Horticulturae

Gibberellins (GAs) are plant hormones indispensable in regulating the growth and development of fruits. Recent studies have shown that GAs play important roles in delaying horticultural crop ripening and senescence, enhancing the internal and external quality of horticultural crops and resistance to stress and disease. We reviewed the role of GAs in the postharvest physiology of fruits in recent years. GAs are closely related to their ability to retard fruit senescence. GAs could effectively improve fruit storage quality and significantly increase flesh hardness, reduce respiration intensity, inhibit the release of endogenous ethylene, and effectively inhibit fruit softening and ripening. It can also improve the intrinsic and extrinsic quality of fruit storage by improving fruit shape, regulating color, delaying the reduction of soluble solids, promoting sugar accumulation, and delaying vitamin loss. GAs also play a role in postharvest biotic and abiotic stress resistance. The GA treatment effectively reduces the cold damage index, reduces the production and accumulation of superoxide anion(O₂⁻), improves the antioxidant capacity of fruits, and maintains the integrity of cell membranes during low-temperature storage. Moreover, GAs could effectively control some postharvest fruit diseases. In conclusion, GAs play an important role in the physiological regulation of postharvest fruits and have important application prospects in postharvest fruits. Full article

Chemical profiling the sage essential oils (SEOs) from wild and cultivated (shaded or non-shaded) plants has been investigated. The yield of SEOs from wild plants (3.51 mL/100 g) was higher than that from cultivated plants(shaded plants: 3.20 mL/100 g and non-shaded plants: 2.56 mL/100 g).The main components of SEO from wild plants were cis-thujone (43.2%), camphor (17.6%), 1,8-cineole (13.8%), veridiflorol (3.8%) and borneol (3.4%).The chemical composition of SEO from cultivated plants included camphor > cis-thujone > 1,8-cineole. Net shading lowered the content of toxic cis-thujone in sage (23.5%) and is therefore recommended in order to achieve better quality of SEO compared to non-shaded plants (cis-thujone 28.3%).The thujone content of SEO from wild plants is much higher (43.2%), and this drastically reduces the quality of EO. Cultivated sage was found to have stronger antioxidant activity (shaded plants 6.16 mg/mL or non-shaded 7.49 ± 0.13 mg/mL) compared to wild sage plants (9.65 mg/mL). The isolated SEOs are good sources of natural antioxidants with potential applications in the food and pharmaceutical industries. Full article

Ethylenediaminetetraacetic acid (EDTA), when used as a main chelator for complex plant microfertilizers, causes many negative environmental effects; therefore, new compounds or new use of the known compounds to replace EDTA have been widely studied. In the present study, biodegradation rate, plant (Raphanus sativus) growth stimulation and ecotoxicity towards Daphnia magna and Chlorella vulgaris of iminodisuccinic acid (IDS), considered as an alternative for EDTA in agriculture, has been investigated. It was demonstrated that IDS’ biodegradation rate over 28 days was 28.1%, which is 4.5 times higher than that of EDTA. Similar to EDTA, complexation with metals led to an increase in the degradation rate by 1.8-fold. The majority of compounds were degraded within first 7 days. The GI values for IDS implemented at concentrations of 100 mg/L (both in pure form and in combination with microelements) were 2.4–2.6 times higher than those of EDTA. The ecotoxicity index EC10 of IDS was estimated to be 2.0 g/L and 5.8 g/L towards D. magna and Ch. vulgaris which are 4.1- and 10-fold higher than those for EDTA, respectively. It can be concluded that IDS is a promising agent to chelate microelements used in plant nutrition. Full article

‘Arrayana’ mandarin is one of the most cultivated citrus species in Colombia, but this fruit has a short postharvest life and is sensitive to chilling injury (CI) during cold storage. Generating strategies that decrease CI to mandarin can reduce quantitative and qualitative losses postharvest. Brassinosteroids (BR) have been used as a sustainable technology to alleviate CI in fruits and improve postharvest quality. This study evaluated the effect of applying the 24-epibrasinolide analogue (EBR), at doses of 5 mg L⁻¹; DI-31 analogue, at 5 and 10 mg L⁻¹; and control, on the main physical and biochemical characteristics of ‘Arrayana’ mandarin stored at 4 °C for 40 days and, subsequently, 7 days at room temperature (shelf life). The application of EBR and DI-31 analogues reduced the appearance of CI in the exocarp of ‘Arrayana’ mandarin fruits by reducing electrolyte leakage, maintaining membrane integrity, and increasing antioxidant activity and phenol content at the end of cold storage and shelf life. This was especially pronounced with 5 mg L⁻¹ of EBR. Similarly, the BR maintained the postharvest quality of mandarins by reducing weight loss, respiratory intensity, and chlorophyll degradation; increasing β-carotene; and maintaining titratable acidity and soluble solids. Our research reports, for the first time, CI tolerance in Arrayana mandarin using natural (EBR) and spirostanic (DI-31) analogues and illustrates the tolerance functionality of the DI-31 analogue on CI in the fruit postharvest. Full article

The environmental impact of food products is significantly affected by their packaging. Therefore, this study aimed to assess the effect of PLA (polylactic acid) film, as an alternative to petroleum-based bags, on the shelf-life of fresh-cut wild rocket and sea fennel grown in a cascade cropping system (CCS). To this end, wild rocket (main crop) was cultivated using either peat or compost as a growing medium. Sea fennel (secondary crop) was subsequently grown in a floating system with leachates from the primary crop as a nutrient solution. The leaves of both crops were harvested and packaged in OPP- (oriented polypropylene) or PLA-based bags and stored for 7 days at 4 °C. The leaves of wild rocket and sea fennel showed lower dehydration and lower respiration when compost was used as a growing medium or leachate. Wild rocket in compost increased in nitrate and vitamin C contents at harvest while leachates had scarce influence on their contents in sea fennel. After storage, regardless of the crop, no relevant detrimental changes were observed on leaves packaged with PLA, being a product microbiologically safer when compared to OPP. The bag type had almost no influence on most relevant phytochemical compounds. In conclusion, the use of a PLA-based film on minimally processed wild rocket and sea fennel leaves is a sustainable alternative to petroleum-based plastic for a short food supply chain. Full article

Chili (Capsicum annuum), economically important, is one of the world’s most popular horticultural plants. Functional biochemical components, such as polyphenol content, antioxidants, and α-glucosidase inhibitory properties, are found in chili. The purpose of this study was to evaluate a chili hybrid that resulted through full diallel crosses for its yield components, total phenolic (TPC) and flavonoid content (TFC), antioxidants, and α-glucosidase inhibitory (AGI) activities. The Folin-Ciocalteu and AlCl₃-colorimetric assays were, respectively, used for TPC and TFC analyses. Using 2,2-diphenyl-1-picrylhydrazy (DPPH) and ferric reducing antioxidant power assay (FRAP) techniques, the antioxidant activity of a sample was determined. The bioassay of α-glucosidase inhibition was used to evaluate the antidiabetic activity of the sample. The twenty-five genotypes (hybrid and parent) have diverse yield components and biochemical contents. The highest fruit weight per plant was found in IPB074005 (1008.85 g). IPB114367 showed a high AGI (80.25%), antioxidant FRAP (43.42 µmol TE g⁻¹ DW), TFC (3.97 mg QE g⁻¹ DW), and TPC (37.51 mg GAE g⁻¹ DW). These findings suggested that hybrid plants that suppress α-glycosidase and oxidative stress may prevent diabetes and its complications. This vital information could help design replacement drugs and diabetes diets. Full article

Affected by global warming, continuous high temperature has a negative impact on plant growth and development and become a major constraint to crop production. Germplasm resource identification has become a research hotspot in many fields, and it is also necessary to establish effective identification methods. In this study, twenty Brassica rapa varieties were selected to investigate the physiological and biochemical characteristics under heat stress, explore the relationship between physiological response and the heat resistance mechanism, and select some typical heat-resistant and heat-sensitive varieties. The effects of photosynthetic electron transfer and antioxidant pathway on the heat resistance of Brassica rapa were identified. These findings will provide important guidance for the physiological regulation and identification method of heat stress in plants. Full article

Plant anthocyanin is a secondary metabolite widely distributed in the roots, stems, leaves, flowers and fruits of plants, and its synthesis is significantly affected by light intensity. To reveal the physiological response mechanism of anthocyanin synthesis in blueberry leaves at different light intensities, four light intensities (100% (CK), 75%, 50% and 25%) were set for the ‘O’Neal’ southern highbush blueberry as the experimental material in our study. The relationship between endogenous hormone contents, key enzyme activities, and variations in the anthocyanin content in blueberry leaves under various light intensities during the white fruit stage (S1), purple fruit stage (S2) and blue fruit stage (S3) of fruit development were studied. The results showed that the anthocyanin content of blueberry leaves increased first and then decreased, and decreased first and then increased with the increase in light intensity and development stage, respectively. The appropriate light intensity could significantly promote the synthesis of anthocyanin, and the anthocyanin content in leaves treated with 75% light intensity was 1.09~4.08 times that of other light intensity treatments. The content or activities of gibberellin (GA₃), indoleacetic acid (IAA), jasmonic acid (JA), abscisic acid (ABA), ethylene (ETH), phenylalanine ammonia lyase (PAL), chalcone isomerase (CHI), dihydroflavonol reductase (DFR) and UDP-glucose: flavonoid 3-glucosyltransferase (UFGT) were significantly or extremely significantly correlated with the content of anthocyanin in leaves. This indicated that light intensity significantly promoted anthocyanin synthesis in blueberry leaves by affecting endogenous hormone contents and key enzyme activities in the anthocyanin synthesis pathway. This study lays a foundation for further research on the molecular mechanism of light intensity regulating anthocyanin synthesis in blueberry leaves. Full article

Key message. The success of interspecific hybridization in hardy geranium (Geranium sp.) can be predicted by considering the genetic distance between parental genotypes and using the logistic regression model developed in this study. Hardy geranium is a popular ornamental plant known for its architecture, hardiness, prolonged flowering, and diverse colors in leaves and flowers. In ornamental breeding, the pursuit of novel trait combinations is never-ending. Even in Geranium, certain combinations of valuable traits have not yet been achieved. Interspecific hybridization can increase diversity; however, success remains low due to pre- and postzygotic barriers. Crossing success can be predicted by response criteria such as pollen tube growth (tube_length), seed development (seed_dev), and seed setting (seed_set). Within a collection of 42 Geranium genotypes and during two consecutive breeding seasons (years), we evaluated tube_length, seed_dev, and seed_set for 150, 1155, and 349 crosses, respectively. These crosses varied in four parental differences (variables): chromosome number (Chrom), DNA/chromosome (DNA), style length (Style), and genetic distance expressed as the Jaccard distance (cJaccard = 1 − Jaccard). Using logistic regression models has confirmed that most often, the success rate decreased with increasing parental distance. The most consistent association was seen in seed_dev in combination with cJaccard. The model was used to predict the number of crosses necessary to have 10 successful crossing products by taking into account the uncertainty in the model. These findings provide valuable guidance for future planning of interspecific breeding experiments in Geranium. By incorporating the genetic distance between parental genotypes, breeders can enhance the efficiency and success of hybridization efforts. Full article

Phytophthora is a genus of destructive plant pathogens. Certain species are damaging to native ecosystems, forestry, and the horticultural sector, and there is evidence of their dissemination in plant imports. Horticultural nurseries are central nodes of the plant trade and previous studies have found a high diversity of Phytophthora associated with plant nursery stock. It was subsequently hypothesized that green waste disposal sites in nurseries could harbour diverse Phytophthora communities and act as a pathogen reservoir and conduit, facilitating further Phytophthora infection of nursery stock and its spread into the wider environment. This project identified Phytophthora species associated with green waste at three Scottish nurseries by sampling material from waste piles, water run-off from piles, and roots from discarded plants. Species were identified using a baiting method and sequencing of environmental DNA. Plant nursery green waste was shown to harbour diverse and varied Phytophthora species assemblages, with differences among nurseries reflecting biosecurity management practices. Eighteen Phytophthora species were detected in the samples, including the highly destructive pathogens P. ramorum and P. austrocedri. Results suggest that the improved management of waste, for example through effective on-site composting, is essential to reduce the risk of Phytophthora pathogens spreading from nurseries into the wider environment. Full article

This study evaluated the effects of raised beds on crop production and quality in home gardens. The crops were grown using optimal management techniques and crop rotation principles based on organic farming. Three experimental versions were compared: V₁ with 40-centimetre-high raised beds, V₂ with 20-centimetre-high raised beds, and V₃ with ground-level beds as the control. The results showed consistent dry weight and moisture content across all three versions for most vegetable varieties. The sweet pepper ‘Barbara’ stood out significantly, as V₃ had the highest dry weight percentage (10.28%) and V₂ had the highest moisture content percentage (93.40%). Nutrient analysis revealed no significant differences in lipid, ash, protein, nitrogen, or caloric value among the different versions of most vegetables. However, version V₃ of the tomato ‘Tigerella’ showed the highest crude fibre content. Variations were observed in lycopene, ß-carotene, and calcium content among different versions of specific vegetables. Anti-nutritive compounds and average yield varied among the experimental versions for certain plant species. These findings have implications for dietary choices and can guide sustainable food production. It is recommended to consider raised beds, particularly V₃, for cultivating sweet pepper ‘Barbara’, and further research is encouraged to explore the potential health benefits of version V₃ of tomato ‘Tigerella’. These insights provide valuable vegetable science and nutrition information and can guide agricultural practices. Full article

The main strawberry cultivars grown in tropical regions originated from breeding programs developed in temperate countries, which limit the expression of their maximum productive potential when grown in warm climates. Additionally, strawberry cultivation in these regions depends almost entirely on imported strawberry young plants, increasing production costs. Obtaining adapted cultivars with a lower requirement for the accumulation of chilling hours is the main objective of breeding programs in the southern hemisphere. Thus, the objective of this study was to evaluate short-day strawberry genotypes, pre-selected based on yield and fruit quality components through multivariate analysis, for cultivation in tropical conditions. Two experiments were performed. In the first one, 36 pre-selected genotypes and their parents were assessed based on productive traits (total fruit mass, commercial fruit mass, and mean mass of commercial fruits), soluble solids content, and fruit firmness. For selection, multivariate analysis was applied using the genotype (ideotype) selection index and principal component analysis. In the second experiment, the fruit of the best-ranked genotypes, the parents, and the Camarosa and Dover cultivars were assessed for soluble solids (SS), titratable acidity (TA), SS/TA ratio, ascorbic acid, phenolic compounds, and total anthocyanins. To identify the most promising genotypes, the data were analyzed using principal component analysis. The RVFS06CR-105, RVDA11CR-61, RVDA11CR-125, and RVCS44CR-130 were the most promising genotypes for cultivation in tropical conditions, based on yield and fruit quality components. The means found for these genotypes were higher than the commercial cultivars Dover, Camino Real, and Camarosa. The use of multivariate analysis was efficient in selecting the genotypes, with repeatability of information between the methods guaranteeing consistency in the information. The selected genotypes had higher yields than those used as the control, which is a promising result considering the independence in relation to genetic material, mainly in the expansion of the cultivation area in the tropical regions of the southern hemisphere. In addition, these genotypes are being evaluated in different tropical climate regions with the aim of validating them for submission to the registration and release process for farmers. Additionally, they are being used as a source of genes for crossings and new selections. Full article

Alternaria brown spot (ABS) is a disease caused by the fungus A. alternata f. sp. citri, which results in lesions on the fruits, leaves, and branches of several mandarin varieties and their hybrids. Due to the high cost of fungicide application, alternative methods for controlling ABS need to be studied. Therefore, this study aimed to evaluate the use of essential oils (EOs) from different mandarin varieties to mitigate the effects of ABS. The inhibitory effect of different concentrations (1, 2, 4, 8, and 16 μL·mL⁻¹) of the EOs of Fremont IAC 543 mandarin, IAC 2019Maria mandarin, Murcott IAC 221 tangor, and Late IAC 855 willowleaf on the in vitro mycelial growth of the fungus A. alternata was evaluated. Additionally, the curative and preventive effects of these EOs on the ABS symptoms in detached leaves of Murcott IAC 221 tangor were also assessed. The EO of IAC 2019 Maria mandarin induced less mycelial growth, and consequently, a greater inhibition of the growth of the fungus A. alternata at a concentration of 16 μL·mL⁻¹. This EO was more effective for control than the other oils tested. In the detached leaf experiment, both the curative and preventive treatments at a concentration of 16 μL·mL⁻¹ showed lower values of disease severity. Full article

Leaf morphology in plants is very important in the evaluation of intraspecific variation. Indeed, the leaves of the fig tree (Ficus carica L.) present a great diversity of shape and size. The present study consists of the botanical, morphological, and morphometric characterization of the leaves of 26 local fig tree varieties cultivated in different areas of Bejaia (northeast Algeria). Our results indicate that the morphological parameters of the leaves allowed a good differentiation of the studied cultivars according to the descriptors (UPOV) among varieties and independent of their growing environment. Moreover, the method of morphometric description proposed in this paper allows the differentiation of varieties and the comparison among them in an objective way and by simple mathematical methods. This method demonstrates the existence of a very high percentage of polymorphisms within the studied varieties, but also their classification according to the number of lobes, the depth of the lateral sinuses, and the degree of openness of the angles performed by the main veins of the leaves. The Azougagh variety is characterized by wider angles, and, on the contrary, the Tassahlit variety has the least-open angles. None of the studied varieties presented “entire” leaves. The majority presented leaves with five lobes. The varieties Tilizwith, Tazarzourth, Avarkan, Tamkarkourth, and Inconnu B differed clearly from the rest by showing leaves with seven lobes and deep lateral sinuses. In contrast, the varieties Zarika, Baccor Blanc, Avarkan Lisse, and Avgaiti presented leaves with only three lobes. This is the first work on fig tree characterization using morphometric methods, which are shown to be complementary to the UPOV code and efficient in separating even the closed varieties. It will be interesting to extend these studies to larger scales and areas. Full article

The tomato brown rugose fruit virus (ToBRFV) causes severe damage to tomato cultivars and has international economic importance. The harmful tobamovirus is easily mechanically transmissible and highly stable. An ongoing cultivation of infected tomato plants may lead to the spread of ToBRFV in and around the production area of the infested tomato farm. We conducted a study in which we collected a representative number of swab samples from various inanimate surfaces in greenhouses, packaging halls, and shared and private accommodations. In addition, numerous fabrics, such as outer clothing, bed linen, and items used by greenhouse workers, were tested. The infectivity of ToBRFV-contaminated surfaces was tested in bioassays using Nicotiana tabacum cv. Xanthi NN and confirmed using DAS-ELISA. The proportion of ToBRFV-contaminated surfaces varied among locations, from 48.7% in greenhouses to 0% in offices with limited access to staff. Samples from shared accommodation and private accommodation were 18.4% and 3.6% ToBRFV positive, respectively. Clothing and protective items were found to be highly contaminated with ToBRFV, and even around the sleeping area, infective ToBRFV was detected in a few apartments. This study provides evidence for the first time on how and where infectious ToBRFV can be spread by humans beyond the production area. To avoid further dissemination, strict hygiene protocols are required to interrupt transmission routes. Full article

Volatiles are important quality components in tea (Camellia sinensis) flowers. Albino tea plants are mutant tea plants with diverse abnormal metabolisms. However, whether the metabolisms of volatiles in tea flowers from albino cultivars are abnormal remains unclear. In this study, headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry and aroma evaluation were conducted to investigate the volatile composition and aroma of tea flowers from three albino cultivars (i.e., Baiye No.1, Huangjinya, and Yujinxiang) and one non-albino cultivar (i.e., Jiukeng). The results indicated that tea flowers shared the majority of volatiles but their relative abundances were different. Twelve differential compounds were screened out by partial least squares discriminant analysis. Linalool was the one with the highest relative abundance in three out of the four tea flowers, while acetophenone was the one with the highest relative abundance in tea flowers from Huangjinya. Aroma evaluation indicated that tea flowers from Huangjinya smelt sweetest among them. Partial least squares regression analysis revealed that acetophenone and (R)-1-phenylethanol were positively associated with the sweet smell, while methyl salicylate, 2-heptanol, (E)-2-hexenal, nonanal, and 2-pentanol were positively associated with the green smell. The results enhance our understanding of the volatiles and aroma of tea flowers from albino cultivars. Full article

‘Giant Green’ is one of the Syzygium samarangense cultivars planted throughout Malaysia because it has great potential for benefitting human health. However, its variation in chemical compounds, especially in the leaves at different maturity stages, cannot be systematically discriminated. Hence, Fourier transform infrared spectroscopy (FTIR) and gas chromatography–mass spectrometry (GCMS) coupled with chemometric tools were applied to discriminate between the different stages of leaves, namely, young, mature, and old leaves. The chemical variability among the samples was evaluated by using principal component analysis (PCA) and hierarchical clustering analysis (HCA) techniques. For discrimination, partial least squares discrimination analysis (PLS-DA) was applied, and then partial least squares (PLS) was used to determine the correlation between biological activities (antioxidant and alpha-glucosidase inhibitory assay) and maturity stages of ‘Giant Green’ leaves. As a result, the PCA, HCA, and PLS-DA of the FTIR and GC-MS data showed the separation between clusters for the different maturity stages of the leaves. Additionally, the PLS result demonstrated that the young leaves showed a strong correlation between metabolite quantities and biological activities. The findings of this study revealed that FTIR and GC-MS coupled with chemometric analyses can be used as a rapid method for the discrimination of bioactive structural functions in relation to their biological activity. Full article

Recent studies using LED lighting at low to modest intensity have indicated that compared with red light, blue light can promote plant elongation in many crops as a shade avoidance response despite varying sensitivity with light environments, plant species, and growth stages. Currently, there is limited understanding of how temperature affects the blue light-mediated plant response. To clarify this point, two microgreen species (arugula and mustard) were grown indoors under two light quality × two temperature treatments: red LED light (peak at 670 nm) and blue LED light (peak at 450 nm) at 18 °C or 28 °C. A photosynthetic photon flux density of 110 µmol m⁻² s⁻¹ and a photoperiod of 12 h d⁻¹ were used for all treatments. After 6 to 8 days of treatment, at both temperatures, blue vs. red light promoted plant elongation, as demonstrated by a greater plant elongation rate, final plant height, and hypocotyl length, in arugula but not in mustard. Blue vs. red light also promoted some shade-avoidance responses such as decreased cotyledon size in both species and increased petiole length and dry mass partitioning to hypocotyls in arugula only. The elongation promotion in arugula by blue light was greater at 18 °C than at 28 °C, showing interactions between light and temperature on most plant traits. For mustard, plant elongation was promoted at 28 °C compared to 18 °C independent of light treatment, showing no interactions between light and temperature on most plant traits. These results suggest that the blue light-mediated elongation as a shade-avoidance response is not reversed by high temperature, despite the varying sensitivity with temperatures and species. Full article

Strawberries are a popular food. However, the growth and reproduction of microorganisms on the surface of strawberries change their quality and may cause food poisoning. We compared the effects of solid lipid nanoparticles containing cinnamaldehyde (SLN-CA) and unencapsulated cinnamaldehyde on the freshness of strawberries stored for seven days. The impacts of SLN-CA at different concentrations on strawberry firmness, weight loss, rate of fruit rot, and sensory quality were investigated at 25 °C. Superoxide dismutase (SOD) and catalase activities and malonaldehyde (MDA) and vitamin C contents of strawberry cell homogenates were measured during storage. The experimental results showed that SLN-CA treatment can effectively reduce the probability of decay in strawberries without causing excessive weight loss. SLN-CA can reduce softening, maintain a high level of SOD activity in cells, reduce the accumulation of MDA and consumption of organic acids, and improve the sensory characteristics of strawberries and thereby their shelf life. Therefore, SLN-CA is a promising preservation method to increase the shelf life and safety of strawberries. Full article