Transcriptome Analysis of the Salt-Treated Actinidia deliciosa (A. Chev.) C. F. Liang and A. R. Ferguson Plantlets.

The area of saline land in the world is quite large, and there is broad room for its development and usage. 'Xuxiang' is an Actinidia deliciosa variety that is tolerant to salt and can be planted in an area of light-saline land, and has good comprehensive characteristics and high economic value. However, the molecular mechanism of salt tolerance is unknown at present. To understand the molecular mechanism of salt tolerance, the leaves of A. deliciosa 'Xuxiang' were used as explants to establish a sterile tissue culture system, and plantlets were obtained using this system. One percent concentration (w/v) of sodium chloride (NaCl) was employed to treat the young plantlets cultured in Murashige and Skoog (MS) medium, then RNA-seq was used for transcriptome analysis. The results showed that the genes related to salt stress in the phenylpropanoid biosynthesis pathway and the anabolism of trehalose and maltose pathways were up-regulated; however, those genes in the plant hormone signal transduction and metabolic pathways of starch, sucrose, glucose, and fructose were down-regulated after salt treatment. The expression levels of ten genes that were up-regulated and down-regulated in these pathways were confirmed by real-time quantitative polymerase chain reaction (RT-qPCR) analysis. The salt tolerance of A. deliciosa might be related to the expression level changes in the genes in the pathways of plant hormone signal transduction, phenylpropanoid biosynthesis, and starch, sucrose, glucose, and fructose metabolism. The increased expression levels of the genes encoding alpha-trehalose-phosphate synthase, trehalose-phosphatase, alpha-amylase, beta-amylase, feruloyl-CoA 6-hydroxylase, ferulate 5-hydroxylase, and coniferyl-alcohol glucosyl transferase might be vital to the salt stress response of the young A. deliciosa plants.

Actinidia deliciosa Extract as a Promising Supplemental Agent for Hepatic and Renal Complication-Associated Type 2 Diabetes (In Vivo and In Silico-Based Studies).

Type 2 diabetes (T2D) is a chronic metabolic condition associated with obesity, oxidative stress-mediated inflammation, apoptosis, and impaired insulin signaling. The utilization of phytochemical therapy generated from plants has emerged as a promising approach for the treatment of diabetes and its complications. Kiwifruit is recognized for its substantial content of antioxidative phenolics. Therefore, this work aimed to examine the effect of Actinidia deliciosa (kiwi fruit) on hepatorenal damage in a high-fat diet (HFD) and streptozotocin (STZ)-induced T2D in rats using in vivo and in silico analyses. An increase in hepatic and renal lipid peroxidation was observed in diabetic rats accompanied by a decrease in antioxidant status. Furthermore, it is important to highlight that there were observable inflammatory and apoptotic responses in the hepatic and renal organs of rats with diabetes, along with a dysregulation of the phosphorylation levels of mammalian target of rapamycin (mTOR), protein kinase B (Akt), and phosphoinositide 3-kinase (PI3K) signaling proteins. However, the administration of kiwi extract to diabetic rats alleviated hepatorenal dysfunction, inflammatory processes, oxidative injury, and apoptotic events with activation of the insulin signaling pathway. Furthermore, molecular docking and dynamic simulation studies revealed quercetin, chlorogenic acid, and melezitose as components of kiwi extract that docked well with potential as effective natural products for activating the silent information regulator 1(SIRT-1) pathway. Furthermore, phenolic acids in kiwi extract, especially syringic acid, P-coumaric acid, caffeic acid, and ferulic acid, have the ability to inhibit the phosphatase and tensin homolog (PTEN) active site. In conclusion, it can be argued that kiwi extract may present a potentially beneficial adjunctive therapy approach for the treatment of diabetic hepatorenal complications.

Characterization and Pathogenicity of Pythium-Like Species Associated with Root and Collar Rot of Kiwifruit in Turkey.

During the period of June to October in 2018, a widespread decline was observed on kiwifruit vines in the vineyards located in the Altinordu, Fatsa, and Persembe districts of Ordu province in Turkey. The symptoms were associated with reddish-brown rots expanding from the root to the collar with sparse off-color foliage. Based on the percentage of the total infected samples across 18 vineyards, the most common oomycete species were Globisporangium intermedium (37.1%), Phytopythium vexans (34.3%), Globisporangium sylvaticum (14.3%), Globisporangium heterothallicum (11.4%), and Pythium dissotocum (2.9%). The morphological identification of isolates was confirmed based on partial DNA sequences containing the nuclear rDNA internal transcribed spacer region gene and the mitochondrial cytochrome c oxidase subunit II gene. The optimum growth temperature and the optimum pH values of the five species ranged from 22.98 to 28.25°C and 5.67 to 8.51, respectively. Pathogenicity tests on the seedlings of kiwifruit cv. Hayward revealed significant differences in virulence among isolates. Phytopythium vexans and Globisporangium sylvaticum isolates caused severe root and collar rot resulting in seedling death, while Globisporangium heterothallicum and Globisporangium intermedium isolates had relatively lower virulence. All Globisporangium spp. and Phytopythium vexans isolates significantly decreased plant growth parameters (plant height, shoot and root dry weights, and root length); however, Pythium dissotocum caused very mild symptoms and did not affect these parameters of growth. To our knowledge, this is the first study reporting Globisporangium sylvaticum, Globisporangium heterothallicum, and Globisporangium intermedium causing root and collar rot on kiwifruit not only in Turkey but also in the world.

Carrot DcALFIN4 and DcALFIN7 Transcription Factors Boost Carotenoid Levels and Participate Differentially in Salt Stress Tolerance When Expressed in Arabidopsis thaliana and Actinidia deliciosa.

ALFIN-like transcription factors (ALs) are involved in several physiological processes such as seed germination, root development and abiotic stress responses in plants. In carrot (Daucus carota), the expression of DcPSY2, a gene encoding phytoene synthase required for carotenoid biosynthesis, is induced after salt and abscisic acid (ABA) treatment. Interestingly, the DcPSY2 promoter contains multiple ALFIN response elements. By in silico analysis, we identified two putative genes with the molecular characteristics of ALs, DcAL4 and DcAL7, in the carrot transcriptome. These genes encode nuclear proteins that transactivate reporter genes and bind to the carrot DcPSY2 promoter in yeast. The expression of both genes is induced in carrot under salt stress, especially DcAL4 which also responds to ABA treatment. Transgenic homozygous T3 Arabidopsis thaliana lines that stably express DcAL4 and DcAL7 show a higher survival rate with respect to control plants after chronic salt stress. Of note is that DcAL4 lines present a better performance in salt treatments, correlating with the expression level of DcAL4, AtPSY and AtDXR and an increase in carotenoid and chlorophyll contents. Likewise, DcAL4 transgenic kiwi (Actinidia deliciosa) lines show increased carotenoid and chlorophyll content and higher survival rate compared to control plants after chronic salt treatment. Therefore, DcAL4 and DcAL7 encode functional transcription factors, while ectopic expression of DcAL4 provides increased tolerance to salinity in Arabidopsis and Kiwi plants.

Fragrance addition improves visitation by honeybees and fruit quality in kiwifruit (Actinidia deliciosa).

BACKGROUND: Kiwifruit is an important horticultural crop all over the world and its development is important in Argentina. This dioecious crop has a short blooming period with nectarless flowers, and its fruit production depends on cross-pollination. Here, we tested whether kiwifruit quality increases by using honeybees exposed to female flowers treated with an artificial fragrance. The three experimental treatments were: A, sprinkled female flowers with 1:1 sugar syrup + Lavandula hybrida extract solution (a new attractant substance especially developed for this study named Lavandin Grosso); B, sprinkled female flowers with 1:1 water + sugar syrup (female flowers with additional sugar syrup reward); C (control; female flowers exposed to honeybees). RESULTS: The results showed a higher number of visits of honeybees to the female flowers sprinkled with the attractant substance, Lavandin Grosso, as well as higher fruit quality (weight, number of seeds, regularity in fruit size). CONCLUSION: Our study demonstrates the potential of fragrance-treated flowers to improve yield production in kiwifruit. © 2021 Society of Chemical Industry.

Untargeted and Targeted Metabolomics and Tryptophan Decarboxylase In Vivo Characterization Provide Novel Insight on the Development of Kiwifruits (Actinidia deliciosa).

Kiwifruit (Actinidia deliciosa cv. Hayward) is a commercially important crop with highly nutritional green fleshy fruits. The post-harvest maturation of the fruits is well characterized, but little is known about the metabolic changes that occur during fruit development. Here we used untargeted metabolomics to characterize the non-volatile metabolite profile of kiwifruits collected at different time points after anthesis, revealing profound metabolic changes before the onset of ripening including the depletion of many classes of phenolic compounds. In contrast, the phytohormone abscisic acid accumulated during development and ripening, along with two indolamines (serotonin and its precursor tryptamine), and these were monitored in greater detail by targeted metabolomics. The role of indolamines in kiwifruit development is completely unknown, so we also characterized the identity of genes encoding tryptophan decarboxylase in A. deliciosa and its close relative A. chinensis to provide insight into the corresponding biological processes. Our results indicate that abscisic acid and indolamines fulfill unrecognized functions in the development and ripening of kiwifruits.

AdRAP2.3, a Novel Ethylene Response Factor VII from Actinidia deliciosa, Enhances Waterlogging Resistance in Transgenic Tobacco through Improving Expression Levels of PDC and ADH Genes.

APETALA2/ethylene-responsive factor superfamily (AP2/ERF) is a transcription factor involved in abiotic stresses, for instance, cold, drought, and low oxygen. In this study, a novel ethylene-responsive transcription factor named AdRAP2.3 was isolated from Actinidia deliciosa 'Jinkui'. AdRAP2.3 transcription levels in other reproductive organs except for the pistil were higher than those in the vegetative organs (root, stem, and leaf) in kiwi fruit. Plant hormones (Salicylic acid (SA), Methyl-jasmonate acid (MeJA), 1-Aminocyclopropanecarboxylic Acid (ACC), Abscisic acid (ABA)), abiotic stresses (waterlogging, heat, 4 °C and NaCl) and biotic stress (Pseudomonas Syringae pv. Actinidiae, Psa) could induce the expression of AdRAP2.3 gene in kiwi fruit. Overexpression of the AdRAP2.3 gene conferred waterlogging stress tolerance in transgenic tobacco plants. When completely submerged, the survival rate, fresh weight, and dry weight of transgenic tobacco lines were significantly higher than those of wile type (WT). Upon the roots being submerged, transgenic tobacco lines grew aerial roots earlier. Overexpression of AdRAP2.3 in transgenic tobacco improved the pyruvate decarboxylase (PDC) and alcohol dehydrogenase (ADH) enzyme activities, and improved the expression levels of waterlogging mark genes NtPDC, NtADH, NtHB1, NtHB2, NtPCO1, and NtPCO2 in roots under waterlogging treatment. Overall, these results demonstrated that AdRAP2.3 might play an important role in resistance to waterlogging through regulation of PDC and ADH genes in kiwi fruit.

Using artificial neural network in determining postharvest LIFE of kiwifruit.

BACKGROUND: Artificial intelligence systems have been employed for the development of predictive models that estimate many agricultural processes. RESULTS: In present study, the predictive capabilities of artificial neural networks (ANNs) were evaluated with respect to assessing fruit firmness as a postharvest life index, with determinations made at four stages of storage: 1, 60, 120 and 180 days after harvesting. Single concentrations of nitrogen (N), potassium (K), calcium (Ca) and magnesium (Mg) on fruit (D1 ), all of these nutrient concentrations (D2 ), the ratios of the nutrient concentrations alone (D3 ), and a combination of nutrient concentrations and their ratios (D4 ), were considered. CONCLUSION: The results obtained showed that fruit firmness at 1 and 60 days after harvesting was not influenced by nutrients. However, the ANN model estimated fruit firmness of 120 and 180 days, respectively, for D1 and D3 more accurately than for the D2 and D4 datasets. Application of D3 (nitrogen/calcium ratio) as the input dataset improved predictions of fruit firmness, with a correlation coefficient of 0.85 between the measured and estimated data. © 2019 Society of Chemical Industry.

Ozone-induced inhibition of kiwifruit ripening is amplified by 1-methylcyclopropene and reversed by exogenous ethylene.

BACKGROUND: Understanding the mechanisms involved in climacteric fruit ripening is key to improve fruit harvest quality and postharvest performance. Kiwifruit (Actinidia deliciosa cv. 'Hayward') ripening involves a series of metabolic changes regulated by ethylene. Although 1-methylcyclopropene (1-MCP, inhibitor of ethylene action) or ozone (O3) exposure suppresses ethylene-related kiwifruit ripening, how these molecules interact during ripening is unknown. RESULTS: Harvested 'Hayward' kiwifruits were treated with 1-MCP and exposed to ethylene-free cold storage (0 °C, RH 95%) with ambient atmosphere (control) or atmosphere enriched with O3 (0.3 µL L- 1) for up to 6 months. Their subsequent ripening performance at 20 °C (90% RH) was characterized. Treatment with either 1-MCP or O3 inhibited endogenous ethylene biosynthesis and delayed fruit ripening at 20 °C. 1-MCP and O3 in combination severely inhibited kiwifruit ripening, significantly extending fruit storage potential. To characterize ethylene sensitivity of kiwifruit following 1-MCP and O3 treatments, fruit were exposed to exogenous ethylene (100 µL L- 1, 24 h) upon transfer to 20 °C following 4 and 6 months of cold storage. Exogenous ethylene treatment restored ethylene biosynthesis in fruit previously exposed in an O3-enriched atmosphere. Comparative proteomics analysis showed separate kiwifruit ripening responses, unraveled common 1-MCP- and O3-dependent metabolic pathways and identified specific proteins associated with these different ripening behaviors. Protein components that were differentially expressed following exogenous ethylene exposure after 1-MCP or O3 treatment were identified and their protein-protein interaction networks were determined. The expression of several kiwifruit ripening related genes, such as 1-aminocyclopropane-1-carboxylic acid oxidase (ACO1), ethylene receptor (ETR1), lipoxygenase (LOX1), geranylgeranyl diphosphate synthase (GGP1), and expansin (EXP2), was strongly affected by O3, 1-MCP, their combination, and exogenously applied ethylene. CONCLUSIONS: Our findings suggest that the combination of 1-MCP and O3 functions as a robust repressive modulator of kiwifruit ripening and provide new insight into the metabolic events underlying ethylene-induced and ethylene-independent ripening outcomes.

Effect of secondary metabolite of Actinidia deliciosa on the biofilm and extra-cellular matrix components of Acinetobacter baumannii.

Acinetobacter baumannii, opportunistic nosocomial pathogen, increases gradually in the clinical setup. The high level of resistance mechanisms acquired by these bacteria makes their eradication difficult and biofilm formation is one of them. Biofilm comprises of closely packed bacterial population crowded together by extra-cellular matrix (ECM). ECM contains bacterial secreted polymers such as exopolysaccharides (EPS), proteins and extracellular-DNA (e-DNA) and rarely amyloidogenic proteins. Biofilm offers protection of underlying bacterial population against chemotherapeutic agents and host immune system. Therefore, present efforts are focused to find a novel therapeutic that targets biofilm-associated infections. Plants are used as a natural therapeutic for numerous ailments. In order to find an alternative of the available antibacterial drugs, we have focused on the natural herbal active compounds. In this study, we have extracted active compounds from various medicinal plants and screened its anti-biofilm activity against carbapenem resistant strain of A. baumannii. Results showed that polar extract of kiwi (Actinidia deliciosa) and clove (Syzygium aromaticum) exhibit effective anti-biofilm activity. These two plants were also used for their phytochemical screening and TLC profiling to find out the constituting secondary metabolites. Actinidia deliciosa extract contains an alkaloid (sanquinarine) as well as a flavonoid (hydroxyflavone). Anti-biofilm effect of this extract on the ECM of A. baumannii showed that it reduces EPS, protein and eDNA contents in the ECM. Proteins of ECM have also shown to form amyloid like structure, which was evident from its interaction with the Congo Red. CFU counting after Actinidia deliciosa extract treatment also supported the results. Therefore, it can be concluded that polar extract of A. deliciosa can be used to find suitable alternative therapeutic to control biofilm formation by carbapenem resistant strain of Acinetobacter baumannii.

Influence of Cultivation Parameters on the Mineral Composition of Kiwi Fruit from Corsica.

The effect of four cultivation parameters (postmaturity harvest date, storage period at 0 °C, and input of nitrogen and potassium fertilizers) on the mineral composition of kiwi fruit (Actinidia deliciosa var. Hayward) from Corsica were evaluated. The kiwi fruit were harvested on three dates at two-week intervals and some fruit were stored for three and four months. The kiwi fruit orchard was fertilized with controlled levels of nitrogen (five levels) and potassium (three levels) during one growing season. The concentrations of 67 elements in kiwi fruit were measured using various analytical methods, such as flow injection spectrophotometry, flame atomic absorption spectrometry, flame atomic emission spectrometry, electrothermal atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry, inductively coupled plasma mass spectrometry, and filtration. The main elements in kiwi fruit are K, N, Cl, P, and Si and, to a lesser amount, Ca, Mg, Na, and Fe. This study demonstrates a high degree of difference in the amount of 23 mineral elements depending on the harvest date, the time of storage, and the input of fertilizers.

Manipulation of flavour and aroma compound sequestration and release using a glycosyltransferase with specificity for terpene alcohols.

Glycosides are an important potential source of aroma and flavour compounds for release as volatiles in flowers and fruit. The production of glycosides is catalysed by UDP-glycosyltransferases (UGTs) that mediate the transfer of an activated nucleotide sugar to acceptor aglycones. A screen of UGTs expressed in kiwifruit (Actinidia deliciosa) identified the gene AdGT4 which was highly expressed in floral tissues and whose expression increased during fruit ripening. Recombinant AdGT4 enzyme glycosylated a range of terpenes and primary alcohols found as glycosides in ripe kiwifruit. Two of the enzyme's preferred alcohol aglycones, hexanol and (Z)-hex-3-enol, contribute strongly to the 'grassy-green' aroma notes of ripe kiwifruit and other fruit including tomato and olive. Transient over-expression of AdGT4 in tobacco leaves showed that enzyme was able to glycosylate geraniol and octan-3-ol in planta whilst transient expression of an RNAi construct in Actinidia eriantha fruit reduced accumulation of a range of terpene glycosides. Stable over-expression of AdGT4 in transgenic petunia resulted in increased sequestration of hexanol and other alcohols in the flowers. Transgenic tomato fruit stably over-expressing AdGT4 showed changes in both the sequestration and release of a range of alcohols including 3-methylbutanol, hexanol and geraniol. Sequestration occurred at all stages of fruit ripening. Ripe fruit sequestering high levels of glycosides were identified as having a less intense, earthier aroma in a sensory trial. These results demonstrate the importance of UGTs in sequestering key volatile compounds in planta and suggest a future approach to enhancing aromas and flavours in flowers and during fruit ripening.

The impact of sodium nitroprusside and ozone in kiwifruit ripening physiology: a combined gene and protein expression profiling approach.

BACKGROUND AND AIMS: Despite their importance in many aspects of plant physiology, information about the function of oxidative and, particularly, of nitrosative signalling in fruit biology is limited. This study examined the possible implications of O3 and sodium nitroprusside (SNP) in kiwifruit ripening, and their interacting effects. It also aimed to investigate changes in the kiwifruit proteome in response to SNP and O3 treatments, together with selected transcript analysis, as a way to enhance our understanding of the fruit ripening syndrome. METHODS: Kiwifruits following harvest were pre-treated with 100 µm SNP, then cold-stored (0 °C, relative humidity 95 %) for either 2 or 6 months in the absence or in the presence of O3 (0·3 µL L(-1)), and subsequently were allowed to ripen at 20 °C. The ripening behaviour of fruit was characterized using several approaches: together with ethylene production, several genes, enzymes and metabolites involved in ethylene biosynthesis were analysed. Kiwifruit proteins were identified using 2-D electrophoresis coupled with nanoliquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Expression patterns of kiwifruit ripening-related genes were also analysed using real-time quantitative reverse transcription-PCR (RT-qPCR). KEY RESULTS: O3 treatment markedly delayed fruit softening and depressed the ethylene biosynthetic mechanism. Although SNP alone was relatively ineffective in regulating ripening, SNP treatment prior to O3 exposure attenuated the O3-induced ripening inhibition. Proteomic analysis revealed a considerable overlap between proteins affected by both SNP and O3. Consistent with this, the temporal dynamics in the expression of selected kiwifruit ripening-related genes were noticeably different between individual O3 and combined SNP and O3 treatments. CONCLUSIONS: This study demonstrates that O3-induced ripening inhibition could be reversed by SNP and provides insights into the interaction between oxidative and nitrosative signalling in climacteric fruit ripening.

Detection and characterization of Pseudomonas syringae pv. actinidifoliorum in kiwifruit in Spain.

AIMS: Bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae (Psa) is currently the major threat to its commercial production worldwide. In 2011, the most virulent type (Psa3) was detected for the first time in Northwest-Spain, in the province of Pontevedra. In 2013 surveys, leaves and flower buds with mild symptoms were observed in Actinidia deliciosa 'Hayward' vines in an orchard at the province of A Coruña, suggesting the presence of P. syringae pv. actinidifoliorum (Psaf). METHODS AND RESULTS: Isolates obtained from such orchard were characterized by morphological, biochemical and physiological tests, fatty acids (FA) profile and molecular tests (PCR, BOX-PCR, duplex PCR, multiplex PCR, real-time PCR, PCR-C, phytotoxins, housekeeping and effector genes). Pathogenicity tests were also carried out on plants and fruits of A. deliciosa 'Hayward' and on different cultivated plants and fruits. Results demonstrated the presence of P. syringae pv. actinidifoliorum in Spain. CONCLUSIONS: The work provides new information on the pathovar P. syringae pv. actinidifoliorum, which has only been found previously in New Zealand, Australia and France. SIGNIFICANCE AND IMPACT OF STUDY: The results are relevant for taxonomy of isolates of P. syringae from kiwifruit, especially those of low virulence not belonging to pathovar actinidiae.

Dataset on effect of biostimulants on growth and rooting of kiwifruit (Actinidia deliciosa) cuttings: from morphological and gene regulation approach.

Actinidia chinensis Planch. and A. deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson are the botanical names for the two main closely related kiwifruit species that are cultivated worldwide [1]. According to the Food and Agriculture Organisation (FAO) of the United Nation, kiwifruit is produced on 268,788 hectares of land worldwide, yielding 4,348,011 metric tonnes of fruit per year. China is the world's top producer, followed by Italy, New Zealand, Chile, and Greece, with a cumulative valuation of 2,907,580 thousand US dollars for export (http://www.fao.org/faostat/en/#data/QC). Several research using nutrient medium and other inorganic treatments on softwood cuttings for micro-propagation techniques have shown promising outcomes [2,3]. Several agricultural and horticultural crops have demonstrated significantly improved crop growth, quality, and reproduction when treated with seaweed extracts [4]. It is possible to utilise seaweed extracts to encourage cuttings from perennial fruit species, such as kiwifruit (Actinidia deliciosa), to root and flourish. Absence of a growth regulator permitted by organic methods is one of the main obstacles in kiwifruit production. Hardwood cuttings are the most popular technique of clonally reproducing kiwifruit, and the cuttings' ability to root depends on the application of synthetic auxins, which is not allowed in organic agriculture. Therefore, alternative biostimulants have been used to promote the rooting of kiwifruit cuttings in this study. For six hours, the cuttings in this investigation were submerged in base dipping solutions containing 1, 5, 10, and 50 % of G Sap (Gracilaria edulis), K Sap (Kappaphycus alvarezii), AN (Ascophyllum nodosum), EM (Ecklonia maxima), HA (Humic acid), and control (water). After that, for a period of six months, the treatments of G Sap, K Sap, AN, EM, HA, and control were applied (at the rate of 50 ml of solutions) to the potted cuttings at intervals of fifteen days. The dataset provided the data of the rooting percent in all the kiwifruit cultivars, namely 'Monty', 'Abott', 'Hayward', 'Allison' and 'Bruno' (P ≤ 0.01), shoot and root growth parameters including leaf number per cutting, number of roots per cutting, number of branches, plant height, shoot diameter, root length, root diameter and root weight with the application of seaweed extracts. Also data of pigments (chlorophyll a, chlorophyll b and total carotenoids), metabolites (total carbohydrates and soluble phenols) and electrolyte leakage were collected after the treatments. Data of four root promoting candidate genes (GH3-3, LBD16, LBD29 and LRP1) were also described which indicated the influence of the biostimulants on the cuttings. The application of seaweed extracts resulted in a positive increase in all shoot and root growth parameters, including the number of leaves per cutting, the number of roots per cutting, the number of branches, plant height, shoot diameter, root length, root diameter, and root weight (P ≤ 0.05). In comparison to the control cuttings, the seaweed extract-treated cuttings showed significantly greater levels of pigments (such as chlorophyll a, chlorophyll b, and total carotenoids), metabolites (such as total carbohydrates and soluble phenols), and reduced electrolyte leakage. Various treatments (1, 5 and 10% solutions of G Sap, K Sap, AN, EM, HA and control) gave positive impact on nutrient parameters of kiwifruit cultivar 'Hayward'. Moreover, the relative positive expressions of root inducing genes (GH3-3, LBD16, LBD29 and LRP1) was observed in leaves and roots of cultivar 'Hayward' by qRT-PCR after treatment with G Sap, K Sap, AN, EM, HA @ 10 % and control. Thus, it can be said that seaweed extract and humic acid are good substitutes for synthetic hormones in encouraging kiwifruit cuttings to root and flourish.

Evaluation of Various Inoculation Methods on the Effect of Beauveria bassiana on the Plant Growth of Kiwi and on Halyomorpha halys Infestation: A Two-Year Field Study.

In this study, the bioinsecticidal action of a commercial formulation with Beauveria bassiana was evaluated on the new sucking pest in Greece: Halyomorpha halys, of the kiwifruit. Additionally, the biostimulant potential of the same formulation was studied on kiwi growth. The application was performed in three different ways in a commercial field of kiwi crop A. deliciosa "Hayward" field in Arta, Greece: (i) trunk spray, (ii) root injection, and (iii) trunk inoculation. During the 2 years seasons of the experiment, weekly measurements of the H. halys population were determined. The insect is sucking plants nutrients; therefore, the total chlorophyll content in the leaves of the treatments was recorded weekly. In addition, the percentage of infested kiwifruits was estimated at the end of the experiment. Moreover, to study the biostimulant potential of the formulation, growth measurements on stems and leaves were performed during the experiment. Finally, at the kiwi harvest point, the fruit biomass, dimensions, and weight were obtained, and the leaves' proline content was evaluated. The results encourage us to further study this EPF formulation as the bioinsecticidal effect was noted by the reduction in H. halys population, and biostimulant action was perceived by the higher plant biomass.

Occurrence of Pseudomonas syringae pvs. actinidiae, actinidifoliorum and Other P. syringae Strains on Kiwifruit in Northern Spain.

Pseudomonas syringae pv. actinidiae (Psa), the agent causing bacterial canker of kiwifruit, has been present in the Principality of Asturias (PA), Northern Spain, since 2013, although with restricted distribution. In this study, 53 strains collected in kiwifruit orchards in PA during the period 2014-2020 were characterized by a polyphasic approach including biochemical and phylogenetic analysis. Thirty-three strains, previously identified by PCR as Psa, have been found to be a homogeneous group in phylogenetic analysis, which seems to indicate that there have been few introductions of the pathogen into the region. Two strains were confirmed as P. syringae pv. actinidifoliorum (Pfm), so this is the first report of Pfm in the PA. The remaining 18 strains were found to be close to P. avellanae and P. syringae pv. antirrhini or to strains described as Pfm look-alikes. Pathogenicity tests carried out on peppers with a selection of strains have shown that both Psa and Pfm caused clear damage, while the 18 atypical strains caused variable lesions. It would be necessary to carry out pathogenicity testing of atypical strains on kiwifruit plants to study the role of these strains in the kiwifruit pathosystem to evaluate their pathogenic potential in this crop.

Kiwifruit (Actinidia deliciosa) aqueous extract improves hyperglycemia, testicular inflammation, apoptosis, and tissue structure induced by Streptozotocin via oxidative stress inhibition.

Diabetes mellitus (DM) is a well-known hyperglycemic metabolic condition identified by oxidative stress and biological function disruption. Kiwifruit is a valuable source of polyphenols and vitamin C with great antioxidant, nutritional, and health-promoting effects. Therefore, this study was initiated to explore the antioxidant and anti-hyperglycemic effects of kiwifruit aqueous extract (KFE) against oxidative injury and testis dysfunction in rats with diabetes. Twenty-four male Wistar Albino rats (160-170 g) were divided into four groups: Group 1 served as the control, Group 2 supplemented orally with kiwifruit extract (KFE; 1 g/kg/day) for one month, Group 3 was treated with a single streptozotocin dose (STZ; 50 mg/kg ip), and Group 4 where the diabetic rats were administered with KFE, respectively. According to the results, the GC-MS analysis of KFE revealed several main components with strong antioxidant properties. In diabetic rats, lipid peroxidation and hyperglycemia were accompanied by perturbations in hormone levels and sperm characteristics. Antioxidant enzymes, glutathione content, aminotransferase, phosphatase activities, and protein content were decreased. Furthermore, histology, immunohistochemical PCNA expression, and histochemical analysis of collagen, DNA, RNA, and total protein. were altered in rat testis sections, supporting the changes in biochemistry. Furthermore, diabetic rats supplemented with KFE manifested considerable amendment in all the tested parameters besides improved tissue structure and gene expressions (NF-kB, p53, IL-1ß, Bax, IL-10, and Bcl2) relative to the diabetic group. In conclusion, KFE has beneficial effects as it can improve glucose levels and testis function, so it might be used as a complementary therapy in DM.