Growth and Fruit morphometric characteristics of local avocado germplasm (Persea americana Mill.) grown in northern Tanzania.

Tanzania has a diverse agroecological area suitable for growing tropical fruits, including avocados. In Northern Tanzania, avocados have been growing under variable soil and altitudinal characteristics for over 100 years, allowing the naturalisation of this crop in this region. However, the region's avocado germplasm is uncharacterised, thus impeding the selection of elite genotypes for increased value and breeding programmes. This study examined the growth and fruit morphometric characteristics of avocado populations grown under variable soil pH and altitude in six districts in the Tanga, Kilimanjaro and Arusha regions. Variations in growth and fruit morphometric characteristics were compared using a one-way analysis of variance (ANOVA). Pearson product-moment correlations (r) were used to evaluate the relationship between studied growth and fruit morphometric traits. A linear mixed-effects model (LMM) was used to assess the influence of the soil pH, altitude, tree height, canopy diameter, and trunk diameter on fruit length, fruit diameter, pulp thickness, and seed diameter. Principal Component Analysis (PCA) was used to depict the extent of the racial admixtures in the avocado germplasm in the Northern regions of Tanzania. The results revealed a significant variation in growth and fruit morphometric characteristics (p < 0.05). The Korogwe population had the highest tree height, while the Karatu had the lowest. Tree height was positively correlated with the trunk diameter (r = 0.63, p < 0.001. There was a positive correlation between fruit length and pulp thickness (r = 0.51, p < 0.001), fruit diameter and pulp thickness (r = 0.47, p < 0.001), and fruit length and fruit diameter (r = 0.36, p < 0.001). The fruit diameter was positively correlated with the seed diameter (r = 0.61, p < 0.001). There was a significant but weak association between fruit length and trunk diameter (-0.01), fruit length and canopy diameter (0.15), and between seed diameter and tree height (2.95e-2). These findings highlight the influence of individual tree genetic makeup on the variation in growth and fruit morphometric characteristics. The morphometric trait correlations may prove valuable in field measurements, especially when resources are limited. The study further indicates the presence of all avocado races within the local germplasm, highlighting its high diversity. Remarkably, the observed admixture of variant races implies gene flow among studied avocado populations, possibly facilitated by sharing seedlings among farmers or seed disposal through avocado fruit trading. Further study is needed, particularly in quantifying the above-ground biomass of local avocados in northern Tanzania, potentially contributing to carbon credit initiatives for fruit crops..

Comparative transcriptional analysis of Persea americana MYB, WRKY and AP2/ERF transcription factors following Phytophthora cinnamomi infection.

Plant cells undergo extensive transcriptional reprogramming following pathogen infection, with these reprogramming patterns becoming more complex when pathogens, such as hemibiotrophs, exhibit different lifestyles. These transcriptional changes are often orchestrated by MYB, WRKY and AP2/ERF transcription factors (TFs), which modulate both growth and defence-related gene expression. Transcriptional analysis of defence-related genes in avocado (Persea americana) infected with Phytophthora cinnamomi indicated differential immune response activation when comparing a partially resistant and susceptible rootstock. This study identified 226 MYB, 82 WRKY, and 174 AP2/ERF TF-encoding genes in avocado, using a genome-wide approach. Phylogenetic analysis revealed substantial sequence conservation within TF groups underscoring their functional significance. RNA-sequencing analysis in a partially resistant and susceptible avocado rootstock infected with P. cinnamomi was indicative of an immune response switch occurring in either rootstock after 24 and 6 h post-inoculation, respectively. Different clusters of co-expressed TF genes were observed at these times, suggesting the activation of necrotroph-related immune responses at varying intervals between the two rootstocks. This study aids our understanding of avocado immune response activation following P. cinnamomi infection, and the role of the TFs therein, elucidating the transcriptional reprogramming disparities between partially resistant and susceptible rootstocks.

Identity, pathogenicity and genetic diversity of Lasiodiplodia associated with stem-end rot of avocado in China.

Stem-end rot (SER) causes brown necrotic lesions in the pulp near the base of the fruit pedicel and is one of the most devastating postharvest diseases of avocados in all avocado growing regions of the world. China's avocado industry is growing very rapidly, and the planting area is expanding, but little is known about the pathogens and genetic diversity of avocado SER. To determine the causal agents of SER, avocado fruits were sampled from the main avocado-producing areas in China during 2020 and 2021. Fungal isolates were obtained from SER symptomatic avocado fruits and identified by morphology combined with phylogenetic analysis of internal transcribed spacer (ITS), translation elongation factor 1-α (EF1-α) and ß-tubulin (TUB2) gene sequences. All 101 isolates belonged to Lasiodiplodia spp., and four Lasiodiplodia species were identified, namely L. pseudotheobromae (59.41%), L. theobromae (24.75%), L. mahajangana (7.92%), L. euphorbiaceicola (1.98%), and six others are classified as Lasiodiplodia sp. (5.94%). There were only slight morphological differences in colonies and conidia of these four species of Lasiodiplodia. The pathogenicity tests showed symptoms of SER, and the 92.08% of the isolates exhibited a high level of virulence on avocado (disease index > 70), related to the disease severity on avocado fruit. All tested isolates grew well under conditions from 23 to 33℃. There was a significant difference in mycelial growth between the four species of Lasiodiplodia after treatment with high temperature or low temperature. L. pseudotheobromae growth was the fastest at 13 to 18℃, but was the lowest at 38℃ (P < 0.05). Red pigment could be produced by all tested isolates after culturing for 7 days at 38℃. The mycelial growth rate was the fastest on PDA medium, and the slowest on OMA medium but promoted spore formation (P < 0.05). In addition, was determined the genetic diversity of Lasiodiplodia pathogenic species associated with SER collected from avocado, mango, guava and soursop fruits was determined. A total of 74 isolates were clustered into 4 main ISSR groups by unweighted pair-group method with arithmetic mean (UPGMA) analysis, and the classification of this group was related to the host. Extensive diversity was detected in the Lasiodiplodia populations. The diverse geographical origins and host species significantly influenced the population differentiation, and most of the genetic variation occurred within populations (P < 0.001). This is the first study to identify the major pathogens of avocado SER in China and to survey their occurrence, pathogenicity and include a comparative analysis of genetic diversity with Lasiodiplodia spp. causing SER on other fruit hosts. Collectively, the Lasiodiplodia species complex affecting avocado showed high pathogenicity and diversity, while L. pseudotheobromae was the most frequently isolated species in China. The results of this study provide insights into the aspects of epidemic of SER disease caused by Lasiodiplodia species, which will help in developing strategies for the management and control of stem end-rot in avocado.

Introduction and establishment of Euwallacea fornicatus (Coleoptera: Curculionidae: Scolytinae) in Brazil.

Euwallacea fornicatus is an invasive tree pest able to infest healthy plants and cause damage to many host plants. This beetle has become established in several countries where it was introduced. It has now become established in Brazil, and while the original introduction site remains uncertain, there is a possibility of multiple introductions. We report the first evidence for the establishment of E. fornicatus with molecular confirmation, as well as its distribution, and host plants in Brazil. Euwallacea fornicatus has spread to main commercial avocado groves, other monocultures, and native vegetation in the country, and its pest status puts it as a threat, mainly to Brazilian avocado producers.

The Quality Evaluation of Avocado Fruits (Persea americana Mill.) of Hass Produced in Different Localities on the Island of Tenerife, Spain.

The effect of the production area on the quality of Hass avocados grown on the island of Tenerife was studied. For this purpose, several physicochemical parameters, such as fruit weight, percentage of pulp, seed and skin, proximate composition, minerals, total phenolic compounds (TP), total flavonoid compounds (TF), α-tocopherol, antioxidant capacity, and fatty acid profile were analyzed. The location of the orchards significantly influenced avocado weight; pulp and seed percentage; and fat, fiber, ash, α-tocopherol, TP, phosphorus, potassium, calcium, iron, zinc, and oleic and palmitoleic acid contents. Buenavista (BU) avocados were the smallest (185 g) and presented the highest percentage of pulp (77.1%) and lowest percentage of fiber (5.43%). The highest levels of dry matter (33.8%) and fat (20.4%) were found in avocados harvested in Los Silos (SI) and Santiago del Teide (SA), respectively. Compared with those at the other locations, the avocados harvested in Güímar (GU) had high levels of α-tocopherol (52.2 µg g-1) and phenolic compounds (56.0 mg GAE 100 g-1). Avocados from Los Realejos (RE) had the highest percentage of oleic acid and the lowest percentage of palmitoleic acid. Numerous significant correlations were found between the variables studied, especially those between TP, TF, and antioxidant capacity (DPPH) and between fat percentage and dry matter.

Near-freezing temperature suppresses avocado (Persea americana Mill.) fruit softening and chilling injury by maintaining cell wall and reactive oxygen species metabolism during storage.

To enhance the postharvest quality of avocado (Persea americana Mill.) fruit, this study investigates alterations in cell wall metabolism and reactive oxygen species (ROS) metabolism during near-freezing temperature (NFT) storage, and explores their impact on fruit softening. The fruit was stored at 25 °C, 5 °C, 2 °C, and NFT, respectively. NFT storage retarded firmness loss and chilling injury in comparison with 25 °C, 5 °C, and 2 °C. NFT storage delayed the decrease of ionic-soluble pectin (ISP) and cellulose (CLL) contents by suppressing cell wall degradation enzyme activities. Correlation analysis showed that cell wall degradation enzyme activities were positively correlated to rates of ethylene release and respiration. Moreover, NFT storage maintained higher levels of DPPH and ABTS scavenging abilities, activities of superoxide dismutase, peroxidase, and catalase, as well as ascorbate-glutathione cycle (ascorbic acid, glutathione, glutathione disulfide, ascorbate peroxidase, cycle-related enzymes), thereby inhibited the increase of ROS content, malondialdehyde content, and cell membrane permeability. Fruit firmness and chilling injury were correlated with the contents of hydrogen (H2O2), superoxide anion (O2.-), ISP, and CLL. These results suggested that NFT could suppress fruit softening and chilling injury by inhibiting cell wall degradation through delaying respiration and ethylene production and suppressing ROS production via activation of antioxidant systems, thereby maintaining quality and prolonged storage life during avocado fruit storage.

Association between avocado consumption and diabetes in Mexican adults: Results from the 2012, 2016, and 2018 Mexican National Health and Nutrition Surveys.

BACKGROUND: Avocado contains numerous vitamins, minerals, and phytochemicals, which can contribute to reducing the risk of metabolic syndrome and diabetes. However, limited studies have examined the association between avocados and diabetes risk. OBJECTIVE: This study aimed to examine the association between avocado consumption and diabetes by sex in Mexican adults. DESIGN: This was a cross-sectional study. PARTICIPANTS: /setting: Participants included a subsample of adults (>=20 years old) from the 2012, 2016, and 2018 Mexican National Health and Nutrition Survey (ENSANUT). Avocado consumption was assessed using a seven-day, semi-quantitative food-frequency questionnaire, and participants were classified as avocado consumers (consuming any amount of avocado) or non-consumers. MAIN OUTCOME MEASURES: Participants were considered to have diabetes if they answered "yes" to "Has a doctor ever told that you have diabetes or high blood sugar?" STATISTICAL ANALYSES PERFORMED: This analysis assessed the association between avocado intake and diabetes using multivariate logistic models by sex and adjusted for relevant covariates. RESULTS: Of 28,239 ENSANUT 2012, 2016, and 2018 participants, 25,640 met the criteria (i.e., have diabetes outcome and plausible energy and avocado intakes) for this study. Over half of the participants were women, and approximately 45% were avocado consumers, with an average (standard error) avocado consumption of 34.7 (0.9) among men and 29.8 (0.8) grams/day among women. Avocado consumers had lower odds of diabetes in both unadjusted (OR: 0.762, 95% CI: 0.639-0.907) and adjusted (OR: 0.792, 95% CI: 0.632-0.993) models among women but not men (OR: 1.192, 95% CI: 0.907-1.566 and OR: 0.914, 95% CI: 0.675-1.239 for both unadjusted and adjusted models, respectively). CONCLUSIONS: Avocado consumption was associated with a lower risk of diabetes, which remained significant even when adjusted for relevant covariates. However, this finding was observed in only women, not men, underscoring the importance of personalized nutrition in diabetes care and prevention.

Characterization of emulgels formulated with phycocyanin and diutan gum as a novel approach for biocompatible delivery systems.

Phycocyanin (PC), a protein derived from algae, is non-toxic and biocompatible. Due to its environmental and sustainable properties, it has been studied as an alternative stabilizer for food emulsions. In this sense, the main objective of this work is to evaluate the effectiveness of PC and its use in combination with diutan gum (DG), a biological macromolecule, to prepare emulgels formulated with avocado oil. Z-potential measurements show that the optimum pH for working with PC is 2.5. Furthermore, the system exhibited a structured interface at this pH. The surface tension did not decrease further above 1.5 wt% PC. Interestingly, emulsions formulated with >1.5 wt% PC showed recoalescence immediately after preparation. Although 1.5 wt% had the smallest droplet size, this emulsion underwent creaming due to the low viscosity of the system. DG was used in combination with PC to increase viscosity and reduce creaming. As little as 0.1 wt% DG was sufficient to form an emulgel when incorporated into the previous emulsion, which exhibited pseudoplastic behaviour and viscoelastic properties with very low creaming rates. However, the use of PC in combination with DG resulted in a non-aggregated and stable emulgel with 1.5 wt% PC and 0.1 wt% DG.

Avocado-derived extracellular vesicles loaded with ginkgetin and berberine prevent inflammation and macrophage foam cell formation.

Atherosclerosis, a chronic inflammatory disease of aorta, remains the major cause of morbidity and mortality among cardiovascular disease patients. Macrophage foam cell formation and inflammation are critically involved in early stages of atherosclerosis, hence chemopreventive targeting of foam cell formation by nutraceuticals may be a promising approach to curbing the progression of atherosclerosis. However, many nutraceuticals including berberine and ginkgetin have low stability, tissue/cell penetration and bioavailability resulting in inadequate chemotherapeutic effects of these nutraceuticals. We have used avocado-derived extracellular vesicles (EV) isolated from avocado (EVAvo ) as a novel carrier of nutraceuticals, in a strategy to alleviate the build-up of macrophage foam cells and expression of inflammatory genes. Our key findings are: (i) Avocado is a natural source of plant-derived EVs as shown by the results from transmission electron microscopy, dynamic light scattering and NanoBrook Omni analysis and atomic force microscopy; (ii) EVAvo are taken up by macrophages, a critical cell type in atherosclerosis; (iii) EVAvo can be loaded with high amounts of ginkgetin and berberine; (iv) ginkgetin plus berberine-loaded EVAvo (EVAvo(B+G) ) suppress activation of NFκB and NLRP3, and inhibit expression of pro-inflammatory and atherogenic genes, specifically Cd36, Tnfα, Il1ß and Il6; (v) EVAvo(B+G) attenuate oxidized low-density lipoprotein (oxLDL)-induced macrophage foam cell formation and (vi) EVAvo(B+G) inhibit oxLDL uptake but not its cell surface binding during foam cell formation. Overall, our results suggest that using EVAvo as a natural carrier of nutraceuticals may improve strategies to curb the progression of atherosclerosis by limiting inflammation and pro-atherogenic responses.

Pest categorisation of Pyrrhoderma noxium.

Following the commodity risk assessment of bonsai plants (Pinus parviflora grafted on Pinus thunbergii) from China performed by EFSA, the EFSA Plant Health Panel performed a pest categorisation of Pyrrhoderma noxium, a clearly defined plant pathogenic basidiomycete fungus of the order Hymenochaetales and the family Hymenochaetaceae. The pathogen is considered as opportunistic and has been reported on a wide range of hosts, mainly broad-leaved and coniferous woody plants, causing root rots. In addition, the fungus was reported to live saprophytically on woody substrates and was isolated as an endophyte from a few plant species. This pest categorisation focuses on the hosts that are relevant for the EU (e.g. Citrus, Ficus, Pinus, Prunus, Pyrus, Quercus and Vitis vinifera). Pyrrhoderma noxium is present in Africa, Central and South America, Asia and Oceania. It has not been reported in the EU. Pyrrhoderma noxium is not included in Commission Implementing Regulation (EU) 2019/2072. Plants for planting (excluding seeds), 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 factors occurring 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 in parts of the territory where hosts are present. Phytosanitary measures are available to prevent the introduction and spread of the pathogen into the EU. Pyrrhoderma noxium satisfies all the criteria that are within the remit of EFSA to assess for this species to be regarded as potential Union quarantine pest.

Avocado seed starch utilized in eco-friendly, UV-blocking, and high-barrier polylactic acid (PLA) biocomposites for active food packaging applications.

Efficient and effective use of biopolymers, such as starch, has increasingly prompted interest due to the current environmental challenges. However, starch-based composites still show poor ductility along with water and oxygen permeability, which may not meet the requirements for food packaging standards. In this study, modified starch (m-St), isolated from the avocado seed and synthesized with tert-butyl acetoacetate (t-BAA), was embedded into polylactic acid (PLA) to design new eco-friendly composites. The developed biocomposites were found to exhibit high performance with outstanding mechanical properties in conjunction with remarkable light, water vapor, and oxygen blocking features for food packaging applications. PLA/m-St(1:6) 20 wt% composites showed a dramatic increase in elongation at break (EB%) from 3.35 to 27.80 % (about 730 % enhancement) and exhibited remarkable UV-blocking performance from 16.21 to 83.86 % for UVB, relative to pure PLA. Equally importantly, these biocomposites revealed significant improvement in oxygen and water vapor barrier performance by reducing their values from 1331 to 32.9 cc m-2 day-1 (indicating a remarkable reduction of 97.53 %) and 61.9 to 28 g m-2 day-1, respectively. This study can show the great potential of extracting starch from biowaste resources and transforming it into sustainable bio-based composites as a promising solution for food packaging applications.

Co-Processed Crystalline Solids of Ivermectin with Span® 60 as Solubility Enhancers of Ivermectin in Natural Oils.

Despite being discovered over five decades ago, little is still known about ivermectin. Ivermectin has several physico-chemical properties that can result in it having poor bioavailability. In this study, polymorphic and co-crystal screening was used to see if such solid-state modifications can improve the oil solubility of ivermectin. Span® 60, a lipophilic non-ionic surfactant, was chosen as co-former. The rationale behind attempting to improve oil solubility was to use ivermectin in future topical and transdermal preparations to treat a range of skin conditions like scabies and head lice. Physical mixtures were also prepared in the same molar ratios as the co-crystal candidates, to serve as controls. Solid-state characterization was performed using X-ray powder diffraction (XRPD), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The FTIR spectra of the co-crystal candidates showed the presence of Span® 60's alkyl chain peaks, which were absent in the spectra of the physical mixtures. Due to the absence of single-crystal X-ray data, co-crystal formation could not be confirmed, and therefore these co-crystal candidates were referred to as co-processed crystalline solids. Following characterization, the solid-state forms, physical mixtures and ivermectin raw material were dissolved in natural penetration enhancers, i.e., avocado oil (AVO) and evening primrose oil (EPO). The co-processed solids showed increased oil solubility by up to 169% compared to ivermectin raw material. The results suggest that co-processing of ivermectin with Span® 60 can be used to increase its oil solubility and can be useful in the development of oil-based drug formulations.

Preventing microbe colonization on avocado (Persea nubigena var. guatemalensis) through metabiotic treatment, a promising postharvest safety improvement.

Introduction: Lactic acid bacteria (LAB) produce various metabolites (i.e. metabiotics) with inhibitory capacity towards harmful foodborne pathogens. Methods: This study aimed to design several antimicrobial formulations based on metabiotics obtained from different native LAB species (Lactobacillus pentosus UTNGt5, Lactococcus lactis UTNGt28, and Weissella cibaria UTNGt21O) and to detect the possible mode of action towards two multidrug resistant Staphylococcus spp. strains isolated from avocado (Persea nubigena var. guatemalensis) fruits. Additionally, the formulation with the highest inhibitory activity was tested ex vitro on avocados at the immature (firm) ripeness stage to evaluate their effect on microorganisms' growth and fruit quality attributes post-harvest. Results and discussion: Out of the top five formulations showing the highest bactericidal effect in vitro at their minimum inhibitory concentration (1 x MIC) on both Staphylococcus spp. targets one candidate annotated P11 (consisting of UTNGt21O and UTNGt28; 1:3, v/v) was selected. Co-cultivation of Staphylococcus strains with P11 formulation results in cell viability reduction by 98%, by impairing the integrity of the cell membrane inducing cytoplasm molecule content leakage, protein profile changes, and finally bacterial death. Even though the total coliforms, Staphylococcus spp., Enterobacter spp., molds, and yeasts counts were not fully eliminated by day 13 of storage, a statistically significant reduction (p < 0.05) in viable cell counts were observed by day 8 upon the P11 treatment compared with non-treated control (C) and treated with a commercial disinfectant (T1) samples, suggesting that P11 formulation inhibited microbial colonization during storage. Likewise, no visible dark spots were observed on the mesocarp (pulp) upon the treatment with P11, whereas T1 and C fruits showed greater dark spots on the pulp as indicative of damage. The quality attributes, such as pH, total soluble solids, total titratable acidity, antioxidant capacity, and total polyphenol content, were not affected by the treatment. Principal Component Analysis (PCA) conducted on these five variables showed a clear separation of samples according to the maturity stage regardless of the treatment. Conclusion: These results suggest that the active metabolites from LAB strains might create a barrier between the exocarp and mesocarp, inhibiting the microorganisms colonization, reducing fruit damage, and lengthening the fruit quality and safety after harvest.

Activated carbon from avocado seed as sorbent phase for microextraction technologies: activation, characterization, and analytical performance.

According to green analytical chemistry principles, the use of agricultural byproducts as sorbent phases is an interesting topic due to their lignocellulosic origin, as they are biodegradable and inexpensive. To the best of our knowledge, this is the first study in which avocado seed and avocado seed activated carbon are proposed as sustainable sorbents for solid-phase microextraction technologies, which were used to assess the proof of concept. Rotating disk sorptive extraction (RDSE) was used as a model technology and ibuprofen (Ibu) and 1-hydroxy-ibuprofen (1-OH-Ibu) as representative analytes. It was found that activated carbon (AC) prepared at 600 °C with an impregnation ratio (raw material/activating agent (ZnCl2), w/w) of 1:1.2 had better extraction efficiency than other ACs obtained at different temperatures, impregnation ratios, and activating agents (K2CO3). Characterization revealed several differences between natural avocado seed, biochar prepared at 600 °C, and selected AC since the typical functional groups of the natural starting material begin to disappear with pyrolysis and increasing the surface area and pore volume, suggesting that the main interactions between analytes and the sorbent material are pore filling and π-π stacking. By using this AC as the sorbent phase, the optimal extraction conditions in RDSE were as follows: the use of 50 mg of sorbent in the disk, 30 mL of sample volume, pH 4, 90 min of extraction time at a rotation velocity of the disk of 2000 rpm, and methanol as the elution solvent. The extracts were analyzed via gas chromatography coupled to mass spectrometry (GC-MS). The method provided limits of detection of 0.23 and 0.07 µg L-1 and recoveries of 81% and 91% for Ibu and 1-OH-Ibu, respectively. When comparing the extraction efficiency of the selected activated carbon with those provided by Oasis® HLB and C18 in RDSE, nonsignificant differences were observed, indicating that avocado seed activated carbon is a suitable alternative to these commercial materials.

Biological control of avocado branch blight caused by Lasiodiplodia theobromae using Bacillus velezensis.

In recent years, avocado branch blight has gradually become one of the major diseases causing mortality of avocado trees, which seriously affects the economic development of avocado planting regions. In order to investigate the cause of the disease, the pathogens were isolated from the inter-root of avocado trees with onset of the disease and identified as Lasiodiplodia theobromae. At the same time, three Bacillus velezensis strains, YK194, YK201, and YK268, with better antagonistic effect and high stability against L. theobromae, were isolated from the rhizospheric soil of healthy avocado plants. The results of branch experiments and field trials showed that the avocado leaves as well as branches treated with strains YK194, YK201, and YK268 did not develop disease, and the incidence of avocado trees was significantly reduced. In the branch experiments, the biological control effect of strains YK194, YK201 and YK268 reached 62.07%, 52.70% and 72.45%, respectively. In the field experiments, it reached 63.85%, 63.43% and 73.86%, respectively, which indicated that these three strains all possessed good biological control effects on avocado branch blight. Further investigation on the mechanism of action of antagonistic strains revealed that B. velezensis YK268 could produce lipopeptides: surfactin, fengycin and iturin, which could significantly inhibit the spore germination of L. theobromae. Consequently, these three isolates have potential as biocontrol agents against L. theobromae.

Isohydric stomatal behaviour alters fruit vascular flows and minimizes fruit size reductions in drought-stressed 'Hass' avocado (Persea americana Mill.).

BACKGROUND AND AIMS: Plant water status is important for fruit development, as 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 relations of the 'Hass' avocado plant, and its fruit growth. METHODS: Well-watered and water-stressed 'Hass' avocado plants were compared. Over four weeks, water flows through the shoot and fruit pedicel were monitored using external sap flow gauges. Fruit diameter was monitored using linear transducers (LTs), and stomatal conductance (gs), photosynthesis (A) and leaf and stem water potential (Ñ°leaf and Ñ°stem) were measured to assess the plants' response to water supply. KEY RESULTS: Under well-watered conditions, the average water inflow to the shoot was 72 g d-1. Fruit water inflow was 2.72 g d-1, but there was water loss of 0.37 g d-1 caused by the outflow (loss back into the tree) through the vascular tissues, and 1.06 g d-1 from the fruit skin. Overall, fruit volume increased by 1.4 cm3 d-1. In contrast, water flow into fruit of water-stressed plants decreased to 1.88 g d-1, with the outflow increasing to 0.61 g d-1. As a result, increases in fruit volume were reduced to 0.4 cm3 d-1. Following re-watering, a substantial recovery in growth rate was observed. A, gs, and sap flow to shoots were also reduced during drought conditions. 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.

One Avocado per Day as Part of Usual Intake Improves Diet Quality: Exploratory Results from a Randomized Controlled Trial.

Background: Few clinical trials have evaluated diet quality change as a predictor of intervention effectiveness. Objectives: The aim of this study was to examine changes in the Healthy Eating Index (HEI)-2015 after a food-based intervention, and assess the associations between HEI-2015 change and intervention effects on cardiometabolic risk-related outcomes. Methods: The Habitual Diet and Avocado Trial was a 26-wk, multicenter, randomized, controlled parallel-arm study. Participants were 1008 individuals aged ≥25 y with abdominal obesity (females ≥ 35 inches; males ≥ 40 inches). The avocado-supplemented diet group was provided 1 avocado per day, and the habitual diet group maintained their usual diet. Change in diet quality was assessed using the HEI-2015 from a single 24-h recall conducted at 4 time points. Mixed models were used for analysis. Results: The avocado-supplemented diet group had a greater increase in the HEI-2015 (4.74 points; 95% CI: 2.93, 6.55) at 26 wk than the habitual diet group. Compared with the habitual diet group, the avocado-supplemented diet group had greater increases in the following HEI-2015 components from baseline: total vegetables (0.99 points; 95% CI: 0.77, 1.21), fatty acid ratio (2.25 points; 95% CI: 1.74, 2.77), sodium (1.03 points; 95% CI: 0.52, 1.55), refined grains (0.82 points; 95% CI: 0.32, 1.31), and added sugars (0.84 points; 95% CI: 0.49, 1.19). No differences in HEI-2015 improvements were observed by race, ethnicity, study site, body mass index, or age category. In the avocado-supplemented diet compared with the habitual diet group, the HEI-2015 increased in females (6.50 points; 95% CI: 4.39, 8.62) but not in males (0.02 points; 95% CI: -3.44, 3.48). Median HEI-2015 change was not associated with intervention-related changes in cardiometabolic disease risk factors. Conclusions: Intake of 1 avocado per day for 26 wk in adults with abdominal obesity increased adherence to the Dietary Guidelines for Americans. Changes in diet quality did not predict changes in risk factors for cardiometabolic disease.This trial was registered at clinicaltrials.gov as NCT03528031 (https://clinicaltrials.gov/study/NCT03528031).

Characterization of antifungal properties of avocado leaves and majagua flowers extracts and their potential application to control Alternaria alternata.

Plant extracts are used as an alternative to a wide range of foods against different types of fungal pathogens. In the present study, the extracts of avocado leaves (Persea americana) and majagua flowers (Talipariti elatum) were tested according to their antifungal activity against different fungi. The most promising extracts were those of majagua flowers that were applied lyophilized and in aqueous extract, being very effective against Alternaria alternata and reaching a 50 % in vitro reduction. Antifungal properties were also evaluated during infection of apples by A. alternata. A decrease in infection progression was confirmed with up to a 30 % reduction in disease incidence and a 20 % reduction in disease severity. Majagua extracts were also tested combined with edible pectin coatings, greatly increasing their effectiveness up 60 % reduction. Thus, extracts of majagua could provide a feasible alternative to control fungal pathogens during postharvest.

Comparative analysis of antioxidant and fatty acid composition in avocado (Persea americana Mill.) fruits: Exploring regional and commercial varieties.

On Madeira Island, Portugal, the avocado crop benefits from a Mediterranean climate, exhibiting exceptional phytochemical and biochemical properties. Aiming to evaluate the antioxidant quality and fatty acid composition with a commercial avocado, flours were obtained from five varieties (four regional and one commercial Hass) across different tissues (pulp and by-products) and cycles (years and on-tree maturation stages). Results showed that a regional variety with thin purple skin had the highest antioxidant qualities and lipid content, surpassing the other regional and commercial Hass varieties. Oleic acid prevailed in all samples, with regional avocados containing arachidonic acid which is an uncommon occurrence among higher plants. Variations in fatty acid content were influenced by the timing of harvest. These outcomes highlight the promising potential of avocados from Madeira Island.