Editor’s Choice Articles

Crassulacean acid metabolism (CAM), one of three kinds of photosynthesis, is a water-use efficient adaptation to an arid environment. CAM is characterized by CO₂ uptake via open stomata during the nighttime and refixation CO₂ via the Calvin cycle during the daytime. Facultative CAM plants can shift the photosynthesis from C₃ to CAM and exhibit greater plasticity in CAM expression under different environments. Though leaf thickness is an important anatomical feature of CAM plants, there may be no anatomical feature changes during the C₃–CAM transition for all facultative CAM plants. The shift from C₃ photosynthesis to CAM in facultative CAM plants is accompanied by significant changes in physiology including stomata opening, CO₂ gas exchange and organic acid fluxes; the activities of many decarboxylating enzymes increase during the shift from C₃ to CAM; the molecular changes occur during the photosynthesis C₃–CAM shift involved DNA hypermethylation, transcriptional regulation, post-transcriptional regulation and protein level regulation. Recently, omics approaches were used to discover more proceedings underling the C₃–CAM transition. However, there are few reviews on the mechanisms involved in this photosynthetic shift in facultative CAM plants. In this paper, we summarize the progress in the comparative analysis of anatomical, physiological, metabolic and molecular properties of facultative CAM plants between C₃ and CAM photosynthesis. Facultative CAM plants also show the potential for sustainable food crop and biomass production. We also discuss the implications of the photosynthesis transition from C₃ to CAM on horticultural crops and address future directions for research. Full article

Water management is a key factor to optimize fruit quality and yield of processing tomatoes which are site-specific and influenced by environmental conditions e.g., soil, temperature, precipitation. The aim of this study was to evaluate the efficacity of a low-cost wireless soil moisture sensor in determining the irrigation level for optimizing the marketable yield, fruit quality and economic profit of processing tomato. A two-years (2017–2018) trial was conducted in open field, applying nine drip irrigation levels controlled by wireless soil moisture capacitance sensors. The irrigation levels were as follows: 13.2, 16.7, 25.4, 33.3, 50.0, 62.3, 82.5, 100 and 186.8% of water restitution based on soil moisture sensor readings. Because of the crop stress induced by heavy rainfalls occurring in 2018 growing season, total and marketable yields reached higher maximum values in 2017 than 2018. In 2017, total and marketable yields were maximized by supplying 92.8% and 96.2% of irrigation level, respectively. Moreover, 95.6% and 91.2% of irrigation level were necessary in 2018 to maximize total and marketable yield, respectively. In both growing seasons, marketable yield variation was due to changes of both fruit number and fruit mean weight. Total soluble solids of fruit juice linearly decreased by increasing the irrigation level with a more pronounced effect in the driest growing season (2017). Economic analysis demonstrated that 100% of irrigation level should be preferred by the Italian farmers since it maximized the operating margins of processing tomatoes in both years. To conclude, the use of the tested low-cost wireless soil moisture sensor is an effective tool to manage the level of irrigation and optimize the processing tomato yield and economic benefits for farmers. Full article

The article presents the results of the study of fifty populations of common heather (Calluna vulgaris (L.) Hull) collected throughout its range. A phased comparative analysis (genetic, biochemical, anatomical, morphological, and ecological) was carried out with the estimation of indicators that included two key populations—Zavodouspenskoe (Pritobolye, Western Siberia) and Luga (Baltic, Eastern Europe). It was concluded that heather growing in Western Siberia should be identified as a separate taxonomic group, giving it the status of a subspecies. The gene pool of Pritobolye populations (including Zavodouspenskoe) is represented by the completely dominant (100%) monohaplotype S, which is not found anywhere else. The heather plant growing in Zavodouspenskoe has a longer lifespan. It is distinguished by larger linear leaf dimensions (length 2.06 ± 0.09 mm), thicker cuticle (4.77 ± 0.33 μm), increased number of trichomes (18.98 ± 0.56), and a reduced number of stomata (13.60 ± 0.63) than that growing in Luga. The new subspecies differs in biochemical composition: twice less content of epicatechin (average 1.992 ± 0.005 mg g⁻¹), three times more myricetin (average 2.975 ± 0.005 mg g⁻¹), twice as much chlorogenic acid (average 2.763 ± 0.004 mg g⁻¹). An ecological feature is that C. vulgaris does not grow in the swamps of Western Siberia and has a small population. This species has a high horticultural potential and requires protection as its population in Western Siberia continues to decline rapidly. Full article

The use of rootstocks tolerant to water stress in pepper crops is a complementary technique for saving irrigation water without affecting yields by means of particular rootstock physiological traits, which changes the scion’s perception stress. The present study aimed to analyze the morphological and physiological adaptation of the ‘Cuerno’ pepper cultivar grafted onto tolerant rootstock NIBER^® subjected to capacitance sensor-based deficit irrigation. The stomatal conductance, relative water content and leaf water potential parameters were used to confirm the degree of crop stress. Leaf dry weight and root volume were higher in the grafted plants under the control irrigation and stress treatment conditions. Total fresh root biomass and root volume percentage of grafted plants under water stress were 24% and 33% higher, respectively, than the ungrafted plants. The grafted plants subjected to both water stress and control conditions had a higher marketable production than the ungrafted plants. The higher yields obtained using tolerant rootstocks were explained by the reduced blossom-end rot incidence. Full article

Heterosis is an important phenomenon for high-yield crop breeding and is utilized for breeding F₁ varieties in horticultural crops. However, its molecular mechanism has not been elucidated, and compared to cereals, heterosis is less explored at the molecular level in horticultural crops. In this review, we compiled the new genetic and epigenetic studies on heterosis in horticultural crops. Because of the difficulty of predicting the level of heterosis from the parental genetic distance, molecular approaches are being used to study its molecular basis in horticultural crops. Transcriptome analyses in vegetables have identified photosynthesis-related genes as important in heterosis. Analysis of noncoding RNAs has suggested their involvement in regulating the heterosis of vegetative and fruit tissues. Quantitative trait locus (QTL) analysis has revealed the association of heterozygosity of a specific locus or multiple loci with heterosis of vegetative and fruit tissues. A higher level of DNA methylation was noted in the heterotic F₁ of Brassica rapa leafy vegetables, while the roles of other epigenetic modifications such as histone marks have not been explored. Full article

Liquid spray pollination (LSP) is widely used in fruit tree pollination. However, the LSP parameters that affect the pollen activity are still unclear. In this study, three LSP parameters that mainly affect the pollen activity were studied: storage time of pollen suspensions, sprayer parameters and unmanned aerial vehicle sprayer (UAVS) downwash airflow. In addition, sprayer parameters include the recirculation device, pump type, spraying pressure, nozzle size and revolutions per minute (rpm) of the rotary atomizer (RA). The results showed that, with the exception of nozzle size and UAVS downwash airflow, the pollen activity was significantly influenced by LSP parameters. The mean pollen activity decreased by 20.20% when the pollen suspension was stored for 30 min compared to 0 min. The activity of pollen in the tank was dramatically reduced using the recirculation device. The mean pollen activity decreases as the pump production maximum pressure increases. The mean pollen activity decreased from 40.7% to 29.02% when the spraying pressure increased from 0.3 MPa to 2.5 MPa. Additionally, the mean pollen activity decreased from 44.25% to 14.14% as the rpm of RA increased from 3000 rpm to 14,000 rpm. Our study demonstrated that pollen activity would be ensured by appropriate LSP parameters. This study provides a reliable theoretical basis for optimizing and advancing pear LSP technology. Full article

Soilless crop production is spread worldwide. It is a cultivating technique that enhances yield quality and quantity, thus contributing to both food safety and food security. However, in closed-loop soilless crops, the risk of spreading soil-borne pathogens through the recycled nutrient solution makes the establishment of a disinfection strategy necessary. In the current study, sodium hypochlorite was applied to the recycled nutrient solution as a chemical disinfectant to assess its impact on plant growth, leaf gas exchange, fruit yield, tissue mineral composition, and possible accumulation of chlorate and perchlorate residues in tomato fruits. The application of 2.5, 5, and 7.5 mg L⁻¹ of chlorine three times at fortnightly intervals during the cropping period had no impact on plant growth or gas exchange parameters. Furthermore, the application of 2.5 mg L⁻¹ of chlorine led to a significant increase in the total production of marketable fruits (total fruit weight per plant). No consistent differences in nutrient concentrations were recorded between the treatments. Moreover, neither chlorate nor perchlorate residues were detected in tomato fruits, even though chlorate residues were present in the nutrient solution. Therefore, the obtained tomatoes were safe for consumption. Further research is needed to test the application of chlorine in combination with crop inoculation with pathogens to test the efficiency of chlorine as a disinfectant in soilless nutrient solutions. Full article

As global warming increases day/night temperatures as well as frequencies of heat waves, studying physiological responses in long-term heat stress is required for sustainable yield production in the future. In this study, effects of long-term heat stress on photosynthetic, morphological, and yield parameters of three cherry tomato accessions, HR17, HR22, and HR24, were evaluated. The experiment was conducted under two temperature greenhouse conditions, where temperature set-point for ventilation was 30 °C and 35 °C during the day for 57 days, respectively. Plants were harvested on the 35th days and 57th days after heat treatments, and their physiological and morphological characteristics and yield traits were measured. Under control conditions, HR17 and HR22 had 0.5–0.6 harvest index, while HR24 had 0.3 harvest index. On 35th days after heat treatment, although yield loss percentage of HR17 was high (43%), it produced the highest fruit yield among all three accessions. However, after longer heat treatment, HR24 produced the highest fruit yields among all accessions with the smallest yield loss (34%). Furthermore, yield loss was highly associated with reductions in nitrogen use efficiency and water content in plant body under heat stress. The results of this study will provide breeders with a new insight into selecting heat-tolerant genotypes in cherry tomatoes. Full article

Citrus scion/rootstock combinations alter the concentration of bioactive compounds in orange juice. The shelf life of freshly squeezed juice can be maximized through packaging and storage. The profiles of ascorbic (AA), dehydroascorbic acid (DHAA), and phenolic compounds were analyzed in juices of four sweet orange scions, Sanguínea de Mombuca (SM), Rubi (R), Lue Gin Gong (LGG), and Valência Delta Seedless (VDS), grafted onto ‘Rangpur’ lime (RL) and ‘Swingle’ citrumelo (SC) rootstocks. The juices obtained from the combination of the ‘Rubi’ orange in both rootstocks stood out by their higher concentration of ascorbic acid (AA) and dehydroascorbic acid (DHAA). Overall, all SC-grafted scions showed higher AA and DHAA and some phenolic compound concentrations. In all combinations, phenolic compounds showed the highest concentrations in the juices at the time of fruit extraction and decreased during storage. Dark packaging provided higher bioactive compounds in juices stored for longer periods. These findings can contribute to the diversification of scion/rootstock cultivars in order to increase the variety of orchards by choosing the best combinations for pasteurized orange juice with higher nutritional value. Full article

Boswellia carterii, known as frankincense, is a fragrant medicinal plant. The essential oil from this plant is often used in traditional medicine or aromatherapy. Due to its positive properties, it has potential applications as an antimicrobial agent in medicine and the food industry. The aim of this study was to evaluate the antimicrobial, anti-insect, and antioxidant activities of frankincense essential oil (FEO). The composition of volatile compounds was determined by GC/MS, and the main components were found to be α-pinene (37.0%), α-limonene (19.8%), and p-cymene (6.3%). The antioxidant activity was evaluated with DPPH and ABTS methods with the resulting inhibition of 73.88 ± 0.35% of DPPH radical (6.27 ± 0.17 TEAC) and 97.09 ± 0.48% of ABTS radical cation (5.21 ± 0.07 TEAC). The antimicrobial activity was the strongest against Candida species with inhibition zones in the range of 38.00–44.00 mm and MIC 50 and MIC 90 values of 11.72 and 12.58 μL/mL, respectively. The inhibition activity of the vapor phase was the highest against G⁺ and G⁻ bacteria growing on a carrot with inhibition ranging from 65.14 to 93.67%. The anti-insect activity against O. lavaterae was determined as 100% at 100% concentration and 50% at 25% concentration. The degradation of biofilm was tested with MALDI-TOF MS, and changes in the protein profile were observed. Full article

This study was carried out to determine the effect of three commercial LEDs of different spectra with or without far red (FR) photons on the growth, morphology, and mineral content of two leafy vegetables under two temperatures (30 °C and 21 °C). The two leafy greens were ‘Cegolaine’ lettuce (Lactuca sativa) and ‘Petite Star’ pak choy (Brassica rapa subsp. Chinensis). In each temperature, there were three light spectra: red and blue LED, and white LED with or without FR. All spectra of lights were adjusted to a total photon flux density of 250 μmol m⁻² s⁻¹ at the top of the plant canopy. Results indicated that temperature treatment had a significant influence on most measured parameters. When temperature increased from 21 to 30 °C, lettuce shoot fresh and dry weights increased by 30% and 53%, respectively, while those of pak choy increased by approximately 22%. For both species, plants at high temperature had a larger leaf area but lower mineral content compared to those at low temperature. The spectrum treatment had a minor or no effect on the measured traits. In conclusion, the 5% FR did not impact the yield or biomass of either crop and the plant responses to spectra varied with temperature and species. The two temperatures resulted in significant differences in growth, morphology, and leaf mineral content in both species. Full article

Mango, banana, papaya, pineapple, and avocado are categorized as major tropical fruits grown for local consumption, export, and sources of income to the growers. These fruit crops are susceptible to infection by Fusarium in the field, and after harvest, it causes root rot, vascular wilt, stem rot, and fruit rot. Among the most common and economically important Fusarium species associated with diseases of major fruit are F. oxysporum and F. solani, which are prevalent in tropical regions. Other species include F. incarnatum, F. proliferatum, and F. verticilliodes. Most of these species have a wide host range and infect different parts of the plant. Due to the economic importance of these fruit crops, this review highlights the diseases and Fusarium species that infect fruit crops in the field as well as after harvest. Updated information on Fusarium species infecting major tropical fruit crops is important as disease management in the field and after harvest often relies on the causal pathogens. Moreover, major fruit crops are traded worldwide, and newly recorded species associated with these fruit crops are important for biosecurity purposes. Information on the diseases and causal pathogens may help to facilitate routine diagnosis and planning of suitable plant disease management methods. Full article

The sensory properties of fruit and vegetables are a result of taste and aroma caused by many volatile and nonvolatile compounds. The sum of organic acids (malic and citric acids) and soluble sugars (fructose and glucose), as well as their balanced combination and interaction, contributes to the characterization of the tomato flavour. The ratio of sugars and organic acids is the key to the sweetness and sourness of tomatoes. This study aimed to determine the sugar and organic acid content, as well as several physicochemical parameters, of eight tomato landraces from Croatia. All the parameters investigated differed between the tomato landraces. The PLS-DA analysis showed that the most important parameters in tomato landrace discriminatory character are malic acid, fructooligosaccharide content, citric acid, dry matter. The results obtained show a significant positive correlation between tomato dry matter and sugar content. At the same time, fructose and sucrose content is negatively correlated with the green to red hue of tomato peel, as well as positively with the blue to yellow hue, indicating that the sugar content increases with yellow color intensity. The blue to yellow hue of the peel color also positively correlates with citric acid content. Full article

Peach (Prunus persica) is one of the representative climacteric fruits susceptible to environmental stresses, including microbial contamination. This article analyzed major findings from the literature on pre- and post-harvest technologies for maintaining the quality of peach fruit to figure out the strengths and limitations of each treatment strategy. The key implication from studies of pre-harvest agents directly applied to the fruit surface or supplemented as fertilizer was the application of a mixture regarding substances with diverse working mechanisms to prevent excessive use of the agent. The common objectives of previous research on pre-harvest treatments were not only the improvement in the quality of harvested fruit but also the storability during long-term refrigeration due to the short lifespan of peaches. In the case of post-harvest treatments, the efficacy was considerably affected by various determinant factors (e.g., a cultivar of fruit, the sort of technologies, and storage environments), and thus operating conditions optimized for peach fruit were described in this article. Whereas, although the combined treatment of technologies categorized into principles (physical, chemical, and biological approaches) has been adopted to achieve the synergistic effect, undesirable antagonistic effects (i.e., the inhibition of efficacies expectable from singular treatments) were also reported to highlight the importance for exploring adequate treatment conditions. Full article

To develop a way to mass-produce sweet potatoes (Ipomoea batatas (L.) Lam.) as an energy crop to replace fossil fuels, the effects of using a sewage supply as a fertilizer and heat source were investigated. When 25 pots planted with sweet potato vine seedlings were arranged in three layers and cultivated for 160 days from June to November by supplying treated sewage to the root zone, the yield of tuberous roots reached 19.5 kg m⁻² due to the massive growth of leaves. In addition, when sweet potato seedlings were replanted in December and treated sewage was supplied to maintain the irrigation water temperature above 15 °C even in winter, overwintering cultivation was successful and 8.4 kg m⁻² of tuberous roots were harvested in July. As a result, the annual production rate for 12 months increased to 25.3 kg m⁻², about 10 times the national average of 2.4 kg m⁻² for open-field cultivation. The results far exceed previously reported maximum production of resource crops, such as sugarcane and eucalyptus, suggesting that the mass production of sweet potatoes by supplying treated sewage could provide an alternative to fossil fuels on a large scale. Full article

The forest–medicinal plant management system has benefited the commercial production of Amomum villosum. However, little is known about the influence of different forestlands on the cultivation of A. villosum. The present study investigated the potential differences in the A. villosum yield and quality parameters, rhizosphere soil properties, and rhizosphere soil microbiota between a rubber plantation (RP) and a natural secondary forest (NSF). No significant differences in yield or rhizosphere soil properties of A. villosum were observed between RP and NSF, although most of the A. villosum yield parameters, the rhizosphere soil physicochemical properties, and soil enzyme activities were higher in NSF than in RP. Furthermore, the 38 volatile components had significantly higher relative abundances in NSF than in RP. Furthermore, the alpha diversity indices for the microbiota communities in the A. villosum rhizosphere soil indicated that the richness of the bacterial and fungal communities was significantly higher in NSF than in RP. These findings suggest that NSF conditions may be more appropriate than RP conditions for growing A. villosum. The data generated in this study may be useful for increasing the production of high-quality A. villosum via the exploitation of natural environments. Full article

Almond cultivation in the Mediterranean area has undergone important changes leading to the current trend of intensification. In this scenario, low-vigor rootstocks have recently been developed, such as the ‘Rootpac^®’ series, but knowledge about the rootstock’s influence on adaptation to high-density planting systems is very scarce. The objective of this work was to assess the morphological and physiological response of four almond cultivars grafted on ‘Rootpac-20’. To this end, one-year-old almond plants (Prunus dulcis (Mill) D. A. Webb.) cv ‘Penta’ (P), ‘Guara’ (G), ‘Vialfas’ (V) and ‘Soleta’ (S) were grown in pots, irrigated at field capacity (from June to September). Plant height and trunk diameter were measured periodically, and the water use efficiency of production was determined at the end of the trial. Evapotranspiration was measured throughout the experiment. The trunk diameter was greater in S and G at the end of the trial. Similarly, the tallest plants were G while the shortest ones were P. In general, G and S had a higher water use efficiency than V and P. ‘Soleta’ grafted on ‘Rootpac-20’ had higher evapotranspiration values (+25%), which is an important issue when selecting plant material, especially in the case of limited water availability for irrigation. Full article

MicroRNAs (miRNAs) are endogenous noncoding small RNAs containing 21–24 nucleotides (nt) that regulate gene expression precisely and efficiently at the posttranscriptional level through the negative regulation of target messenger RNA (mRNA) expression, such as translational inhibition or degradation. Likewise, as a controlling element, miRNA itself is regulated by a variety of factors when performing its basic purposes, such as SNP detection, miRNA purging, methylation, and the circadian clock in model crops. In current years, miRNA-mediated controls have been intensely investigated in horticultural plants, leading to the discovery of numerous novel mechanisms that exhibit significantly greater mechanistic complexity and distinctive regulatory properties than those explored in model species. In fruit crops, miRNAs play a crucial role corresponding to various biological, metabolic functions and environmental challenges, including growth, expansion, response to biotic and abiotic stress, signaling of growth hormones, and the regulation of secondary product metabolism. In this study, we appraisal the current improvement of small regulatory RNA research in fruit crops, emphasizing miRNA mechanisms and their correlation with key trait rule. Considering that miRNAs engaged in the regulation of all aspects of fruit tree life activities, we focus here on their biosynthesis, target genes, function and regulatory network, as well as the mechanistic connection among them, to provide a theoretic base and breakthrough for upcoming exploration on miRNAs in fruit plants. Full article

Aquaponics is a promising cultivation technique for combined production of crops and fish, on the condition of tackling certain nutrients deficiencies. The aim of the present study was to examine the limitations imposed by the system on spinach (Spinacia oleracea) growth and functional performance and to identify the minimum nutrient supplementation for their optimization. Spinach was co-cultivated with red tilapia under three treatments; iron (Fe) and iron with potassium (Fe+K) enrichment was compared with the no-external input control. During a 45-day experiment, the photosynthetic performance, photosynthetic machinery efficiency, total chlorophylls content, and leaf reflectance were monitored, along with leaf nutritional state, antioxidant activity, and growth responses of fish and crops. Control plants showed symptoms of Fe deficiency, extensive chlorosis, stunted growth, and functional impairment already from day 10. The latter consisted of a coordinated down-regulation of photochemistry, carboxylation, and light-use efficiency. Fe-treated plants exhibited similar growth and functional performance with Fe+K-treated plants but outperformed them in chlorophyll content, photosynthetic rates, and photochemical efficiency, mainly due to higher quantum yield of electron transport. Fish growth remained unaffected. Fe-deficiency was identified as the major bottleneck for spinach cultivation in closed-loop aquaponics, and our results demonstrate that only Fe supplementation may sufficiently improve spinach function and yield. Full article

Philodendron bipinnatifidum Schott ex Endl. is a popular ornamental plant that is normally propagated by tissue culture methods. However, the growth and acclimatization of micropropagated plants are tarrying processes. Therefore, in the present study we examined the effect of arbuscular mycorrhizal fungi (AMF) Gigaspora albida and G. marginata on the success in the establishment, growth, and development of P. bipinnatifidum plantlets during the acclimatization phase. AMF plants had significantly more leaves (10.67 per plant), leaf area (75.63 cm²), plant height (14.17 cm), shoot fresh weight (3.30 g) and shoot dry weight (0.31 g), according to an analysis of growth characteristics. In comparison, non-AMF plants had lower values for these metrics. In addition, AMF plants had significantly longer main roots (23 cm), total length roots per plantlet (485.73 cm), average root diameter (4.58 mm) per plantlet, number of root tips (236) per plant, total root surface area (697.76 cm²), total root volume (79.98 cm³), roots fresh weight (1.51 g), roots dry weight (0.16 g) than non-AMF plants. AMF-treated plants showed better performance in leaf gas exchange, chlorophyll, and carotenoid content. These results emphasize the need for mycorrhization of micropropagated plants to promote vegetative growth, especially during the acclimatization stage. Full article

Apple is a major fruit crop grown worldwide and provides humans with an essential diet and health benefits. One of the health benefits is related to the accumulation of fruit anthocyanin, which also provides fruit with an attractive red colour. It is known that an MdMYB10 allele containing a transposable element (TE) insertion in its promoter (termed Red-TE allele) underlies anthocyanin accumulation and red colouration in the fruit skin of cultivated apples. However, the distribution of this Red-TE allele in wider Malus germplasm accessions is not clear. In this study, we showed that MdMYB10 RNA in fruit skin was specifically expressed from the Red-TE allele by using allele-specific expression analysis of transcriptome data. Apple cultivars and hybrids with homozygous Red-TE alleles showed stronger red colour than those with heterozygous alleles after analysing 65 cultivars and 337 hybrids. Furthermore, both hetero- and homozygous plants growing in the same high-temperature conditions had different colourations. However, the Red-TE allele was not detected in 16 wild apple accessions showing red skin, indicating that the red skin colour of these wild apples was not conferred by the Red-TE allele. These findings provide guidance for selecting cultivars able to develop consistent red colouration under high growth temperature conditions and open the opportunity for identifying novel genetic variants underpinning fruit red colouration in wild apple species. Full article

Thinning is an important routine for apple growers to manage crop load and improve fruit quality, which can be accomplished through manual, chemical, or mechanical manipulation of flowers and fruitlets. Traditionally, blossom thinning relies on human experts’ visual evaluation of the flower load, a leading indicator of crop load, which can be imprecise and prone to errors. This study aimed to develop an apple blossom density mapping algorithm utilizing point clouds reconstructed through unmanned aerial vehicle (UAV)-based red-green-blue (RGB) imagery and photogrammetry. The algorithm was based on grid average downsampling and white color thresholding, and it was able to generate top-view blossom density maps of user-defined tree height regions. A preliminary field experiment was carried out to evaluate the algorithm’s accuracy using manual blossom counts of apple tree row sections as ground truths, and a coefficient of determination (R²) of 0.85, a root mean square error (RMSE) of 1307, and a normalized RMSE (NRMSE) of 9.02% were achieved. The algorithm was utilized to monitor the blooming of the apple tree rows and was demonstrated to effectively show blossom density variations between different tree rows and dates. The study results suggested the potential of UAVs as a convenient tool to assist precise blossom thinning in apple orchards, while future research should further investigate the reliability of photogrammetry techniques under different image qualities and flight settings as well as the influence of blossom distribution on algorithm accuracy. Full article

Brassica vegetables are very important to human beings. Self-incompatibility (SI) is a common phenomenon in Brassica. Breeding by SI lines is an important way to utilize heterosis of Brassica vegetables. It is believed that the SI inheritance in Brassica species is controlled by three linkage genes on the S-locus, including SRK (S-locus receptor kinase), SCR (S-locus cystine-rich protein)/SP11 (S-locus protein 11), and SLG (S-locus glycoprotein). SRK is the female determinant and SCR/SP11 is the pollen S gene. The expression of SLG is necessary for SRK, and it enhances the SRK-mediated SI reaction. In addition to these three S-locus genes, some other functional molecules also have significant regulatory effects on SI, such as ARC1 (arm repeat containing 1), MLPK (M-locus protein kinase), Exo70A1 (exocyst compounds), THLl/THL2 (thioredoxin H-like), MOD (aquaporin), SLR (S-locus-related glycoprotein), BPCI (pollen calcium-binding protein I), etc. SI is also associated with the dominant/recessive relationship between S alleles. Here, the genetic elements and molecular mechanisms of SI, mainly in Brassica vegetables, are reviewed. Full article

In southern Europe, irrigation is the major water user and thus, development of operational tools that support decisions aiming to improve irrigation management, is of great importance. In this study, a web-based participatory decision support system for irrigation management (DSS), based on the principles of UN FAO’s paper 56, without requirement for any special monitoring hardware to be installed in each field, is evaluated for the case of a commercial wine grapevine (Vitis vinifera ‘Vertzami’) located at Epirus (northwest Greece), for two successive years (2021 and 2022). The soil moisture time series that were generated by the DSS’s model were compared to those measured by soil moisture sensors. The Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) ranged between 2.98–3.22% and 3.63–4.06%, respectively, under various irrigation practices and goals. Irrigation resulted very high yields and Crop Water Productivity (WPC) was 20–44% improved when following the DSS’s recommendations. The results also confirm potential pitfalls of sensor-based soil moisture monitoring and rainfall estimations using mathematical models. Finally, the value of water meters as practical sensors, which could support efficient irrigation management, is underlined. In every case, mindful application of decision support systems that require minimum or no hardware to be installed in each field, could extensively support growers and agronomic consultants to test, document and disseminate good practices and calculate environmental indices. Full article

This study investigated the optimization of shading and organic fertilizer applications on vegetable fern growth and yield quality in order to develop guidelines for farmers interested in sustainable vegetable fern production. The experiment was conducted in a split-plot design in RCBD with four replications. There were three main plots; no shading, 75% shading, and 96% shading. The five sub-plots consisted of no fertilizer application (control), chemical fertilizer at a rate of 92.80 kg N ha⁻¹, and cow manure at rates of 92.80, 185.60, and 278.40 kg N ha⁻¹. A comparison between different shading and fertilizer treatments, combined, demonstrated that 75% shading with the application of cow manure at the rate of 185.60 kg N ha⁻¹ was the most appropriate management for vegetable fern production, with the highest marketable yield recorded (1128.54 kg ha⁻¹ month⁻¹) and a 10-fold yield increase compared to the control (no shading and no fertilizer). This treatment also resulted in good yield quality (crunchy and tender), high concentrations of chlorophyll and vitamin C, and a safe amount of nitrate accumulation for consumers. Full article

Rind pattern is one of the most important appearance qualities of watermelon, and the mining of different genes controlling rind pattern can enrich the variety of consumer choices. In this study, a unique intermittent rind stripe was identified in the inbred watermelon line WT20. The WT20 was crossed with a green stripe inbred line, WCZ, to construct F₂ and BC₁ segregating populations and to analyze the genetic characterization of watermelon stripe. Genetic analysis showed that the intermittent stripe was a qualitative trait and controlled by a single dominant gene, ClIS. Fine mapping based on linkage analysis showed that the ClIS gene was located on the 160 Kb regions between 25.92 Mb and 26.08 Mb on watermelon chromosome 6. Furthermore, another inbred watermelon line with intermittent stripe, FG, was re-sequenced and aligned on the region of 160 Kb. Interestingly, only two SNP variants (T/C, A/T) were present in both WT20 and FG inbred lines at the same time. The two SNPs are located in 25,961,768 bp (T/C) and 25,961,773 bp (A/T) of watermelon chromosome 6, which is located in the promoter region of Cla019202. We speculate that Cla019202 is the candidate gene of ClIS which controls the intermittent stripe in watermelon. In a previous study, the candidate gene ClGS was proved to control dark green stripe in watermelon. According to the verification of the two genes ClIS and ClGS in 75 watermelon germplasm resources, we further speculate that the ClGS gene may regulate the color of watermelon stripe, while the ClIS gene regulates the continuity of watermelon stripe. The study provides a good entry point for studying the formation of watermelon rind patterns, as well as providing foundation insights into the breeding of special appearance quality in watermelon. Full article

Field pea (Pisum sativum L.) is a highly nutritious winter-season pulse crop. It is used as food, feed, and fodder and offers nutritional security to low-income people in developing countries. Different graphical approaches like Principal Component Analysis (PCA) and Genotype + Genotype × Environment (GGE) biplots were used along with the conventional line × tester to identify efficient parents, combining ability effects and distinct heterotic groups in field pea (Pisum sativum L.). The study used a line tester design (9 × 3) for seed yield and its associated traits. In the conventional analysis, lines Aman and HFP 715 and the tester GP02/1108, as well as crosses HFP 715 × GP02/1108, Aman × GP02/1108, and Pant P-243 × HFP 1426 showed the best GCA (General Combining Ability) and SCA (Specific Combining Ability) effects, respectively, for seed yield and its attributes. The ^σ2SCA > ^σ2GCA, and ^σ2D > ^σ2A in almost all the traits indicated control of non-additive gene effects. High manifestations of heterobeltiosis for seed yield were evidenced by the superiority of 24 out of 27 crosses over the better parent. The highest significant heterobeltiosis was observed in the cross HFP 715 × GP02/1108, followed by IPF 14-16 × GP02/1108, IPF 14-16 × HFP 1426, DDR-23 × HFP 1426, DDR-23 × GP02/1108, and Aman × GP02/1108 for yield and its attributes. The biplot techniques were used to analyze data and compare their results with conventional line × tester analysis. Overall, graphical analysis results were very similar to those of traditional analysis. Consequently, it can surely be assumed that these methods could be helpful in presenting data from field pea breeding experiments carried out with line × tester design. Full article

Horticultural crops suffer from bacterial, fungal, and oomycete pathogens. Effectors are one of the main weapons deployed by those pathogens, especially in the early stages of infection. Pathogens secrete effectors with diverse functions to avoid recognition by plants, inhibit or manipulate plant immunity, and induce programmed cell death. Most identified effectors are proteinaceous, such as the well-studied type-III secretion system effectors (T3SEs) in bacteria, RXLR and CRN (crinkling and necrosis) motif effectors in oomycetes, and LysM (lysin motifs) domain effectors in fungi. In addition, some non-proteinaceous effectors such as toxins and sRNA also play crucial roles in infection. To cope with effectors, plants have evolved specific mechanisms to recognize them and activate effector-triggered immunity (ETI). This review summarizes the functions and mechanisms of action of typical proteinaceous and non-proteinaceous effectors secreted by important horticultural crop pathogens. The defense responses of plant hosts are also briefly introduced. Moreover, potential application of effector biology in disease management and the breeding of resistant varieties is discussed. Full article

Low nitrogen stress severely impedes crop growth and productivity. There has been substantial research on root adaptation to low nitrogen conditions in many plant species. However, the mechanism underlying the morphological response of the strawberry (Fragaria × ananassa Duch.) root to low-NO₃⁻ or low-NH₄⁺ stress remains poorly understood. Strawberry plants were hydroponically cultivated under 1 mM NO₃⁻, 1 mM NH₄⁺, and control (15 mM NO₃⁻) conditions to assess the physiological responses of their roots to low nitrogen stress. As a result, low nitrogen stresses increased the fresh weight of root, lateral root density, and root surface area, as well as enhanced the accumulation of indole-3-acetic acid and jasmonic acid while significantly reducing salicylic acid in the roots. Correspondingly, low nitrogen stresses increased PM H⁺-ATPase activity. Low-NO₃⁻ stress enhanced the activities of nitrate reductase and glutamine synthetase, whereas low-NH₄⁺ treatment led to higher glutamine synthetase and glutamate synthase activities. Collectively, the present results demonstrate that low nitrogen stresses enhance nitrogen uptake of strawberry roots by regulating hormones (indole-3-acetic acid, jasmonic acid, and salicylic acid) and thereby mediating PM H⁺-ATPase activity, while promoting nitrogen metabolism by upregulating the activities of nitrate reductase, glutamine synthetase, and glutamate synthase. In conclusion, low nitrogen conditions may facilitate more efficient acquisition of available N from the soil by strawberry root system. Full article

Plant G protein γ subunits have multiple functions in growth and development processes and in abiotic stress responses. Few functions of Gγ in horticultural crops have been revealed thus far. In this study, the potential function of CsGG3.1-2, one of the two alternative splice variants of Gγ gene CsGG3.1 in cucumber (Cucumis sativus L.), was investigated using transgenic plants overexpressing antisense CsGG3.1-2 under the control of the 35S promoter. The tolerance to chilling stress in transgenic plants was significantly decreased. Cold stress-related physiological parameters and the expression of CBFs and their downstream target genes were then measured. Compared with WT, the maximum efficiency of photosystem II (Fv/Fm), antioxidative enzymes activities, soluble protein, and proline accumulation decreased significantly in transgenic plants treated with cold stress, whereas the malonaldehyde (MDA) content increased. However, the overexpression of antisense CsGG3.1-2 did not affect the induction of cold-inducible genes. Quantitative real-time PCR (qPCR) analysis showed the increased expression of CBF genes and their downstream target genes in transgenic plants, suggesting that CsGG3.1-2 affects cold responses via CBF-independent pathways in cucumber. At the same time, the sucrose and fructose contents decreased in transgenic plants under both normal and cold conditions. These findings suggest that soluble sugar deficiency is associated with chilling sensitivity in transgenic plants, and CsGG3.1-2 may have a role in regulating carbohydrate metabolism in cucumber. Full article

Viticulture around the world is currently affected by climate change, which is causing an increasing scarcity of water resources necessary for the maintenance of vineyards. Despite the drought hardiness of grapevine (Vitis vinifera L.), this threat seriously compromises its cultivation in the near future, particularly in wine-growing areas with a semi-arid climate. Identifying varieties capable of producing suitable yields and good-quality grapes under drought conditions is integral to ensuring the sustainability of the wine sector. This study focuses on vines from both minority and widely grown varieties, which were supplied only with the water intended to ensure their survival. The carbon and oxygen isotope ratios, yield, and quality parameters were evaluated on the vines and musts during the period of 2018–2020. The results revealed that not all varieties responded equally well to drought. Albillo Real, Coloraillo, Macabeo, and Verdejo adapted well to drought conditions, simultaneously maintaining high yields and must quality. By contrast, Pedro Ximénez can be considered poorly adapted. This variety was the one that produced the lowest yield and had low acidity levels in the must. Full article

Bacterial canker of tomato is a systemic disease caused by Clavibacter michiganensis (Cm), which poses a grave threat to tomato production worldwide. Towards the identification of genes underlying resistance to Cm infection, the transcriptome of the resistant inbred backcross line IBL2353 carrying the Rcm2.0 locus derived from Solanum habrochaites LA407 and the susceptible Solanum lycopersicum line Ohio88119 was comparatively analyzed after Cm inoculation, and the analysis focused on the genes with different expression patterns between resistant and susceptible lines. Gene ontology (GO) analysis revealed that top terms of differentially expressed genes comprised ubiquitin protein ligases, transcription factors, and receptor kinases. Then we screened out some genes which are potentially associated with the defense response against Cm infection in IBL2353 including the wall-associated receptor kinase-like 20 (WAKL20), and virus-induced gene silencing showed it contributes resistance to Cm infection. In addition to Cm-induced genes related to resistance, the expression of eight homologs from six susceptibility (S) gene families was analyzed. These putative resistance and susceptibility genes are valuable resources for molecular resistance breeding and contribute to the development of new control methods in tomato. Full article

The effect of pre-application of structural auxin analogues TA-12 (1-[2-chloroethoxycarbonyl-methyl]-4-naphthalenesulfonic acid calcium salt) and TA-14 (1-[2-dimethylaminoethoxicarbonylmethyl] naphthalenechlormethylate) on biochemical parameters of pea (Pisum sativum L. cv. Jablo) plants subjected to low temperature (LT, −1 °C, for 24h) was studied. For the first time the effects of these auxin analogues, applied with or without LT were investigated on the endogenous polyamine (PA) content. The LT treatment increased free and bound putrescine (Put) and spermine (Spm), conjugated and bound spermidine (Spd), accompanied by a decrease in conjugated Put and Spm, and free Spd. Stress biomarkers hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) as well as proline were augmented by LT treatment. The TAs application decreased conjugated polyamines (Put, Spm and Spd), free Spd, H₂O₂ and MDA but increased bound Spm and proline in pea plants. The application of TAs before LT lessened the alterations in PAs (mainly in free and bound fractions) and stress biomarkers content caused by LT, and enhanced conjugated Spd and phenolics, which contributed to increased plant cold tolerance. Full article

Tomato leaf curl New Delhi virus (ToLCNDV, family Geminiviridae, genus Begomovirus) is a whitefly-transmitted virus that causes widespread damage in Cucurbitaceae and Solaneceae crops worldwide. The Spanish strain, ToLCNDV-ES, affects mainly cucurbit crops and has spread through the Mediterranean basin since its first detection in 2013 in the south of Spain. The control of the virus has been based on the adoption of measures to control the vector, which have not been sufficient to reduce production losses. Therefore, the identification of key genes for ToLCNDV resistance is essential for the development of resistant plants. Regarding genetic control of resistance in cucurbit crops, one major locus on chromosome 11 and two additional regions in chromosomes 12 and 2 of C. melo linked to ToLCNDV resistance have been described recently. Concerning C. moschata, a major QTL was also identified on chromosome 8 that resulted in synteny with a QTL on chromosome 11 of C. melo. In this work, we investigated the molecular basis of ToLCNDV resistance in contrasting accessions of C. melo and C. moschata by transcriptional characterization of 10 different candidate genes controlling host factors related to proviral or antiviral mechanisms. Two proviral factor genes, ARP4 in C. melo and SYTA in C. moschata, showed clear differences in expression levels when the susceptible and resistant accessions were compared. The knowledge of proviral factors associated with resistance could be used to screen an active mutagenesis TILLING platform. This is the case of C. pepo, in which no ToLCNDV resistance has been described to date. The relationship between the regulation of the genes ARP4 and SYTA, as well as the genome position of the described loci related to ToLCNDV resistance, is also discussed. Full article

Mentha arvensis L. and Mentha × piperita L. are herbal plants belonging to the Lamiaceae family and are widely cultivated for their essential oils and culinary uses. These herbs are commercially valuable mints used in the preparation of herbal formulations, cosmetics, pharmaceuticals, and in food industries. Due to the presence of potential secondary metabolites, mints were employed to treat various disorders since ancient times in traditional medicines. The extracts of M. arvensis and M. × piperita can improve the function of digestive system, central nervous system and respiratory system of the human body. Majority of the health benefits of these herbs are attributed by the essential oil components. In addition, the administration of M. arvensis and M. × piperita under various pathological conditions studied in vitro and in vivo facilitated the recovery of detrimental ailments. Due to the increasing demand for natural product-based medicines, research is focused on the utilization of phytochemicals to treat various ailments. In order to provide a comprehensive overview of health benefits of M. arvensis and M. × piperita, the present endeavor deals with the antioxidant property, anti-inflammatory property, anti-microbial, and anti-cancer activities of both species. However, a deeper knowledge on the specific metabolites of M. arvensis and M. × piperita and their mode of action against different disease targets will accelerate the discovery of novel natural drugs with less side effects and higher efficiency. Full article

The nutritional quality and biomass of various sprouts can be enhanced by Zn and red-blue light, especially the Brassica sprouts. However, the combined effects of this two on sprouts are rarely reported. In this study, different Zn concentrations (0, 1.74, 3.48, 10.43 and 17.39 mM) were combined with two ratios of red-blue light-emitting diodes (LEDs) (R: B = 1:2, 1R2B; R: B = 2:1, 2R1B, at 70 μmol m⁻² s⁻¹ PPFD, 14 h/10 h, light/dark) to investigate their mutual effects on the growth, mineral elements, and nutritional quality in flowering Chinese cabbage sprouts (FCCS). Fresh weight, dry weight, contents of organic Zn, soluble sugar, vitamin C, total flavonoids, total polyphenol, FRAP (ferric ion-reducing antioxidant power) and DPPH (radical inhibition percentage of 1,1-diphenyl-2-picrylhydrazyl) were significantly increased by Zn supplement (10.43 and 17.39 mM) and 2R1B, while hypocotyl length and moisture content were decreased remarkably by Zn supplement. Total glucosinolates contents in the sprouts increased dramatically under 2R1B compared with 1R2B, while photosynthetic pigments contents decreased. Heat map and principal component analysis showed that 2R1B + 17.39 mM Zn was the optimal treatment for the accumulation of biomass and health-promoting compound in FCCS, suggesting that a suitable combination of light quality and Zn supplement might be beneficial to zinc-biofortified FCCS production. Full article

This study presents the effects of exogenous melatonin application at different concentrations (50, 100, and 200 μM) on the morphological, physiological, and antioxidant defense systems of the buttercup plant under salinity stress (4.5 and 5.5 dS·m⁻¹ EC). Expectedly, the salinity stress negatively affected the plant growth parameters, cell membrane stability, and POX enzyme activity of R. asiaticus compared to non-stressed plants. However, in a dose-dependent manner, exogenous melatonin foliar application decreased the salt stress-induced symptoms of retarded vegetative growth, physiological characteristics, and oxidative stress level. The results obtained, revealed the significant effectiveness of exogenous melatonin treatment at 200 μM concentration under salt stress conditions by enhancing the plant growth traits such as chlorophyll and carotenoids content, relative water content, proline content, peroxidase enzyme activity (POD), and by the decreased electrolyte leakage rate, and Na⁺ content, as well as delaying the emergence of flower buds under salinity stress. The salt tolerance index percentages (STI%) for all estimated characters are also calculated for all studied parameters. This study uncovered the beneficial effect of melatonin in reducing salt stress symptoms that can be used to reduce the salinity effect in ranunculus plant production. Full article

Fresh vegetables and fruits have always been the mainstays of good nutrition as providers of fiber, beneficial phytochemicals (such as vitamins and phenolic compounds), and minerals. Today and in the future, biofortification is a promising strategy to increase the concentration of these compounds. Considering the importance of minerals in human health, the enrichment of fresh produce for consumption has been considered through specific agronomic approaches. This review discusses, in detail, the latest findings on vegetable agronomic biofortification, aimed at increasing the concentration of crucial minerals, such as iron (Fe), zinc (Zn), iodine (I), selenium (Se), molybdenum (Mo), and silicon (Si), in edible portions, focusing on the direct and indirect effects of this strategy. Although agronomic biofortification is considered a feasible technique, the approach is complex due to the many interactions between the microelement bioavailability for both plants and consumers. Therefore, the effects of biofortification on human health and the influence of beneficial and antinutritional compounds were discussed in detail to analyze the advantages and disadvantages of this practice. Full article

The herbaceous peony (Paeonia lactiflora Pall.), a perennial herbaceous flower, can grows continuously for approximately 10 years. However, a replanting problem can occur during division propagation which reduces the land use rate and restricts the development of the herbaceous peony industry. We investigated microbial community changes and soil chemical properties in herbaceous peony soils during different growing and replanting years. The results indicated that the flowering rate, plant height, stem diameter, and leaf area of replanted herbaceous peony were lower, and decreased gradually with increasing replanting years. Compared with the soil after replanting herbaceous peony for one year, soil pH, nutrient contents (AN, AP, AK, and OM), enzyme activities (Inv, Ure, Pho, and Cat), diversity and richness of fungal and bacterial communities decreased after replanting for five years. Long-term replanting increased the relative abundance of harmful soil microorganisms (e.g., Gibberella), and reduced that of beneficial microorganisms (e.g., Bacillus). Overall, after the long-term replanting of herbaceous peony, the soil environment deteriorated, and the soil microbial community structure changed, resulting in the imbalance of soil microecology, damaging the normal growth of herbaceous peony. Full article

Controlled environment agriculture (CEA) operations must increase resource-use efficiency, yield, and phytonutrient concentrations to remain competitive. Carotenoids are phytonutrients of interest due to their purported health promoting effects. Their content is impacted by environmental controls, including lighting. Light-use efficiency increases with greater planting density, which is highest during seedling production. This creates the opportunity to raise light intensity during seedling production to improve growth characteristics and phytonutrient concentrations at harvest. Therefore, the objective of this research was to quantify the extent to which light intensity influences carotenoid accumulation in green butterhead lettuce seedlings, and if differences remain at harvest. Lettuce ‘Rex’ (Lactuca sativa L.) seedlings were grown under fluorescent lighting with intensities of 60, 100, 200, 400, or 600 µmol·m⁻²·s⁻¹ with a 24-h photoperiod. After 14 days, seedlings were transplanted into raft hydroponic systems in a common greenhouse environment and grown for 21 days. At transplant and final harvest, tissue samples were collected and stored at −80 °C for phytonutrient analysis. Carotenoids, β-carotene, lutein, neoxanthin, zeaxanthin, and violaxanthin, and chlorophylls a and b were quantified using high-performance liquid chromatography (HPLC). We observed a 475% fresh mass enhancement in seedlings grown under 400 versus 60 µmol·m⁻²·s⁻¹, with a 174% improvement persisting to final harvest. Higher seedling light intensities also generally increased leaf numbers in seedlings and at final harvest, as well as seedling carotenoid concentrations. Final harvest carotenoid concentrations generally decreased with increasing light intensity. Thus, producers should be cognizant that seedling light intensity strongly influences seedling and finished production yield, morphology, and carotenoid content. Full article

Moringa oleifera is a relatively well-studied ethnobotanical species, but information is limited regarding its stem anatomy and the production potential of phytochemicals from bark tissue. Knowing that variation exists in the production of chemical defenses by plants with growing conditions and with developmental stages, M. oleifera was grown under controlled conditions to characterize stem tissues and to determine if stem bark contained the correct phytochemical compounds to be of value in medicinal treatments. We used microscopy to characterize the stem anatomy of M. oleifera and analyzed stem bark extracts using FTIR and GC to identify 4-(α-L-rhamnosyloxy)-benzyl isothiocyanate (moringin) and benzylamine (moringine) in tissue. We found the stems to be in transition between juvenile and mature stages of development at 4 months old under the growth conditions used. In 7-month-old stems, we found the presence of moringin in all bark samples and did not find any moringine. These results indicate that M. oleifera bark of 7-month-old trees grown in greenhouse conditions may be valuable for drug development. Full article

Postharvest ultraviolet B (UV-B) radiation has been used to control pathogen incidence on fresh produce, but little attention has been paid to preharvest UV-B effect on strawberry fruit quality and storage. In this study, strawberry (Fragaria × ananassa Duch. cv Albion) plants grown in greenhouse were irradiated with UV-B lamps with an intensity of 0.7362 J/s m² for 1 and 2 h every day from 5–7 pm after flowering. Fruits were harvested at red stage for quality evaluation. The results indicated that the preharvest UV-B-treated fruits had lighter color (increased L*) than the control. Total soluble solids (TSS), total phenolics content (TPS) and total anthocyanin content (TAC) of UV-B-treated fruits were higher than for the control fruits. There were no significant differences in any of the quality traits between UV-B one-hour and two-hour treatments. We further evaluated the fruit quality when stored at 5 °C on day 7 and day 14. Compared to untreated control, UV-B-treated fruits retarded decrease in L*, TSS, TPS, TAC and firmness, and reduced fruit decay. Examination of expression of genes related to UV-B signaling indicated that HY5 was the major component of UV-B signaling during the green and white stages. However, anthocyanin genes were highly responsive to UV-B treatment during the red stage. Our results suggest that utilization of a low dose of UV-B radiation during the growth stage can improve strawberry fruit quality, and extend shelf life. This research facilitates the utilization of preharvest UV-B treatment for improving fruit quality in controlled environment agriculture. Full article

Soilless cultivation is one of the best examples of the sustainable intensification concept due to the high use efficiency of its inputs. Managing the nutrient solution through a closed cycle system represents a crucial objective to be pursued, but the recovery of the nutrient solution requires chemical correction and sanitization. The application of non-thermal plasma (NTP) in agriculture promotes the safety of the nutrient solution, decreasing the use of chemicals. The aim of this study was to evaluate the effects of cold plasma on the nutrient depletion, yield, and qualitative traits of lettuce. A closed soilless system (nutrient film technique) was used to compare different NTP treatments: control, low ionization (LI), and high ionization (HI) in two successive lettuce cycles. No significant differences within the nutrient depletion trends were observed. The treated lettuce’s yield was 12% higher than that of the control, characterized by a higher total soluble solid content and a significantly higher electrical conductivity and titratable acidity than the control. The ion content was higher in HI plants, as were the contents of nitrogen, phosphorous, and potassium. In HI plants, the leaf pigments were higher, but no significant changes were observed for the antioxidant content. Cold plasma is a promising strategy that brings benefits to the crop. Full article

In the current study, the effect of boiled chicken manure (BCM) doses by fertigation, bokashi, and mineral fertilization on the agronomic variables, bioactive compounds, and nitrate levels of two cultivars of lettuce (romaine and frisée types) and one cultivar of radicchio chicory was studied. Overall, higher agronomic variable values were found for the leafy plants in bokashi-fertilized plants. The BCM 5, 7.5, and 10% fertilization, in general, increased these variables in an apparent increasing trend. For chicory, bokashi presented higher means in comparison with BCM for TB, CB, and CI. For frisée lettuce, bokashi had the highest values for TB, CB, and PH. For romaine, bokashi presented the highest means for all the variables, except for PD. For bioactive compounds, each plant species responded differently when varying the fertilization source. For the nitrate content, higher values were observed in the bokashi and mineral treatments. Full article

Alternative splicing (AS) is an important way to generate notable regulatory and proteomic complexity in eukaryotes. However, accurate full-length splicing isoform discovery by second-generation sequencing (SGS) technologies is beset with the precise assembly of multiple isoforms from the same gene loci. In recent years, third-generation sequencing (TGS) technologies have been adopted to gain insight into different aspects of transcriptome complexity, such as complete sequences of mRNA, alternative splicing, fusion transcript, and alternative polyadenylation (APA). Here, we combined PacBio Iso-Seq and Illumina RNA-Seq technologies to decipher the full-length transcriptome of peach. In total, 40,477 nonredundant high-quality consensus transcript sequences were obtained from equally pooled libraries from 10 samples of 6 organs, including leaf, shoot, flower, fruit peel, fruit mesocarp, and fruit stone, of which 18,274 isoforms were novel isoforms of known genes and 546 isoforms were novel gene transcripts. We also discovered 148 fusion transcripts, 15,434 AS events, 508 potential lncRNAs, and 4368 genes with APA events. Of these AS events, the most abundant (62.48%) AS type was intron retention (IR). Moreover, the expression levels of different isoforms identified in this study were quantitatively evaluated, and highly tissue- or development stage-specific expression patterns were observed. The novel transcript isoforms and new characteristics of the peach transcriptome revealed by this study will facilitate the annotation of the peach genome and lay the foundations for functional research in the future. Full article

Hyposoter didymator (Thunberg) (Hymenoptera: Ichneumonidae) and baculovirus (BV) might be used jointly to provide effective control of the Spodoptera genus. The literature has mostly covered the safe compatibility between natural enemies and BV-based insecticides, but research on the potential dispersal of BV by natural enemies is lacking. Thus, the goal of this manuscript was to ascertain if H. didymator was able to disperse the broad host range of Autographa californica nucleopolyhedrovirus (AcMNPV) to Spodoptera littoralis and Spodoptera exigua in choice and non-choice conditions and whether the preference of the parasitoid by one of these noctuids could mediate this dispersion. It was previously needed to improve the rearing of the parasitoid in the laboratory, concerning the optimal host age and length of parasitization, parasitoid competition, and influence of parasitization on the longevity of females. The best rearing conditions for S. littoralis are collective parasitization of mature L3 larvae for 24 h, after at least one day of copulation. Hyposoter didymator transmits AcMNPV to both lepidopterans, but its efficiency is mediated by host preference and the pathogenicity of the BV in each host. In this particular case, H. didymator as well as AcMNPV showed a clear preference towards S. exigua. Full article

Nitrate accumulation is a major factor for the secondary salinization of greenhouse soil in China. Our previous study pointed out that a low ratio of red:far-red light (R:FR) can improve salt tolerance in pakchoi under excessive nitrate stress. However, the nitrogen metabolism mechanism is still unclear. To detect the effect of a low R:FR ratio on nitrogen metabolism of pakchoi under excessive nitrate stress, two extra additions of nitrogen of 80 mmol·L⁻¹ NO₃⁻ (H80) and 160 mmol·L⁻¹ NO₃⁻ (H160) with/without a low R:FR ratio (R:FR = 0.7) were set, and the growth index, chlorophyll content, key enzymes in nitrogen metabolism, nitrate and glutamic acid content and NRT gene expression level of pakchoi leaves were examined. The results indicated that a low ratio of R:FR could alleviate the reduction in growth and chlorophyll content in pakchoi under high-level nitrogen stress (H80 and H160). The activity of nitrate reductase (NR), glutamine synthetase (GS) and glutamine synthetase (GOGAT) decreased under H80 and H160 conditions, except of NR with the H80 treatment. The activity of glutamate dehydrogenase (GDH) increased under H80 treatment, but decreased under H160 treatment. However, the activity of GDH decreased further by reducing the ratio of R:FR. Excessive nitrate stress increased the nitrate content, and a low R:FR ratio could inhibit nitrate accumulation. However, the change in glutamic acid content was significantly increased under a low R:FR ratio without stress. Under the high-nitrogen level treatment (H160), the use of a low ratio of R:FR increased NRT gene expression. Therefore, a low R:FR ratio (R:FR = 0.7) could effectively promote the growth of pakchoi and improve its nitrogen metabolism, thus alleviating the stress effect of a high level of nitrogen in pakchoi. Full article

Dynamic particulate matter (PM) behavior on leaves depends on rainfall events, leaf structural and physical properties, and individual tree crowns in urban forests. To address this dependency, we compared the observed relationships between PM wash-off ability and leaf traits on inner and outer crown-positioned leaves during rainfall events. Data showed significant differences in the PM wash-off ability between inner and outer crown-positioned leaves relative to rainfall events due to leaf macro- and micro-structure and geometric properties among tree species. Our results showed that PM wash-off effects on leaf surfaces were negatively associated with trichome density and size of leaf micro-scale during rainfall events. Specifically, Quercus acutissima with dense trichomes and micro-level surface roughness with narrow grooves on leaf surfaces showed lower total PM wash-off in both inner (−38%) and outer (105%) crowns during rainfall. Thus, their rough leaves in the inner crown might newly capture and/or retain more PM than smooth leaves even under rainfall conditions. More importantly, Euonymus japonicus, with a thin film-like wax coverage without trichome, led to higher total PM wash-off in both inner (368%) and outer (629%) crowns during rainfall. Furthermore, we studied the changes in PM wash-off during rainfall events by comparing particle size fractions, revealing a very significant association with macro-scale, micro-scale, and geometric features. Full article

Edible fungi are often used as an important selenium (Se) source to improve human daily Se intakes as food or Se supplements because of their strong ability to accumulate Se, in which Ganoderma lucidum was widely accepted in China. However, the existing Se speciation analysis methods such as protease K-based or trypsin-protease XIV-based, have low extraction rate and enzymatic hydrolysis rate (<30%) on the Se-enriched edible fungi, resulting that it is impossible to effectively evaluate Se transformation and safety of Se-enriched edible fungi. In order to improve the extraction rate and enzymatic hydrolysis rates, 12 extraction methods (combination of buffer solutions and enzymes) including 4 two-step extraction methods and 8 three-step extraction methods were applied to extract Se from high Se-enriched Ganoderma lucidum (Total Se content 245.7 μg/g in dry matter (DW)) in the present study. The results displayed that one three-step sequential extraction method as aqueous solution extraction-pepsin extraction-trypsin extraction performed the best, by which the total Se extraction rate could reach 65%, the total Se enzyme hydrolysis rate was 40%, and the Se speciation was revealed as Selenite (63.6%), SeCys₂ (20.1%), SeMeCys (14.8%) and SeMet (1.5%) in this high Se-enriched Ganoderma lucidum. This study offers a reliable and efficient method to evaluate the Se transformation and the Se safety in high Se-enriched edible fungi. Full article

Due to the restricted genetic diversity among current asparagus cultivars, wild relatives are of particular interest as a source of resistance. In this study, seventeen cultivars and wild relatives were tested for their resistance to Fusarium oxysporum in the seedling test. Two isolates differing in virulence (single spore lines with high and low virulence) were used for testing. Most of the tested genotypes showed high infestation, whereby Asparagus aethiopicus caused no browning of the roots or growth depression. This wild relative was evaluated for its defence response after infection with F. oxysporum. For comparison, the wild relative Asparagus densiflorus and Asparagus officinalis cv. Thielim were tested. Like A. densiflorus, A. aethiopicus showed accumulation of hydrogen peroxide as a defence mechanism, while Asparagus officinalis cv. Thielim showed no storage of hydrogen compounds. Full article