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Background: MicroRNA (miRNA) is a crucial post-transcriptional regulatory factor in plant growth and development. Duplicated genes often exhibit functional divergence due to competition for the identical miRNA binding sites. Kiwifruit (Actinidia spp.) is an economically significant horticultural crop renowned for its distinctive flavor, which is largely attributable to elevated citrate levels during fruit development. However, the mechanisms through which miRNA-targeted modules evolve following duplication events and regulate citrate biosynthesis, thereby influencing the unique flavor profile of kiwifruits, remain poorly understood. Results: In this study, we examined the expression patterns of miRNAs and interactions with their targets in kiwifruit fruit samples from various pulp tissues and developmental stages. Our analysis identified 46 miRNAs, comprising 44 known miRNAs and two novel/kiwifruit-specific miRNAs, which targeted a total of 1,474 genes. Correlation analysis revealed weak relationships between the expression levels of miRNAs and their target genes. Among these targets, 27 tandemly duplicated genes, and 782 whole genome duplication (WGD) genes exhibited a loss of miRNA binding sites in one of their duplicated copies. Furthermore, weighted gene co-expression network analysis demonstrated that most duplicated genes clustered into distinct gene modules. These findings suggest that the loss of miRNA targets following duplications contributes to expression divergence among gene duplicates, thereby facilitating stable gene expression within the miRNA-targeted network. For instance, the aconitate hydratase genes AchAco4 and AchAco6 were each targeted by different miRNAs, ach-miR-3774 and ach-miR-10371, respectively. Notably, these genes exhibited distinct expression patterns compared to their duplicated counterparts. Conclusions: This study enhances our understanding of how the miRNA-AchAco module regulates citrate content and provides insights into the molecular network that influences the flavor profile of kiwifruit. Clinical trial number: Not applicable. [ABSTRACT FROM AUTHOR]

The artificial sweetener saccharin has been reported to enhance resistance against pathogen attack in various plant species. In this study, foliar application of saccharin resulted in increased resistance to leaf infection by Pseudomonas syringae pv. actinidiae biovar 3 (Psa) in two Actinidia chinensis cultivars, Hayward and Zesy002. In glasshouse plants, the application of saccharin at 0.25, 0.5, 1.0 and 2.0 g/L, 1 week before inoculation with Psa, induced a dose‐dependent reduction in leaf necrosis in both cultivars. Saccharin at 2.0 g/L reduced leaf necrosis in Hayward by 77% and in Zesy002 by over 90%. However, saccharin (2.0 g/L) did not inhibit growth of Psa in liquid media, thus suggesting induced resistance (IR) as the primary mode of action against leaf infection. The development of IR in both cultivars was concomitant with the accumulation of salicylic acid (SA) and salicylate glycoside (SAG), and the upregulation of SA‐pathway genes (PR1 and PR2) in treated leaves. In orchard‐grown Hayward vines, saccharin (1.0 g/L) induced the upregulation of SA‐pathway genes and reduced Psa leaf necrosis and flower bud rot by 50% and 25%, respectively, compared with controls. However, saccharin residues were detected in fruit collected from vines that were sprayed with saccharin (1.0 g/L) before flowering. Residue level correlated with application frequency and timing and was highest (0.051 mg/kg) in vines that received three preflowering sprays. This exceeds the default maximum residue limit (MRL; 0.01 mg/kg) for some export markets and could limit the use of saccharin for disease management. [ABSTRACT FROM AUTHOR]

Vibrational communication in the Auchenorrhyncha is an avenue of growing interest, with many pesticide‐free vibrational pest control programmes against auchenorrhynchan agricultural pests continuing to be developed around the world. Passion vine hoppers (PVH), Scolypopa australis (Walker) (Hemiptera: Ricaniidae), are an economically damaging pest species in New Zealand, where they facilitate the growth of sooty mould in kiwifruit orchards. Scolypopa australis is already known to use vibrational signals, therefore a further understanding of the spectral and temporal characteristics of its calls will be an essential next step to developing vibration‐based pest management strategies. Here, we aimed to characterise the properties of spontaneous S. australis calls in solitary and intrasexual communication contexts. We used laser Doppler vibrometry to record vibrational signals produced by male and female S. australis (separately), when in groups of three or individually. We sorted calls and call sub‐units (syllables) into groups based on cluster analyses of various spatio‐temporal parameters. We define four male calls and three female calls, and newly describe a 'two‐syllable' calling structure that may be involved in male intrasexual competition. Certain syllables were more prevalent at the beginning or end of calls for males, and were more homogenously distributed throughout calls for females. The types of calls used differed between single males and groups, with more energetically intense call types observed in the group settings. Additional studies on the behavioural context of S. australis vibrational calls and their responses to playback of such calls will be necessary to assess the viability of vibration‐based pest management for this species. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Kiwifruit (Actinidia spp.), celebrated for its unique flavor and rich nutritional content, is a globally popular fruit. This fruit requires post-harvest ripening before consumption. However, the unpredictable ripening pace significantly impacts consumer acceptance and sales, thereby hindering the commercial growth of kiwifruit. To address this, understanding the key molecular mechanisms and metabolites governing postharvest ripening and senescence could offer valuable insights for developing storage strategies and breeding techniques in yellow-fleshed kiwifruits. We constructed two models that integrated these findings with existing theories. The first model suggests that, unlike the T6P-sucrose regulatory mechanism observed in plant leaves, the separation of harvested kiwifruit from the mother plant leads to an insufficient supply of T6P, which activates the SnRK1 kinase. This, in turn, inhibits the TOR kinase signaling pathway, regulating starch metabolism. The T6P-SnRK1-TOR-starch metabolism pathway plays a regulatory role during postharvest ripening, limiting excessive starch degradation that could accelerate aging and decay in yellow-fleshed kiwifruit. The second model highlights the role of abscisic acid (ABA), cytokinins (CKs), and ethylene in regulating the process, inducing the activation of ERFs and cell wall-degrading enzymes, promoting fruit postharvest softening. These findings indicate that at least two models, the T6P-SnRK1-TOR-starch metabolism model and the ABA-CKs-ethylene-cell wall degradation model, regulate postharvest fruit ripening, offering new insights into the artificial regulation of yellow-fleshed kiwifruit ripening speed. [ABSTRACT FROM AUTHOR]

The softening process of postharvest kiwifruit is a critical aspect of fruit quality that has been extensively studied. However, the impact of indole-3-acetic acid (IAA) treatment on this process remains largely unexplored. In this study, we examined the effect of IAA treatment on the softening of postharvest kiwifruit. The results depicted that kiwifruit treated with IAA exhibited decreased firmness and increased ethylene production. Treatment with IAA upregulated the expression of starch decomposition genes, including AcSEX and AcBAM , resulting in a reduction in starch content. Additionally, IAA treatment induced cell wall breakdown, attributed to the enhanced transcript levels of cell wall-related degradation genes such as AcPE , AcPG , AcPL , and AcCX compared to the control. Consequently, IAA-treated kiwifruit displayed lower levels of cellulose and protopectin but higher levels of water-soluble pectin. In summary, our findings indicate that exogenous IAA promoted postharvest starch and cell wall biodegradation in kiwifruit, which reduced fruit firmness and accelerated fruit softening. [ABSTRACT FROM AUTHOR]

Browning reactions caused by oxidative stress occurring during postharvest procedures significantly compromise the quality of ready‐to‐eat (RTE) vegetables, negatively affecting their market value. Polyphenol oxidase (PPO) and peroxidase (POD) are two major enzymes involved in this phenomenon, as they oxidize phenolic compounds to quinones, which in turn polymerize to brown pigments. Recently, there has been an increasing interest in developing antibrowning treatments using food by‐products. Herein, the efficiency of a kiwi peel extract in reducing enzymatic browning of minimally processed lettuce (Lactuca sativa) has been investigated. PPO and POD activities showed an opposite spatial distribution within the leaf, with a higher POD activity in the midvein (MV) and in the inner lamina tissues, and a prevalence of PPO activity in the mesophyll. Considering that MV lignified tissues are those mainly affected by browning, the temporal trend of POD activity over a 20‐day storage period at 4°C was investigated. Data showed that treatment with a kiwi peel extract hinders both the increasing trend of POD activity and browning development compared to control leaves. These results could be potentially useful for the industry as they confirm that natural extracts, such as kiwi peel extract, can be valuable for extending the shelf‐life of RTE products. [ABSTRACT FROM AUTHOR]

Cold stress is one of the main abiotic stresses that affect the development and growth of kiwifruit (Actinidia arguta). Herein, we analyzed the transcriptomic data of A. arguta dormant shoots in response to low-temperature treatment, identified 52 MYB genes, and constructed a phylogenetic tree based on the encoded protein sequences. Then, the effect of one MYB gene on cold tolerance was analyzed. This gene had an open reading frame of 837 bp long and encoded 279 amino acids. Sequence alignment and phylogenetic analysis revealed that this gene belongs to the R2R3-MYB family and was named AaMYB44 based on its homology to other MYB family members. Quantitative real-time PCR revealed that AaMYB44 expression was significantly induced by low temperatures but exhibited the opposite trend in cold-tolerant genotypes. Subcellular localization assays revealed the nuclear localization of the AaMYB44 protein. Furthermore, AaMYB44 was transformed into Arabidopsis thaliana (A. thaliana) via inflorescence infection, and physiological and biochemical tests revealed that the cold resistance and antioxidant capacity of the transgenic A. thaliana were lower than those of wild-type plants. Overall, AaMYB44 might play a negative regulatory role in response to cold stress, providing new insight into the mechanism of cold tolerance. [ABSTRACT FROM AUTHOR]

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The kiwifruit (Actinidia) is an important nutritional and economic fruit crop. However, the short edible window period of kiwifruit has seriously affected its market value. 1-Methylcyclopropene (1-MCP), as a novel ethylene inhibitor, is widely applied to delay fruit ripening and senescence. To our knowledge, there are limited studies on the effects of 1-MCP on fruit quality and metabolism of different kiwifruit varieties. Three kiwifruit cultivars (i.e., 'Xuxiang', 'Huayou', and 'Hayward') widely cultivated in China were chosen as our research objects. The variations of storage quality and metabolic characteristics of kiwifruits treated with various 1-MCP concentration (0 μL/L, 0.5 μL/L, and 1.0 μL/L) were systematically investigated. The results showed that 1-MCP treatment significantly improved the quality of kiwifruit during storage. Among them, for 'Xuxiang' and 'Hayward' varieties, 1.0 μL/L 1-MCP treatment could delay the decrease in fruit firmness, the increase in maturity index and cellulase activity, and inhibit the decrease in ascorbic acid (AsA) level. However, the 0.5 μL/L 1-MCP had a great influence on the chlorophyll content and maturity index of the 'Huayou' cultivar, and the preservation effect was satisfactory. In addition, gas chromatography–mass spectrometry (GC–MS) based metabolomics studies revealed that 1-MCP treatment affected carbohydrates metabolism, fatty acids metabolism, and amino acids metabolism in different kiwifruit varieties. Correlation analysis indicated that sugars metabolism has the closest relationship with postharvest physiological quality. This research indicated that the effectiveness of 1-MCP treatments was dependent on fruit variety and treatment concentration. Furthermore, these findings provide a theoretical foundation for extending the shelf life of different kiwifruit varieties. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Beneficial rhizosphere microorganisms are widely employed to shield crops from underground pathogen infections. In this study, we challenge this conventional idea by employing rhizosphere soil bacteria to safeguard kiwi plants against the above-ground canker, caused by Pseudomonas syringae pv. actinidiae (Psa). Microbiome comparisons were conducted in different resistant cultivars Actinidia chinensis var. deliciosa 'Hayward' and A. chinensis var. chinensis 'Hongyang'. Our findings reveal the most notable disparity in the rhizosphere soil microbiome, with the Flavobacterium significantly enriched in the rhizosphere soil of more resistant cultivar, 'Hayward'. We isolated Flavobacterium isolates and observed their efficacy in preventing Psa infection, which is further confirmed in field trial by using a representative strain Flavobacterium soyae F55. Furthermore, undescribed gene clusters responsible for antimicrobial metabolite biosynthesis were identified in F. soyae F55, and F. soyae F55 growth was evidently promoted by the root exudates of 'Hayward'. The results underscore the potential of beneficial rhizosphere soil bacteria in protection against above-ground disease. A study highlights the potential of beneficial rhizosphere soil bacteria not only for controlling soil-borne diseases but also for providing cross-niche protection against above-ground diseases. [ABSTRACT FROM AUTHOR]

The kiwifruit canker disease caused by Pseudomonas syringae pv. actinidiae (Psa) seriously threatens the development of kiwifruit industry. So far, only a limited number of Psa-resistant kiwifruit varieties have been identified, and the underlying molecular mechanisms are still largely unknown. In this study, we evaluated the Psa resistance of six hybrid populations and screened a resistant segregation population R1F2. Then, transcriptome analysis on the Psa extremely high-resistant (HR) and extremely high-susceptible (HS) plants of the R1F2 population was performed. KEGG enrichment analysis revealed that differentially expressed genes (DEGs) were significantly enriched in plant hormone signal transduction pathways, including auxin, abscisic acid, zeatin, jasmonic acid and salicylic acid. Furthermore, several transcription factors (TFs), especially WRKY TFs, were identified among the DEGs. The qRT-PCR showed that AcWRKY75 was highly expressed in the HS plants. Additionally, AcWRKY75 was significantly induced in the HS cultivar 'Hongyang' after Psa inoculation. Sequence amplification analysis showed that there was polymorphism in the DNA sequence of AcWRKY75 gene, but no HR or HS-specific differences were observed. Subcellular localization and transcriptional activity analysis confirmed that AcWRKY75 functions as a nucleus-located transcriptional activator. Transient overexpression of AcWRKY75 in kiwifruit leaves reduced the resistance to Psa, while silencing AcWRKY75 by virus-induced gene silencing (VIGS) slightly enhanced the resistance to Psa. Furthermore, AcWRKY75 exhibited a weak interaction with the promoter of the ABA-related DEG AcBet V1 (Acc27163). Our findings elucidated that AcWRKY75 may negatively regulate the Psa resistance of kiwifruit through the hormone signaling pathway, which laid a foundation for the analysis of the disease resistance mechanism of kiwifruit canker. [ABSTRACT FROM AUTHOR]

The most widely cultivated species globally is Actinidia deliciosa cv. 'Hayward'. However, in recent years, consumers have shown greater demand for new varieties with novel flesh colour, flavour and appearance in international markets. To meet these expectations, one breeding study was started in 2016 at the University of Guilan in Iran to develop new kiwifruit cultivars with superior characteristics. In this breeding program, 201 female and 534 male hybrid genotypes were obtained from combinations of six different parents using the controlled cross-breeding technique. The evaluations were carried out over three consecutive stages. In the first stage, 201 female hybrid genotypes and control ('Golden') were evaluated based on 25 phenological and pomological traits. In the second stage, hybrids passed the desired threshold values in 7 key attributes were selected. Sensory testing in the next stage evaluated these selected hybrid genotypes more. As a result of the first stage, 30 hybrid genotypes with fruit weight (90 ≥ g) were selected. Then, in the second stage, 21 hybrids that showed acceptable dry matter, hue angle, flesh firmness, soluble solid content, acidity, and ascorbic acid were selected. Finally, 13 hybrid genotypes received high scores in sensory testing, and just two hybrid genotypes represented a 100% of novelty with positive texture. These genotypes were selected as potential cultivar candidates. In future studies, fruit yield, disease/pest resistance, and post-harvest performance trials of the 13 selected candidates will be evaluated at different sites. Thus, the ones that give the best results will be introduced to kiwifruit growers. [ABSTRACT FROM AUTHOR]

The unequivocal understanding of the planetary-global climate change has rendered the apportionment of sources and sinks of greenhouse gases in the terrestrial domain, an urgent priority. In the present study, the micrometeorological method of "dynamic gradient fluxes" coupled with the Monin–Obukhov similarity theory, was utilised for the determination of net ecosystem exchange of carbon dioxide (CO2) from a kiwi plantation. This annual net exchange, in conjunction with the energy and fertiliser equivalent CO2 used, established the CO2 footprint of the produce. For the year 2023, the CO2 Net Ecosystem Exchange (NEE) is −16.20 tonnes per hectare per year (CO2 uptake by the plantation). The cultivation processes used throughout the year consumed +2.96 tonnes per hectare per year, and after deduction of this value from the NEE, the result is in a net CO2 sink for the kiwi plantation of −13.24 tonnes per hectare per year. It is hence obvious that, under these conditions, the kiwi plantations in Greece can be net CO2 sinks. This result is of increasing importance since the country is the fourth largest producer of kiwi globally, with production increasing in later years. [ABSTRACT FROM AUTHOR]

Alginate oligosaccharide (AOS) is a bioactive carbohydrate known for its preservation properties. However, the efficacy of preharvest AOS treatment in maintaining the postharvest quality of hardy kiwifruit (Actinidia arguta) has not been previously reported. This study explores the effects of preharvest AOS treatment (80 mg L−1) on A. arguta fruit, assessing visual quality, physiological attributes, aroma, and antioxidant capacity during refrigeration and shelf life. Results showed that AOS treatment maintained higher lightness, chroma, firmness, and antioxidant levels (total phenolics, flavonoids, ascorbic acid, and glutathione), along with antioxidant enzyme activities (peroxidase, catalase, and ascorbate peroxidase). Specifically, AOS‐treated fruit had 9% higher chroma and double the firmness after 60 days of refrigeration. AOS treatment reduced ripening and senescence, with 25% lower soluble solids content, 22% lower respiration rate, 30% lower ethylene production, and 35% lower malondialdehyde content. Electronic nose analysis indicated that AOS treatment suppressed changes in fruit aroma and off‐odor development, maintaining significantly higher quality during the shelf life period. These findings demonstrate the effectiveness of AOS as a sustainable method to extend shelf life and preserve the quality of A. arguta fruit, enhancing its market value and consumer appeal. Practical Application: The research on using alginate oligosaccharides (AOS) for preharvest treatment of hardy kiwifruit (Actinidia arguta) has practical applications in the food industry. By extending the shelf life and preserving the quality of the fruit during storage, this method can help reduce postharvest losses and improve the market value and consumer appeal of A. arguta fruit. This sustainable preservation technique offers an eco‐friendly alternative to traditional methods, enhancing the freshness and nutritional quality of the fruit available to consumers. [ABSTRACT FROM AUTHOR]

Pseudomonas syringae pv. actinidiae biovar 3 (Psa3) causes a devastating canker disease in yellow‐fleshed kiwifruit (Actinidia chinensis). The effector HopZ5, which is present in all isolates of Psa3 causing global outbreaks of pandemic kiwifruit canker disease, triggers immunity in Nicotiana benthamiana and is not recognised in susceptible A. chinensis cultivars. In a search for N. benthamiana nonhost resistance genes against HopZ5, we found that the nucleotide‐binding leucine‐rich repeat receptor NbPTR1 recognised HopZ5. RPM1‐interacting protein 4 orthologues from N. benthamiana and A. chinensis formed a complex with NbPTR1 and HopZ5 activity was able to disrupt this interaction. No functional orthologues of NbPTR1 were found in A. chinensis. NbPTR1 transformed into Psa3‐susceptible A. chinensis var. chinensis 'Hort16A' plants introduced HopZ5‐specific resistance against Psa3. Altogether, this study suggested that expressing NbPTR1 in Psa3‐susceptible kiwifruit is a viable approach to acquiring resistance to Psa3 and it provides valuable information for engineering resistance in otherwise susceptible kiwifruit genotypes. Summary Statement: The NLR protein PTR1 from Nicotiana benthamiana is involved in the recognition of P. syringae pv. actinidiae (Psa) effector HopZ5, possibly through the plant immunity hub RPM1‐interacting protein 4. Transgenic expression of NbPTR1 in kiwifruit plants conferred immunity to Psa in a HopZ5‐specific manner. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Kiwifruit, as a climacteric fruit, undergoes rapid ripening and senescence after harvest, making it highly susceptible to softening, rotting, and spoilage. Therefore, monitoring the key quality parameters of kiwifruit, particularly the accurate detection of soluble solids content (SSC), is considered crucial. The performance of two spectral acquisition methods—diffuse reflectance and diffuse transmission—in detecting SSC in kiwifruit was compared. Various preprocessing methods and feature wavelength selection techniques were employed, and regression models were constructed using partial least squares (PLS) analysis. The stability and accuracy of the models were validated through an independent validation set. The results indicated that the spectral data acquired by the diffuse reflectance method, preprocessed using Savitzky–Golay smoothing and combined with competitive adaptive reweighted sampling (CARS), yielded a coefficient of determination (R2) of 0.98 for the prediction set, with a root-mean-square error (RMSE) of 0.66. In contrast, the spectral data obtained by the diffuse transmission method, preprocessed using multiplicative scatter correction and combined with CARS, achieved an R2 of 0.95 and an RMSE of 0.93 for the prediction set. This study demonstrated that both methods were effective for detecting SSC in kiwifruit, with the diffuse reflectance method showing the greater advantage. [ABSTRACT FROM AUTHOR]

Falling damage is the most common form of damage sustained by kiwifruit during the process of picking and post-processing, and it is difficult to conduct a quantitative analysis of this phenomenon through traditional experimental methods. In order to deeply understand the sensitivity of kiwifruit to falling collision damage, the finite element numerical simulation method was used to evaluate and predict the sensitivity of kiwifruit to falling collision damage during harvesting. First, we obtained the appearance characteristics of kiwifruit through reverse engineering technology and determined the geometric and mechanical property parameters of kiwifruit through physical mechanics experiments. Then, according to the characteristics of fruit tissue structure, a multiscale finite element model, including the skin, pulp, and core, was constructed to simulate the effects of different falling heights, collision angles, and contact surface materials on fruit damage, and the accuracy of the model was verified through falling experiments. Finally, based on the simulation results, the Box–Behnken design was employed within the response surface methodology to establish a sensitivity prediction model for the drop damage sensitivity of kiwifruit across different contact materials. The results showed that the maximum relative error between the speed change obtained using finite element simulation and the speed obtained by the high-speed camera was 5.19%. The model showed high rationality in energy distribution, with the maximum value of hourglass energy not exceeding 0.08% of the internal energy. On the contact surface material with a large elastic modulus, a higher falling height and larger collision angle will significantly increase the risk of fruit bruise. When the contact surface material was a steel plate, the falling height was 1 m, and the collision angle was 90°; the maximum bruise sensitivity of kiwifruit reached 6716.07 mm3 J−1. However, when the contact surface material was neoprene, the falling height was 0.25 m, and the collision angle was 0°, the damage sensitivity was the lowest, at 1570.59 mm3 J−1. The multiscale finite element model of kiwifruit falling collision constructed in this study can accurately predict the damage of kiwifruit during falling collision and provide an effective tool for the quantitative analysis of kiwifruit falling collision damage. At the same time, this study can also provide guidance for the design and optimization of the loss reduction method of the harvesting mechanism, which has important theoretical significance and practical value. [ABSTRACT FROM AUTHOR]

Kiwifruit growth and development are severely affected by various biotic and abiotic stresses, especially cold stress and the bacterial disease caused by Pseudomonas syringae pv. actinidiae (Psa). Metallothioneins (MTs) are a group of cysteine-rich proteins that play crucial roles in stress response, metal detoxification, and homeostasis in plants. However, the protective role of these MTs in kiwifruit remains to be elucidated. In the present study, four AcMT genes were identified in the Hongyang kiwifruit genome, namely, two Type 2 isoforms (AcMT2 and AcMT2a) and two Type 3 isoforms (AcMT3a and AcMT3b) located separately on four different chromosomes. The hormones and stress response cis-elements within the promoter regions of these AcMTs were characterized. It was revealed that the four AcMT genes exhibited different expression patterns in different tissues: AcMT2 and AcMT2a were expressed at much higher levels in the fruit, male flower, female flower, root, and bark, while AcMT3a was expressed mainly in the fruit and AcMT3b was expressed highly in the bark. The expression patterns of these AcMT genes after exposure to Psa infection and different phytohormones, including gibberellic acid A3(GA3), ethylene (ET), and abscisic acid (ABA), were evaluated. It was revealed that in response to Psa infection, the main AcMTs in each tissue (those with expression levels higher compared to the other MTs in that tissue) were downregulated during the early stage in kiwifruits, followed by a recovery phase. In addition, most AcMTs were downregulated after exposure to ET and GA3, while type 2 AcMTs (AcMT2 and AcMT2a) were upregulated after treatment with ABA. The overexpression of AcMTs in Escherichia coli presented a higher tolerance to H2O2, heavy metals, low temperature, and high temperature. Collectively, these findings demonstrated the protective roles of AcMTs in terms of stress resistance conferred through plant hormone-related signal pathways. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The microenvironmental factors of kiwifruit are constantly changing over long-distance transportation, but there are no reliable methods for monitoring and predicting quality changes. An artificial neural network (ANN) kiwifruit integrated quality dynamic prediction model based on microenvironmental parameters (i.e., temperature, relative humidity, carbon dioxide, oxygen, and ethylene levels) was developed using the correlation between microenvironmental parameters and changes in quality indicators during storage. The results showed that storage at 4 °C effectively delayed weight loss, increase in cell membrane permeability and soluble solids, as well as decrease in firmness, titratable acid content, ascorbic acid content and color (C* and L* values), delayed the onset of respiratory peaks, lowered ethylene release, and preserved kiwifruit freshness compared to 10 °C and 20 °C. The optimized back-propagation (BP) neural network model had a hidden layer neuron count of 10, and the coefficient of determination (R2) between the predicted and measured values was 0.998, with an average error within ± 5%, which was highly accurate in predicting the overall quality changes of kiwifruit during storage and transportation. [ABSTRACT FROM AUTHOR]

SUMMARY Previous research on the ripening process of many fruit crop varieties typically involved analyses of the conserved genetic factors among species. However, even for seemingly identical ripening processes, the associated gene expression networks often evolved independently, as reflected by the diversity in the interactions between transcription factors (TFs) and the targeted cis‐regulatory elements (CREs). In this study, explainable deep learning (DL) frameworks were used to predict expression patterns on the basis of CREs in promoter sequences. We initially screened potential lineage‐specific CRE–TF interactions influencing the kiwifruit ripening process, which is triggered by ethylene, similar to the corresponding processes in other climacteric fruit crops. Some novel regulatory relationships affecting ethylene‐induced fruit ripening were identified. Specifically, ABI5‐like bZIP, G2‐like, and MYB81‐like TFs were revealed as trans‐factors modulating the expression of representative ethylene signaling/biosynthesis‐related genes (e.g., ACS1, ERT2, and ERF143). Transient reporter assays and DNA affinity purification sequencing (DAP‐Seq) analyses validated these CRE–TF interactions and their regulatory relationships. A comparative analysis with co‐expression networking suggested that this DL‐based screening can identify regulatory networks independently of co‐expression patterns. Our results highlight the utility of an explainable DL approach for identifying novel CRE–TF interactions. These  imply that fruit crop species may have evolved lineage‐specific fruit ripening‐related cis–trans regulatory networks. [ABSTRACT FROM AUTHOR]

In this study, a novel active film was developed by employing ε‐polylysine (ε‐PL) as a filler in pullulan/curdlan (P/CD) composite film (P/CD/ε‐PL). The results showed that the structure of P/CD films was more uniform and denser compared to pullulan films, due to the good compatibility and intermolecular interaction between them. Among P/CD films, P/CD 6:1 film showed improved hydrophobicity, mechanical and barrier properties, and thermal stability, thereby selecting it for further use. Thereafter, the addition of ε‐PL further enhanced the structural and physicochemical properties of prepared P/CD/ε‐PL composite films, especially for P/CD/2.5%ε‐PL composite film. It exhibited improved ultraviolet barrier (about 80% at 200–400 nm), antibacterial activity (>90% against Staphylococcus aureus and Escherichia coli), and anti‐fog properties (clearly visible and transparent background). Furthermore, P/CD/2.5%ε‐PL composite film exerted its preservation effect on fresh‐cut peppers and kiwis during storage, delaying the softening, consumption of soluble solids, and deterioration. Therefore, the developed P/CD/2.5%ε‐PL composite film provided promising applications of active packing film.Practical Application: Fresh‐cut fruits and vegetables are prone to deteriorate during storage, and active packaging films play a crucial role in retaining their quality. This study was conducted to prepare a composite film by blending pullulan, curdlan, and ε‐PL and explore its structural, physicochemical, and functional properties, further verifying the preservation effect on fresh‐cut peppers and kiwis. Compared to polyethylene film, the P/CD/2.5%ε‐PL composite film delayed the softening, consumption of soluble solids, and deterioration of fresh‐cut peppers and kiwis during storage. It provides a new perspective on the preservation of fresh‐cut fruits and vegetables. [ABSTRACT FROM AUTHOR]

Pollination is critical for crop development, especially those essential for subsistence. This study addresses the pollination challenges faced by Actinidia, a dioecious plant characterized by female and male flowers on separate plants. Despite the high protein content of pollen, the absence of nectar in kiwifruit flowers poses difficulties in attracting pollinators. Consequently, there is a growing interest in using artificial intelligence and robotic solutions to enable pollination even in unfavourable conditions. These robotic solutions must be able to accurately detect flowers and discern their genders for precise pollination operations. Specifically, upon identifying female Actinidia flowers, the robotic system should approach the stigma to release pollen, while male Actinidia flowers should target the anthers to collect pollen. We identified two primary research gaps: (1) the lack of gender-based flower detection methods and (2) the underutilisation of contemporary deep learning models in this domain. To address these gaps, we evaluated the performance of four pretrained models (YOLOv8, YOLOv5, RT-DETR and DETR) in detecting and determining the gender of Actinidia flowers. We outlined a comprehensive methodology and developed a dataset of manually annotated flowers categorized into two classes based on gender. Our evaluation utilised k-fold cross-validation to rigorously test model performance across diverse subsets of the dataset, addressing the limitations of conventional data splitting methods. DETR provided the most balanced overall performance, achieving precision, recall, F1 score and mAP of 89%, 97%, 93% and 94%, respectively, highlighting its robustness in managing complex detection tasks under varying conditions. These findings underscore the potential of deep learning models for effective gender-specific detection of Actinidia flowers, paving the way for advanced robotic pollination systems. [ABSTRACT FROM AUTHOR]

ABSTRACT Pseudomonas syringae pv. actinidiae biovar 3 (Psa3) has decimated kiwifruit orchards growing susceptible kiwifruit Actinidia chinensis varieties. Effector loss has occurred recently in Psa3 isolates from resistant kiwifruit germplasm, resulting in strains capable of partially overcoming resistance present in kiwiberry vines (Actinidia arguta, Actinidia polygama, and Actinidia melanandra). Diploid male A. melanandra recognises several effectors, sharing recognition of at least one avirulence effector (HopAW1a) with previously studied tetraploid kiwiberry vines. Sequencing and assembly of the A. melanandra genome enabled the characterisation of the transcriptomic response of this non‐host to wild‐type and genetic mutants of Psa3. A. melanandra appears to mount a classic effector‐triggered immunity (ETI) response to wildtype Psa3 V‐13, as expected. Surprisingly, the type III secretion (T3SS) system‐lacking Psa3 V‐13 ∆hrcC strain did not appear to trigger pattern‐triggered immunity (PTI) despite lacking the ability to deliver immunity‐suppressing effectors. Contrasting the A. melanandra responses to an effectorless Psa3 V‐13 ∆33E strain and to Psa3 V‐13 ∆hrcC suggested that PTI triggered by Psa3 V‐13 was based on the recognition of the T3SS itself. The characterisation of both ETI and PTI branches of innate immunity responses within A. melanandra further enables breeding for durable resistance in future kiwifruit cultivars. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The kiwifruit industry typically uses commercial pollen for artificial pollination. However, during the collection of male flowers and pollen production, pollen can be easily contaminated by pathogenic bacteria that cause diseases such as canker and flower rot. Consequently, it is crucial to understand the structure of the pollen microbial community. This study employed Illumina high-throughput sequencing technology to analyze the fungal and bacterial composition in pollen samples from various regions in Shaanxi Province. Concurrently, potential pathogenic strains were isolated using traditional microbial isolation and cultivation techniques, and their molecular identification was performed through 16S rDNA sequence analysis. A tieback test was conducted on healthy branches to verify the pathogenicity of the strains. The results revealed a rich diversity of fungi and bacteria in kiwifruit pollen. At the phylum level, pollen fungi were mainly distributed in Ascomycota, and bacteria were mainly distributed in Proteobacteria and Firmicutes. The dominant fungal genera were Mycosphaerella, Aspergillus, and Cladosporium; the dominant bacterial genera were Weissella, Pantoea, Enterobacter, and Pseudomonas, respectively. Additionally, both Erwinia persicina and Pseudomonas fluorescens, isolated from pollen, exhibited high pathogenicity toward healthy kiwifruit branches. These findings contribute to a deeper understanding of the microbial diversity in commercial kiwifruit pollen used for mass pollination. [ABSTRACT FROM AUTHOR]

The bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae (Psa) is the most devastating disease threatening the global kiwifruit production. This pathogen delivers multiple effector proteins into plant cells to resist plant immune responses and facilitate their survival. Here, we focused on the unique effector HopZ5 in Psa, which previously has been reported to have virulence functions. In this study, our results showed that HopZ5 could cause macroscopic cell death and trigger a serious immune response by agroinfiltration in Nicotiana benthamiana, along with upregulated expression of immunity-related genes and significant accumulation of reactive oxygen species and callose. Subsequently, we confirmed that HopZ5 interacted with the phosphoserine-binding protein GF14C in both the nonhost plant N. benthamiana (NbGF14C) and the host plant kiwifruit (AcGF14C), and silencing of NbGF14C compromised HopZ5-mediated cell death, suggesting that GF14C plays a crucial role in the detection of HopZ5. Further studies showed that overexpression of NbGF14C both markedly reduced the infection of Sclerotinia sclerotiorum and Phytophthora capsica in N. benthamiana, and overexpression of AcGF14C significantly enhanced the resistance of kiwifruit against Psa, indicating that GF14C positively regulates plant immunity. Collectively, our results revealed that the virulence effector HopZ5 could be recognized by plants and interact with GF14C to activate plant immunity. [ABSTRACT FROM AUTHOR]

Real-time detection of kiwifruits in natural environments is essential for automated kiwifruit harvesting. In this study, a lightweight convolutional neural network called the YOLOv4-GS algorithm was proposed for kiwifruit detection. The backbone network CSPDarknet-53 of YOLOv4 was replaced with GhostNet to improve accuracy and reduce network computation. To improve the detection accuracy of small targets, the upsampling of feature map fusion was performed for network layers 151 and 154, and the spatial pyramid pooling network was removed to reduce redundant computation. A total of 2766 kiwifruit images from different environments were used as the dataset for training and testing. The experiment results showed that the F1-score, average accuracy, and Intersection over Union (IoU) of YOLOv4-GS were 98.00%, 99.22%, and 88.92%, respectively. The average time taken to detect a 416x416 kiwifruit image was 11.95 ms, and the model's weight was 28.8 MB. The average detection time of GhostNet was 31.44 ms less than that of CSPDarknet-53. In addition, the model weight of GhostNet was 227.2 MB less than that of CSPDarknet-53. YOLOv4-GS improved the detection accuracy by 8.39% over Faster R-CNN and 8.36% over SSD-300. The detection speed of YOLOv4-GS was 11.3 times and 2.6 times higher than Faster R-CNN and SSD-300, respectively. In the indoor picking experiment and the orchard picking experiment, the average speed of the YOLOv4-GS processing video was 28.4 fps. The recognition accuracy was above 90%. The average time spent for recognition and positioning was 6.09 s, accounting for about 29.03% of the total picking time. The overall results showed that the YOLOv4-GS proposed in this study can be applied for kiwifruit detection in natural environments because it improves the detection speed without compromising detection accuracy. [ABSTRACT FROM AUTHOR]

Proanthocyanidins (PAs) are important metabolites that enhance freezing tolerance of plants. Actinidia arguta, especially freezing‐tolerant germplasms, accumulate abundant PAs in dormant shoots and thereby enhance freezing tolerance, but the underlying mechanism is unknown. In this study, we used two A. arguta with contrasting cold‐resistant phenotypes, KL and RB, to explore the mechanisms in response to cold tolerance. We determined that a leucoanthocyanidin reductase gene (AaLAR1) was more highly expressed in freezing‐tolerant KL than in freezing‐sensitive RB. Moreover, overexpressing AaLAR1 in kiwifruit promoted PAs biosynthesis and enhanced cold tolerance. The AaLAR1 promoters of various A. arguta germplasms differ due to the presence of a 60‐bp deletion in cold‐tolerant genotypes that forms a functional binding site for MYC‐type transcription factor. Yeast one‐hybrid and two‐hybrid, dual‐luciferase reporter, bimolecular fluorescence complementation and coimmunoprecipitation assays indicated that the AaMYC2a binds to the MYC‐core cis‐element in the AaLAR1 promoter with the assistance of AaMYB5a, thereby promoting PAs accumulation in the shoots of cold‐tolerant kiwifruit. We conclude that the variation in the AaLAR1 promoter and the AaMYC2a–AaMYB5a–AaLAR1 module shape freezing tolerance in A. arguta. The identification of a key structural variation in the AaLAR1 promoter offers a new target for resistance breeding of kiwifruit. Summary statement: A 60‐bp deletion in the AaLAR1 promoter leads to an additional MYC‐core motif that plays a major role in freezing tolerance in kiwifruit (Actinidia arguta). AaMYC2a binds to the MYC motif of AaLAR1 promoter with the assistance of AaMYB5a, promoting proanthocyanidins accumulation and enhancing freezing tolerance. [ABSTRACT FROM AUTHOR]

A new species of Cryptognathus, C. deliciosussp. nov., is described from kiwifruit (Actinidiaceae: Actinidia deliciosa) imported from New Zealand on several occasions. The new species is most similar to C. australiensis Luxton, 1973, with which it shares very short dorsal setae. These collections represent two surprising findings. First, that Cryptognathidae, which are usually regarded as edaphic mites associated with damp habitats like moss, also occupy low arboreal habitats. Second, that these mites, which show potential for short-range endemism, include several species that could be spread around the world on agricultural produce. [ABSTRACT FROM AUTHOR]

The current systematic review and meta‐analysis was conducted to evaluate the effects of kiwifruit intake on anthropometric indices and key cardiometabolic parameters. Related articles were found by searching PubMed, ISI Web of Science, and Scopus to detect relevant Randomized Clinical Trials (RCTs) and novel systematic reviews relating to kiwi consumption in adults, up to August 2023. The weighted mean difference (WMD) and 95% confidence intervals (CIs) were calculated using a random‐effects model. Heterogeneity, sensitivity analysis, and publication bias were assessed and reported using standard methods. Six RCTs were included in the meta‐analysis. Analyzing overall effect sizes demonstrated a significant reduction in low‐density lipoprotein cholesterol (LDL) levels (WMD: −9.30 mg/dL; 95% CI: −17.56 to −1.04, p =.027), whereas no significant alterations of triglycerides (TG) (WMD: −12.91 mg/dL; 95% CI: −28.17 to 2.34, p =.097), total cholesterol (TC) (WMD: −7.66 mg/dL; 95% CI: −17.85 to 2.52, p =.141), high‐density lipoprotein cholesterol (HDL) (WMD: 2.87 mg/dL; 95% CI: −0.36 to 6.11, p =.141), fasting blood glucose (FBG) (WMD: 1.06 mg/dL; 95% CI: −1.43 to 3.56, p =.404), C‐reactive protein (CRP) (WMD: 0.15 mg/dL; 95% CI: −0.40, 0.70, p =.0598), body weight (BW) (WMD: 0.85 kg; 95% CI: −1.34 to 3.04, p =.448), body mass index (BMI) (WMD: 0.04 kg/m2; 95% CI: −0.75 to 0.83, p =.920), and waist circumference (WC) (WMD: 0.18 cm; 95% CI: −1.81 to 2.19, p =.855) were found. Our findings suggest that consuming kiwifruit does not have a significant impact on anthropometric indices and cardiometabolic factors, except for LDL‐C levels. [ABSTRACT FROM AUTHOR]

Actinidia chlorotic ringspot-associated virus (AcCRaV, Emaravirus actinidiae) is prevalent in Chinese kiwifruit, leading to substantial yield reduction. The intricate nature of symptoms presents diagnostic challenges, underscoring the necessity for a rapid and accurate detection method that facilitates effective control. In this investigation, AcCRaV isolates from key kiwi-producing regions in Sichuan province were collected and analyzed, with representative strains chosen as experimental materials. Primers targeting the nucleoprotein gene of AcCRaV were designed, and their codon usage was optimized to enhance performance. Various serological methods utilizing polyclonal antibodies were developed, including ELISA, dot immunobinding assay, and AcCRaV-specific gold immunochromatographic bands (AcCRaV-GICS). Field samples exhibited high specificity and sensitivity when tested using these methods. Furthermore, the results obtained from a large number of field samples are consistent with those derived from RT-PCR analysis, further validating the applicability of our approach. A detection method capable of handling a large volume of field samples infected with AcCRaV is currently lacking; thus, our system construction provides an important reference for addressing this gap. [ABSTRACT FROM AUTHOR]

Proteolytic products are extensively used in the nutraceutical sector to improve protein digestion and muscle quality in target populations (e.g., athletes or elderly). These products are processed using techniques that often lead to low purity but competitive pricing. Despite their widespread use and well-established production methods, the industry lacks standardized analytical methods for assessing these products and detecting potential fraud. This study proposes a comprehensive and harmonized pipeline for their analysis, which includes quantifying total soluble protein and proteolytic activity, as well as the determination of product stability and protein profile using SDS-PAGE and proteomic techniques. Despite the fact that protease extracts from pineapple had the highest protein content, most of the bromelain remained inactive, unlike in kiwi and papaya. SDS-PAGE revealed partial protein degradation of pineapple extracts, whereas kiwi extracts reflected a lower purification level but a higher protein integrity. The application of proteomic approaches strengthened the identification and origin tracing of the proteases. This study contributes to the development of a robust framework for analyzing proteolytic extracts, spanning from soluble protein quantification to protein profiling and activity determination. It may also ensure reliable supplier selection, high-quality manufacturing practices, and the implementation of optimal storage and formulation strategies in the nutraceutical industry. [ABSTRACT FROM AUTHOR]

This study focused on the physicochemical properties and tenderness of vacuum‐packaged beef M. semitendinosus as affected by various dilution ratios (DRs, 1:4, 1:2, and 1:1) of green kiwifruit juice extract (GKJE) with phosphate buffer during storage at 4°C for 7 days. In addition, the formation of peptides with antioxidant activity for GKJE ability to hydrolyze proteins present in beef was evaluated at different steps of in vitro digestion. Beef with GKJE showed higher tenderness than control (CTL, beef with brine solution alone) during storage, and the increased DR increased tenderness as compared to lower DRs. The addition of GKJE increased protein digestibility during in vitro digestion. To increase the antioxidant activity in the body, GKJE having a DR of 1:2 and 1:1 should be applied to the beef muscle with effective antioxidant activity. These results suggest that DRs of phosphate buffer and kiwifruit juice of 1:1 and 1:2 have the potential to be used as a meat‐tenderizing agent and could increase the digestibility of meat as well as the antioxidant capability of bioactive peptides. Practical Application: The dilution ratio of kiwi juice with phosphate buffer at 1:1 has the potential to be used as a meat‐tenderizing agent during refrigerated storage and also increase the digestibility of beef. [ABSTRACT FROM AUTHOR]

This study aimed to compare the untreated, cold plasma (CP)‐optimized (30 kV/5 mm/6.7 min), CP‐extreme (30 kV/2 mm/10 min), and thermally treated (TT) (90 ℃/5 min) kiwifruit juices based on the physicochemical (pH, total soluble solids (TSS), titratable acidity (TA), total color change (ΔE)), physical (particle size and rheology), microstructure (optical microscope), bioactive compounds (polyphenol, ascorbic acid, and sugar compounds), and sensory characteristics of kiwifruit juice. The pH, TSS, and TA were not significantly affected in CP and TT juice, whereas the ΔE (6.52) of TT juice lies in the range of "greatly visible." The microstructure characteristics of juice significantly changed after CP and thermal treatment. The cell and tissue disruption in CP‐extreme and thermally treated juice was more than CP‐optimized. The particle size of juice decreased irrespective of treatment, but the span value of CP‐optimized juice was the lowest. Further, the CP treatment showed a lower consistency index, apparent viscosity, and pseudoplasticity of juice than the thermal treatment. The CP‐treated juice retained bioactive and nutritional attributes more than thermally treated juice. The CP‐optimized, CP‐extreme, and thermal treatment reduced the sucrose content by 54, 55, and 23%, while the fructose and glucose content were increased by 17, 12, & 93%, and 17, 11 & 99%, respectively. Among the CP‐treated juice, CP‐optimized (71.36 mg/100g) contained a higher amount of ascorbic acid than the CP‐extreme (64.36 mg/100g). Based on the similarity values in the fuzzy logic analysis, the sensory attributes of CP‐optimized treated juice were superior to CP‐extreme and thermal treated. Practical Application: In this era, non‐thermal processing techniques are trending for retaining the nutrition and stability of juice. The old plasma (CP)‐treated kiwifruit juice had better nutritional, bioactive compounds, and sensory attributes than the thermally treated juice. Further, the CP‐treated juice had higher flowability and lower viscosity, making it ideal for juice processing. The conclusions drawn suggest that CP processing is a better alternative for processing kiwifruit juice than thermal processing. [ABSTRACT FROM AUTHOR]

Although the ubiquitin ligase U-box protein family is a vital component of plant development and stress response, the exact role of kiwifruit U-box genes family is not known. The study identified 73 putative U-box genes from the kiwifruit genome. Chromosomal localisation, phylogenetic analysis, physicochemical properties, gene structure, motifs, and promoters of these genes were analysed. Distribution of Actinidia chinensis PUB (AcPUB) genes exhibited varying densities across 27 chromosomes. The study found that U-box clusters were classified into groups I–VII in phylogenetic analyses of a variety of plants, including kiwifruit, Arabidopsis thaliana, and rice, with most of the genes in kiwifruit being related to rice. The conserved motif analyses revealed that all the AcPUB genes have typical U-box structural domains. Analysis of the cis-acting elements suggested that AcPUBs expression may be responsive to several hormones and stresses. RNA-Seq analysis showed that six kiwifruit U-box genes were differentially expressed after induction by Wickerhamomyces anomalus, suggesting a potential involvement of these U-box genes in the kiwifruit's response to W. anomalus, which might include mechanisms related to resistance. Overall, our findings provide valuable insights into the function and structure of U-box genes that will help develop new genomic technologies and study plant resistance. [ABSTRACT FROM AUTHOR]

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The consumption of kiwifruit (Actinidia deliciosa var. Hayward) is recognized for its health benefits due to its high vitamin C content and bioactive secondary metabolites, such as phenolic compounds with antioxidant properties. These compounds may help prevent chronic noncommunicable diseases, currently the leading cause of death. Additionally, plants and fruits contain proteins like lectins, which contribute to plant defense and may also have health-promoting effects, including antitumor and hypoglycemic activities. Objectives: The objective of this work was to evaluate and identify the phenolic compounds in this variety of kiwifruit, as well as to investigate the lectin activity and the potential dietary benefits of this combination. Methods: This study quantified and identified total phenolic compounds and flavonoids in a kiwifruit extract using HPLC-DAD-MS/MS, and assessed their antioxidant activity through the DPPH method. Results: Novel lectin activity was also investigated, with polypeptide characterization and glycoprotein profiling performed. The affinity of lectins for glycans was evaluated using a hemagglutination inhibition assay. Results indicated that kiwifruit lectins bind to glycoreceptors on tumor cell membranes, with a specific affinity for sialic acid, an important glycan in tumor-associated glycomic aberrations. Conclusions: These findings suggest that the bioactive components of kiwifruit may offer multiple health benefits through a synergistic effect. [ABSTRACT FROM AUTHOR]

Kiwifruit (Actinidia chinensis var. deliciosa) has become an important horticultural crop worldwide. Its dioecious nature challenges its commercial production, involving strategies for enhancing cross-pollination to reach a better fruit quality. The explanatory variables that can be linked to improving fruit quality analyzed in this work were pollination (through a hand-pollen application or by Apis mellifera, but also considering the ratio of female:male plants in each plot) and plant competition for resources during fruit development (controlled by thinning, but also considering plant density per plot). The response variables assessed to estimate fruit quality were fruit weight, number of seeds, and shape coefficient. We obtained different models showing how these explanatory variables influence the different indicators for fruit quality (sampling 25 fruits per plot) in seven plots. Results suggest that the female:male ratio and number of plants per hectare are the most influential explanatory variables related to fruit quality in the studied agroecosystem. The kiwifruits from plots with higher amounts of pollen manually added and higher ratios of female:male plants were significantly lighter. We recommend not settling more than 500 plants per hectare at the plot level. The natural pollination for kiwifruit production can be improved if the ratio of female:male plants per plot is ≤ 10/1 when the flowering period of both plant sexes is synchronized. Finally, we recommend that growers follow these numbers in considering the importance of planting male and female plants in close proximity but managing plant density to avoid competition for resources. [ABSTRACT FROM AUTHOR]

In order to understand the mineral content of kiwifruit produced in Meixian county, Shaanxi province and evaluate IS related nutritional value. The contents of 9 minerals in four varieties of kiwifruit, namely Xuxiang, Cuixiang, Hongxin and Huangxin, produced mainly in Shaanxi Meixaan, were determined by inductively coupled plasma atomic emission spectrometry. The nutritional evaluation of mineral elements was carried out by the index of nutritional quality (INQ) method. Simultaneously, SPSS software was used to analyze the correlation between 9 mineral and energy. The four varieties of kiwifruit in Shaanxi Meixaan were mainly composed of P,K,Ca, and Mg, accounting for approximately 99.8 V of the total minerals. The INQ greater than 1 in all four varieties included Ca,K,Mg, and Cu, and the INQ of K was the highest, ranging from 3.89 to 5.19. The total mineral content of Cuixiang was the highest, 328 mg/100g, but the highest nutritional quality index of Xuxaing was 16.78 (INQ total). The correlation analysis showed that there was varying degrees of correlation between various elements, and the highest correction coefficient between K and energy was 0.982. Kiwifruit was a high-quality food with high K and low Na. The nutritional value of mineral elements in different varieties of kiwifruit was significantly different. The highest mineral nutrient density was Cuixiang, followed by Hongxin, Huangxin, and Xuxiang. According to the nutritional value index of 9 mineral elements, Xuxiang was the highest, Cuixiang followed, and the mineral nutrition level of Hongxin and Huangxin kiwifruit were slightly lower. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Integrated pest management (IPM) plays a crucial role in protecting agricultural environments and enhancing the quality of agricultural products. However, a major challenge in China is the conflicting understanding of IPM among farmers, leading to low adoption rates. This undermines farmers' ability to control pests and diseases while increasing risks to agricultural quality and safety. This study aimed to investigate the impact of cognitive conflicts on farmers' adoption of IPM in kiwifruit farms in Shaanxi and Sichuan provinces. Additionally, the study explored the moderating role of internet use in the relationship between cognitive conflicts and farmer adoption of IPM. Data were collected from 686 kiwifruit farms through field surveys in 2018. The binary Probit model and moderating effect models were used to assess the influence of internet use and cognitive conflict on farmer adoption of IPM. RESULTS: The study found that cognitive conflicts significantly hindered farmers' adoption of IPM. Higher levels of cognitive conflict were associated with lower likelihoods of adopting IPM. Internet use and frequency had positive effects on farmer adoption of IPM, promoting its implementation. Moreover, internet use and frequency helped alleviate the inhibitory effect of cognitive conflicts on farmer adoption IPM. CONCLUSION: This research enhances our understanding of cognitive conflicts among farmers when promoting IPM and provides viable strategies to improve the effectiveness of public sector promotion and stimulate farmers' willingness to adopt IPM. It emphasizes the importance of addressing cognitive conflicts and utilizing internet resources to enhance IPM adoption among kiwifruit growers in China. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

To address the challenges associated with kiwi fruit detection methods, such as low average accuracy, inaccurate recognition of fruits, and long recognition time, this study proposes a novel kiwi fruit recognition method based on an improved lightweight network S-YOLOv4-tiny detection algorithm. Firstly, the YOLOv4-tiny algorithm utilizes the CSPdarknet53-tiny network as a backbone feature extraction network, replacing the CSPdarknet53 network in the YOLOv4 algorithm to enhance the speed of kiwi fruit recognition. Additionally, a squeeze-and-excitation network has been incorporated into the S-YOLOv4-tiny detection algorithm to improve accurate image extraction of kiwi fruit characteristics. Finally, enhancing dataset pictures using mosaic methods has improved precision in the characteristic recognition of kiwi fruits. The experimental results demonstrate that the recognition and positioning of kiwi fruits have yielded improved outcomes. The mean average precision (mAP) stands at 89.75%, with a detection precision of 93.96% and a single-picture detection time of 8.50 ms. Compared to the YOLOv4-tiny detection algorithm network, the network in this study exhibits a 7.07% increase in mean average precision and a 1.16% acceleration in detection time. Furthermore, an enhancement method based on the Squeeze-and-Excitation Network (SENet) is proposed, as opposed to the convolutional block attention module (CBAM) and efficient channel attention (ECA). This approach effectively addresses issues related to slow training speed and low recognition accuracy of kiwi fruit, offering valuable technical insights for efficient mechanical picking methods. [ABSTRACT FROM AUTHOR]

Abstract Background MicroRNA (miRNA) is a crucial post-transcriptional regulatory factor in plant growth and development. Duplicated genes often exhibit functional divergence due to competition for the identical miRNA binding sites. Kiwifruit (Actinidia spp.) is an economically significant horticultural crop renowned for its distinctive flavor, which is largely attributable to elevated citrate levels during fruit development. However, the mechanisms through which miRNA-targeted modules evolve following duplication events and regulate citrate biosynthesis, thereby influencing the unique flavor profile of kiwifruits, remain poorly understood. Results In this study, we examined the expression patterns of miRNAs and interactions with their targets in kiwifruit fruit samples from various pulp tissues and developmental stages. Our analysis identified 46 miRNAs, comprising 44 known miRNAs and two novel/kiwifruit-specific miRNAs, which targeted a total of 1,474 genes. Correlation analysis revealed weak relationships between the expression levels of miRNAs and their target genes. Among these targets, 27 tandemly duplicated genes, and 782 whole genome duplication (WGD) genes exhibited a loss of miRNA binding sites in one of their duplicated copies. Furthermore, weighted gene co-expression network analysis demonstrated that most duplicated genes clustered into distinct gene modules. These findings suggest that the loss of miRNA targets following duplications contributes to expression divergence among gene duplicates, thereby facilitating stable gene expression within the miRNA-targeted network. For instance, the aconitate hydratase genes AchAco4 and AchAco6 were each targeted by different miRNAs, ach-miR-3774 and ach-miR-10371, respectively. Notably, these genes exhibited distinct expression patterns compared to their duplicated counterparts. Conclusions This study enhances our understanding of how the miRNA-AchAco module regulates citrate content and provides insights into the molecular network that influences the flavor profile of kiwifruit. Clinical trial number Not applicable.

Objective: In order to understand the quality characteristics of kiwifruit main plant varieties in Shaanxi Province, and then provide consumers with corresponding theoretical guidance and assist the sustainable development of the kiwifruit industry in Shaanxi Province. Methods: This study analyzed the comprehensive quality and aroma characteristics of the main cultivars of kiwifruit in the Shaanxi production area, namely Cuixiang, Xuxiang, Ruiyu, Puyu, and Hayward, as the objects of the study. Results: The results showed that the juice yield of Hayward was significantly higher than that of other varieties (P

Abstract Kiwifruit (Actinidia spp.), celebrated for its unique flavor and rich nutritional content, is a globally popular fruit. This fruit requires post-harvest ripening before consumption. However, the unpredictable ripening pace significantly impacts consumer acceptance and sales, thereby hindering the commercial growth of kiwifruit. To address this, understanding the key molecular mechanisms and metabolites governing postharvest ripening and senescence could offer valuable insights for developing storage strategies and breeding techniques in yellow-fleshed kiwifruits. We constructed two models that integrated these findings with existing theories. The first model suggests that, unlike the T6P-sucrose regulatory mechanism observed in plant leaves, the separation of harvested kiwifruit from the mother plant leads to an insufficient supply of T6P, which activates the SnRK1 kinase. This, in turn, inhibits the TOR kinase signaling pathway, regulating starch metabolism. The T6P-SnRK1-TOR-starch metabolism pathway plays a regulatory role during postharvest ripening, limiting excessive starch degradation that could accelerate aging and decay in yellow-fleshed kiwifruit. The second model highlights the role of abscisic acid (ABA), cytokinins (CKs), and ethylene in regulating the process, inducing the activation of ERFs and cell wall-degrading enzymes, promoting fruit postharvest softening. These findings indicate that at least two models, the T6P-SnRK1-TOR-starch metabolism model and the ABA-CKs-ethylene-cell wall degradation model, regulate postharvest fruit ripening, offering new insights into the artificial regulation of yellow-fleshed kiwifruit ripening speed.

In order to study the effect of intermittent ozone treatment on the storage quality and preservation of kiwifruit, ‘Hayward’ kiwifruit were fumigated with different concentrations (0, 21.4, 42.8 and 64.2 mg/m3) of ozone once every seven days during storage at (0.0 ± 0.5) ℃. Quality indexes and the antioxidant enzyme activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX) were measured regularly during storage. The results showed that compared with the control group, ozone treatment at all concentrations effectively reduced fruit mass loss rate, soft fruit rate and decay rate, inhibited the increase of total soluble solid (TSS) and malondialdehyde (MDA) contents, delayed the decrease of titratable acid (TA) content and fruit hardness, and maintained higher vitamin C (VC), total phenol and flavonoid contents. The preservative effect of ozone at 42.8 mg/m3 was better than those at 21.4 and 64.2 mg/m3 concentrations. After 140-day storage, the hardness and VC content in the 42.8 mg/m3 treatment group were 76.92% and 43.10% higher than those in the control group, respectively. The peak values of catalase (CAT) and peroxidase (POD) activity were 36.53% and 89.31% higher than those of the control group, respectively. Ozone treatment also effectively controlled the soft fruit rate and decay rate of kiwifruit during the shelf-life period. On the 9th day, the decay rate of the 42.8 mg/m3 treatment group was 16.67%, which was 63.77% lower than that of the control group. It is concluded that intermittent ozone treatment at a concentration of 42.8 mg/m3 can effectively slow down the senescence process and improve the storage quality and nutritional value of kiwifruit.