Bananas are one of the most crucial fruit crops worldwide and significantly contribute to food security in developing countries. However, blood disease of bananas caused by Ralstonia syzygii subspecies celebensensis has become a threat to banana production. Rapid and accurate diagnosis of BDB for on-site detection is pivotal at an early stage for an effective disease control strategy. This study developed LAMP with specific primers targeting BDB, followed by a flocculation assay for visualising positive amplification in the LAMP assay. The assay was sensitive to picogram amounts of gDNA (0.5 pg). LAMP assay on BDB gDNA showed flocculation, but negative results on Fusarium oxysporus cubense and Ralstonia solanacearum confirming the specificity of the assays. Field testing conducted at MARDI headquarters and Taman Pertanian Universiti discovered that the LAMP-flocculation assays were successful in detecting BDB on symptomatic samples as well as on samples from a healthy plot with no symptom observed at the sampling stage, revealing that this assay can detect BDB at an early infection stage. The validation results showed that the LAMP-flocculation assay was comparable with the PCR technique. This newly developed technique is highly specific and sensitive for the early detection of BDB for the adoption of precautionary control measures. Full article

Flowering dogwood (Cornus florida L.) is a popular, spring-blooming ornamental tree native to the eastern United States. The species is in general very susceptible to powdery mildew caused by Erysiphe pulchra, which disfigures leaves, decreases growth, and negatively affects flowering. Breeding for resistance has been recognized as an ideal strategy for controlling the disease in C. florida, but efforts have been hindered by the rarity of PM resistance in available germplasm and knowledge of its genetic control. In this study, we mapped quantitative trait loci (QTL) associated with PM resistance/tolerance in two full sibling populations segregating for PM response: Rutgers H4AR15P25 (P25) × Rutgers H4AR15R28 (P28) (n = 195) and Rutgers H4AR15R25 × Rutgers H4AR15P35 (P35) (n = 83). High-density genetic linkage maps were constructed for the mapping populations using double digest restriction-site associated DNA sequencing-derived single nucleotide polymorphisms (SNPs) and simple sequence repeats (SSRs). The P25 × P28 map consisted of 2265 markers, spanning 1520 cM and 11 linkage groups (LGs) with an average marker spacing of 0.69 cM. The P25 × P35 map was constructed with 1788 markers, spanning 1256 cM and 11 LGs, with an average marker spacing of 0.72 cM. The maps had 604 markers in common and exhibited excellent collinearity. Through multiple QTL model mapping, one major QTL (LOD = 11.36 and R² = 58.9%) was identified in P25 × P35. Furthermore, a minor QTL (LOD = 3.30 and R² = 7.8%) was detected in P25 × P28. Due to their proximity onLG3, these QTL may be designating the same locus or tightly linked loci. The negative additive effects of both QTL signify that the PM susceptible male parents were contributing susceptibility alleles to the progeny. This is the first report of QTL associated with PM response on LG3 in C. florida and lays the groundwork for the development of marker-assisted selection for PM resistance in C. florida breeding programs. Full article

Powdery mildew disease caused by Oidium neolycopersici is one of the major diseases affecting tomato production in South Africa. Interestingly, limited studies exist on how this disease affects the community structure microbial communities associated with tomato plants employing shotgun metagenomics. In this study, we assess how the health status of a tomato plant affects the diversity of the rhizosphere microbial community. We collected soil samples from the rhizosphere of healthy (HR) and diseased (DR; powdery mildew infected) tomatoes, alongside bulk soil (BR), extracted DNA, and did sequencing using shotgun metagenomics. Our results demonstrated that the rhizosphere microbiome alongside some specific functions were abundant in HR followed by DR and bulk soil (BR) in the order HR > DR > BR. We found eighteen (18) bacterial phyla abundant in HR, including Actinobacteria, Acidobacteria, Aquificae, Bacteroidetes, etc. The dominant fungal phyla include; Ascomycota and Basidiomycota, while the prominent archaeal phyla are Thaumarchaeota, Crenarchaeota, and Euryarchaeota. Three (3) bacteria phyla dominated the DR samples; Bacteroidetes, Gemmatimonadetes, and Thermotoga. Our result also employed the SEED subsystem and revealed that the metabolic pathways involved were abundant in HR. The α-diversity demonstrates that there is no significant difference among the rhizosphere microbiomes across the sites, while β-diversity demonstrated a significant difference. Full article

Attempts were undertaken to design a quick ready-to-cook gluten-free snack utilizing finger millet and potato flour (50:50) as well as tomato pomace due to the restricted availability of gluten-free snack goods in the Indian market. The nutritional content of the food and its general acceptability, cooking characteristics, and storage stability were all tested. The addition of tomato pomace had a distinct influence on the product’s color and hardness. Additionally, it resulted in a significant reduction in the amount of oil used, cooking loss, and frying time required. With a high acceptance level, the snack supplemented with 10% tomato pomace was determined to be the most optimal formulation. When the same substance was subjected to FTIR analysis, it was discovered that it retained all the important functional groups required for sustaining antioxidant activity. It also displayed high storage stability, a desirable overall acceptance score, and a very promising nutritional profile, all of which would benefit the product’s end users. Full article

In olive (Olea europaea L.), the floral quality is a key feature affecting the final fruit crop. The aim of this study was to evaluate the inflorescence traits and the floral quality parameters of three clones of Leccino cultivar (L 1.3, L 1.4, L 1.9). To assess a possible effect of light limitations on these parameters two canopy zones, internal (IZ) and external (EZ), were considered. The inflorescences were collected over two consecutive years in order to establish: (i) the characteristics of inflorescences (length, flowers per inflorescence) and flowers (open and perfect flowers); (ii) the ovary structure by histological analysis; and (iii) the viability and germination of pollen grains by in vitro culture. The preliminary results highlighted some differences among clones. The L 1.9 was the less affected by the canopy position for inflorescence morphological traits, and the presence of ovaries with at least three fully developed ovules denoting a high female fertility. Regardless of the canopy position, L 1.4 showed the highest pollen viability, suggesting its possible use as pollinator. The lower sensitivity of female and male floral organs to partial shading of L 1.9 and L 1.4 needs further investigations aimed at evaluating their suitability in high-density olive orchards. Full article

Plants are a reservoir of phytochemicals, which are known to possess several beneficial health properties. Along with all the secondary metabolites, polyphenols have emerged as potential replacements for synthetic additives due to their lower toxicity and fewer side effects. However, controlling microbial growth using these preservatives requires very high doses of plant-derived compounds, which limits their use to only specific conditions. Their use at high concentrations leads to unavoidable changes in the organoleptic properties of foods. Therefore, the biochemical modification of natural preservatives can be a promising alternative to enhance the antimicrobial efficacy of plant-derived compounds/polyphenols. Amongst these modifications, low concentration of ascorbic acid (AA)–Cu (II), degradation products of ascorbic acid (DPAA), Maillard reaction products (MRPs), laccase–mediator (Lac–Med) and horse radish peroxidase (HRP)–H₂O₂ systems standout. This review reveals the importance of plant polyphenols, their role as antimicrobial agents, the mechanism of the biochemical methods and the ways these methods may be used in enhancing the antimicrobial potency of the plant polyphenols. Ultimately, this study may act as a base for the development of potent antimicrobial agents that may find their use in food applications. Full article

Sour cherry (Prunus cerasus L.), having a rich composition of biologically active connections and antioxidants, is gaining increasing popularity among agricultural producers. Increasing the production of sour cherry fruits requires the introduction of modern technology, one of the elements of which is low-growing rootstocks. For many cultures, the use of low-growing rootstocks has been widely studied, but there is very little information on their use in cherry plantations. We studied new varieties and rootstocks of cherries in the conditions of the dry steppe zone, where this issue had not been studied before. Sour cherry (Prunus cerasus L.) varieties—Toy, Memory of Zhukova, and Loznovskaya—are the most adapted to the conditions in which the experiments were conducted. Russian breeding forms (Krymsk, Krasnodar region), which were taken as rootstocks, are widely used for sweet cherries (Prunus avium L.), but are practically never used for sour cherries (Prunus cerasus L.). The influence of rootstocks on such parameters as drought resistance, heat resistance, winter hardiness, and productivity was studied in variety–rootstock combinations. The study showed that they had the greatest drought resistance, and accordingly affected the grafted variety with rootstock, in the pedigree of which there are wild species. These rootstocks were of the VSL and RVL series. The study of the productivity of variety–rootstock combinations showed that in the grafted varieties the most rapid entry into the fruiting season and the greatest increase in the yield was facilitated by the rootstock forms of VSL-1 and VSL-2 (K5) which made it possible to obtain a yield of 5.8–8.1 kg/tree, depending on the variety grafted onto them. However, it is necessary to continue the research that has been started in order to fully determine the possible qualitative and quantitative parameters of the studied variety–rootstock combinations and to identify the most promising ones for further introduction into industrial production. This work was carried out within the framework of the topic of the state task of the Scientific Research Center of Agroecology of the Russian Academy of Sciences No. 0713-2019-0009: “Theoretical foundations, creation of new competitive biotypes of agricultural crops with high productivity, quality, sustainability and varietal technologies based on the latest methods and technological solutions in a changing climate, including seed breeding and nursery breeding”. Full article

Evidence have indicated that RR-type MYB-related transcription factors (TFs) are functionally diverse in regulating floral development, fruit development, leaf senescence, ABA response, and drought and salt responses. Several RR-type MYB-related TFs in Arabidopsis, Antirrhinum and rice are identified and characterized. However, the complete RR-type MYB-related family in tomato has not been studied to date. Here, a genome-wide identification of tomato RR-type MYB-related TFs (SlMYBR) was performed by bioinformatics analysis, and their expression patterns were analyzed. A total of thirteen SlMYBR genes, which were mainly distributed in the head or tail of the chromosome, were identified from tomato and were divided into three groups. Group II was all MYBR genes from eudicots without genes from monocots. For Group I and Group III, the phylogenetic tree was in accord with the evolutionary relationship of these species. SlMYBR proteins were unstable proteins and located in the nucleus. The promoters of SlMYBR contained multiple important cis-acting elements related to abiotic stress or hormone responses. SlMYBR genes had various temporal and spatial expression patterns. Experiments of spraying exogenous hormone demonstrated that the expression of most genes containing hormone response elements was changed, indicating that the expression patterns were associated with the amount of cis-acting elements. The comprehensive investigation of tomato SlMYBR genes in the present study helps to clearly understand the evolution of RR-type MYB-related TFs and provides a useful reference for the further functional study of SlMYBR genes in tomato. Full article

In order toexplore the regulation mechanism of macadamia fruitlet abscission induced by ‘starvation stress’, a treatment of girdling and defoliation was applied to the bearing shoots of macadamia cultivar ‘H2’ at the early stage of fruit development, simulating the starvation stress induced by interrupting carbon supply to fruit. The levels of carbohydrates, hormones, and related gene expression in the different tissues (husk, seed, and pedicel) were investigated after treatment. The results showed that a severe fruit drop occurred 3~5 d after starvation stress treatment. The contents of glucose, fructose, and sucrose in both the husk and the seed were significantly decreased, as well as the fructose and sucrose in the pedicel; this large reduction occurred prior to the massive fruit shedding. Starvation stress significantly reduced the GA₃ and ZR contents and enhanced the ABA level in the pedicel and the seed, whereas it did not obviously change these hormones in the husk. After treatment, IAA content decreased considerably in both the husk and seed but increased remarkably in the pedicel. In the husk, the expression of genes related to sugar metabolism and signaling (NI, HXK2, TPS, and TPP), as well as the biosynthesis of ethylene (ACO2 and ACS) and ABA (NCED1.1 and AAO3), was significantly upregulated by starvation stress, as well as the stress-responsive transcription factors (AP2/ERF, HD-ZIP12, bZIP124, and ABI5), whereas the BG gene associated with ABA accumulation and the early auxin-responsive genes (Aux/IAA22 and GH3.9) were considerably suppressed during the period of massive fruit abscission. Similar changes in the expression of all genes occurred in the pedicel, except for NI and AP2/ERF, the expression of which was significantly upregulated during the early stage of fruit shedding and downregulated during the period of severe fruit drop. These results suggest that complicated crosstalk among the sugar, IAA, and ABA signaling may be related to macadamia fruitlet abscission induced by carbohydrate starvation. Full article

The goal of this Special Issue, entitled “Soil, Water and Nitrates Management in Horticultural Production”, is to examine recent advances in horticultural practices and strategies that can contribute to maintaining or increasing soil fertility and the efficiency of water and nitrogen use [...] Full article

Mulching significantly increases the crop yield and quality by positively affecting the physical features of the soil. The effect of multiple mulching treatments on soil temperature, yield, and nutrient composition of green asparagus grown in a plastic tunnel was assessed. Two mulch materials: transparent plastic film (PF) and rice husk (RH), were applied and compared with non-mulching treatment (CK). The soil temperatures at the soil surface and 10 cm below it were generally higher in the PF mulch than in the CK during the spring. PF mulch accelerated early spear emergence and growth, which led to harvesting 16 days earlier than in the CK. Under the PF mulch, the early yield of spears increased by 26.6% from January to the end of March, and the annual gross income by 14.8% because of the higher price resulting from the significantly higher marketable spear length and diameter; however, they were reduced in the RH mulch. Most nutrient compositions, such as soluble sugar, ascorbic acid, rutin, flavonoid content, and total antioxidant activity, were significantly increased in the PF mulch treatment. PF mulch might benefit green asparagus production during early spring because of its ability to promote early spear emergence and growth. Full article

Citrus essential oils (EOs) are widely used as flavoring agents in food, pharmaceutical, cosmetical and chemical industries. For this reason, their demand is constantly increasing all over the world. Besides industrial applications, the abundance of EOs in the epicarp is particularly relevant for the quality of citrus fruit. In fact, these compounds represent a natural protection against postharvest deteriorations due to their remarkable antimicrobial, insecticidal and antioxidant activities. Several factors, including genotype, climatic conditions and cultural practices, can influence the assortment and accumulation of EOs in citrus peels. This review is focused on factors influencing variation of the EOs’ composition during ripening and on the implications on postharvest quality of the fruit. Full article

Lycium schweinfurthii is a traditional medicinal plant grown in the Mediterranean region. As it is used in folk medicine to treat stomach ulcers, it took more attention as a source of valuable secondary metabolites. The in vitro cultures of L. schweinfurthii could be a great tool to produce secondary metabolites at low costs. The presented study aimed to introduce and optimize a protocol for inducing callus and cell suspension cultures as well as estimating phenolic, flavonoid compounds, and antioxidant activity in the cultures of the studied species. Three plant growth regulators (PGRs) were supplemented to MS medium solely or in combination to induce callus from leaf explants. The combination between 2,4-dichlorophenoxy acetic acid (2,4-D) and 1-naphthyl acetic acid (NAA) induced callus in all explants regardless of the concentration. The highest fresh weight of callus (3.92 g) was obtained on MS medium fortified with 1 mg L⁻¹ of both 2,4-D and NAA (DN1) after 7 weeks of culture. DN1 was the best medium for callus multiplication regarding the increase in fresh weight and size of callus. Otherwise, the highest phenolics, flavonoids, and antioxidant activity against DPPH free radicals were of callus on MS fortified with 2 mg L⁻¹ NAA (N2). The cell suspension cultures were cultivated on a liquid N2 medium with different sucrose concentrations of 5–30 g L⁻¹ to observe the possible effects on cells’ multiplication and secondary metabolite production. The highest fresh and viable biomass of 12.01 g was obtained on N2 containing 30 g L⁻¹ sucrose. On the other hand, the cell cultures on N2 medium of 5 and 30 g L⁻¹ sucrose produced phenolics and flavonoids, and revealed antioxidant activity against DPPH and ABTS⁺ free radicals more than other sucrose concentrations. The presented protocol should be useful in the large-scale production of phenolic and flavonoid compounds from callus and cell cultures of L. schweinfurthii. Full article

Brazil is one of the three largest beer producers in the world. Four basic ingredients are needed as raw material for the production of beer: water, malt, yeast, and hops (Humulus lupulus L.). Until recently, almost all of the hops in Brazil were imported from other countries. However, in the last decade, hop cultivation in Brazil has emerged due to the increase in the number of new craft breweries, which have demanded diversified raw material for the production of various types of beer. Hops is considered a short-day, temperate species, so the major challenge for the development of hop cultivation in Brazil, with high-yield capacity and with local typicity of bitterness and aroma, is the adaptation of cultivars to the photoperiod conditions in subtropical regions. This review addresses the history of hop cultivation in Brazil and characterizes the main climatic elements of three emerging subtropical growing regions located at different latitudes, such as air temperature, photoperiod, solar radiation, and water availability, to provide support for the development of new technologies for hop cultivation, including supplemental lighting, irrigation, and mulching. Full article

This study examined the photosynthetic responses of two sunflower hybrids to elevated temperatures and excess light intensity in the flowering stage by measuring the chlorophyll a fluorescence (ChlF) under morning and afternoon field conditions to determine the photosynthetic pigment contents and the relative accumulation of photosynthetic proteins. The morning environmental conditions were considered optimal, while the afternoon was characterised by elevated temperatures and excess light intensity. The minimum fluorescence intensity (F₀), the electron-flux-reducing end electron acceptors at the photosystem I acceptor side per reaction centre (RE₀/RC), and the D1 protein had significant, high, and positive correlations with the environmental conditions, which indicates that they were the most useful in the sunflower-stress-response research. In hybrid 7, the elevated temperatures and the excess light intensity resulted in the inactivation of the oxygen-evolving complex, which was indicated by the positive L, K, and J steps, the increase in the maximum quantum yield of PSII (TR₀/ABS), the decrease in the electron transport further than the primary acceptor Q_A (ET₀/(TR₀-ET₀)), the reduction in the performance index (PI_ABS), and the higher relative accumulation of the light-harvesting complex of the photosystem (LHCII). Hybrid 4 had smaller changes in the fluorescence curves in phases O–J and J–I, and especially in steps L, K, J, and I, and a higher PI_ABS, which indicates a more efficient excitation energy under the unfavourable conditions. As the tested parameters were sensitive enough to determine the significant differences between the sunflower hybrids in their photosynthetic responses to the elevated temperatures and excess light intensity in the flowering stage, they can be considered useful selection criteria. The development of more adaptable sunflower hybrids encourages sustainable sunflower production under stressful growing conditions. Full article