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Inadequate levels of monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids have been reported as a risk factor for neurodegenerative diseases, including Alzheimer's disease. Avocado oil (Persea americana Mill., Laucaceae) represents a source of bioactive compounds with a relative abundance of omega-3, omega-6 polyunsaturated, and omega-9 monounsaturated fatty acids. The present study investigated the effects of extra-virgin avocado oil on the D-galactose-induced Alzheimer's disease model in ovariectomized Wistar rats. The cognitive dysfunctions were induced by D-galactose administration (150 mg.kg−1 i.p) and/or ovariectomy in 54 female rats for 70 days. The rats were concomitantly treated with extra-virgin avocado oil (0.25, 0.5, and 1 mL.kg−1, p.o), donepezil (1 mg.kg−1, p.o), and estradiol valerate (1 mg.kg−1, p.o). Memory disorders were evaluated using the Object Recognition, Y-Maze, and Morris water maze tests. Some biochemical and histological parameters regarding memory function were evaluated on hippocampus homogenate and tissue. D-galactose administration and ovariectomy significantly induced learning and memory impairments, decreased relative hippocampal weight (p < 0.001), the levels of acetylcholine (p < 0.001), glutamate (p < 0.001), reduced glutathione (p < 0.001), catalase (p < 0.05), and superoxide dismutase (p < 0.001) activities, and an increase (p < 0.001) in the levels of methylglyoxal, malondialdehyde, and nitrites. The treatment with extra-virgin avocado oil at all tested doses reversed or prevented the negative effects induced by ovariectomy and/or by D-galactose. Taken together, these results suggest that avocado oil possesses neuroprotective properties and can be consumed or supplemented to prevent the onset of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

The avocado crop is relevant for its economic importance and because of its unique evolutionary history. However, there is a lack of information regarding the molecular processes during the defense response against fungal pathogens. Therefore, using a genome-wide approach in this work, we investigated the transcriptional response of the Mexican horticultural race of avocado (Persea americana var. drymifolia), including miRNAs profile and their possible targets. For that, we established an avocado–Fusarium hydroponic pathosystem and studied the response for 21 days. To guarantee robustness in the analysis, first, we improved the avocado genome assembly available for this variety, resulting in 822.49 Mbp in length with 36,200 gene models. Then, using an RNA-seq approach, we identified 13,778 genes differentially expressed in response to the Fusarium infection. According to their expression profile across time, these genes can be clustered into six groups, each associated with specific biological processes. Regarding non-coding RNAs, 8 of the 57 mature miRNAs identified in the avocado genome are responsive to infection caused by Fusarium, and the analysis revealed a total of 569 target genes whose transcript could be post-transcriptionally regulated. This study represents the first research in avocados to comprehensively explore the role of miRNAs in orchestrating defense responses against Fusarium spp. Also, this work provides valuable data about the genes involved in the intricate response of the avocado during fungal infection. [ABSTRACT FROM AUTHOR]

The increasing incidence of heat stress due to global climate change poses a significant challenge to avocado (Persea americana) cultivation, particularly in regions with intense solar radiation. This review evaluates sun protection strategies, focusing on the efficacy of different sunscreen products such as kaolin, titanium dioxide, and calcium oxide in mitigating thermal stress in avocado trees. The application of these materials was shown to reduce leaf and fruit surface temperatures, improve photosynthetic efficiency, and enhance fruit quality by preventing sunburn and dehydration. Despite these benefits, challenges remain, including the optimal timing and dosage of application, and the potential residue impacts on fruit marketability. The review emphasizes the need for ongoing research to develop more effective formulations and to integrate these sun protection strategies with other agronomic practices. The role of extension services in educating producers about the proper use of these technologies is also highlighted as crucial for the successful adoption of sun protection measures in avocado farming. [ABSTRACT FROM AUTHOR]

Carbohydrate levels are important regulators of the growth and yield of tree crops. Current methods for measuring foliar carbohydrate concentrations are time consuming and laborious, but rapid imaging technologies have emerged with the potential to improve the effectiveness of tree nutrient management. Carbohydrate concentrations were predicted using hyperspectral imaging (400–1000 nm) of leaves of the evergreen tree crops, avocado, and macadamia. Models were developed using partial least squares regression (PLSR) and artificial neural network (ANN) algorithms to predict carbohydrate concentrations. PLSR models had R2 values of 0.51, 0.82, 0.86, and 0.85, and ANN models had R2 values of 0.83, 0.83, 0.78, and 0.86, in predicting starch, sucrose, glucose, and fructose concentrations, respectively, in avocado leaves. PLSR models had R2 values of 0.60, 0.64, 0.91, and 0.95, and ANN models had R2 values of 0.67, 0.82, 0.98, and 0.98, in predicting the same concentrations, respectively, in macadamia leaves. ANN only outperformed PLSR when predicting starch concentrations in avocado leaves and sucrose concentrations in macadamia leaves. Performance differences were possibly associated with nonlinear relationships between carbohydrate concentrations and reflectance values. This study demonstrates that PLSR and ANN models perform well in predicting carbohydrate concentrations in evergreen tree-crop leaves. [ABSTRACT FROM AUTHOR]

Heilipus lauri Boheman, the avocado seed weevil, is recorded for the first time in the Mixe Zone of Oaxaca, Mexico. This insect is already found in avocado orchards in other locations of Oaxaca, such as Santa María Alotepec and Santa María Tepantlali. [ABSTRACT FROM AUTHOR]

The alpha, beta, and gamma diversity of Braconidae was analyzed in three avocado orchards (Piedra Rajada, the Guardián, and Montitlán) in Colima, Mexico, from monthly samplings from September 2016 to June 2017. In total, 171 braconids were collected. These included 21 genera (nine are new records for Colima) and 28 morphospecies that corresponded to 73% of the expected richness in the study area. The orchard in Piedra Rajada had the highest number of species and diversity. The update of the Braconidae genera for the state of Colima, Mexico is presented. [ABSTRACT FROM AUTHOR]

Jalisco is one of the main areas in Mexico that produces avocados (Persea americana Miller), and the adults of Euphoria basalis (Gory & Percheron) have been detected on avocado inflorescences where they feed and cause the flowers to fall prematurely. To our knowledge, this is the first report of the association of this species with P. americana trees in Mexico. [ABSTRACT FROM AUTHOR]

Avocado (Persea americana Mill.) cultivation has spread to many countries from the tropics to the Mediterranean region, where avocado crops commonly face water shortages and diseases, such as white root rot (WRR) caused by Rosellinia necatrix. The use of drought- and WRR-tolerant rootstocks represents a potential solution to these constraints. In this research, water relations and the morpho-physiological response of avocado 'Hass' grafted on two selections of R. necatrix-tolerant rootstocks (BG48 and BG181) were evaluated under well-watered (WW) and at two soil-water-availability conditions (WS, ~50% and ~25% field capacity). Under WW, scion water use was markedly affected by the rootstock, with BG48 displaying a water-spender behavior, showing higher water consumption (~20%), plant transpiration rates (~30%; Eplant) and leaf photosynthetic rates (~30%; AN) than BG181, which exhibited a water-saving strategy based upon a trade-off between leaf-biomass allocation and tight stomatal control of transpiration. This strategy did not reduce biomass, with BG181 plants being more water use efficient. Under WS, BG48 and BG181 exhibited a drought-avoidance behavior based on distinct underlying mechanisms, but increases in leaf mass area (~18–12%; LMA), and decreases in Eplant (~50–65%), plant hydraulic conductance (~44–86%; Kh) and leaf water potential (~48–73%; Ψw) were observed in both rootstocks, which aligned with water stress severity. After rewatering, photosynthetic rates fully recovered, suggesting some ability of these rootstocks to withstand water stress, enabling the 'Hass' variety to adapt to region-specific constraints. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare two methods of avocado graft development to determine levels of indirect resistance to Phytophthora cinnamomi. It was found that the etiolated graft method presented faster growth and greater uniformity in the lesions generated by the pathogen, which allowed for discrimination of resistance levels among genotypes. Additionally, the process of seed conditioning and production of West Indian avocado rootstocks in Colombia is described, as well as the vegetative propagation method of two avocado genotypes. A study on the development of Hass and Duke-7 avocado shoots using different methods is also presented, as well as another study on the development of the disease caused by the P. cinnamomi pathogen in avocado grafts. Finally, the potential use of avocado germplasm as rootstocks for soil stress conditions is mentioned, and other aspects related to avocado cultivation are discussed. [Extracted from the article]

Postharvest assessment of 'Hass' avocado fruit ripening is frequently monitored by the fruit texture as it changes from hard to soft and 'buttery'. This large change in texture is easily measured, commonly by a penetrometer after removal of a small area of skin or by a whole-fruit compression measurement. The penetrometer is slow and destructive whereas the compression measurement is rapid and may be considered as non-destructive depending on the method. Investigation of the two methods on the same batch of fruit reveals information pertinent to the understanding of fruit ripening — beyond the simple provision of a numerical assessment of the progress of ripening. Monitoring of fruit under drying conditions revealed the role that fruit turgor plays in the compression measurement, and how it contributes to our understanding of the numerical values. Likewise, the observed variation among individual fruit ripening times may mean that averaged values are misleading, suggesting that fruit ripening takes longer than it actually does. The key element in the fruit-to-fruit variability was the pre-climacteric period before the fruit ripened. Additional penetrometer measurements of five regions of the fruit flesh for each fruit assessed quantified differences in mesocarp softening within the fruit. [ABSTRACT FROM AUTHOR]

Avocado seed contains 64% of the phenolic compounds of the whole fruit. This makes avocado seed a potential candidate for the development of treatments for different illnesses, including obesity (the major risk factor for metabolic disorders). The aim of this study was to investigate the effects of avocado seed powder on high-fat diet-induced obesity in rats. Sprague Dawley rats (16 rats) were fed a high-fat diet for 10 weeks. After 10 weeks, the rats were assigned into two groups of eight animals each and were fed either a high-fat diet (HFD; control group) or a high-fat diet containing avocado seed powder (HFD-A; treatment group) for 6 weeks. Animals were weighed weekly, and weekly weight gain was determined. Animals in the treatment (avocado seed) group showed significantly lower body weight gain (7.8 ± 9.63 g) than animals in the control group (33.9 ± 10.84 g) at the end of this study. The treatment group presented with lower triglycerides than the control, with LDL and HDL comparable to the control group. Avocado seed powder showed potential to reduce obesity in rats fed a high-fat diet. Avocado seed can therefore be investigated further as a potential anti-obesity nutraceutical. [ABSTRACT FROM AUTHOR]

Avocado seed contains 64% of the phenolic compounds of the whole fruit. This makes avocado seed a potential candidate for the development of treatments for different illnesses, including obesity (the major risk factor for metabolic disorders). The aim of this study was to investigate the effects of avocado seed powder on high-fat diet-induced obesity in rats. Sprague Dawley rats (16 rats) were fed a high-fat diet for 10 weeks. After 10 weeks, the rats were assigned into two groups of eight animals each and were fed either a high-fat diet (HFD; control group) or a high-fat diet containing avocado seed powder (HFD-A; treatment group) for 6 weeks. Animals were weighed weekly, and weekly weight gain was determined. Animals in the treatment (avocado seed) group showed significantly lower body weight gain (7.8 ± 9.63 g) than animals in the control group (33.9 ± 10.84 g) at the end of this study. The treatment group presented with lower triglycerides than the control, with LDL and HDL comparable to the control group. Avocado seed powder showed potential to reduce obesity in rats fed a high-fat diet. Avocado seed can therefore be investigated further as a potential anti-obesity nutraceutical.

A previous study found that mass transfer occurring during the osmotic dehydration (OD) process. This phenomena is possible causing modification in physicochemical properties; therefore, understanding the OD effect on quality attributes is important. This research aimed to study the impact of sucrose concentration and immersion time on the kinetics of mass transfer and the physicochemical properties of avocado (Persea americana var. Miki) during the OD process. The samples were immersed in a sucrose solution (45, 55 and 65 ° Brix) for up to 300 min, then the mass transfer parameter and physicochemical properties were evaluated. The results showed that the highest rate of water removal (WR) was -0.037 g.g-1.h-1 using the 55 ° Brix solution, which also led to an increase in the soluble solid gain (SSG) value to 0.0126 g.g-1.h-1, while the highest WR/SSG ratio was obtained after 180 min of immersion using 65 ° Brix (2.451). A 2nd-order polynomial model accurately describes avocado mass transfer kinetics and their relationship to physicochemical properties. The model showed the best adjustment for WR, SSG, and weight loss (WL), as pointed out by R2 = 0.9671, 0.8968 and 0.9573, respectively. WR has a negative effect on firmness (R2 = 0.9278), vitamin C (R2 = 0.9349), and total fat (R2 = 0.8954). The uptake of sucrose correlated with decrease of vitamin C (R2 = 0.9391), whereas WL also affected the loss of total fat (R2 = 0.8288). The OD process modified the chroma of the avocado by reducing lightness, increasing greenness and yellowness, and yet protecting the flesh from the browning effect. Overall, this study provides insights into the relationship between mass transfer and physicochemical properties, and it is useful to predict the final condition of the osmo-avocado before subsequent processes. [ABSTRACT FROM AUTHOR]

BACKGROUND: Avocado fruit is rich in xanthophylls, which have been related to positive effects on human health. Xanthophyl acetyltransferases (XATs) are enzymes catalyzing the esterification of carboxylic acids to the hydroxyl group of the xanthophyll molecule. This esterification is thought to increase the lipophilic nature of the xanthophyll and its stability in a lipophilic environment. Studies on XATs in fruits are very scarce, and no studies had been carried out in avocado fruit during postharvest. The objective of this work was to investigate the changes in the expression of genes encoding XAT, during avocado fruit ripening. RESULTS: Avocado fruits were obtained from a local market and stored at 15 °C for 8 days. The fruit respiration rate, ethylene production, and fruit peel's color space parameters (L*, a*, b*) were measured during storage. Fruit mesocarp samples were taken after 1, 3, 5, and 7 days of storage and frozen with liquid nitrogen. Total RNA was extracted from fruit mesocarp, and the quantification of the two genes designated as COGE_ID: 936743791 and COGE_ID: 936800185 encoding XATs was performed with real‐time quantitative reverse transcription polymerase chain reaction using actin as a reference gene. The presence of a climacteric peak and large changes in color were recorded during postharvest. The two genes studied showed a large expression after 3 days of fruit storage. CONCLUSIONS: We conclude that during the last stages of ripening in avocado fruit there was an active esterification of xanthophylls with carboxylic acids, which suggests the presence of esterified xanthophylls in the fruit mesocarp. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Nowadays, a large number of aromatic and medicinal plants possess highly significant bioproperties, with numerous applications in medicine, pharmacy, cosmetology, and agriculture. This work aimed to conduct a phytochemical screening and assay of phytomarkers with biopharmaceutical potential and to assess the antioxidant and antibacterial activity of Persea americana Mill. kernel extracts in vitro. P. americana plant samples were collected in May 2017 in Kinshasa. Three standard strains were selected namely Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, and Pseudomonas aeroginosa ATCC 9027 for microbiological assays. The phytomarker assay was used to detect total polyphenols, and the antibacterial activity was determined using the solid diffusion method on the Mueller Hinton medium to establish the minimal inhibitory concentration. Antioxidant activity was evaluated by the DPPH, ABTS, and Phosphomolybdate techniques. The findings showed that P. americana kernels contain secondary metabolites such as flavonoids, polyphenols, alkaloids, tannins, and triterpenoids, which may confer interesting biological activities. Quantitative phytomarker analysis of P. americana extracts showed a concentration of 69.70±3.07 mg/QE of total polyphenols and 27.53±1.15 mg/QE of flavonoids. All the extracts tested had low antibacterial activity against the three strains tested. However, the methanolic extract showed better antioxidant activity. In view of the IC50 values of our various fractions, it is clear that P. americana kernels possess interesting antioxidant properties. [ABSTRACT FROM AUTHOR]

Changes in vegetation and land use alter the biogeochemical cycles of soil C and N, as a result of agricultural practices that alter soil quality and function. Adopting sustainable agricultural practices improves soil health by increasing its capacity to store C in the long term. The objective of this study was to evaluate the content and stocks of C and N and the C:N ratio, under different land uses in an Andosol. Four composite soil samples were collected in a pine-oak forest, conventional avocado, organic avocado and organic macadamia soil uses at 0-20 and 20-40 cm soil depths (n=32). The total C content was determined by the Walkley and Black method (Woerner, 1989), the total N by the Kjeldahl method with the Velp Scientifica's UDK159 model equipment (Bremner and Mulvaney 1982). In order to detect significant differences, a two factor analysis of variance (ANOVA) was applied C (%), N (%), SOC (Mg ha-1 ), Nt (Mg ha-1 ) and C:N ratio variables. When applied, a Tukey comparison of means (p≤0.05) was performed. The results indicate that conventional avocado land use presented the highest C and N content at both soil depths (C: 9.22 and 7.32%, N: 0.70 and 0.40%), while the C:N ratio was higher in the forest land use in the first depth (14.5) and higher in the organic avocado land use in the second soil depth (25.8). The stock of SOC varied from 65.27 to 267.30 (Mg ha-1 ) and the Nitrogen from 4.61 to 14.61 (Mg ha-1 ). The C:N ratio showed significant variations between land uses, specifically in the first depth it ranged from 10.33 (O. Macadamia) to 14.51 (Forest), while in the second depth it varied from 13.09 (Conventional) to 25.83 (O avocado). The pine-oak forest, organic avocado and organic macadamia systems, with the smallest reseivors, were statistically similar only in C content, while the conventional system, with the largest stocks, was differente in C and N content. The change in land use from forest to agricultural caused a significant effect on the carbon and nitrogen content and the stocks in the Andosol soil, which may be attributes to the different agricultural applied practices such as pruning, pesticides and fertilization used in the organic and conventional regimes, respectively. The C:N ratio indicates that mineralization rates decrease as depth increases because the quantity and quality of soil organic matter also decreases. Specifically, the conventional avocado practice compared to organic avocado and macadamia practices maximized crop yields. [ABSTRACT FROM AUTHOR]

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• Persea americana, Curcuma longa and Allium sativum extracts showed anti-cercariae activity. • Methanol extracts of Persea americana bark and Curcuma longa exhibited the most potent scavenging activity. • Persea americana, Curcuma longa and Allium sativum extracts exhibited potent anti-inflammatory activity. • Plant extracts showed low toxicity on kidney Vero cells and murine macrophage cell lines. Schistosomiasis is a devastating parasitic infection, particularly in Sub-Saharan Africa. Despite the use of Praziquantel, the elimination of schistosomiaisis remains a challenge. The use of medicinal plant as treatment in disease endemic regions has provided a basis for investigating the antischistosomal properties of the plants-derived materials. This study therefore stands as a starting point for the search of new drugs against schistosomiasis. This study sought to evaluate the cercaricidal activity of methanolic extracts of Persea americana, Curcuma longa and Allium sativum. Twenty cercariae were exposed to plant extract concentrations ranging from 3.9 to 103 µg/ml. The antioxidant study was carried out using DPPH, ABTS, and FRAP assays. Anti-inflammatory activity was conducted by assessing the potential through albumin denaturation inhibition assay. The in vitro safety and phytochemical composition of plant extracts were also assessed. Cercaricidal tests revealed significant anti-cercariae activity of plant extracts at sublethal concentrations with LC 50 values ranging from 7.67 ± 3.40 to 56.07 ± 2.53 µg/ml with C. longa extract being the most potent cercaricidal. Antioxidant activity of plant extracts revealed that methanol extracts of P. americana bark and C. longa have the most potent antioxidant scavenging activities with SC 50 values ranging from 91.47 ± 5.83 to 138.75 ± 5.73 µg/ml. Anti-inflammatory analysis showed that plant extracts exhibited most potent anti-inflammatory activity by inhibiting protein denaturation. At 125 µg/ml, A. sativum, C. longa, P. americana root, bark, stem and leaf extracts showed 33.89, 108.26, 93.37, 108.18, 93.96 and 118.15 % inhibitions respectively, while the standard drug Diclofenac sodium (125 µg/ml) produced 24.67 % inhibition. Plant extracts also showed low toxicity on kidney Vero cells and murine macrophage cell lines with IC 50 values ranging between 132.15 ± 40.66 and 549.3 ± 43.70 µg/ml. The phytochemical composition of plant extracts shows that the plants are rich in at least five of saponins, cardiac glycosides, phenolics, flavonoids, alkaloids and tannins. These results suggest that methanolic extract of C. longa and P. americana showed a potent activity against S. mansoni cercariae with potent antioxidant scavenging activities and can mitigate the inflammatory effect of schistosome eggs within egg-infested tissue, combating the devastating effect of S. mansoni infection. [ABSTRACT FROM AUTHOR]

Summary: Four criconematid populations were uncovered in three avocado orchards in Homestead region, Miami-Dade County, Florida, USA, with three of them in relatively high densities. Two of the populations were identified as Criconema mutabile (Taylor, 1936) Raski & Luc, 1985 and Mesocriconema basili (Jairajpuri, 1964) Loof & De Grisse, 1989, whereas the other two populations were identified as Criconemoides sp. and Ogma sp. The identification of the nematodes was based on morphological analysis and C. mutabile was also confirmed based on the 28S rRNA gene. The molecular data of M. basili (18S and 28S rRNA genes) are presented for the first time and phylogenetic trees based on the genes are provided illustrating the relationships of M. basili with other criconematid species. This study further reports the presence of C. mutabile and M. basili for the first time in Florida, USA, and the association of the latter species with avocado rhizosphere. [ABSTRACT FROM AUTHOR]

Background and Aims Plant water status is important for fruit development, because many fleshy fruits contain large amounts of water. However, there is no information on vascular flows of Persea americana 'Hass' avocado. The aims of this research were to explore the impact of drought stress on the water relationships of the 'Hass' avocado plant and its fruit growth. Methods Well-watered and water-stressed 'Hass' avocado plants were compared. Over 4 weeks, water flows through the shoot and fruit pedicel were monitored using external sap flow gauges. Fruit diameter was monitored using linear transducers, and stomatal conductance (g s), photosynthesis (A) and leaf and stem water potentials (Ѱleaf and Ѱstem) were measured to assess the response of the plants to water supply. Key Results In well-watered conditions, the average water inflow to the shoot was 72 g day−1. Fruit water inflow was 2.72 g day−1, but there was water loss of 0.37 g day−1 caused by the outflow (loss back into the tree) through the vascular tissues and 1.06 g day−1 from the fruit skin. Overall, fruit volume increased by 1.4 cm3 day−1. In contrast, water flow into fruit of water-stressed plants decreased to 1.88 g day−1, with the outflow increasing to 0.61 g day−1. As a result, increases in fruit volume were reduced to 0.4 cm3 day−1. The values of A , g s and sap flow to shoots were also reduced during drought conditions. Changes in the hourly time-courses of pedicel sap flow, fruit volume and stem water potential during drought suggest that the stomatal response prevented larger increases in outflow from the fruit. Following re-watering, a substantial recovery in growth rate was observed. Conclusions In summary, a reduction in growth of avocado fruit was observed with induced water deficit, but the isohydric stomatal behaviour of the leaves helped to minimize negative changes in water balance. Also, there was substantial recovery after re-watering, hence the short-term water stress did not decrease avocado fruit size. Negative impacts might appear if the drought treatment were prolonged. [ABSTRACT FROM AUTHOR]

During ripening, 'Hass' avocado skin changes from green to purple/black. Low-temperature storage with a controlled atmosphere (CA) is the most widely used method for avocado storage; however, few studies have simulated this technology and considered the days of regular air (RA) storage prior to CA storage. Herein, the effect of delaying the storage of 'Hass' avocado (>30% dry matter) in a CA was examined. Long-term storage conditions (5 °C for 50 days) corresponded to (i) regular air storage (RA), (ii) CA (4 kPa O2 and 6 kPa CO2) and (iii) 10 days in RA + 40 days in a CA and (iv) 20 days in RA + 30 days in a CA. Evaluations were performed during storage and at the ready-to-eat (RTE) stage. Skin color remained unchanged during storage, but at the RTE stage, more color development was observed for fruits stored under CA conditions, as these fruits were purple/black (>50%). At the RTE stage, the anthocyanin content increased, and compared to fruit under RA, fruit under a CA contained a five-fold greater content. A 20-day delay between harvest and CA storage increased the fruit softening rate and skin color development after cold storage, reducing the effectiveness of CA as a postharvest technology for extending storage life. [ABSTRACT FROM AUTHOR]

The productivity of many tree crops is limited by low yield, partly due to high rates of fruitlet abscission during early fruit development. Early studies suggested that cross-pollinated fruitlets may be selectively retained during fruit development, although paternity testing of fruitlets to test this hypothesis was technically challenging. We used MassARRAY genotyping to determine the effects of pollen parentage on fruitlet retention and fruit quality of Hass avocado. We identified the paternity of abscised and retained fruitlets at 6 and 10 weeks, and mature fruit at 36 weeks, after peak anthesis. We measured the embryo mass, pericarp mass, total mass and nutrient concentrations of fruitlets, and the seed mass, flesh mass, total mass, diameter, length, nutrient concentrations and fatty-acid composition of mature fruit. The percentages of progeny on the tree that were cross-fertilised increased from 4.6% at 6 weeks after peak anthesis to 10.7% at fruit maturity. Only 1.0% of freshly abscised fruitlets on the ground at 10 weeks after peak anthesis were cross-pollinated even though 6.5% of retained fruitlets on the tree were cross-pollinated. At this stage, cross-pollinated fruitlets had similar nutrient concentrations to self-pollinated fruitlets, but they had higher total contents of P, K, Al, Ca, Fe, Mn and Zn due to having greater fruitlet mass. At maturity, cross-pollinated fruit were 6% heavier and had 2% greater diameter than self-pollinated fruit, without significant differences in flesh nutrient concentrations or fatty acid composition. The results demonstrate that Hass avocado trees selectively retain cross-pollinated fruitlets, which are larger than self-pollinated fruitlets and ultimately produce larger mature fruit. Avocado growers can increase fruit size and yield by improving the opportunities for cross-pollination, possibly by closely interplanting type A and type B cultivars and introducing more beehives into orchards. [ABSTRACT FROM AUTHOR]

The study investigates the comparative analysis of the phytochemical composition of Dacryodes edulis and Persea Americana seeds collected from Ikot Osurua, Ikot Ekpene Local Government Area of Akwa Ibom State, using standard analytical procedures. The phytochemical compositions of Dacryodes edulis and Persea Americana seeds exhibit unique variations compared to other plant species. Notably, the presence of alkaloids, saponins, flavonoids, tannins, and hydrogen cyanide in these seeds demonstrates distinctive phytochemical profiles, as indicated in D. edulis and P. Americana respectively: Alkaloids % (18.215+0.276) and (21.511+0.157), saponins % (14.120+0.170) and (19.622+0.120), flavonoids (3.690+0.270) and (3.590+0.014), tannins (3.315+0.134) and 0.947+0.025), and hydrogen cyanide (1.660+0.100) and (14.225+0.110). The paper reveals the presence of various phytochemicals in both plant species and different concentrations of alkaloids, saponins, flavonoids, tannins, and hydrogen cyanide in the two seeds, with some concentrations falling below, exceeding, or meeting FAO/WHO standards. The results demonstrate that the concentrations of these phytochemicals vary from the FAO/WHO standards, indicating their potential for pharmaceutical use and defense against pathogens. In conclusion, the study highlights the potential of D. edulis and P. Americana as sources of valuable supplements. [ABSTRACT FROM AUTHOR]

The ethanol extract of Persea americana seeds was found to inhibit the development of estrogen-dependent conditions in female Wistar rats, suggesting the ability of its secondary metabolites to interact with estrogen receptors (ERs), either as partial agonists or as antagonists. To test this hypothesis, the abovementioned extract was assessed for its ability to mimic and/or antagonize estradiol effects. Two experiments were conducted in ovariectomized (OVX) rats: (1) animals were treated with estradiol valerate (E2V; 1 mg/kg) or P. americana at doses of 25 and 50 mg/kg; (2) animals were treated with E2V alone (0.75 mg/kg) or in combination with P. americana at the abovementioned doses. Treatments were given orally for 3 days and animals were sacrificed for biochemical and histological analyses of the uterus and vagina. When administered alone, P. americana did not change the histomorphology of both organs (uterus and vagina). In combination with E2V, P. americana decreased uterine weight [30 % decrease (p<0.001) at 25 mg/kg and 24 % (p<0.01) at 50 mg/kg] and epithelium height (37 % decrease). This was associated with decreased estradiol levels (at least 86 % decrease, p<0.001) in the uterus. Similarly, vagina epithelium height decreased by at least 34 % (p<0.05) when E2V was co-administered with P. americana. The seed extract of P. americana contains ER antagonist secondary metabolites accounting for its ability to inhibit the development of estrogen-dependent conditions in female rats. [ABSTRACT FROM AUTHOR]

Abstract The fungus Colletotrichum gloeosporioides, which is the causal agent of anthracnose disease in green-skinned avocados, is responsible for significant postharvest fruit losses. In this context, strategies should be considered to avoid this problem. The use of essential oil (EO) can represent an alternative to contribute to antifungal activity, avoiding the use of chemical products, as their indiscriminate use can have harmful effects on human health. It is known that essential oil (EO) may exhibit antifungal activity and can be used as an alternative to chemical products. Therefore, the potential of using Lippia sidoides EO to control this fungus was investigated through in vitro evaluation (MIC and EC50) on C. gloeosporioides isolated from avocados. Furthermore, the potential of incorporating this oil with carboxymethylcellulose (CMC) for postharvest treatment in avocados was assessed in vivo to control anthracnose and maintain their physicochemical and sensory quality. The EO from L. sidoides demonstrated a MIC of 125 μl L−1 and an EC50 of 46.83 μl L−1 against this pathogen. The results indicated that the CMC edible coating associated with L. sidoides EO exhibited a positive effect on fruit quality during cold storage. In terms of sensory aspects, avocados treated with L. sidoides EO associated with CMC showed improved appearance compared to the control treatment. These findings suggest that L. sidoides EO has potential in the postharvest treatment of avocados. Additionally, these results are significant and unprecedented for this crop, as research on the postharvest effects of incorporating this EO with edible coatings in avocados is still limited. Graphical Abstract

Avocado root rot caused by Phytophthora cinnamomi is a major disease of the crop, management of which can be accomplished, partially, by reducing the amount of the pathogen inoculum in the soil. Boron is known to have fungicidal properties and has been used in controlling plant diseases. Although boron at a concentration of 1 μg mL−1 led to increased mycelial growth of P. cinnamomi, increasing the dose rate to 10 μg mL−1 decreased colony diameter; no mycelial growth occurred at 1000 μg mL−1. In the absence of inoculation with P. cinnamomi or treatment with boron (negative controls), avocado seeds germinated and emerged healthy, whereas no germination occurred in seeds of the positive control (inoculated with P. cinnamomi; no boron) treatment, or seeds inoculated with P. cinnamomi and treated with different concentrations of boron. Seeds treated with 500 μg mL−1 boron were more severely infected with P. cinnamomi than the positive controls, but seed infectivity of the pathogen decreased with increasing dose rates of boron. Although little fresh roots growth was observed even in the roots of the positive control seedlings (inoculated with P. cinnamomi and not treated with boron), almost no fresh roots formed on boron-treated plants, while negative control seedlings (non-inoculated with P. cinnamomi, not treated with boron) formed abundant fresh roots. However, as the applied boron dose increased, there was a decrease in the severity of root crown rot of the seedlings. All P. cinnamomi isolates were sensitive to mefenoxam with EC50 values between 0.002 and 0.3 μg mL−1. [ABSTRACT FROM AUTHOR]

Seaweed extracts are proven to increase productivity in many agricultural crops, but there is limited research on their use in avocado production. Therefore, we evaluated the effectiveness of a seaweed extract from Durvillaea potatorum and Ascophyllum nodosum on avocado yield, revenue and post-harvest fruit quality in a series of field experiments in Australia, and on seedling root growth in a pot experiment. The field experiments were conducted on commercial farms across three different locations in northern Queensland over four years and utilised avocado trees with different ages, cultivars (Hass and Shepard) and inoculum pressures from Phytophthora cinnamomi. Results showed that the application of the seaweed extract by fertigation significantly improved avocado yield (kg fruit per tree) by 38%, fruit firmness by 4% (skin) and 22% (flesh) and fruit skin colour by 1° (hue), and an upgraded visual ripeness score. The increases in yield were associated with greater number of fruits per tree (up to 42%) indicating the liquid seaweed extract improved fruit set and retention per tree. Regular soil application of the seaweed extract to young trees (cv. Hass) in pots increased the root fresh weight by 22%. Overall, the regular application of the seaweed extract to avocado trees was found to be practical and economically viable for improving fruit production and post-harvest quality in Australian orchards. [ABSTRACT FROM AUTHOR]

The fungus Colletotrichum gloeosporioides, which is the causal agent of anthracnose disease in green-skinned avocados, is responsible for significant postharvest fruit losses. In this context, strategies should be considered to avoid this problem. The use of essential oil (EO) can represent an alternative to contribute to antifungal activity, avoiding the use of chemical products, as their indiscriminate use can have harmful effects on human health. It is known that essential oil (EO) may exhibit antifungal activity and can be used as an alternative to chemical products. Therefore, the potential of using Lippia sidoides EO to control this fungus was investigated through in vitro evaluation (MIC and EC50) on C. gloeosporioides isolated from avocados. Furthermore, the potential of incorporating this oil with carboxymethylcellulose (CMC) for postharvest treatment in avocados was assessed in vivo to control anthracnose and maintain their physicochemical and sensory quality. The EO from L. sidoides demonstrated a MIC of 125 μl L−1 and an EC50 of 46.83 μl L−1 against this pathogen. The results indicated that the CMC edible coating associated with L. sidoides EO exhibited a positive effect on fruit quality during cold storage. In terms of sensory aspects, avocados treated with L. sidoides EO associated with CMC showed improved appearance compared to the control treatment. These findings suggest that L. sidoides EO has potential in the postharvest treatment of avocados. Additionally, these results are significant and unprecedented for this crop, as research on the postharvest effects of incorporating this EO with edible coatings in avocados is still limited. [ABSTRACT FROM AUTHOR]

Key message: Covering young 'Hass' trees with Silver 60% shading nets during cold winters mitigates frost damage and improves tree performance, apparently through a mechanism other than increasing nighttime air temperature. Avocado is a commercially important subtropical evergreen fruit tree. Severe frost may damage foliage, floral buds, flowers and fruit, thereby reducing avocado crop yield and restricting its geographical distribution and expansion. Shading nets are frequently used to protect agricultural crops from climate-related damage. To determine their ability to mitigate frost damage, Silver 60% shading nets were deployed over young 'Hass' trees during two consecutive winters and uncovered trees served as controls. Freezing and chilling temperatures occurred in the experimental orchard during the winter of each year, from December to March, reaching − 2.49 ℃ in January 2022. In the control, 93% of the examined floral buds were severely damaged compared to 4% in the Silver 60% trees. Damage to young vegetative shoots was assessed at 4.35 out of 5 in the control compared to 0.5 out of 5 in the Silver 60% trees. In both years, minimum air temperatures under the Silver 60% shading nets were similar to those of the control. Leaf-level photosynthetic photon flux density was ~ 60% lower under the shading nets. In most measurements, CO2-assimilation rate, stomatal conductance, ratio of variable to maximum fluorescence (Fv/Fm) and chlorophyll concentration in the leaves of the Silver 60% trees were higher than, or similar to the controls. Trunk diameter and flowering intensity of the Silver 60% trees were higher than for the control. These results indicate that covering young 'Hass' trees with Silver 60% shading nets during cold winters can mitigate frost damage and improve tree performance. [ABSTRACT FROM AUTHOR]

Colorectal cancer is a widespread neoplasia with high ratios of chemoresistance. Phytochemicals in plant-based extracts could be useful to treat colorectal cancer, and/or reduce chemoresistance. Methanolic extract of avocado mesocarp (MEAM) has demonstrated antitumoral properties, depending on the fruit ripening stage (RS). The aim of this study was to analyze the effects of methanolic extracts of "Hass" avocado fruit at different RS on cytotoxicity, antioxidative, anti-inflammatory, anti-invasive, cell cycle, and epithelial–mesenchymal transition inhibition in colorectal adenocarcinoma cell line HT29. The MEAM showed an increasing concentration of total phenolic compounds as the RS progressed, which was correlated with antioxidant capacity measured by the Ferric Reducing Antioxidant Power assay but not with the 2.2-diphenyl-1-picrylhydrazyl assay. The specific phenolic compounds of MEAM were determined by high-performance liquid chromatography, and it was found that concentrations of epicatechin decreased while concentrations of chlorogenic acid increased as the RS progressed. The HT29 cell line was treated with MEAM for 48 h, and all MEAM had a cytotoxic effect, reported by MTT assay, nevertheless, the strongest effect was associated with the presence of chlorogenic acid. MEAM induced apoptosis and cell cycle arrest in phase G0/G1, reported by flow cytometry. Moreover, MEAM inhibited cell migration evidenced by the wound healing assay. On the other hand, MEAM significantly reduced expression of mRNA of tumor necrosis factor-alpha and cyclooxygenase 2. These effects comprise important inhibition of some hallmarks of cancer. This, in turn, may provide interesting guidelines for developing antitumoral intervention agents. [ABSTRACT FROM AUTHOR]

Avocado paste (AP) is the main industrial byproduct of its processing, and retains various phenolic compounds (PCs). PCs are known to normalize the plasma lipid profile, but those from avocado byproducts have been minimally studied. We report the normalizing effects of an AP-derived phenolic extract (PE) on the plasma lipid profile of male Wistar rats. A standard (SD) and high-fat diet (HFD) were formulated, and the same diets were supplemented with 1 g/kg of diet of PE (SD + PE and HFD + PE). Rats were fed these diets during an 8-week period. The HFD induced signs of dyslipidemia, but PE treatment countered the decrease in HDL. Relative mRNA expression (real-time PCR) of the hepatic HDL receptor (SCARB1) increased in both groups (SD + PE and HFD + PE), while the LDR receptor (LDLR) increased in SD + PE group. The mRNA expression of apolipoproteins APOA1 and APOB was unaffected. We conclude that PCs from AP can counter a diet-induced decrease in plasma HDL by acting on the mRNA expression of its hepatic receptor. [ABSTRACT FROM AUTHOR]

Grafting, the careful selection of rootstocks and scions, has played a crucial role maintaining Chilean avocado fruit quality standards in a scenario in which climate change and drought-related issues have considerably decreased avocado fruit production in the last fifteen years. The historical use of seedling rootstocks in Chile has experienced a recent shift towards clonal rootstocks, driven by the potential to produce more consistent and predictable crops. This research aims to compare Hass avocado plants grafted on Mexicola seedling and Dusa® clonal rootstocks in a soilless and protected system using (i) a differential expression analysis of root and leaf samples and (ii) a fruit transcriptomic and metabolomic integration analysis to improve our understanding of rootstock–scion interaction and its impact on avocado tree performance and fruit quality. The results demonstrated that no significant transcriptomic and metabolomic differences were identified at fruit level in the ready-to-eat (RTE) stage for Hass avocado fruit from both rootstocks. However, Hass avocados grafted on the clonal rootstock showed greater aerial growth and slightly increased fruit size than the seedling rootstock due to the enrichment of cell wall-remodeling genes as revealed in leaves and fruit at harvest stage. [ABSTRACT FROM AUTHOR]

Copyright of Cameroon Academy of Sciences Journal is the property of Cameroon Academy of Sciences 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.)

Driven by its healthy and nutritious attributes, the US avocado market has experienced tremendous growth over the past two decades. This publication provides a comprehensive overview of US avocado production and trade. The US avocado market, marked by the decline of already limited US domestic production, is increasingly reliant on imports, especially those from Mexico. This overview aims to inform industry stakeholders and policymakers of the current state of the industry and offer insights into its sustainability.

Le but du présent travail a été d’identifier les plantes médicinales utilisées par les parents des sujets drépanocytaires pour la prise en charge de la maladie et d’évaluer l'activité anti-drépanocytaire et anti-inflammatoire des plantes les plus citées (Ipomoea batatas et Persea americana). Une enquête par la technique d’échantillonnage en boule de neige a été réalisée auprès 30 parents (25 à 89 ans d’âge). L’enquête ethno-botanique a permis de répertorier 30 espèces distribuées dans 30 genres et 25 familles botaniques. Les familles les plus représentées étaient les Fabaceae, les Acanthaceae et les Buseraceae. La florule recensée est constitué de cinq formes de vie principales notamment les arbres, les arbustes, les sous-arbustes les lianes et les herbes vivaces. Les arbres (10 espèces) et les arbustes (9 espèces) étaient dominants suivis respectivement des herbes vivaces (7 espèces); des lianes (3 espèces) et les sous-arbustes (1 espèce). Les analyses phyto-chimiques ont révélé que les feuilles de Ipomoea batatas contiennent de saponines, de polyphénols, de anthocyanes, de flavonoïdes, de quinones liées, de leucoanthocyanes, de tanins, de alcaloïdes et de stéroïdes. Par contre, les feuilles de Persea americana contiennent de saponines, des anthocyanes, de flavonoïdes, de quinones liées, de leucoanthocyanes, de tanins et de stéroïdes. Les extraits bruts hydro-alcooliques de deux plantes ont montré une activité anti-falcémiante in vitro. A la dose de 89,3 µg/mL, ces extraits sont plus actifs que le Diclofénac sodique (39,7 %). En outre, l’extrait aqueux est plus actif que l’extrait organique. Persea americana (84,3% vs 78,0 %) est plus actif en milieu aqueux tandis que Ipomoea batatas (58,3 % vs 52,0 %) est plus actif en milieu organique. Les feuilles de I. batatas sont douées des propriétés anti-drépanocytaires in vitro. La concentration minimale de normalisation (CMN), c’est-à-dire la plus faible concentration pour laquelle le taux de normalisation est maximal, a été évaluée à 30 µg/mL. Mots clés: Drépanocytose, Inflammation, Médecine Traditionnelle, Ipomoea batatas, Persea americana

Different postharvest diseases and disorders affect ‘Hass’ avocado fruits. Among them, lenticel-like damages, which compromise the fruit epidermis without affecting the mesocarp, are important causes of fruit rejection worldwide. However, lenticel-like damage etiology is still unclear. To better comprehend this disorder, we evaluated the level of the lenticel-like damage from Hass avocado fruits from two different growing regions in Colombia at different harvest seasons. We also characterized the fungal microbial communities associated with these fruits by Illumina MiSeq. We found that the level of lenticel-like damage varies with the farm and with the harvest season, and increases during cold storage. Fungal communities associated with Hass avocado fruits were influenced by the farm and the lenticel-like damage level. Regardless of the farm, Ascomycetes were increased four-fold compared with Basidiomycetes in severely damaged fruits, while in mildly damaged fruits the ratio was equal. In particular, severely damaged fruits from the more affected farm (El Sinaí) were enriched in Colletotrichum and Pseudocercospora, while fungi in mildly damaged fruits from the less affected farm (La Escondida) include Cladosporium, Vishniacozyma, Meira, and Symmetrospora. Altogether, our results suggests that fungal communities of Hass avocado exocarps influence the lenticel-like damage development and might be responsible for the damage differences between farms.

The increasing incidence of heat stress due to global climate change poses a significant challenge to avocado (Persea americana) cultivation, particularly in regions with intense solar radiation. This review evaluates sun protection strategies, focusing on the efficacy of different sunscreen products such as kaolin, titanium dioxide, and calcium oxide in mitigating thermal stress in avocado trees. The application of these materials was shown to reduce leaf and fruit surface temperatures, improve photosynthetic efficiency, and enhance fruit quality by preventing sunburn and dehydration. Despite these benefits, challenges remain, including the optimal timing and dosage of application, and the potential residue impacts on fruit marketability. The review emphasizes the need for ongoing research to develop more effective formulations and to integrate these sun protection strategies with other agronomic practices. The role of extension services in educating producers about the proper use of these technologies is also highlighted as crucial for the successful adoption of sun protection measures in avocado farming.

The avocado crop is relevant for its economic importance and because of its unique evolutionary history. However, there is a lack of information regarding the molecular processes during the defense response against fungal pathogens. Therefore, using a genome-wide approach in this work, we investigated the transcriptional response of the Mexican horticultural race of avocado (Persea americana var. drymifolia), including miRNAs profile and their possible targets. For that, we established an avocado–Fusarium hydroponic pathosystem and studied the response for 21 days. To guarantee robustness in the analysis, first, we improved the avocado genome assembly available for this variety, resulting in 822.49 Mbp in length with 36,200 gene models. Then, using an RNA-seq approach, we identified 13,778 genes differentially expressed in response to the Fusarium infection. According to their expression profile across time, these genes can be clustered into six groups, each associated with specific biological processes. Regarding non-coding RNAs, 8 of the 57 mature miRNAs identified in the avocado genome are responsive to infection caused by Fusarium, and the analysis revealed a total of 569 target genes whose transcript could be post-transcriptionally regulated. This study represents the first research in avocados to comprehensively explore the role of miRNAs in orchestrating defense responses against Fusarium spp. Also, this work provides valuable data about the genes involved in the intricate response of the avocado during fungal infection.

Carbohydrate levels are important regulators of the growth and yield of tree crops. Current methods for measuring foliar carbohydrate concentrations are time consuming and laborious, but rapid imaging technologies have emerged with the potential to improve the effectiveness of tree nutrient management. Carbohydrate concentrations were predicted using hyperspectral imaging (400–1000 nm) of leaves of the evergreen tree crops, avocado, and macadamia. Models were developed using partial least squares regression (PLSR) and artificial neural network (ANN) algorithms to predict carbohydrate concentrations. PLSR models had R2 values of 0.51, 0.82, 0.86, and 0.85, and ANN models had R2 values of 0.83, 0.83, 0.78, and 0.86, in predicting starch, sucrose, glucose, and fructose concentrations, respectively, in avocado leaves. PLSR models had R2 values of 0.60, 0.64, 0.91, and 0.95, and ANN models had R2 values of 0.67, 0.82, 0.98, and 0.98, in predicting the same concentrations, respectively, in macadamia leaves. ANN only outperformed PLSR when predicting starch concentrations in avocado leaves and sucrose concentrations in macadamia leaves. Performance differences were possibly associated with nonlinear relationships between carbohydrate concentrations and reflectance values. This study demonstrates that PLSR and ANN models perform well in predicting carbohydrate concentrations in evergreen tree-crop leaves.

Optimal fruit production from many tree crops relies on the transfer of cross-pollen between trees of different cultivars rather than the transfer of self-pollen between trees of the same cultivar. However, many orchards are established with wide blocks of single cultivars, which can result in high percentages of self-fertilised fruit and sub-optimal yield and quality. We aimed to determine whether outcrossing rates and yield of Hass avocado fruit decline with increasing distance from polliniser trees of cultivar Shepard and whether selfed fruit are smaller than outcrossed fruit. Outcrossing rates declined from 49% at six trees (40 m) from a block of Shepard trees to 30% at thirty trees (160 m) from a block of Shepard trees. Tree yield across this distance declined by 44% as a result of a 69% decline in the number of outcrossed fruit per tree, without a significant decline in the number of selfed fruit per tree. Outcrossed Hass fruit were 12% heavier than selfed Hass fruit, with 3% greater diameter and 5% greater length. The study results demonstrate the importance of interplanting Type B avocado pollinisers closely with Type A Hass trees to increase fruit yield and size. [ABSTRACT FROM AUTHOR]

Objective / Background. The objective was to assess the biocontrol capacity of Bacillus sp. A8a in avocado (Persea americana) plants infected by Phytophthora cinnamomi. Materials and Methods. A greenhouse experiment was implemented with four treatments: 1) control plants; 2) plants infected with P. cinnamomi; 3) plants inoculated with Bacillus sp. A8a; 4) plants infected with P. cinnamomi and inoculated with Bacillus sp. A8a. We evaluated several morpho-physiological variables during the experiment, which lasted 25 days after infection (dai). Moreover, we analyzed tannin density in stems at 25 dai to determine the plant defense response against the disease. Results. Inoculation with strain A8a reduced wilting symptoms by 49 % at 25 dai, compared with non-inoculated plants. No differences were detected in morphophysiological variables between treatments. However, a greater tannin accumulation was registered in the xylem of infected plants, whilst plants inoculated with strain A8a displayed a larger tannin density in the cortex. Conclusion. Our results confirm the biocontrol activity of Bacillus sp. A8a in avocado plants and suggest that tannin differential accumulation in the cortex of plants inoculated with the bacteria may contribute to the enhanced tolerance of avocado plants against Phytophthora root rot. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciencia y Tecnología Agropecuaria is the property of Agrosavia 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.)

Copyright of Revista Chapingo Serie Horticultura is the property of Universidad Autonoma Chapingo 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.)

Following an EFSA commodity risk assessment of bonsai plants (Pinus parviflora grafted on Pinus thunbergii) imported from China, the EFSA Plant Health Panel performed a pest categorisation of Pestalotiopsis microspora, a clearly defined plant pathogenic fungus of the family Pestalotiopsidaceae. The pathogen was reported on a wide range of monocotyledonous, dicotyledonous and gymnosperms, either cultivated or wild plant species, causing various symptoms such as leaf spot, leaf blight, scabby canker, fruit spot, pre‐ and post‐harvest fruit rot and root rot. In addition, the fungus was reported as an endophyte on a wide range of asymptomatic plant species. This pest categorisation focuses on the hosts that are relevant for the EU and for which there is robust evidence that the pathogen was formally identified by a combination of morphology, pathogenicity and multilocus sequencing analyses. Pestalotiopsis microspora was reported in Africa, North, Central and South America, Asia and Oceania. In the EU, it was reported in the Netherlands. There is a key uncertainty on the geographical distribution of P. microspora worldwide and in the EU, because of the endophytic nature of the fungus, the lack of surveys, and because in the past, when molecular tools were not fully developed, the pathogen might have been misidentified as other Pestalotiopsis species or other members of the Pestalodiopsidaceae family based on morphology and pathogenicity tests. Pestalotiopsis microspora is not included in Commission Implementing Regulation (EU) 2019/2072. Plants for planting, fresh fruits, bark and wood of host plants as well as soil and other growing media associated with plant debris are the main pathways for the entry of the pathogen into the EU. Host availability and climate suitability in parts of the EU are favourable for the establishment and spread of the pathogen. The introduction and spread of the pathogen into the EU are expected to have an economic and environmental impact where susceptible hosts are grown. Phytosanitary measures are available to prevent the introduction and spread of the pathogen into the EU. Unless the restricted distribution in the EU is disproven, Pestalotiopsis microspora satisfies all the criteria that are within the remit of EFSA to assess for this species to be regarded as potential Union quarantine pest. [ABSTRACT FROM AUTHOR]

Persea americana Mill. (avocado fruit) has many health benefits when added to our diet due to various pharmacological activities, such as preventing bone loss and inflammation, modulating immune response and acting as an antioxidant. In the current study, the total ethanol extract (TEE) of the fruit was investigated for in vitro antioxidant and anti-inflammatory activity via DPPH and cyclooxygenase enzyme inhibition. Biological evaluation of the antiarthritic effect of the fruit extract was further investigated in vivo using Complete Freund's Adjuvant (CFA) arthritis model, where the average percentages of body weight change, inhibition of paw edema, basal paw diameter/weight and spleen index were estimated for all animal groups. Inflammatory mediators such as serum IL-6 and TNF-α were also determined, in addition to histopathological examination of the dissected limbs isolated from all experimental animals. Eighty-one metabolites belonging to different chemical classes were detected in the TEE of P. americana fruit via UPLC/HR-ESI–MS/MS. Two classes of lyso-glycerophospholipids; lyso-glycerophosphoethanolamines and lysoglycerophosphocholines were detected for the first time in avocado fruit in the positive mode. The TEE of fruit exhibited significant antioxidant and anti-inflammatory activity in vitro. In vivo anti-arthritic activity of the fruit TEE improved paw parameters, inflammatory mediators and spleen index. Histopathological findings showed marked improvements in the arthritic condition of the excised limbs. Therefore, avocado fruit could be proposed to be a powerful antioxidant and antiarthritic natural product. [ABSTRACT FROM AUTHOR]

This study was aimed at investigating the effect of ethanolic extract of Persea americana fruit peels on serum hepatic and renal indices in crude oil contaminated diet stimulated toxicity in male Wistar rats using appropriate standard methods. The findings of this study revealed that the treatment of rats exposed to contaminated diets with the varying doses of P. americana fruit peels extract had no statistically (p>0.05) significant effect on the AST, ALT and ALP compared to those exposed to only crude oil contaminated diet. However, there were observed significant decrease in ACP activities in crude oil extract treated group when compared to the crude oil control group. Conversely, glucose, total protein, albumin and globulin levels showed no significant difference across the crude oil extract treated group when compared to the crude oil control group. Also it was observed that there was a significant decrease (p<0.05) in levels of serum urea, potassium, calcium and chloride in the crude oil extract treated group when compared to the crude oil control group in a dose dependent manner. These activities potentiated by the ethanolic extract of P. americana fruit peels could be attributed to its medicinal properties. [ABSTRACT FROM AUTHOR]

The present study evaluated the performance of some enzymatic and non-enzymatic antioxidant systems against oxidative stress for 10 to 30 d of refrigeration (R) and 15 to 50 d in controlled atmosphere (CA) conditions in both exocarp and mesocarp of Hass avocados from early and late harvests and at shelf life (SL) or consumption maturity. The possible relationship of the antioxidant systems with the occurrence of physiological disorders is also evaluated. The results indicate that the enzymatic system—superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), phenylalanine ammonium lyase (PAL) and polyphenoloxidase (PPO)—as well as the non-enzymatic system—such as phenolic compounds (PC)—showed different responses to the stress generated during storage and shelf life. In general, SOD, CAT, PAL and PPO did not significantly vary in storage (R or CA). At consumption maturity, SOD, POD and PAL activities decreased in the mesocarp (RSL and CASL), while CAT increased in the exocarp for CASL15-50d. PC instead decreased in the exocarp as the harvest period progressed while it increased in the mesocarp. Physiological disorders (dark spots) showed only in refrigeration on the exocarp at R30d and in mesocarp at RSL30d coincident with low SOD and low SOD and POD activity values, as well as low PC contents (p-coumaric and its derivatives and caffeic acid derivatives), respectively. The results support the use of CA as a postharvest technology to prevent the development of physiological disorders through the joint action of antioxidative defenses during avocado transport to distant markets until consumption maturity is reached. [ABSTRACT FROM AUTHOR]

Hass avocado fruit diseases are one of the main marketing constraints in Colombia. To identify and reveal the diversity of fungi associated with diseases in fruits and peduncles, symptomatic samples were collected from 67 farms in the 9 main Hass avocado-producing municipalities of the department of Cauca located in southwestern Colombia. A total of 237 monosporic isolates were obtained that were subjected to DNA extraction, amplification of the ITS region, sequencing and functional diversity analysis based on Hill numbers by municipality and altitude. The results indicated that the genera Pseudocercospora, Diaporthe, Colletotrichum, Neofusiococcum, Lasiodiplodia and Pestatoliopsis were associated with fruit diseases. The genus with the highest number of effective species was Colletotrichum. The ITS region revealed 100% identity of the species Pseudocercospora norchiensis, which was the first report of this pathogen in the crop. There was a greater richness and diversity of associated species in the three municipalities, revealing that the higher the altitude was, the lower the richness and diversity of fungi associated with fruit diseases. These results will provide a better understanding of the identification and diversity of pathogenic microorganisms present in avocado production systems in this region of Colombia. [ABSTRACT FROM AUTHOR]

ABSTRACT Systematic analysis of scientific, industrial, and commercial information and the application of data science (DS) are alternatives to learn about trends and advances in value chains such as avocado. The objective of this study was to review current trends in research, technological development, and perception about the avocado subsector under tropical conditions using DS tools. A bibliometric analysis (BA) of scientific articles, technological developments, and patents in different sources of web information was implemented. Additionally, search algorithms and DS were designed to perform an analysis of trends from social media platforms in the avocado value chain. The BA identified patters associated with the avocado chain in Colombia, highlighting the increase in scientific-technical information, the grouping by work networks, the bias associated with departments and commercial varieties such as the high volume of works in Antioquia and cv. Hass, and the few high-value alternatives for the chain such as patents, industrial secrets, etc. Trends in social networks were linked to international markets, added value, and environmental aspects. Likewise, a disconnection was found between the needs of the avocado value chain and the existing offers. This study contributes as a competitive strategy for the local avocado subsector and generates a country-adjusted research agenda.

In this article, Persea americana aqueous peels extract was used to synthesize silver nanoparticles in a simple and environmentally friendly manner. The properties of synthesized silver nanoparticles (AV-AgNPs) were studied via several techniques, including UV–vis spectroscopy, DLS, TEM, EDX, and FTIR. The UV–Vis spectra analysis revealed that the highest absorption peak occurred at 428 nm, providing strong evidence for forming AV-AgNPs. The TEM results indicate that the synthesized AV-AgNPs were uniformly dispersed, exhibiting a spherical shape with an average size of 24 nm. EDX imaging also confirmed the presence of AgNPs. FTIR analysis shows P. americana's phenolic compounds and proteins significantly contribute to AV-AgNP synthesis and stabilization. In addition, the antimicrobial activity of AV-AgNPs was assessed against pathogenic bacteria commonly found in humans, exhibiting a moderate zone of inhibition against the selected pathogens. Additionally, AV-AgNPs were used in antioxidant studies with the robust antioxidant properties 2, 2 diphenyl-1-picrylhydrazyl (DPPH). In vitro studies have shown that AV-AgNPs can remarkably inhibit α-amylase in a dose-dependent manner, indicating their potential as antidiabetic agents. In silico research, it was revealed that naringenin derived from P. americana exhibited a strong binding to S. typhi and B. cereus (−8.7 and −7.5 kcal/mol, respectively). At the same time, quercetin demonstrated a high binding affinity and energy to α-Amylase (−8.9 kcal/mol). This study presents the first investigation into the biosynthesis of AgNPs utilizing the aqueous peel extract derived from P. americana with multiple uses, including antioxidant, antimicrobial, and antidiabetic activity.