water status. • Stress conditions affected fruit growth dynamics and transport processes. [ABSTRACT FROM AUTHOR]

Cold stress is a significant abiotic stress that profoundly impacts the quality of fruits and vegetables. This study parsed the effects of fermentation supernatant (CFS-R1) and bacterial suspension (CRS-R1) of antagonistic bacteria R1 on the physiological quality and sugar metabolism of 'Nanguo' pears under chilling stress. The results demonstrated that both CFS-R1 and CRS-R1 significantly reduced the browning and weight loss of the fruit and suppressed the chilling injury. The relative electrolyte leakage of CFS-R1 and CRS-R1 treated fruits were reduced by 9.4 % and 9.9 % respectively on day 7 of storage, indicating improved cell membrane stability. Furthermore, both CFS-R1 and CRS-R1 maintained the sucrose content of the fruits, with CFS-R1 also increasing the content of glucose and fructose. In conclusion, the antagonist R1 can serve as a biological preservative to enhance the cold tolerance of Nanguo pear fruit by regulating sugar metabolism. [ABSTRACT FROM AUTHOR]

SMXL genes constitute a conserved gene family that is ubiquitous in angiosperms and involved in regulating various plant processes, including branching, leaf elongation, and anthocyanin biosynthesis, but little is known about their molecular functions in pear branching. Here, we performed genome-wide identification and investigation of the SMXL genes in 16 angiosperms and analyzed their phylogenetics, structural features, conserved motifs, and expression patterns. In total, 121 SMXLs genes were identified and were classified into four groups. The number of non-redundant SMXL genes in each species varied from 3 (Amborella trichopoda Baill.) to 18 (Glycine max Merr.) and revealed clear gene expansion events over evolutionary history. All the SMXL genes showed conserved structures, containing no more than two introns. Three-dimensional protein structure prediction revealed distinct structures between but similar structures within groups. A quantitative real-time PCR analysis revealed different expressions of 10 SMXL genes from pear branching induced by fruit-thinning treatment. Overall, our study provides a comprehensive investigation of SMXL genes in the Rosaceae family, especially pear. The results offer a reference for understanding the evolutionary history of SMXL genes and provide excellent candidates for studying fruit tree branching regulation, and in facilitating pear pruning and planting strategies. [ABSTRACT FROM AUTHOR]

Work on large samples of southern African archaeological lithics, probably used to tip hunting weapons amongst other things, and ethno-historical bone and iron weapon tips of known use exposed limitations in the tip cross-sectional area (TCSA) method's robustness for hypothesising about variation in ancient weapon-delivery systems. Here, we list some of the limitations and discuss a few recently published improvements in tip cross-sectional area ranges and data presentation. Our main contribution is the meaningful enlargement of datasets obtained from hafted weapon tips and/or weapon tips of known use mostly from sub-Saharan Africa. We briefly discuss why this region is relevant for studying trends in the evolution and development of hunting weapons. Our new data are used to strengthen and constrain the different TCSA ranges used as proxies for poisoned arrow tips, un-poisoned arrow tips, javelin tips, stabbing-spear tips, and to suggest a working TCSA range for thrusting-spear tips. We demonstrate that the calibrated TCSA ranges have robust statistical integrity as proxies for the different weapon-delivery systems they represent. Apart from the dart-tip category, the TCSA method has now been improved to accommodate more nuanced and accurate interpretations, while further strengthening hypothesis building about ancient weapon systems. [ABSTRACT FROM AUTHOR]

Fruitlet calyx shedding in pear plants is apparently regulated via numerous pathways that involve both environmental triggers and phytohormones cues such as auxin. In this study, we found at 10 days after full bloom (DAFB) higher levels of indoleacetic acid (IAA) and tryptophan (Trp) in calyx persistence fruitlet (CPF) than calyx shedding fruitlet (CSF) of 'Danshan Suli' pear (Pyrus bretschneideri Rhed.). Consisting with this, the activity of indolealdehyde oxidase (IAAIdO), which promotes IAA synthesis, was remarkably increased, and that of peroxidase (POD), which degrades IAA, dropped markedly in CPF but not in CSF. Further, qRT-PCR results revealed that most of 31 PbrARFs (encoding auxin response factors) in Pyrus bretschneideri were highly expressed in CPF, whereas PbrARF4, PbrARF24 and PbrARF26 were significantly downregulated in CPF vis-a-vis CSF. Phylogenetic analysis revealed that 6 PbrARFs clustered in the group III, where PbrARF4 showed the closest affinity with AtARF1 that promotes organ abscission, indicating a putative role of PbrARF4 in mediating the process of calyx shedding in pear. In fact, the ectopic overexpression of PbrARF4 in Solanum lycopersicum resulted in an earlier-formed and deeper abscission layer (AL) in the transgenic plants, whose calyxes were more prone to wilt at the mature red stage (MR) compared with the control plants (wild-type). More importantly, expression levels of the abscission genes SlLS and SlCel2 in transgenic plants overexpressing PbrARF4 were significantly upregulated in comparation with the WT, whereas those of SlBI and SlTAPG2 were considerably inhibited. Further, PbrJOINTLESS and PbrIDA, the two genes related to calyx shedding in pear, were up-regulated more in CSF than CPF. The findings contribute to a better understanding of PbrARFs involved in fruitlet calyx shedding of pear, which could prove beneficial to improving the quality of pear fruit. [ABSTRACT FROM AUTHOR]

The pear is an economic fruit that is widely planted around the world and is loved by people for its rich nutritional value. Autophagy is a self-protection mechanism in eukaryotes, and its occurrence often accompanied by the degradation of damaged substances in cells and the recycling of nutrients. Autophagy is one of the mechanisms through which plants respond to environmental stress and plays an important role in plant development and stress resistance. Functional studies of autophagy-related genes (ATGs) have been performed on a variety of plant species, but little information is available on the ATG family in pear (Pyrus bretschneideri Rehd). Therefore, we analyzed the evolutionary dynamics and performed a genome-wide characterization of the PbrATG gene family. A total of 28 PbrATG members were identified. Phylogenetic analysis showed that PbrATGs were more closely related to ATGs of European pear and apple. Evolutionary analysis revealed that whole-genome duplication (WGD) and dispersed duplication events were the main driving forces of PbrATG family expansion. Expression analysis of different pear tissues showed that all the genes were expressed in different pear tissues, and different PbrATGs are expressed at different times and in different locations. Moreover, all PbrATGs also responded to different abiotic stresses, especially salt and drought stress, which elicited the highest expression levels. Pear seedlings were subsequently infected with Botryosphaeria dothidea (B. dothidea). The results showed that different PbrATGs had different expression patterns at different infection stages. According to the gene expression data, PbrATG1a was selected as a key autophagy gene for further analysis. Silencing of PbrATG1a reduced the resistance of pear to B. dothidea, which resulted in increased lesions, reactive oxygen species (ROS) contents, antioxidant enzyme activity, and gene expression levels in the silenced pear seedlings after B. dothidea inoculation. In this study, a comprehensive bioinformatic analysis of ATGs was conducted, and the functions of PbrATGs in pear development and in response to stress were elucidated, which laid a foundation for further study of the molecular mechanism of autophagy and a new strategy for pear resistance breeding. [ABSTRACT FROM AUTHOR]

Genomic selection (GS) has the potential to improve selection efficiency and shorten the breeding cycle in fruit tree breeding. In this study, we evaluated the effect of prediction methods, marker density and the training population (TP) size on pear GS for improving its performance and reducing cost. We evaluated GS under two scenarios: (1) five-fold cross-validation in an interspecific pear family; (2) independent validation. Based on the cross-validation scheme, the prediction accuracy (PA) of eight fruit traits varied between 0.33 (fruit core vertical diameter) and 0.65 (stone cell content). Except for single fruit weight, a slightly better prediction accuracy (PA) was observed for the five parametrical methods compared with the two non-parametrical methods. In our TP of 310 individuals, 2 000 single nucleotide polymorphism (SNP) markers were sufficient to make reasonably accurate predictions. PAs for different traits increased by 18.21%e46.98% when the TP size increased from 50 to 100, but the increment was smaller (-4.13%e33.91%) when the TP size increased from 200 to 250. For independent validation, the PAs ranged from 0.11 to 0.45 using rrBLUP method. In summary, our results showed that the TP size and SNP numbers had a greater impact on the PA than prediction methods. Furthermore, relatedness among the training and validation sets, and the complexity of traits should be considered when designing a TP to predict the test panel. [ABSTRACT FROM AUTHOR]

This study was carried out between 2020 and 2021 on local pear genotypes grown in the Malatya region (Türkiye), especially in the yard of Apple-Pear Germplasm of Malatya Turgut Özal University. In the study, phenological, pomological, and phytochemical characteristics of nine pear genotypes were analyzed. The following dates were identified for the selected characteristics: the bud swell between March 9 and 27, the bud bursts between March 14 and April 1, the start of flowering between March 28 and April 7, full bloom between April 2 and 11, the end of flowering between April 6 and 15, harvest between August 10 and November 13, defoliation between December 3 and 17, and the number of days from full bloom to harvest ranged between 128 and 216 days. The following results were obtained: fruit weights were 46.3-202.6 g, fruit lengths were 44.8-91.2 mm, fruit diameters were 43.8-76.2 mm, fruit flesh firmness were 2.4-9.62 kg/cm2, fruit volume was 45.5-204.3 ml, and fruit color values were 21.3-77.1 as L value, -2.49-0.1 as a value, and -2.03-54 as b value. The water-soluble dry matter content of the genotypes ranged between 10.3-15.9, pH values ranged between 3.99-5.37, total phenolic content ranged between 167-992 mg GAE/1000g, and total antioxidant activities ranged from 284 to 1454 mg TEAC/1000 g. Aliseydi from the summer pear genotypes and Parlak and Armut1 genotypes from the autumn genotypes were important. It is thought that Biber, Dudunun and Efendi genotypes from winter genotypes may be important materials for future studies. [ABSTRACT FROM AUTHOR]

As a common disease, canker seriously affects the yield and quality of fragrant pear due to the lack of effective control measures. Some fungi have been reported to harbor rich reservoirs of viral resources, and some mycoviruses can be used as biocontrol agents against plant diseases. In this study, 199 isolates were obtained from diseased branches of fragrant pear in the main production areas of Xinjiang. Among them, 134 belonged to Valsa spp., identified using morphological and molecular biological techniques, in which V. mali was the dominant species. The mycoviruses in Valsa spp. were further identified using metatranscriptomic sequencing and RT-PCR. The results revealed that a total of seven mycoviruses were identified, belonging to Botourmiaviridae, Endornaviridae, Fusariviridae, Hypoviridae, Mitoviridae, and Narnaviridae, among which Phomopsis longicolla hypovirus (PlHV) was dominant in all the sample collection regions. The Cryphonectria hypovirus 3-XJ1 (CHV3-XJ1), Botourmiaviridae sp.-XJ1 (BVsp-XJ1), and Fusariviridae sp.-XJ1 (Fvsp-XJ1) were new mycoviruses discovered within the Valsa spp. More importantly, compared with those in the virus-free Valsa spp. strain, the growth rate and virulence of the VN-5 strain co-infected with PlHV and CHV3-XJ1 were reduced by 59% and 75%, respectively, and the growth rate and virulence of the VN-34 strain infected with PlHV were reduced by 42% and 55%, respectively. On the other hand, the horizontal transmission efficiency of PlHV decreased when PlHV was co-infected with CHV3-XJ1, indicating that PlHV and CHV3-XJ1 were antagonistic. In summary, the mycoviruses in Valsa spp. were identified in Xinjiang for the first time, and three of them were newly discovered mycoviruses, with two strains yielding good results. These results will offer potential biocontrol resources for managing pear canker disease and provide a theoretical basis for the control of fruit tree Valsa canker disease. [ABSTRACT FROM AUTHOR]

Cold shock domain proteins (CSPs), initially identified in Escherichia coli, have been demonstrated to play a positive role in cold resistance. Previous studies in wheat, rice, and Arabidopsis have indicated the functional conservation of CSPs in cold resistance between bacteria and higher plants. However, the biological functions of PbrCSPs in pear pollen tubes, which represent the fragile reproductive organs highly sensitive to low temperature, remain largely unknown. In this study, a total of 22 CSPs were identified in the seven Rosaceae species, with a focus on characterizing four PbrCSPs in pear (Pyrus bretschneideri Rehder). All four PbrCSPs were structurally conserved and responsive to the abiotic stresses, such as cold, high osmotic, and abscisic acid (ABA) treatments. PbrCSP1, which is specifically expressed in pear pollen tubes, was selected for further research. PbrCSP1 was localized in both the cytoplasm and nucleus. Suppressing the expression of PbrCSP1 significantly inhibited the pollen tube growth in vitro. Conversely, overexpression of PbrCSP1 promoted the growth of pear pollen tubes under the normal condition and, notably, under the cold environment at 4 °C. These findings highlight an essential role of PbrCSP1 in facilitating the normal growth and enhancing cold resistance in pear pollen tubes. [ABSTRACT FROM AUTHOR]

Aims: At the same location, variability among orchards may be high, which is reflected in fruit quality, and it may be associated mainly with growers' practices. This study aimed to identify physicochemical variability within pears (Pyrus communis L. cv 'Rocha') from three orchards from the same location and under the same climate conditions and correlate it with mineral composition. Methods: Fruits from three orchards harvested at the optimal harvest time were characterized during ripening under shelf-life conditions of 7 d at 20 ± 2 °C. The analyses performed included ethylene production, respiration rate, fruit quality (firmness, skin colour, soluble solids, and titratable acidity), macro and micronutrients, ethylene biosynthesis enzymes, esters, sugars, and organic acids. Principal component analysis was used to show the variability among fruits from the three orchards and to correlate the differences with the fruit mineral composition. Results: Phosphorus (P) and potassium (K) were significantly correlated with esters and soluble solids content (r ∼ 0.4 for both minerals). Fruits with higher P and K concentrations were associated with a potential over-ripeness pattern considering their higher acetate production and lower sugar concentration. Esters, soluble sugars, and sorbitol were the dominant fruit quality factors responsible for the differences among the orchards. Conclusion: With this study it is expected that a better understanding of the relationship between specific minerals and quality parameters can help growers manage their orchards more efficiently and achieve consumers' quality demands. [ABSTRACT FROM AUTHOR]

Pears are abundant in bioactive compounds, which exert favorable effects on human health. The biophysical attributes of fruit cuticles are pivotal in determining fruit quality, storability, and susceptibility to mold growth. This study aimed to elucidate the biophysical properties of six pear cultivars, 'Conference', 'Celina', 'Abate Fetel', 'Packham's Triumph', 'Sweet Sensation', and 'Williams'. Two maturity stages, unripe and fully ripened, were investigated. Furthermore, the efficacy of trimethyl-chitosan-coated pear surfaces in preventing Penicillium expansum (P. expansum) growth was assessed. Basic maturity indices (CIE color, ethylene evolution, firmness, soluble solids), cuticle contact angle, roughness, and zeta potential were analyzed. Surface roughness was measured using an optical profilometer, hydrophobicity was measured via profilometry, and zeta potential was quantified using an electrokinetic analyzer. The 'Celina' cultivar exhibited the highest roughness, whereas 'Williams' had the lowest roughness. All the cultivars' cuticles demonstrated hydrophilic characteristics, with contact angles ranging between 65° and 90°. For pH values exceeding 3.5, all pear surfaces exhibited a negative zeta potential. P. expansum growth was the slowest on the 'Packham's Triumph' and 'Conference' cultivars. Treatment with trimethyl chitosan effectively inhibited P. expansum growth in the initial hours of incubation. In conclusion, diverse pear cultivars manifest distinct biophysical surface properties and varying susceptibility to P. expansum growth. The growth of P. expansum correlates positively with roughness, contact angle, and zeta potential. These differences can significantly impact shelf life potential and the overall postharvest quality of pears. [ABSTRACT FROM AUTHOR]

To determine the optimal germination temperature for Pyrus ussuriensis seeds and whether they experienced the phenomenon of thermodormancy and its inciting factors, several germination tests were conducted using non-dormant P. ussuriensis seeds for comparison. The results showed that the highest germination rate of P. ussuriensis seeds was reached at a constant temperature of 5 °C and variable temperature (night/day) of 5 °C/10 °C. Constant temperatures of 25 °C for three days induced thermodormancy, triggering significant drops in seeding emergence. Thermodormancy was related to the inhibitory effect of endogenous substances in the seed coat and an elevated abscisic acid concentration. The embryo, by contrast, remained non-dormant. Thermodormant and non-dormant seed embryos showed higher germination rates than dormant seed embryos when applied exogenous abscisic acid and gibberellic acid. We found that P. ussuriensis seeds showed thermodormancy; thus, during early spring sowing, high temperatures should be avoided to prevent low seed germination capacity. Additionally, applying exogenous gibberellic acid, shading and increasing soil moisture can be helpful to enhance the species seed germination. [ABSTRACT FROM AUTHOR]

SUMMARY: The composition and abundance of soluble sugars in mature pear (Pyrus) fruit are important for its acceptance by consumers. However, our understanding of the genes responsible for soluble sugar accumulation remains limited. In this study, a S1‐group member of bZIP gene family, PbrbZIP15, was characterized from pear genome through the combined analyses of metabolite and transcriptome data followed by experimental validation. PbrbZIP15, located in nucleus, was found to function in fructose, sucrose, and total soluble sugar accumulation in pear fruit and calli. After analyzing the expression profiles of sugar‐metabolism‐related genes and the distribution of cis‐acting elements in their promoters, the glucose isomerase 1 gene (PbrXylA1), whose corresponding protein catalyzed the isomerization of glucose and fructose in vitro, was identified as a downstream target gene of PbrbZIP15. PbrbZIP15 could directly bind to the G‐box element in PbrXylA1 promoter and activate its transcription, as evidenced by chromatin immunoprecipitation‐quantitative PCR, yeast one‐hybrid, electrophoretic mobility shift assay, and dual‐luciferase assay. PbrXylA1, featuring a leucine‐rich signal peptide in its N‐terminal, was localized to the endoplasmic reticulum. It was validated to play a significant role in fructose, sucrose, and total soluble sugar accumulation in pear fruit and calli, which was associated with the upregulated fructose/glucose ratio. Further studies revealed a positive correlation between the sucrose content and the expression levels of several sucrose‐biosynthesis‐related genes (PbrFRK3/8, PbrSPS1/3/4/8, and PbrSPP1) in PbrbZIP15‐/PbrXylA1‐transgenic fruit/calli. In conclusion, our results suggest that PbrbZIP15‐induced soluble sugar accumulation during pear development is at least partly attributed to the activation of PbrXylA1 transcription. Significance Statement: The composition and abundance of soluble sugars in mature pear fruit are important for its acceptance by consumers, but our understanding of the molecular mechanism underlying soluble sugar accumulation remains limited. Our findings suggest that PbrbZIP15 and its target gene PbrXylA1 participate in glucose isomerization and thus alter the composition and abundance of soluble sugars, ultimately resulting in the sweetness improvement in pear, making them potential targets for molecular breeding. [ABSTRACT FROM AUTHOR]

Bees have been known to visit the male-fertile cultivars of self-incompatible flowering plants more frequently than the male-sterile cultivars, but the origin of this preference is poorly understood. Here, we demonstrate that this preference is driven by the higher protein/lipid ratio of male-fertile pollen compared with male-sterile pollen by way of two caged-behavioral assays with six cultivars. In the first assay, flower-naïve bumblebees (Bombus ignitus Smith) showed a significantly higher flower-visitation rate to male-fertile cultivars (pollen germination rate > 55%; > 14 visits/10 min) of the Japanese pear (Pyrus pyrifolia Nakai) than male-sterile cultivars (pollen germination rate ≤ 20%; > 6 visits/10 min). In the second, bees still preferred the anthers of male-fertile cultivars (5–9 visits/10 min) more than those of male-sterile ones (less than 1 visit in 10 min) even in the absence of all other organs (i.e., petals, pistil, nectar), indicating that pollen is responsible for the preference. We then analyzed the macronutrient content of the pollen and its visual cues, and found that the bee preference was highly correlated with the protein/lipid ratio (0.3–1.6) but not color variables such as (a)chromatic contrast, intensity, and spectral purity. We conclude that the protein/lipid ratio influences the foraging behavior of the bumblebees likely by serving as (1) a chemotactile cue while antennating, (2) a gustatory cue after intake, and (3) an olfactory cue. In addition, the low bee visitation rate to poorly viable pollen could be due to its low protein/lipid ratio. [ABSTRACT FROM AUTHOR]

Simple Summary: This study explores the effectiveness of the use of cactus pear meal in the feeding of laying hens to improve production and reduce costs. The objective was to evaluate the impact of different proportions of this flour on the birds' diet. The variety "Miúda" of cactus pear was found to be the most efficient, improving energy utilization and nutrient digestibility. Although the birds' productive performance was not significantly affected by the use of up to 9% of flour in the diet, improvements were observed in egg quality, including in the texture and color of the yolk, as well as a healthier composition in terms of fatty acids and cholesterol. The study concludes that a 3% inclusion of cactus pear meal is the most economically suitable, offering benefits without compromising quality or performance. These findings are important for egg farmers who seek sustainable and economical alternatives, thus contributing to a more conscious society regarding food production and nutrition. Little information is available in the literature on the use of cactus pear meal (CPM) in poultry diets; therefore, it is important to evaluate diets that provide excellent performance and lower production costs. Our objective was to study the use of Miúda CPM in the diets of laying hens. In the first study, two diets for male and female chicks were used—1: 80% reference diet + 20% Miúda cactus pear meal (CPM) and 2: 80% reference diet + 20% Gigante cactus pear meal (CPM). The variety Miúda provided a better use of metabolizable energy, as well as a greater digestibility coefficient of dry matter, protein, and mineral matter. In the second study, a control diet was compared to three diets with different levels of Miúda CPM for laying hens in the proportions of 3%, 6%, and 9%. No significant differences were found in productive performance. However, there were significant differences in the some parameters egg quality, texture and color profile of the cooked yolk, egg composition, fatty acids and cholesterol in the yolk. It is possible to use 9% Miúda CPM in the diet of laying hens in a semi-intensive system that does not compromise performance and egg quality, and using 3% Miúda CPM provides a higher economic return. [ABSTRACT FROM AUTHOR]

Pear pomace, a byproduct of juice production, represents a valuable reservoir of bioactive compounds with potential health benefits for humans. This study aimed to evaluate the influence of drying method and temperature on pear pomace, specifically focusing on the drying kinetics, grinding characteristics, color, phenolic profile (LC-MS/MS), and antioxidant activities of the powder. Drying using the contact method at 40 °C with microwave assistance demonstrated the shortest duration, whereas freeze-drying was briefer compared to contact-drying without microwave assistance. Freeze-drying resulted in brighter and more easily comminuted pomace. Lyophilized samples also exhibited higher total phenolic compound levels compared to contact-dried ones, correlating with enhanced antioxidant activity. Twenty-one phenolic compounds were identified, with dominant acids being quinic, chlorogenic, and protocatechuic. Flavonoids, primarily isoquercitrin, and rutin, were also presented. Pear pomace dried via contact at 60 °C contained more quinic and protocatechuic acids, while freeze-dried pomace at the same temperature exhibited higher levels of chlorogenic acid, epicatechin, and catechin. The content of certain phenolic components, such as gallic acid and epicatechin, also varied depending on the applied drying temperature. [ABSTRACT FROM AUTHOR]

The Chinese white pear (Pyrus bretschneideri) fruit carries a high proportion of stone cells, adversely affecting fruit quality. Lignin is a main component of stone cells in pear fruit. In this study, we discovered that a pear MYB transcription factor, PbMYB80, binds to the promoters of key lignin biosynthesis genes and inhibits their expression. Stable overexpression of PbMYB80 in Arabidopsis showed that lignin deposition and secondary wall thickening were inhibited, and the expression of the lignin biosynthesis genes in transgenic Arabidopsis was decreased. Transient overexpression of PbMYB80 in pear fruit inhibited lignin metabolism and stone cell development, and the expression of some genes in the lignin metabolism pathway was reduced. In contrast, silencing PbMYB80 with VIGS increased the lignin and stone cell content in pear fruit, and increased expression of genes in the lignin metabolism pathway. By screening a pear fruit cDNA library in yeast, we found that PbMYB80 binds to a RING finger (PbRHY1) protein. We also showed that PbRHY1 exhibits E3 ubiquitin ligase activity and degrades ubiquitinated PbMYB80 in vivo and in vitro. This investigation contributes to a better understanding of the regulation of lignin biosynthesis in pear fruit, and provides a theoretical foundation for increasing pear fruit quality at the molecular level. [ABSTRACT FROM AUTHOR]

• Desirable inhibition of browning rate and enzyme (PPO/POD) activities were found with the progression of 15 days of storage under 4 ± 1 ℃. • Findings suggest herbal extract coating can be an effective alternative to chemical coating due to its increased antioxidant activity. • 80 and 60 % inhibition of phenolase and peroxidase were observed in coated pear slices in comparison with control pear slices. • C. sinensis extract was better among all applied herbs in inhibiting discoloration enzymes and showed a lower browning index. The main objective of the research study is to evaluate the effect of herbs (O. basilicum, O. vulgare, C. sinensis) extract-coated pear slices on its physiochemical quality attributes, discoloration rate, and browning enzyme activity in comparison with chemical (ascorbic acid) coated pear slices over 15 days at 4 ± 1 ℃. A significant difference (p < 0.05) between herbs and ascorbic acid-coated pear slices was obtained in terms of physiochemical quality attributes, whereby the highest variation was obtained in uncoated pear slices (control) and the least variation was observed in herbs-coated pear slices, more specifically C. sinensis spray, and dip (6 min) extract showed the highest inhibition of PPO/POD activity and the minimum browning index was noticeable throughout 15 days of storage. These findings showed that herbal extract coating application to fresh-cut pears might be a desirable strategy to alleviate discoloration, also considered to be an effective alternative to chemical coating. [ABSTRACT FROM AUTHOR]

Fire blight disease causes significant losses in pear orchards. Fire blight infection is accompanied by visual symptoms that can easily be recognized by a grower or adviser, but such visual inspection is time consuming. The present work focused on the use of convolutional neural networks (CNNs) to identify one type of visual symptom (cankers on the main trunk of dormant trees) as well as autumn blooming, which in Israel plays an important role in the epidemiology of Erwinia amylovora—the bacterium responsible for fire blight. Images of dormant trees were acquired with a tripod-mounted DSLR camera while, for autumn blooming detection, the images were acquired using a small unmanned aerial vehicle flying a few meters above the trees. In both cases, several Faster R-CNNs were trained and tested with several datasets acquired at various locations and over several years. Overall, the CNNs for canker detection achieved precision and recall rates that exceeded 90% while, for autumn blooming detection, the precision and recall rates exceeded 80% in all but one case. These trained CNNs were used to analyze automatically geo-references images, hence generating infection/blooming maps. Such maps could be one of the information layers used by growers for managing the orchard, for instance to determine whether winter sanitation is needed and/or if it was carried out properly, or to decide when and where costly manual removal of autumn flowers or copper application is required. [ABSTRACT FROM AUTHOR]