Horticulturae, Volume 7, Issue 10 (October 2021) – 87 articles

Cut flowers have become an export income in the global floriculture market. They have multiple uses, such as for home beautification, in ceremonies (including weddings and funerals), and as symbols of love, appreciation, respect, etc., in humane society. Each type of cut flower has a different vase life and the longevity of their freshness is linked to preharvest, harvest, and postharvest tools and conditions. The postharvest quality and vase life must be considered in order to obtain the desirable qualities of cut flowers, and factors that affect this are important in the floral industry. The use of floral preservative solutions is good practice for prolonging the vase life of cut flowers. Currently, the eco-friendly solutions, which are used as floral preservatives for extending cut flower vase life, have been discovered to be a low-cost and organic alternative as compared to chemical solutions. However, there are certain problems associated with the use of chemical and eco-friendly solutions. In this review, we summarize several potential approaches to improve flower vase life and discuss the best choices for holding-preservative-solution practices. Full article

The Brazilian Cerrado is the second largest Brazilian biome. In recent decades, a reduction in rainfall has indicated an extension of the dry season. Among the many native species of the Cerrado of the Annonaceae family and used in folk medicine, Annona crassiflora Mart. has fruits of high nutritional value and its by-products are sources of bioactive compounds, such as alkaloids. The aim of the study was to investigate how water stress impacts the production of alkaloids. The study was carried out in a nursery, and the knowledge was flood, field capacity and drought. Gas exchange, chlorophyll a fluorescence, antioxidant enzymes, total soluble sugars, starch, reducing sugars, sucrose, total alkaloids and liriodenine were analyzed. We observed that plants subjected to drought had an increase in the production of total alkaloids and liriodenine, without a reduction in photosynthetic metabolism. Plants kept under drought and flood conditions dissipated higher peroxidase activity, while catalase was higher in flooded plants. Starch showed the highest concentration in flooding plants without differing from drought plants; the lowest trehalose concentrations were found in both drought and flooding plants. The drought stimulated the synthesis of total alkaloids and liriodenine without reducing the primary metabolism, which suggests adaptation to Cerrado conditions. Full article

This work investigated the structural, biochemical, and molecular characteristics of grape skin cell wall during ripening, related to susceptibility to Botrytis cinerea. The comparative study between the two main grape cultivars in Champagne region, Pinot noir and Chardonnay, quantified: (1) the maturity and physical profile of grape skin; (2) the morphological characteristics; (3) soluble pectic polysaccharides located in grape skin cell walls; and (4) the gene expression of the two main degrading enzymes (VvPME1 and VvPG1) and PME activity. During the maturation period, the grape skins of the two cultivars appear different in their structure and composition. Chardonnay is characterized by higher relative humidity (RH) and level of VvPG1 expression, lower disease incidence and penetrometry values, and thicker cell walls than Pinot noir skins. Thus, the cell wall composition is sufficiently different between grape varieties from the same area to allow their discrimination and could be used to better manage the harvest date. Full article

Germins and germin-like proteins (GLPs) are glycoproteins closely associated with plant development and stress response in the plant kingdom. Here, we carried out genome-wide identification and expression analysis of the GLP gene family in cucumber to study their possible functions. A total of 38 GLP genes were identified in cucumber, which could be mapped to six out of the seven cucumber chromosomes. A phylogenetic analysis of the GLP members from cucumber, Arabidopsis and rice showed that these GLPs could be divided into six groups, and cucumber GLPs in the same group had highly similar conserved motif distribution and gene structure. Gene duplication analysis revealed that six cucumber GLP genes were located in the segmental duplication regions of cucumber chromosomes, while 14 genes were associated with tandem duplications. Tissue expression profiles of cucumber GLP genes showed that many genes were preferentially expressed in specific tissues. In addition, some cucumber GLP genes were differentially expressed under salt, drought and ABA treatments, as well as under DM inoculation. Our results provide important information for the functional identification of GLP genes in the growth, development and stress response of cucumber. Full article

Simulated impact damage testing was investigated by fractal image analysis using response surface methodology (RSM) with a central composite design (CCF) on quality of ‘Glom Sali’ guava for drop heights (0.2, 0.4, and 0.6 m), number of drops (1, 3, and 5) and storage temperature conditions (10, 20, and 30 °C). After 48 h, impacted fruit were determined and analyzed for bruise area (BA), bruise volume (BV), browning index (BI), total color difference (∆E), image analysis for bruise area (BAI), and fractal dimension (FD) at the bruising region on peeled guava. Results showed that the correlation coefficient (r = −0.6055) between ∆E and FD value was higher than ∆E and either BA (r = 0.3132) or BV (r = 0.2095). The FD variable was determined as a better indicator than conventional measurement (BA or BV) for pulp browning and impact bruising susceptibility. The FD variable also exhibited highest R²_adj value (81.69%) among the other five variables, as the highest precision model with high determination coefficient value (R²_adj) (>0.8) for impact bruising prediction. Recommended condition of the FD variable to minimize impact bruising was drop height of 0.53 m for five drops under storage at 30 °C. FD variable assessed by image analysis was shown to be a highly capable measurement to determine impact bruising susceptibility in guava fruit. Full article

Tea [Camellia sinensis (L.)] plants are important economic crop in China. Chilling stress and freezing damages have seriously affected the quality of tea products that have been already regarded as the main restricting factors to industry’s development. Nitric oxide (NO) plays a crucial role in resistance of abiotic stresses. An experiment was conducted in an artificial climate chamber to study the effect of NO on tea plants grown under chilling stress (−2 °C) for 0, 6, 24, 48, and 72 h. Foliar application of sodium nitroprusside (SNP) at a rate of 500 μmol·L⁻¹ was used as NO donor. The experiment contained two factors: the first was the foliar application with SNP or distilled water, and the scond one was the chilling (−2 °C) exposure time (0, 6, 24, 48, and 72 h). The effects of NO on membrane lipid peroxidation, osmotic adjustment substances, and antioxidant activity under cold stress were studied. In addition, the gene expression of CsICE1 and CsCBF1 in respond to NO addition were also investigated using real-time polymerase chain reaction (RT-PCR). The results show that foliar addition of NO (500 μmol·L⁻¹ of SNP) reduce the relative conductivity of tea leaves, inhibits the elevated malondialdehyde content, promotes the accumulation of proline, soluble protein and sugar, and increases the superoxide dismutase, catalase activities, thereby alleviates the damage of cold stress on tea leaves. The CsICE1 expression in 500 μM SNP treatment was peaked at 24 h of low temperature stress, while it did not express at normal temperature. Therefore, the current study is considered a good scientific material in understanding how tea plants sense and defense the chilling stress and that plays an important role to improve the level of production and economic benefits. It is also provided significant theory bas to control chilling stress in tea plants. Full article

Moringa oleifera Lam. is a fast-growing and drought-resistant tree of the Moringaceae family. The tree is known with some common names: miracle, ben oil, drumstick, horseradish or simply moringa. The plant grows in a variety of environments including harsh conditions. The plant has a high content of phytonutrients, being used as natural integrators to cure malnutrition. Phytochemical studies of plant organs showed the plant as a rich source of primary and secondary metabolites belonging to different classes of organic compounds. Pharmacological studies confirmed the use of the plant to cure several diseases and to possess nutraceutical properties. This review is aimed to contribute to the knowledge of M. oleifera by providing its plant description, phytochemistry and pharmacology. Full article

Fresh food boxes have been popular in many countries for providing convenience and supporting local production, while the convenient access of various market channels in Taiwan makes it difficult to develop. The COVID-19 events shed light on the opportunity to promote fresh food boxes. Due to the complexity of consumer preferences, it is important to investigate the market opportunity of fresh food boxes. A total of 748 valid survey data were collected throughout Taiwan from July to September in 2019. The analysis of variance and interval regression model with random utility theory was adopted to explore food product preferences and to elicit the maximum budget for the fresh food box. Results show that marrow vegetables, fruits, and meats are the major categories that must be included in the list of the fresh food box. The average maximum budget for a fresh food box is about NTD 702 (about USD 25), while the highest maximum budget can reach up to NTD 1202 (about USD 43) for some potential consumers. Although fresh food boxes have a market opportunity in Taiwan, the market potential may be more focused on those who have online market shopping experiences. Marketers would need more marketing strategies to enhance more potential shoppers to adopt the online purchase for fresh food boxes. Full article

Wedelia chinensis, belonging to the Asteraceae family, has been used in folk medicine in East and South Asia for the treatment of common inflammatory diseases and protection against liver toxicity. Previously, in vitro propagation through different tissue explants has been reported, including through nodal segments, axillary buds, and shoot tips, whereas leaf segments failed to proliferate. Here, we report on the in vitro propagation of W. chinensis by culturing young leaf explants in MS medium supplemented with 0.5 mg/L α-naphthaleneacetic acid (NAA), 0.75 mg/L thidiazuron (TDZ), 1 mg/L gibberellic acid (GA₃), 3.75 mg/L adenine, 3% sucrose, and 0.8% agar at pH 5.8. Calli were observed in all explants derived from the youngest top two leaves, and the average percentage of shoot regeneration was 23% from three independent experiments. Then, several shoots were excised, transferred onto MS basal medium supplemented with 3% sucrose and 0.8% agar at pH 5.8, and cultured in a growth chamber for 1 to 2 months. Roots were easily induced. Finally, plantlets carrying shoots and roots were transferred into soil, and all of them grew healthily in a greenhouse. No morphological variation was observed between the regenerated plantlets and the donor wild-type plants. In addition, we also established root cultures of W. chinensis in culture medium (MS medium, 3 mg/L NAA, 3% sucrose, pH 5.8) with or without 0.8% agar. To the best of our knowledge, this is the first paper reporting plant regeneration from leaf explants in the herbal plant W. chinensis. Full article

Vase life is one of the most important factors that determines the marketability of cut flowers and is greatly affected by the water balance. The vase life of cut hydrangea flowers varies greatly depending on the postharvest solution management. Therefore, this study investigated the vase life of freshly harvested hydrangea (Hydrangea macrophylla ‘Verena’) according to the three types of preservative solutions (tap water (TW), 1% Chrysal Professional Ⅲ (CPⅢ), 2% sucrose + 250 mg/L 8-hydroxquinoline + 100 mg/L citric acid (SHQC)) and the combination solutions (pretreatment; TW, 0.1% Chrysal RVB (RVB), Floralife Quick Dip (FQ), transport; TW, CPⅢ, Floralife Clear (FC), preservative; CPⅢ, FC) for each distribution stage (pretreatment–transport–consumer). In the preservative comparison experiment, compared with the control, SHQC and CPⅢ significantly increased the vase life in 2019 (0.7 days, 3.4 days) and 2020 (1.4 days, 3.1 days), respectively. In the comparative experiment, by solution combination, the group (RVB, FQ) using the pretreatment significantly extended the vase life by 5.9 days and 4.6 days compared with the TW. These results confirm the importance of preservative solutions and pretreatment, suggesting that appropriate pretreatment and preservatives should be used to improve the marketability of cut hydrangea flowers. Full article

(1) Background: This special issue contains new developments in the field of fresh produce quality. Freshness provides the appeal for the consumer to purchase a particular horticultural produce. Freshness is a combination of size, colour, shape, flesh firmness, turgescence and glossiness without wilting, which imply that the produce has been picked only a short while ago and has not suffered any decay during harvest, transport or storage. (2) Objective: The objective of the present work was to develop potential freshness indices. The indices are based on non-invasive, real-time measurements, using changes in surface appearance after harvest, using Bell pepper as the most difficult model. (3) Methods: The selection criteria were a dramatic change in values over 14 days of storage at 17 °C, and either a consistent decrease or increase without peaks and troughs. Only two (out of five) non-invasive techniques were selected, i.e., surface glossiness, measured non-destructively using a luster sensor (type CZ-H72 from Keyence Co., Osaka, Japan) and light reflection spectra, recorded by a spectrometer, whereas the three techniques fruit firmness (penetrometer), colorimeter (e.g., Minolta) and false colour images (profilometer) were excluded. (4) Results: The first technique based on fruit glossiness provides luster values depending on fruit colour. Green Bell pepper fruit with a Fresh Index in excess of 463–490 a.i. can be classified as fresh, and similarly of 525–565 a.i. for yellow and 486–502 a.i. for red pepper fruit. This first Freshness index dropped, indicating a lesser freshness, to less than 100 a.i. after 14 days storage, irrespective of fruit colour, thereby providing a suitable wide, ca. 5-fold, range of parameterization. The second index is based on the difference between the light reflectance peaks at 630–633 nm and at 500 nm, also measured perpendicular to the convex fruit side. These percentage values decreased from >40% with fresh red and yellow Bell pepper to ca. 20% after 14 days storage; similarly, these percentages decreased from ca. 16% to ca. 8% in green pepper fruit, in both cases by a twofold factor. Overall, a third Freshness index could be a combination of luster values larger than 470 a.u. and >40% difference of the light reflectance between 630 nm and 500 nm. (5) Conclusions: Two viz three freshness indices are proposed and thresholds elaborated for Bell pepper fruit. The analysis showed that both indices viz technologies, luster and light reflection spectra, require colour differentiation, i.e., a specific index for yellow, red and green Bell pepper fruit. Full article

Perilla frutescens var. crispa (Pfc) of the family Lamiaceae is used as a medicinal plant due to its pharmacological properties. Although Pfc is an important resource for the medical nutrition industry, the variability in phytonutrients and biological activities among genotypes of Pfc is not well understood. The effects of genotype on the phytochemical composition, antioxidant activities, antimelanogenic principles, and anti-inflammatory effects of Pfc were determined using eight Pfc genotypes. Using HPLC analysis, we identified 30 polyphenolic compounds from Pfc, although variation was observed in the polyphenolic composition of Pfc genotypes. Pfc 5 exhibited antimelanogenic activity in B16F10 melanoma cells via inhibition of tyrosinase activity. In addition, Pfc 2 strongly inhibited lipopolysaccharide-induced nitric oxide production through translational downregulation of inducible NOS in RAW264 murine macrophages. Taken together, the results of our study reveal the significant impacts of genotype on phytonutrients and biological activities. This finding will assist in the breeding and genetic engineering of Pfc in order to meet future phytonutrition and health challenges. Full article

Auxin response factors (ARFs) are a transcription factor family that regulates the expression of auxin phase-responsive genes. Here, we performed a genome-wide investigation of the tetraploid blueberry (Vaccinium corymbosum cv. ‘Draper’) genome sequence. Physical and chemical properties, phylogenetic evolution, gene structure, conservative motifs, chromosome location, and cis-acting elements of blueberry ARF genes were comprehensively evaluated. A total of 70 blueberry ARF genes (VcARF) were found in its genome, which could be divided into six subfamilies. VcARF genes were unevenly distributed on 40 chromosomes and were observed to encode protein sequences ranging in length from 162 to 1117 amino acids. Their exon numbers range from 2 to 22. VcARF promoter regions contain multiple functional domains associated with light signaling, aerobic metabolism, plant hormones, stress, and cell cycle regulation. More family members of VcARF genes were discovered in blueberry than in previously studied plants, likely because of the occurrence of whole-genome duplication and/or tandem duplication. VcARF expression patterns were analyzed at different stages of fruit development, and VcARF3, VcARF4, VcARF14, VcARF37, and VcARF52 were observed to play important roles. VcARF3 and VcARF4 appeared to function as repressors, while VcARF14 acted as an essential factor in fruit firmness differences between firm and soft flesh cultivars. Full article

The present research was aiming to study In-Silico the effect of Glycyrrhizic Acid ammonium salt (GAS) and Salicylic acid (SA) on the coat protein of potato leafroll virus (PLRV). In addition, in-vitro studying the effect of (GAS NPs) and Salicylic acid (SA NPs) nanoparticles at concentrations 0.15, 0.30, 1.25 and 2.5 mM, respectively, to control, decline or reduce the presence of PLRV in potato plants Solanum tuberosum L. selena. (GAS NPs) and (SA NPs) were applied in the MS medium at concentrations 0.15, 0.30, 1.25 and 2.5 mM, respectively. Results revealed that, enhancement or decline the PLRV according to the initiation of specific pathways. The expression level of Kinase 3 gene increased significantly due to the two used concentrations of GAS NPs. While the expression of callose gene was upregulated significantly in response to treatment of PLRV infected plant with (GAS NPs) with concentration (0.30 mM). Treatment with (SA NPs) caused upregulation significance only of callose gene at (2.5 mM) concentration. The molecular modeling results of used compounds (glycyrrhizic acid ammonium salt and salicylic acid) showed highest score of binding and the best rms define value with a very good binding mode and perfect interactions with amino acids of the three subunits (A, B and C) forming the protein coat of leaf roll virus. Glycyrrhizic acid ammonium salt and salicylic acid nanoparticles could be perfect solution to produce potato plant free virus in-vitro. Further larger studies are needed to investigate the role of the studied compounds in vivo. Full article

Ethylene production is negatively associated with storage life in sand pear (Pyrus pyrifolia Nakai), particularly at the time of fruit harvest. 1-Aminocyclopropane-1-carboxylic acid synthase (ACS) is the rate-limiting enzyme in ethylene biosynthesis and is considered to be important for fruit storage life. However, the candidate ACS genes and their roles in sand pear remain unclear. The present study identified 13 ACS genes from the sand pear genome. Phylogenetic analysis categorized these ACS genes into four subgroups (type I, type II, type III and putative AAT), and indicated a close relationship between sand pear and Chinese white pear (P. bretschneideri). According to the RNA-seq data and qRT-PCR analysis, PpyACS1, PpyACS2, PpyACS3, PpyACS8, PpyACS9, PpyACS12 and PpyACS13 were differently expressed in climacteric and non-climacteric-type pear fruits, ‘Ninomiyahakuri’ and ‘Eli No.2’, respectively, during fruit ripening. In addition, the expressions of PpyACS2, PpyACS8, PpyACS12 and PpyACS13 were found to be associated with system 1 of ethylene production, while PpyACS1, PpyACS3, and PpyACS9 were found to be associated with system 2, indicating that these ACS genes have different roles in ethylene biosynthesis during fruit development. Overall, our study provides fundamental knowledge on the characteristics of the ACS gene family in sand pear, in addition to their possible roles in fruit ripening. Full article

This study evaluated the effect of preharvest treatments with salicylates (salicylic acid (SA), methyl salicylic acid (MeSA) and acetyl salicylic acid (ASA)) on fruit quality parameters and primary and secondary metabolites during ripening at five sampling dates. The results showed that salicylates affect overall fruit quality, and some very desirable and important properties of strawberry fruits were acquired by the treatments, such as a deeper red colour (decreased hue angle), delayed ripening process with maintenance of higher fruit firmness, and higher sugar and ascorbic acid content. HPLC-MS analysis of the phenolic contents showed at almost all sampling dates that treatment with salicylates increased the content of some phenolic groups, the contents of the hydroxycinnamic acids (SA: up to 18%; MeSA: up to 13% increase), flavanols (SA: up to 27%, MeSA: up to 36% and ASA: up to 24% increase), anthocyanins (SA: up to 51%, MeSA: up to 33% and ASA: up to 28% increase) and also flavonol glycosides such as flavones. Total phenolics in fruits also increased-up to 27% with SA and up to 28% with MeSA. In general, better fruit quality and higher metabolite content were obtained with SA. Full article

Water stress is the most critical aspect restricting the development of agriculture in regions with scarce water resources, which requires enhancing irrigation water-saving strategies. The current work discusses the potential application of the plant-strengthening root endophyte Piriformospora indica against moderate (25% less irrigation water) and severe (50% less irrigation water) water stress in comparison to the optimum irrigation conditions of greenhouse cucumbers. P. indica improved growth, nutrient content, and photosynthesis apparatus under normal or water-stress conditions. On the other hand, moderate and severe water stress reduced yield up to 47% and 83%, respectively, in non-colonized cucumber plants, while up to 28 and 78%, respectively, in P. indica-colonized plants. In terms of water-use efficiency (WUE), P. indica improved the WUE of colonized cucumber plants grown under moderate (26 L/kg) or severe stress (73 L/kg) by supporting colonized plants in producing higher yield per unit volume of water consumed by the crop in comparison to non-colonized plants under the same level of moderate (43 L/kg) or severe (81 L/kg) water stress. Furthermore, P. indica increased the indole-3-acetic acid (IAA) content, activity levels of catalase (CAT) and peroxidase (POD) with an apparent clear reduction in the abscisic acid (ABA), ethylene, malondialdehyde (MDA), proline contents and stomatal closure compared to non-stressed plants under both water-stress levels. In addition, chlorophyll a, b, a + b contents were increased in the leaves of the colonized plants under water-stress conditions. This improvement in chlorophyll content could be correlated with a significant increment in the transcripts of chlorophyll biosynthesis genes (protochlorophyllide oxidoreductase [POR], chlorophyll a oxygenase [CAO]) and a reduction in the chlorophyll degradation genes (PPH, pheophorbide a oxygenase [PAO], and red chlorophyll catabolite reductase [RCCR]). In conclusion, P. indica has the potential to enhance the cucumber yield grown under moderate water stress rather than severe water stress by improving WUE and altering the activity levels of antioxidant enzymes and chlorophyll metabolism-related genes. Full article

The content and component of glucosinolates in edible stems and leaves of eight Chinese kale varieties from Japan and eight varieties from China were determined by HPLC-MS. Simultaneously, the expression levels of glucosinolate biosynthesis pathway genes from four varieties with high and low total glucosinolate contents were analyzed by the qRT-PCR method. Four types of aliphatic glucosinolates (A-GLSs: GRA, SIN, GNA and GER) and indole glucosinolates (I-GLSs: 4-HGBS, GBS, 4-MGBS and NGBS) were detected in the stems and leaves of 16 varieties, and no aromatic glucosinolates (R-GLSs) were detected. A-GLSs account for more than 80.69% of the total content of total glucosinolates (T-GLSs), in which GNA and GRA are the main components of stems and leaves. Among Japanese varieties, QB1 has higher content of A- and T-GLSs, while that of XLB was lower; however, the corresponding varieties were ZH and DSHH in Chinese varieties. Among the above four varieties, the expression levels of SOT16, CYP83B1, SOT17, CYP83A1 and MAM1 genes were significantly higher in the varieties with higher GLSs; the expression levels of SOT16 and CYP83B1 were consistent with the content of I-GLSs; and SOT17, CYP83A1 and MAM1 expression levels were consistent with A-GLSs content. At the same time, the expression levels of SOT16 and CYP83B1 in the leaves were higher than those in the stems. CYP83A1 and MAM1 genes were less expressed in the leaves than in the stems of lower content varieties. It is speculated that these genes may be the key genes regulating GLS biosynthesis in Chinese kale. Full article

Due to the potential to enhance soil productivity and plant growth, biological fertilizers have recently been considered an alternative source for soil, water, and crop-contaminating chemical fertilizers in sustainable agriculture. The importance of different fertilizer sources on quantitative and qualitative traits of Syrian cephalaria (Cephalaria syriaca L.) was explored in an experiment based on a randomized complete block design during the 2015–2016 growing season. The maximum grain yield (9.97 g/plant) and biological yield (24.57 g/plant) were obtained from the application of Azotobacter + chemical fertilizer treatment, but the maximum oil percentage (25.23%) and oil yield (2.41 g/plant) were observed in the plants treated with Azotobacter + vermicompost. The plants treated with Azotobacter + chemical fertilizer exhibited the highest 1000 seed weight (15.03 g). Application of Azotobacter + vermicompost increased chlorophylls a, b, and total by 2.06, 1.96, and 4.02% versus Azotobacter treatment alone, respectively. The treatment of Azotobacter + manure increased total phenol, flavonoids, and DPPH antioxidant activity by 27.89, 0.56, and 53.16% versus the treatment of Azotobacter + chemical fertilizer. The integrated application of different fertilizer sources had an optimal effect on the uptake of trace elements (Cu, Fe, and Zn) so that the treatment of Azotobacter + vermicompost increased their concentrations. Due to the positive effect of integrated application of different fertilizer sources on improving the studied traits of Cephalaria, it is recommended to replace chemical fertilizers with combined fertilizers including organic and biological inputs to enhance the efficiency of crops, reduce environmental pollution, and move towards sustainable agriculture. Full article

The feasibility of utilising spent mushroom substrates (SMSs) as a growing medium component for Pleurotus ostreatus cultivation was investigated. P. ostreatus was cultivated on traditional wheat straw (control) and wheat straw substrate supplemented with SMSs from Pholiota nameko (N-SMS), Hypsizygus marmoreus (M-SMS), and Hericium erinaceus (E-SMS) in varying supplementation rates (10%, 20%, and 30%). The yield, biological efficiency (BE), dry matter, and protein content of P. ostreatus fruiting bodies grown on ten substrates were evaluated. Significant differences in yield, BE, protein content, and dry matter of P. ostreatus were found among the studied substrates. The highest yield was recorded in 20% E-SMS (254.33 g), 20% N-SMS (253.43 g), and 10% E-SMS (251.67 g). The biological efficiency ranged from 66.48% (30% M-SMS) to 72.67% (20% E-SMS) and followed a similar trend to yield. The highest protein content was recorded in 30% M-SMS (29.93 g∙100 g dry weight⁻¹). The highest dry matter of P. ostreatus was noticed in 30% of M-SMS (23.74 g) and 10% of M-SMS (23.06 g). Therefore, the spent mushroom substrates of Ph. nameko, H. marmoreus, and H. erinaceus could be used as a potential, low-cost sustainable alternative (10–30%) and as a renewable component of traditional growing media for P. ostreatus cultivation. Full article

Jojoba seeds have a unique storage lipid wax which is suitable as a basic feedstock in the chemical industry. For saving both human health and the environment, there is a continuous need to search for alternative safe natural sources of plant nutrients. Therefore, in this study the effect of mycorrhizal fungi and Moringa oleifera leaves extract on growth, flowering, fruits set, yield and the chemical composition of the jojoba shrub was studied. The application of a combination of treatments of 20 g L⁻¹ mycorrhizal fungi plus 30 g L⁻¹Moringa oleifera leaves extract recorded the maximum mean values of main branch length, length of secondary branches, number of branched nodes, number of secondary branches, flowering percentage, final fruit set percentage, seeds yield per shrub and per hectare, percentage of minerals, proteins as well as oil yield per shrub and per hectare, chlorophyll a and b, N, P, K percentage with a minimum mean value of the number of days until full bloom in both seasons. The maximum percentage of Gadoleic fatty acid was found with the combination treatment of uninoculation plus 10 g L⁻¹Moringa oleifera leaves extract. Full article

Arbuscular mycorrhiza and Trichoderma are well-known beneficial fungi whose plant growth promotion and defense elicitation effects are known. However, the molecular and biochemical processes underlying the beneficial effects of these priming microorganisms have not been fully elucidated yet. On this basis, the present work aimed to use metabolomics to dissect comprehensively the modulation of secondary metabolism induced by mycorrhiza and Trichoderma, using tomato as a model plant. To this aim, either mycorrhiza or Trichoderma were applied to tomato roots at transplanting using a commercial formulation and then harvested once the mutualistic relationship was well established. Shoots were analyzed using an MS-based untargeted metabolomics approach, and differential metabolites identified by multivariate statistics were subjected to pathway analysis. Together with promoting plant growth, the treatments induced a broad molecular reprogramming with the phenylpropanoid biosynthetic pathway (including defense phenolics like coumarins and glycosylated anthocyanins) being strongly elicited. An accumulation of auxins, cytokinins, and jasmonate (especially after treatment with Trichoderma) could be observed concerning phytohormone profiles. Overall, the broad and distinctive effects triggered by mycorrhiza and Trichoderma in tomato secondary metabolism supported both plant growth promotion and immunity. Full article

The study of morpho-anatomical aspects, metabolic changes of proteins, antioxidant substances, as well as phenolic compounds in embryogenic callus (EC) and degenerative embryogenic callus (DEC) was the aim of the present investigation. Ability to form somatic embryos (SEs) was associated with the softness of the EC, which exhibited a white or creamy color and was composed of isodiametric cells containing dense cytoplasm, conspicuous nuclei and minimal vacuoles with observed mitotic activity. Furthermore, protein, reduced glutathione (GSH) and ascorbic acid (ASC) concentrations and the ratio between ASC and dehydroascorborbic acid (DHA) were increased significantly in the EC in comparison to the DEC. In addition, the phenolic extract of the EC was proved to have higher scavenging activity than the extract from the DEC. A loss of embryogenic competence in the DEC was correlated with the presence of more rigid clumps and such calli had a yellowish to brown color and no cell division could be observed in the cells of such aggregates as the cells had large vacuoles and they have very thick walls. Moreover, these morphological and anatomical observations of the DEC were accompanied by accumulations of the oxidized form of ascorbic acid (DHA), H₂O_2, total soluble phenolic compounds and overaccumulation of naringenin. Alternations in cellular metabolism can affect and regulate the morphogenesis of somatic embryos. Full article

The efficiency of different thermal insulation covers in minimizing temperature fluctuations in cool chain management was investigated to reduce postharvest loss and maintain okra quality during storage and transportation. The four thermal insulation covering materials: (1) heat reflective sheet with thin nonwoven (HRS + TNNW), (2) heat reflective sheet with thick nonwoven (HRS + TKNW), (3) metalized Tyvek^® (MTyvek) and (4) metalized foam sheet (MFS) were studied and compared with perforated linear low-density polyethylene (P-LLDPE) as the typical handing package for okra distribution alongside no covering as the control. The material properties, transpiration rate, vital heat, temperature profiles (air and pulp temperatures), relative humidity, mass loss and incidence of decay were determined throughout a simulated supply chain. Results exhibited that HRS + TNNW and HRS + TKNW covers had the lowest thermal heat energy (Q_x) and moderate R-value. These two covers maintained low temperature fluctuation with the lowest rate of air and pulp temperature changes, reflecting in lowest mass loss and decay in okra. The HRS + TNNW cover yielded less decay (1%) in okra, compared to commercial covers; MTyvek (16%) and MFS (9%). Results showed that HRS + TNNW exhibited great potential as a thermal insulation cover to reduce postharvest loss in okra (5%) compared to typical handling (11–18%) and could be considered as alternative material to reduce the use of foam sheets in cool chain management distribution packaging of okra under ambient environment conditions. Full article

Recently, grafting has been used to improve abiotic stress resistance in crops. Here, using watermelon ‘Zaojia 8424’ (Citrullus lanatus) as scions, three different gourds (Lagenaria siceraria, 0526, 2505, and 1226) as rootstocks, and non-grafted plants as controls (different plants were abbreviated as 0526, 2505, 1226, and 8424), the effect of cold stress on various physiological and molecular parameters was investigated. The results demonstrate that the improved cold tolerance of gourd-grafted watermelon was associated with higher chlorophyll and proline content, and lower malondialdehyde (MDA) content, compared to 8424 under cold stress. Furthermore, grafted watermelons accumulated fewer reactive oxygen species (ROS), accompanied by enhanced antioxidant activity and a higher expression of enzymes related to the Calvin cycle. In conclusion, watermelons with 2505 and 0526 rootstocks were more resilient compared to 1226 and 8424. These results confirm that using tolerant rootstocks may be an efficient adaptation strategy for improving abiotic stress tolerance in watermelon. Full article

Increasing temperature leads to intensive water evaporation, contributing to global warming and consequently leading to drought stress. These events are likely to trigger modifications in plant physiology and microbial functioning due to the altered availability of nutrients. Plants exposed to drought have developed different strategies to cope with stress by morphological, physiological, anatomical, and biochemical responses. First, visible changes influence plant biomass and consequently limit the yield of crops. The presented review was undertaken to discuss the impact of climate change with respect to drought stress and its impact on the performance of plants inoculated with plant growth-promoting microorganisms (PGPM). The main challenge for optimal performance of horticultural plants is the application of selected, beneficial microorganisms which actively support plants during drought stress. The most frequently described biochemical mechanisms for plant protection against drought by microorganisms are the production of phytohormones, antioxidants and xeroprotectants, and the induction of plant resistance. Rhizospheric or plant surface-colonizing (rhizoplane) and interior (endophytic) bacteria and fungi appear to be a suitable alternative for drought-stress management. Application of various biopreparations containing PGPM seems to provide hope for a relatively cheap, easy to apply and efficient way of alleviating drought stress in plants, with implications in productivity and food condition. Full article

Phytophthora spp. are one the most common soil-borne pathogens in citrus crops, in which Phytophthoranicotianae and P. citrophthora are the most relevant species, causing disease problems worldwide, such as foot rot and gummosis of the trunk, branch canker, brown rot of fruit, feeder root rot in orchards, and seedling damping-off in nurseries. Phytophthora-tolerant citrus rootstocks are essential for its control and for the success of the citrus industry. The aim of this study was to determine the susceptibility of new citrus rootstocks with low HLB incidence to Phytophthora diseases. Thus, plants of several commercial and new citrus rootstocks originating in different breeding programs were inoculated with an isolate of P. nicotianae. Thirty days post inoculation (DPI), the damage of lesion length in stem was measured for each plant. These results displayed a different susceptibility response to the damage caused by P. nicotianae among the citrus rootstocks tested. Thus, eleven new citrus rootstocks (B11R3T25, B11R5T25, B11R5T49, B11R5T60, B11R5T64, N40R1T18, N40R1T19, N40R3T25, WGFT + 50-7, UFR-6, and CL-5146), which have not been previously studied against Phytophthora diseases, improved the tolerance effect of Carrizo citrange. Our findings provide useful information for citrus growers on rootstock selection to address incidence problems caused by Phytophthora spp. Full article

This work compares the tolerance to long-term anoxia conditions (35 days) of five new citrus ‘King’ mandarin (Citrus nobilis L. Lour) × Poncirus trifoliata ((L.) Raf.) hybrids (named 0501XX) and Carrizo citrange (CC, Citrus sinensis (L.) Osb. × Poncirus trifoliata (L.) Raf.), the widely used citrus rootstock in Spain. Growth parameters, chlorophyll concentration, gas exchange and fluorescence parameters, water relations in leaves, abscisic acid (ABA) concentration, and PIP1 and PIP2 gene expressions were assessed. With a waterlogging treatment, the root system biomass of most hybrids went down, and the chlorophyll a and b concentrations substantially dropped. The net CO₂ assimilation rates (An) and stomatal conductance (g_s) lowered significantly due to flooding, and the transpiration rate (E) closely paralleled the changes in g_s. The leaf water and osmotic potentials significantly increased in most 0501 hybrids. As a trend, flooding stress lowered the ABA concentration in roots from most hybrids, but increased in the leaves of CC, 05019 and 050110. Under the control treatment (Ct) conditions, most 0501 hybrids showed higher PIP1 and PIP2 expressions than the control rootstock CC, but were impaired due to the flooding conditions in 05019 and 050110. From this study, we conclude that 0501 genotypes develop some adaptive responses in plants against flooding stress such as (1) stomata closure to prevent water loss likely mediated by ABA levels, and (2) enhanced water and osmotic potentials and the downregulation of those genes regulating aquaporin channels to maintain water relations in plants. Although these traits seemed especially relevant in hybrids 050110 and 050125, further experiments must be done to determine their behavior under field conditions, particularly their influence on commercial varieties and their suitability as flooding-tolerant hybrids for replacing CC, one of the main genotypes that is widely used as a citrus rootstock in Spain, under these conditions. Full article

This work evaluated the efficacies of different coatings: chitosan, gelatin and chitosan-gelatin applied layer-by-layer (LbL); for maintaining the quality of sweet peppers that were stored for 3 weeks at a sub-optimal temperature (1.5 °C) and at an optimal storage temperature (7 °C). After the cold-storage period, fruits were kept under marketing conditions (21 °C) for 3 more days. An edible chitosan coating (2%) effectively alleviated chilling injury and the incidence of decay, and also preserved the nutritional quality of sweet peppers that were kept for 3 weeks at 1.5 °C plus 3 more days at 21 °C. The chitosan coating was more effective than the two other coatings. All three coating treatments significantly reduced external CO₂ production, as compared to uncoated control fruit. Storage temperatures did not significantly affect external CO₂ production, although CO₂ production was slightly higher at 1.5 °C. The chitosan coating exhibited good CO₂ gas permeability properties and the peppers coated with that material had lower respiration rates than those in the other two experimental treatments or the control. From a practical point of view, chitosan coating could replace the plastic bags previously found to alleviate chilling injury in peppers that are stored at 1.5 °C as a quarantine treatment. Full article

Fruit extracts of Sambucus nigra L. (elderberry) and Punica granatum L. (pomegranate) have several applications in nutraceutical, cosmetics, and pharmaceutical industries thanks to their richness in antioxidant polyphenols, whose composition changes with the extraction method applied. We aimed to compare the efficiency of the fermentation extraction, recently applied by industries, with the ultrasound-assisted extraction–UAE, a well-known and efficient technique, on the yield of antioxidant polyphenols from elderberry fruits and pomegranate fruit-peels. Extracts were obtained by both methods, analyzed by high-performance liquid chromatography (HPLC) and the antioxidant capacities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Hydroxyl Radical Scavenging (HRS) assays. The main compounds detected in elderberry were caffeoyl and quercetin derivatives, present in higher amounts in UAE extracts. In pomegranate, punicalagin were the main constituents, also detected in higher contents in the UAE extracts compared to fermented ones. The UAE was more suitable for extracting anthocyanins from pomegranate. In addition, higher antioxidant capacities were observed in UAE extracts, possibly due to their richness in polyphenols. Therefore, despite the recent wide applicability and the good performance of the fermentation process, the UAE may be considered more efficient for the extraction of polyphenols from S. nigra and P. granatum fruits and may be used to obtain polyphenolic antioxidant extracts to be applied by several industries. Full article