Postharvest Stage Research Articles

Planting Materials, Shading Effects, and Non-Destructive Estimation of Compound Leaf Area in Konjac (Amorphophallus Muelleri)

Konjac glucomannan has been commercially produced and used as functional food, food additives, food supplements, pharmaceutical and cosmetic, and biomaterials. Despite intensive and advance research at postharvest stage, knowledge on cultivation of konjac plants has been limited. This research covered current issues associated with selecting agronomically the most suitable planting material, shading effects on shoot emergence and growth characteristics, and non-destructive area estimation of the compound leaf in the konjac plants. Planting materials used were 81 true seeds, 81 bulbils and 81 cormels. Results of this study indicated that bulbil was a suitable planting material based on its early shoot emergence and size of above ground organs. Shading at 50 and 70 % exhibited a better performance in time of emergence and growth characteristics than konjac plant fully exposed to sunlight, even though the differences were not statistically significant. Total leaf blade area (LA) of the irregular konjac compound leaf can be accurately (R2 = 0.9932) and consistently estimated using the 0-intercept linear model and the multiplication product of total midrib length and average width of all leaflets (TLM×AWL) is used as predictor. The recommended formula is LA = 0.6761(TLM×AWL).
 HIGHLIGHTS
 
 Shoot emergence in konjac plant was significantly earlier if the true seed was used rather than bulbil and cormel as planting materials
 Plant grown using cormel and bulbil exhibited larger shoot and corm compared to those grown using true seed
 Shading at 50 and 70 % increased length of the pseudo-stem, total number of leaflet, and other morphological characters
 Total midrib length of all leaflets and average of all leaflet width (TLM×AWL) could be used as predictors for accurate LA estimation
 
 GRAPHICAL ABSTRACT

Aflatoxin Contamination, Its Impact and Management Strategies: An Updated Review.

Aflatoxin, a type of mycotoxin, is mostly produced by Aspergillus flavus and Aspergillus parasiticus. It is responsible for the loss of billions of dollars to the world economy, by contaminating different crops such as cotton, groundnut, maize, and chilies, and causing immense effects on the health of humans and animals. More than eighteen different types of aflatoxins have been reported to date, and among them, aflatoxins B1, B2, G1, and G2 are the most prevalent and lethal. Early detection of fungal infection plays a key role in the control of aflatoxin contamination. Therefore, different methods, including culture, chromatographic techniques, and molecular assays, are used to determine aflatoxin contamination in crops and food products. Many countries have set a maximum limit of aflatoxin contamination (2–20 ppb) in their food and agriculture commodities for human or animal consumption, and the use of different methods to combat this menace is essential. Fungal infection mostly takes place during the pre- and post-harvest stage of crops, and most of the methods to control aflatoxin are employed for the latter phase. Studies have shown that if correct measures are adopted during the crop development phase, aflatoxin contamination can be reduced by a significant level. Currently, the use of bio-pesticides is the intervention employed in many countries, whereby atoxigenic strains competitively reduce the burden of toxigenic strains in the field, thereby helping to mitigate this problem. This updated review on aflatoxins sheds light on the sources of contamination, and the on occurrence, impact, detection techniques, and management strategies, with a special emphasis on bio-pesticides to control aflatoxins.

Analysis of Consumer Satisfaction Levels on the Value of Sagoku Products From Sago Meambo Food, Mata output, Kendari District.

This study aims to study the process of sago processing at the Meambo Food Sago Business in the Mata Village, Kendari District, Kendari City, to determine the product development process using the Quality Function Deployment (QFD) method on sago processing at the Meambo Food Sago Business in the Mata Village, Kendari District, Kendari City. ". Data was collected using questionnaire, interview, documentation and observation methods. The results showed that the process of processing sago products from sago Meambo food The processing of Sagoku Meambo Food products begins with the post-harvest stage of sago fruit carried out by sago farmers who have collaborated with Meambo Food Sago Enterprises, then the next stage is the processing of sago into flour carried out by labor. The sago processing process is by washing sago, soaking sago, roasting sago using an oven, sifting sago using a sieve to produce sago flour, then using sago flour to make sago products. The needs of consumers in a row include: having a halal label (8.93%), including an expiration date (8.87%), including information on the type of taste (8.18%), sweetness (7.93%), new topping/stuffing variants (7.75%) ), more toppings/filling (7.75%), easy to get chocolate products (7.39%), no bitter taste (7.33%), unchanged taste (7.28%), soft texture (7.28%) , Has information on nutritional value in one package (7.28%) and packaging color according to product (6.57%).

Molecular Biology, Composition and Physiological Functions of Cuticle Lipids in Fleshy Fruits.

Fleshy fruits represent a valuable resource of economic and nutritional relevance for humanity. The plant cuticle is the external lipid layer covering the nonwoody aerial organs of land plants, and it is the first contact between fruits and the environment. It has been hypothesized that the cuticle plays a role in the development, ripening, quality, resistance to pathogen attack and postharvest shelf life of fleshy fruits. The cuticle’s structure and composition change in response to the fruit’s developmental stage, fruit physiology and different postharvest treatments. This review summarizes current information on the physiology and molecular mechanism of cuticle biosynthesis and composition changes during the development, ripening and postharvest stages of fleshy fruits. A discussion and analysis of studies regarding the relationship between cuticle composition, water loss reduction and maintaining fleshy fruits’ postharvest quality are presented. An overview of the molecular mechanism of cuticle biosynthesis and efforts to elucidate it in fleshy fruits is included. Enhancing our knowledge about cuticle biosynthesis mechanisms and identifying specific transcripts, proteins and lipids related to quality traits in fleshy fruits could contribute to the design of biotechnological strategies to improve the quality and postharvest shelf life of these important fruit crops.

PERFORMANCE AND FARMERS PARTICIPATORY SELECTION OF COWPEA VARIETIES IN SOUTHERN ETHIOPIA

<p><strong>Background. </strong>Farmers’ participation in varietal selection process is important to collect the actual feedbacks on their performance in the field and hastens promotion and popularization of technologies. The study was conducted during 2016-2017 main cropping seasons in Gofa district of southern Ethiopia. <strong>Objective.</strong><em> </em>To assess and select superior cowpea variety (ies) that meet needs of farmers and preferences through farmers’ participation<em>. </em><strong>Methodology. </strong>Data on agronomic traits were collected on plant and plot basis whereas at maturity and post harvest stages, farmers were requested to evaluate each variety. Eight cowpea varieties were laid out in a randomized complete block design (RCBD) with three replicates on the Gofa research station and additional unreplicated block at three nominated farmers’ fields from each testing site. <strong>Results.</strong> Analysis of variance (ANOVA) showed the existence of significant differences (p<0.05) among the tested varieties for all the measured agronomic traits. Combined mean values showed that Brazil-3 (1.65 t ha<sup>-1</sup>), Brazil-2 (1.62 t ha<sup>-1</sup>), Kenketi (1.53 t ha<sup>-1</sup>), and bole (1.52 t ha<sup>-1</sup>) were high-yielding varieties with a yield advantage of 3.9 to 12.2 % more than the check variety white wonderer trailing. In case of farmers’ evaluation using direct matrix and pair-wise ranking methods showed that Kenketi, Brazil-3, Brazil-2, and Bole<em> </em>were the most preferred varieties. The rank correlation analysis between varieties’ ranked by farmers and the varieties’ grain yield rank was positive across the tested villages.<em> </em><strong>Implication</strong>.<em> </em>These results lead to identify the farmers’ screening criteria needs to be incorporated into new varieties being developed which will contribute considerably to increased acceptance of improved cowpea varieties among smallholder farmers across the growing areas of southern Ethiopia.<strong>Conclusion</strong>. The results of this study have confirmed the need for researchers to incorporate farmers’ preferred traits in cowpea improvement programmes. The study also identified cowpea varieties Brazil-3, Brazil-2, Kenketi and Bole as potential ones that can be recommended for further demonstration, popularization, and dissemination on farmers’ fields to improve cowpea productivity in southern Ethiopia.</p>

Evaluation of animal- and green manures co-application on soil micronutrients and yield of sesame (Sesamum indicum L.) in organic farm condition

This study was conducted to evaluate effects of organic fertilizers on micronutrients status of soil and yield of sesame. Research was performed in split-plot design based on a randomized complete block design with three replications. The experimental treatments included animal manure as main factor at three levels (0, 10, and 20 t ha−1) and application of green manures as sub factor at four levels (no green manure, Berseem clover, Fenugreek, and Vicia villosa). The results showed by application of animal manure, copper (Cu), zinc (Zn), manganese (Mn), and ferrous (Fe) contents in the treatment of 20 t ha−1 of animal manure were about 27, 22, 7.5, and 6% higher than the control treatment, respectively. The soil analysis showed in the post-harvesting stage of sesame 2.7% Cu and 29% Zn were stored in the soil. While the amounts of Fe 11% and Mn 71% in the soil were less than pre-planting of sesame. In general, fenugreek green manure application increased the amounts of micronutrients of soil more than the other green manures and animal manure individually. The highest total dry weight (10720.0 kg ha−1), grain yield (1929.4 kg ha−1) and oil yield (946.8 kg ha−1) were observed in the 20 t ha−1 of animal manure and Fenugreek of green manure treatments, which were about 44, 52 and 50% higher than the non-application of animal and green manures treatments, respectively. In general, the application of organic manures increased sesame yield by improving the physico-chemical properties and the amount of soil micronutrients.

Adhesion capacity and biofilm formation by Escherechia coli and Salmonella sp. on tomato (Solanum lycopersicum L.) during the postharvest stage

ISHS V International Conference on Postharvest and Quality Management of Horticultural Products of Interest for Tropical Regions Adhesion capacity and biofilm formation by Escherechia coli and Salmonella sp. on tomato (Solanum lycopersicum L.) during the postharvest stage

Lacto-fermented polypeptides integrated with edible coatings for mango (Mangifera indica L.) bio-preservation

Mango (Mangifera indica L.) is one of the most important tropical fruits due to its pleasant taste and high nutrient content including vitamins, minerals, and phytochemicals. Post-harvest fungal diseases, mainly anthracnose, stem-end rot, and aspergillus rot are among the major problems in mango provision throughout all the supply chain stages. Fungal diseases create large economic losses and present a health risk for consumers due to the production of mycotoxins (aflatoxin and patulin). In the last two decades, chemical methods for fungal control have been prevalent because of their low cost and simple practicing features. However, recent consumer trends and regulations have limited the use of chemicals in fruits at the post-harvest stage. Bio-preservation is a promising alternative technique applied to control the post-harvest fungi with high safety for the consumer and environment. Antifungal polypeptides are made by different living beings including bacteria, fungi, protozoa, plants, invertebrates, and vertebrates. Polypeptides including small peptides produced by lactic acid bacteria (LAB) have a higher potential to employ as food bio-preservatives due to their promising antifungal ability with generally recognized as safe (GRAS) status. Lacto-fermented polypeptides inhibit a broad range of fungal growth, and thus enhance the quality and extend the shelf life through reducing biotic stress, respiration, and ethylene biosynthesis of post-harvested fruits. Recently, polypeptides, mainly bioactive peptides, and bacteriocins received great attention for their potential bio-preservation activity against pathogenic fungi in fruits. Moreover, the development of edible coating enhanced the stability of the bioactive polypeptides and expanded their applications for fruit preservation. This article reviews the fungi associated with main mango diseases, major causal organisms, antifungal activity of LABs’ polypeptides on mango, and their antifungal performances to control the postharvest mango spoilage. Besides, this review highlights the potential applications of Lacto-fermented polypeptides-enriched edible coating to control the pathogenic fungi of mango.

Phytic acid and its reduction in pulse matrix: Structure–function relationship owing to bioavailability enhancement of micronutrients

AbstractThe bioavailability of minerals and proteins in the pulse is endured due to the presence of antinutrient phytic acid. Phytic acid is a proton donor that produces hydrogen ions (H+) and “phytate” anion, which readily forms salts with available minerals and protein. These phytate complexes are not bioavailable to humans and led to several public health problems like anemia, skeletal abnormalities, osteoporosis, malabsorption, and kwashiorkor syndrome due to Fe, Mn, Ca, Zn, and protein deficiency. Thus, it is a severe concern to the vegetarian population who strongly rely upon pulses to fulfill their daily nutrition requirements. Improving the bioavailability of micronutrients in the pulse matrix requires reduction of phytic acid. A phytic acid reduction strategy should ensure its efficient reduction leading to enhanced micronutrient bioavailability. This article provides a throughout view of the available phytic acid reduction technologies conducted at the postharvest stages of pulse processing. The mechanism of phytic acid reduction during conventional (soaking, cooking, and germination) and novel processing (irradiation, ultrasound, and high pressure) regarding its degradation and interaction with other components has been explored here, providing insight into structure–function relationships. Further, an in‐depth analysis of the combined treatments offering better phytic acid reductions has been explained in the light of structural alteration of phytic acid to its lower inositol phosphates. The summarized data on prospects and drawbacks of different phytic acid reduction strategies would provide background information to explore the futuristic possibilities for efficient phytic acid reduction and micronutrient fortification.Practical ApplicationsThe presence of phytic acid in the pulse matrix restricts the micronutrient absorption by complexing with micronutrients leading to their ineffectiveness. The bottom‐line population of the income pyramid, who are unable to intake micronutrients from other sources, suffers from several public health problems related to nutrient or combined nutrient deficiencies. Therefore, the degradation of phytic acid in pulses is necessary. This article aims to provide a comprehensive overview and explanation of phytic acid degradation during various postharvest pulses processing. The chelation of micronutrients by phytate, structural alterations during processing, and structure–function correlation of pulse matrices have been comprehensively enlightened here. These insights will aid researchers in exploring the future potential for phytic acid reduction and help develop proper strategies for pulse fortification.

Postharvest quality maintenance of wax apple and guava fruits by use of a fermented broth of an ε-poly-l-lysine-producing Streptomyces strain.

ε-Poly-l-lysine (ε-PL) is a natural antimicrobial polymer with significant inhibitory activity against a broad spectrum of microorganisms, and nowadays used widely as a preservative in the food industry. In the present study, ε-PL broth was obtained from Streptomyces ahygroscopicus GIM8 fermentation in a nutrient-limited liquid medium. The in vitro antifungal activity of the broth against fruit pathogens Penicillium expansum and Colletotrichum gloeosporioides was investigated, and its usage for postharvest storage of two highly perishable fruits wax apple and guava was evaluated. Results showed that ε-PL concentration in the broth reached 0.61 g/L, and the nutrition level of the broth was low. The antifungal activity of ε-PL broth was comparable to that of the aqueous solution of ε-PL under the same concentration. Immersion with the diluted broth (200 mg/L ε-PL) markedly delayed the decline in the quality of postharvest wax apple and guava fruits during storage, and the decay incidences were also greatly decreased as compared to their respective controls (distilled water immersion). A further investigation demonstrated that the ε-PL broth immersion induced an increase in the activity of defense-related enzymes peroxidase and polyphenol oxidase in the two fruits during storage. The present study proved that the fermentation broth of ε-PL could be used as a promising alternative to high purity ε-PL and synthetic fungicides for preserving fruits at postharvest stage.

More sustainable vegetable oil: Balancing productivity with carbon storage opportunities

Intensive cultivation and post-harvest vegetable oil production stages are major sources of greenhouse gas (GHG) emissions. Variation between production systems and reporting disparity have resulted in discordance in previous emissions estimates. The aim of this study was to assess global systems-wide variation in GHG emissions resulting from palm, soybean, rapeseed and sunflower oil production. Such an analysis is critical to understand the implications of meeting increasing edible oil demand. To achieve this, we performed a unified re-analysis of life cycle input data from diverse palm, soybean, rapeseed, and sunflower oil production systems, from a saturating search of published literature. The resulting dataset reflects almost 6000 producers in 38 countries, and is representative of over 71% of global vegetable oil production. Across all oil crop systems, median GHG emissions were 3.81 kg CO2e per kg refined oil. Crop specific median emissions ranged from 2.49 kg CO2e for rapeseed oil to 4.25 kg CO2e for soybean oil per kg refined oil. Determination of the carbon cost of agricultural land occupation revealed that carbon storage potential in native compared to agricultural land cover drives variation in production GHG emissions, and indicates that expansion of production in low carbon storage potential land, whilst reforesting areas of high carbon storage potential, could reduce net GHG emissions whilst boosting productivity. Nevertheless, there remains considerable scope to improve sustainability within current production systems, including through increasing yields whilst limiting application of inputs with high carbon footprints, and in the case of palm oil through more widespread adoption of methane capture technologies in processing stages.

ShrimpChain: A blockchain-based transparent and traceable framework to enhance the export potentiality of Bangladeshi shrimp

Despite substantial progress achieved with shrimp production during the last three and a half decades, growth of shrimp export remains minimal in Bangladesh. In the absence of effective traceability and transparency practices, a wide range of malpractice occurs both at the production and post-harvest stages. Traditional paper-based record-keeping methods for the shrimp supply chain are disparate and, therefore, cannot provide efficient traceability capacity and holistic view of the supply chain. These limit the identification of any issues in earlier juncture to proactively ensure food safety, best practice, and good governance. Addressing this multiplexed challenge, we present here ShrimpChain, a public-private hybrid blockchain-based conceptual framework. Focusing on the export market and utilizing existing technologies, the conceptual framework addresses the traceability, transparency, and certification challenges associated with shrimp export. In this framework, from the post-larva purchasing to the final packaging stage, relevant data for every stage will be entered by the associated actors via mobile/web app or Internet of Things devices to the blockchain network. Data authentication will be achieved by a novel approach of incorporating community consensus in conjunction with the machine-derived data entry timestamping method. Instead of the traditional central and endpoint certification approach, we propose a distributed and accumulative score-based certification approach that will grade packaged shrimps according to the completeness and accuracy of the authenticated data entered during different stages. Such distributed approach of certification will enhance not only food safety but also the quality and compliance to best practices. Most importantly, engaging shrimp farmers in the safety and quality assurance as well as to the certification process will empower them to have better control over the market and incentive to produce high-quality shrimp for high-value market.

A New Calcium Vectoring Technology: Concentration and Distribution of Ca and Agronomic Efficiency in Pepper Plants

Calcium (Ca) is an important macronutrient for plants, although its low mobility through the phloem makes more difficult the translocation to growing tissues, including fruits. The blossom end rot (BER) physiopathy occurs mainly in fruits and is associated with water stress, and especially with low Ca levels, which has a very negative effect on the production of many crops. Currently, through the vectoring process, it is possible to increase the transport of immobile elements to the fruits. The objective of this study is to evaluate the effect of BRANDT® MANNI-PLEX® Ca, which contains Ca with a vector (polyalcohols), provided by the company BRANDT EUROPE S.L. (Carmona, Spain), on Ca accumulation and the production and quality of pepper fruits, both at harvest and post-harvest stage. Pepper plants were grown in a shaded greenhouse and supplied with BRANDT® MANNI-PLEX® Ca and parameters related to biomass, production, and fruit quality were analyzed. The results showed that the product increased shoot biomass, photosynthesis performance, Ca accumulation and quality of pepper fruits both at harvest and post-harvest, while reducing the incidence of Ca physiopathies by 70%. Therefore, this study proves the BRANDT® MANNI-PLEX® Ca efficacy in a crop with a high incidence of Ca physiopathies, such as pepper.

Analysis of post-harvest losses of banana and the economic wellbeing of farmers in Boyo Division, North West Region of Cameroon

Post-harvest losses of banana affect the economic wellbeing of farmers in Africa especially in Boyo Division in the North West region of Cameroon where majority of the producers are smallholders’ farmers. The study analysed post-harvest losses of banana and its effect on the economic wellbeing of farmers in Boyo Division. Three hundred and eighty respondents were selected from three out of four sub-divisions in Boyo Division using a multi-stage sampling procedure. Data was obtained from the respondents with the aid of questionnaire and focus group discussions. The data obtained was analysed using descriptive statistics. The results revealed that 61,055 bunches of banana were harvested, 21,107 bunches sold, 16,751 bunches used by farmers’ households while 23,197 bunches were lost at post-harvest stages in 2019/2020. This quantity lost was suffered at the farm level, transportation, storage, ripening, processing and sale stages with most losses (11-20) suffered at the farm level. The study further revealed that farmers expected an estimated net amount of 10,570,036 FCFA while an estimated net amount of 2,213,759 FCFA was achieved with post-harvest losses. The study therefore, concludes that post–harvest losses of banana have a positive correlation on farmers’ economic wellbeing and recommends sensitization and training of farmers on post-harvest management techniques.

Estimation of nutritional postharvest losses along food value chains: A case study of three key food security commodities in sub-Saharan Africa

Postharvest losses (PHLs) amplify food insecurity and reduce the amount of nutrients available to vulnerable populations, especially in the world's Low and Middle Income Countries (LMICs). However, little is known about nutrient loss at the various postharvest stages. The objective of our study was to develop a methodology and a tool to estimate nutritional postharvest losses (NPHLs) along food value chains for three distinct food commodities in sub-Saharan Africa. The study used a combination of literature, laboratory and field data to investigate NPHLs caused by both changes in quantity and quality of food material (quantitative and qualitative NPHLs, respectively). The method can be expanded to various other food value chains. A user-friendly predictive tool was developed for case studies involving maize and cowpea in Zimbabwe, and for sweet potato in Uganda. Quantitative and qualitative NPHLs were combined and converted into predicted nutrient loss and nutritional requirement lost due to postharvest losses. The number of people who may not meet their daily nutritional needs, as a result of the food and nutrient losses at country level, was estimated. The estimates consider nutritionally vulnerable groups such as children under five years and pregnant women. The nutrient density of the harvested food material, the level of food production, the postharvest stages along the food value chain, the levels of pest damage along the value chain, and the susceptibility of the nutrients to degradation e.g. during storage, are all important factors that affect NPHLs. Our modelling work suggests that reducing PHLs along food value chains could significantly improve access to nutritious food for populations in LMICs.

Chitosan molecular weights affect anthracnose incidence and elicitation of defence-related enzymes in avocado (Persea americana) cultivar ‘Fuerte’

Anthracnose decay is one of the major causes of postharvest losses of avocados (Persea americana), during marketing. Currently, Prochloraz® fungicide is used to control anthracnose at postharvest stage which poses threat to consumer safety. Therefore, this study evaluated the effects of high and low molecular weight chitosan on the control of avocado anthracnose and fruit defence mechanism. In curative inoculation, avocados ‘(Fuerte’) were inoculated via the wounds with C. gloeosporioides spore suspension (20 μL, 1 × 106 spores mL−1). Thereafter coated with different concentrations (0.5%, 1% and 1.5%) of low (LMWC) and high molecular weight (HMWC) chitosan and fruits were held at 25 °C for 5 days. The % anthracnose incidence in avocado fruits was recorded on day 5. During preventative inoculation, wounded fruits were dipped in different concentrations of LMWC or HMWC solutions, and subsequently inoculated with C. gloeosporioides suspension. Preventatively inoculated fruits were stored for 28 days at 6.5 °C, 85% RH and thereafter for 5 days at 25 °C and 75% RH to simulated market shelf condition. The % anthracnose incidence was recorded on day 5. Fruit treated with Prochloraz® and water were included as controls for both curative and preventative infected fruits. Promising chitosan coatings with the lowest anthracnose incidence and the controls were investigated for skin epicatechin content, defence-related genes; phenylalanine ammonia lyase (PAL), lipoxygenase (LOX), fatty acid elongase (avael) and desaturase (avfad 12–3), chalcone synthase (CHS) and flavonol synthase (FLS) using RT- qPCR method. The zeta potential of selected chitosan coatings was done following standard procedures. Percentage of anthracnose incidence were lowest in 1.5% LMWC (18%, 3 mm) compared to Prochloraz® (23%, 5 mm) and the untreated fruit (90%, 24 mm). The 1.5% LMWC had the highest up-regulation of PAL, avfael, avfad 12–3, CHS, FLS genes and down-regulation of LOX gene with concomitant increase in epicatechin content (340 mg kg−1) relative to other chitosan treatments, untreated and Prochloraz® treated fruits. The superior positive zeta potential of LMWC 1.5% coating corroborates its effectiveness in controlling avocado anthracnose than HMWC 1.5%. It is possible that the interaction between the positively charged chitosan amino group (-NH3+) and the negatively charged microbial cell membrane is responsible for the enhanced antifungal activity. In late season naturally infected fruits dipped in 1.5% LMWC, anthracnose incidence dropped to 28% while Prochloraz® treated fruits showed anthracnose incidence of 82% on day 8 at the market shelf. LMWC 1.5% can replace the currently used Prochloraz®.

Phylogenetic Diversity and Phenotypic Characterization of Phlyctema vagabunda (syn. Neofabraea alba) and Neofabraea kienholzii Causing Postharvest Bull's Eye Rot of Apple in Northern Italy.

Bull's eye rot, caused by Phlyctema vagabunda and Neofabraea species, is one of the most important postharvest diseases of apple. South Tyrol (northern Italy) is the largest continuous apple-producing area in Europe, with approximately 1 million tons being produced yearly and conserved in technologically advanced storage facilities for several months. Still, studies on the pathogen species causing postharvest bull's eye rot of apple, as well as their diversity and biology, are lacking for this region. Therefore, the main purpose of the present work was to identify and characterize fungal isolates obtained from decayed apple fruit with symptoms of bull's eye rot that were collected in 2018 and 2019 in different packinghouses in South Tyrol. Among more than 1,000 fungal isolates that were obtained, 419 could be assigned to the genera Phlyctema and/or Neofabraea based on rot symptoms on apple fruit and colony morphology on potato dextrose agar. A smaller subset of 101 representative isolates was further analyzed by DNA sequencing of the internal transcribed spacer region. Furthermore, partial segments of the β-tubulin gene, the translation elongation factor 1α gene, and the 16S mitochondrial ribosomal RNA gene were studied. The phylogenetic analyses, including sequences of reference species, showed that P. vagabunda is the dominant species associated with bull's eye rot of apple in the study area, whereas Neofabraea kienholzii was found only on a small number of apple fruit samples. The combination of multilocus sequence data revealed 11 unique genotypes that belonged to P. vagabunda and four to N. kienholzii. To the best of our knowledge, this study is the first to report N. kienholzii as a postharvest pathogen of apple in Italy. Finally, a pathogenicity test demonstrated different degrees of virulence among selected isolates of P. vagabunda and N. kienholzii on the cultivar Golden Delicious. The present study emphasizes the importance of accurate species identification, because different species may vary in their biological and pathogenic characteristics, and consequently require distinct disease management strategies, both in the field and during the postharvest stages.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Citrinin Mycotoxin Contamination in Food and Feed: Impact on Agriculture, Human Health, and Detection and Management Strategies.

Citrinin (CIT) is a mycotoxin produced by different species of Aspergillus, Penicillium, and Monascus. CIT can contaminate a wide range of foods and feeds at any time during the pre-harvest, harvest, and post-harvest stages. CIT can be usually found in beans, fruits, fruit and vegetable juices, herbs and spices, and dairy products, as well as red mold rice. CIT exerts nephrotoxic and genotoxic effects in both humans and animals, thereby raising concerns regarding the consumption of CIT-contaminated food and feed. Hence, to minimize the risk of CIT contamination in food and feed, understanding the incidence of CIT occurrence, its sources, and biosynthetic pathways could assist in the effective implementation of detection and mitigation measures. Therefore, this review aims to shed light on sources of CIT, its prevalence in food and feed, biosynthetic pathways, and genes involved, with a major focus on detection and management strategies to ensure the safety and security of food and feed.

Metabolic Effects of Violet Light on Spoilage Bacteria from Fresh-Cut Pakchoi during Postharvest Stage.

Pakchoi (Brassica rapa L. Chinensis) is an important vegetable in Asia. Pseudomonas palleroniana is one of the specific spoilage organisms (SSOs) of fresh-cut pakchoi. The purpose of this study was to investigate changes to the endogenous metabolic spectrum of violet light (405 nm) with regard to food spoilage bacteria from fresh-cut pakchoi using ultrahigh-performance liquid chromatography-tandem mass spectrometry. In this study, P. palleroniana samples were treated with violet light at 4 °C, and the maximum dose was 133.63 J/cm2. The results revealed that 153 metabolites and 83 pathways significantly changed compared to the control group, which indicated that light treatment may lead to ROS accumulation in cells, inducing oxidative stress and the excessive consumption of ATP. However, the increased content of aromatic amino acids and the decreased anabolism of some amino acids and nucleotides might be a form of self-protection by reducing energy consumption, thus contributing to the improvement of the tolerance of cells to illumination. These results provide new insights into the antibacterial mechanism of P. palleroniana with regard to metabolism.

First Report of Anthracnose Caused by Colletotrichum tabaci on Green Pepper (Capsicum annuum) in China.

Vitamins, capsaicin and capsochrome are abundant in pepper (Capsicum annuum), a fruit that is also used as a spice. During hot and rainy seasons, anthracnose disease caused by Colletotrichum spp. affects pepper crops and causes significant yield losses in the pre- and post-harvest stages(Liu et al. 2016). Unidentified disease spots were discovered on peppers leaves in a field in Wei yuan (35°8'10" N, 104°12'54" E), Gansu Province, China, in September 2019. The diseases was found to have a 100% incidence in a 0.07-ha area, which drew our attention. The lesions were mostly found in the middle and upper parts of the leaves, and the symptoms mostly showed up as roughly circular patches on the leaves with dark brown, and yellowish center. 18 tissues with a diameter of 1 cm were obtained from the line between healthy and diseased portions. They were sterilized for 45 s in 1% mercuric chloride, then rinsed 5 times in sterile distilled water and dried with sterile filter paper. After 4 days of culture on a plate with a PDA media 5 strains were recovered from the treated tissue. Healthy pepper plants grown in the lab were inoculated with conidia suspension (50 mL, 107 conidia/mL) for pathogenicity while sterile distilled water was used as control. Each treatment had three duplicates. Leaves infected with the BYL strain 16 days later showed obvious symptoms, which were comparable to those found in the field. The control leaves showed no sign of disease. The pathogen was re-isolated from the infected pepper leaves and it had the same features as strain BYL. Koch's postulate was proven correct. The BYL colony started out white, then turned gray-brown with black sclerotia in the center. Conidia were hyaline, smooth, cylindrical, typically straight, with rounded ends, and ranged in size from11.754-16.477(14.587±0.139×2.833-4.220(3.348±0.037) μm. Appressoria solitary or in loose clusters, 6.910-9.078×5.386-7.119 μm in size, medium brown, smooth-walled, ellipsoidal or irregular in form, with noticeable piercing pore with dark halo. The isolate was identified as Colletotrichum species based on the morphological characteristics (Damm et al. 2014).It was then re-identified using multi-molecular analysis. To amplify and sequence of the isolates, the genes ITS, TUB2, CHS1, ACT, GAPDH and HIS3 were employed (Weir et al. 2012, Crous et al. 2004). They were deposited in GenBank (MW581857 for ITS, MW595706 for ACT, MW595707 for CHS1, MW595708 for GAPDH, MW595709 for HIS3, and MW595710 for TUB2). The sequence of ITS, ACT, CHS1, and HIS3 in GenBank were found to be 100% identical to those of Colletotrichum tabaci (JQ005763 for ITS, KM105414 for ACT, JQ005784 for CHS1 and KM105346 for HIS3). The primers GAPDH and TUB2 amplified a gene sequence that was 99% identical to Colletotrichum tabaci in GenBank (KM105559 for GAPDH and JQ005847 for TUB2). Based on appearance and sequencing analysis, the isolate was identified as Colletotrichum tabaci. The optimal light condition for BYL growth was 12 h light/12 h dark cycle, temperature 30 o C, pH 8, sucrose as carbon source, and yeast extract as nitrogen source according to the biological features. Colletotrichum tabaci caused anthracnose in peppers in the field. This is the first report of Colletotrichum tabaci causing anthracnose in peppers in China that we are aware of.