Search Results (3,123)

The gasification filter cake (GFC) has great application potential for improving the characteristics of seedling substrates due to its nutrient richness and excellent water retention capacity. However, GFCs leach heavy metals easily and thus pose certain ecological risks. Sodium silicate can enhance plant resistance to heavy metal toxicity by fixing heavy metals. This study investigated the impact of sodium silicate on cucumber plant growth, the chemical characterization of the substrate, and the distribution and transfer of heavy metals. Sodium silicate was added to the seedling substrate mix at mass rates of 0 g/kg⁻¹ (GFC0), 2 g/kg⁻¹ (GFC2), 4 g/kg⁻¹ (GFC4), and 8 g/kg⁻¹ (GFC8). The seedling substrate was composed of a commercial matrix, caragana compost, and GFC (m:m 7:7:2). The GFC increased the content of total phosphorus (P), available phosphorus (P), and available potassium (K) in the substrate by 31.58%, 16.58%, and 80.10%, respectively. Conversely, the GFC decreased the plant height by 12.3%. Adding sodium silicate to the GFC increased the chlorophyll content of the plants, fixed heavy metals in the substrate, and promoted nutrient absorption and utilization by the plants. Compared with GFC0 without sodium silicate, adding sodium silicate at a mass rate of 2 g/kg⁻¹ (GFC2) reduced the chromium, lead, and cadmium contents by 51.13%, 26.37%, and 90.04%, respectively, which effectively alleviated heavy metal stress and was more conducive to plant growth. Full article

The growth of the gardening kit market could result in the increased wasting of nursery pots, which are usually made of plastic. Replacing these pots with biodegradable pots made from green waste could have benefits for climate mitigation, the circular economy, and the greenness of gardening. To address this, we introduce a prototype recycled waste leaf litter (RWLL) nursery pot. Via an incubation experiment over 90 d, we examined their biodegradability and effects on microbial enzyme activity and inorganic nitrogen concentration, comparing them with commercially available biodegradable pots, namely peat–paper mixture pots (also known as Jiffypots^®) and coco-coir pots. The effects of pot thickness were tested. Based on mass loss during incubation and on soil CO₂ efflux, the RWLL pots exhibited excellent biodegradability, regardless of their thickness, with decomposition rates and soil CO₂ efflux 1.5–6 times greater than other biodegradable pots. Biodegradability, extracellular enzyme activity, and soil inorganic nitrogen content were not affected by RWLL pot thickness or by the presence or absence of a plant in the soil. Unlike in natural ecosystems, leaf litter is treated as waste in urban green spaces, and its decomposition into soil organic matter is prevented. Creating plant pots from leaf litter enhances soil quality, reduces atmospheric carbon emissions, and satisfies the desire of gardeners for greenness. Full article

Cold plasma (CP) is a green and efficient preservation technology, but its effect on preventing the postharvest softening of fruits and vegetables is still unclear, and the effects of different CP intensities on the postharvest softening of winter jujubes (Ziziphus jujuba Mill. cv. Dongzao) have been little studied. In this study, we investigated the effects of different CP intensities (0 kV, 40 kV, and 80 kV) on the postharvest storage quality of winter jujubes and the activities of key enzymes related to softening during storage. The results showed that compared with the control group, the contents of firmness, total soluble solids (TSS), titratable acidity (TA), and vitamin C (VC) in the CP treatment group were higher and the respiratory intensity and weight loss rate were lower. In addition, CP treatment can also inhibit the degradation of protopectin and cellulose and the accumulation of soluble pectin. Moreover, CP treatment inhibited the activities of polygalacturonase (PG), pectin methyl esterase (PME), 3α-L-arabinoside (α-L-Af), 4β-galactosidase (β-gal), cellulase (Cx), and β-glucosidase (β-Glu). This shows that CP treatment has a positive effect on the preservation of winter jujubes, and the preservation effect of the 80 kV treatment was better than that of the 40 kV treatment. This provides a certain basis for cold plasma treatment in the preservation of winter jujubes. Full article

Common ragweed (Ambrosia artemisiifolia L.) is an extremely competitive broadleaved summer annual weed found in Christmas tree production systems within Michigan. Common ragweed has been reported to have resistance to glyphosate, PSII inhibitors, PPO inhibitors, and ALS herbicides. There have been reports from Michigan Christmas tree growers of common ragweed resistance to clopyralid, a synthetic auxin herbicide, in Montcalm County, Michigan. The objective of this study was to test alternative post-emergence herbicide combinations and organic mulch on clopyralid-resistant common ragweed for weed control efficacy. The following two stages of common ragweed were used: stage 1 (6–9 leaves) and stage 2 (12–14 leaves). For common ragweed in stage 1 in 2021 and 2022, as well as stage 2 in 2022, at all evaluation dates, mulch + clopyralid + oxyfluorfen provided the highest level of weed control. For stage 1 in 2022, this treatment combination provided 100% control from 2 weeks after treatment (WAT) and always showed better or equal weed control compared to all the other treatments. The combination of mulch + clopyralid + glyphosate provided 100% control by 2 WAT when plants were treated at stage 2 in 2022. For the plants treated at stage 1 in 2022, many of the treatments reached a fresh weight of 0 g, but in 2021, those same treatments resulted in a fresh weight of around 20 g. Based on fresh weight, the greatest plant growth occurred with glyphosate treatment in 2021 and clopyralid and mulch alone in 2022. This is likely due to common ragweed’s resistance to these herbicides. Full article

Nowadays, modern agriculture looks for valid, sustainable, and green alternatives that are able to improve and maintain soil quality and fertility over time. Recycling organic waste as fertilizer is one of the strategies for sustainable production. Recently, the use of new products derived from compost, such as compost tea (CT), is increasing due to their positive effects on crops. This perspective wants to give an updated shot at the effect of compost tea in horticulture. In addition to the classification of compost tea, with a focus on production procedures and composition, the possible effects they have both on the control of phytopathogens in horticulture and the influence they can have on the content of bioactive molecules and nutrients were highlighted. It is interesting to note that compost teas can have an effect on the final content of micro and macronutrients, thus improving the nutritional qualities and also increasing the content of bioactive compounds that may play a role in maintaining and improving human health. The combined use of compost tea with other treatments is being explored as a promising and innovative direction. Full article

Decay caused by Neopestalotiopsis clavispora is an important postharvest disease of blueberries that seriously affects the commercial value of blueberry fruit. In this paper, we studied the inhibitory activity and mode of action of thymol against the pathogenic fungus of blueberries caused by Neopestalotiopsis clavispora. The results demonstrated that thymol administration could limit mycelial growth in vitro; the inhibitory effect was positively connected with thymol mass concentrations, and the minimal inhibitory concentration (MIC) was 100 mg/L. Further investigations revealed that MIC thymol treatment dramatically reduced the germination of pathogenic spores and led to an increase in the conductivity of the pathogen, leakage of contents, and a decrease in pH. Propidium iodide (PI) staining experiments demonstrated that MIC thymol caused damage to mycelial cell membranes. Additionally, MIC thymol treatment promoted mycelium malondialdehyde content accumulation, inhibited superoxide dismutase (SOD) and catalase (CAT) enzyme activities, decreased adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) content and energy charge levels, and the fluorescence intensity of mycelium caused by MIC thymol treatment was significantly increased by the 2,7-Dichlorodi-hydrofluorescein diacetate (DCFH-DA) assay. The results of this study indicate that thymol suppresses the proliferation of Neopestalotiopsis clavispora by compromising the integrity of their cell membranes, promoting the accumulation of cellular reactive oxygen species (ROS), and interfering with energy metabolism. Full article

Dendrobium catenatum is a high-value medicinal plant that is predominantly found in high mountain areas, thriving amidst cliffs and rock crevices. However, its wild resources face constant threats from adverse environmental conditions, especially drought stress. Fatty acyl-CoA reductase (FAR) is crucial in plant drought resistance, but there is a lack of research on FAR genes in D. catenatum. In this study, the FAR family genes were identified from the D. catenatum genome. Their genomic characteristics were investigated using bioinformatics techniques, and their expression patterns in different tissues and under 20% PEG8000 conditions mimicking drought stress were analyzed using quantitative real-time RT-PCR (RT-qPCR). Seven DcFAR genes were identified from the D. catenatum genome. The encoded amino acids range between 377 and 587 aa, with molecular weights between 43.41 and 66.15 kD and isoelectric points between 5.55 and 9.02. Based on the phylogenetic relationships, the FAR family genes were categorized into three subgroups, each with similar conserved sequences and gene structures. The cis-acting elements of the promoter regions were assessed, and the results reveal that the DcFAR upstream promoter region contains multiple stress-related elements, suggesting its potential involvement in abiotic stress responses. The RT-qPCR results show distinct expression patterns of DcFAR genes in various plant tissues. It was observed that the expression of most DcFAR genes was upregulated under drought stress. Among them, the expression levels of DcFAR2, DcFAR3, DcFAR5, and DcFAR7 genes under drought stress were 544-, 193-, 183-, and 214-fold higher compared to the control, respectively. These results indicate that DcFAR2/3/5/7 might play significant roles in D. catenatum drought tolerance. This research offers insight into the function of DcFAR genes and provides theoretical support for breeding drought-resistant D. catenatum varieties. Full article

Flowers of Persian violet (Exacum affine Balf. f. ex Regel) that are grown in nature typically produce a scent. However, whether Persian violet flowers developed inside sterile containers produce odors has yet to be studied. Therefore, this research aimed to study and compare the effects of ex vitro and in vitro environments on the volatile composition of Persian violet flowers. Persian violet flowers obtained from an in vitro culture and potted plants were analyzed for volatile constituents using gas chromatography–mass spectrometry (GC-MS). The main constituent of the volatile compounds in the Persian violet flowers grown in both conditions was alcohol, with 3-hexen-1-ol, which produces a grassy-green odor, being the dominant substance. In addition, the in vitro Persian violet flowers contained the highest amount of ethanol, which produces a wine aroma—followed by the terpene alcohol β-citronellol, which produces a rose scent. However, 3-carene (citrus odor), caryophyllene (floral odor), humulene (woody odor), and β-ionone (floral odor) were detected onlyin Persian violet flowers grown in natural conditions. Therefore, these results indicate that hypoxia possibly occurred during plantlet growth in the in vitro environment and caused some different volatile compound production from that in natural conditions. Full article

Grapes, an important and widespread fruit crop providing multiple products, face increasing flooding risks due to intense and frequent extreme rainfall. It is thus imperative to fully understand the flood-tolerance mechanisms of grapevines. Here, RNA-seq and LC-MS/MS technologies were used to analyze the transcriptome and metabolome changes in the roots of SO4 (tolerant to flooding) and Kyoho (sensitive to flooding) grapes under flooding and post-flooding conditions. The results showed that the abundance of many metabolites in the phenylpropanoids and polyketides, organic acids and their derivatives, and organic oxygen compounds superclasses changed in different patterns between the Kyoho and SO4 grapes under flooding and post-flooding conditions. Jasmonic acid and the ascorbic acid–glutathione cycle played a pivotal role in coping with both hypoxia stress and reoxygenation stress incurred during flooding and post-flooding treatments in the SO4 cultivar. Under flooding stress, the regulatory mechanistic shift from aerobic respiration to anaerobic fermentation under hypoxia is partly missing in the Kyoho cultivar. In the post-flooding stage, many genes related to ethylene, gibberellins, cytokinins, and brassinosteroids biosynthesis and brassinosteroids-responsive genes were significantly downregulated in the Kyoho cultivar, adversely affecting growth recovery; however, their expression was not reduced in the SO4 cultivar. These findings enhance our understanding of the flooding-tolerance mechanisms in grapes. Full article

Annual plant growth patterns and seasonal conditions have both been shown to influence asparagus (Asparagus officinalis L.) root development over time. Root biomass and distribution changes in mature asparagus cultivars are herein illustrated and described. Asparagus root length density and biomass were estimated from soil cores using a systematic field sampling approach each spring. Soil cores (0.9 m deep) were divided into 0.15 m lengths and fleshy roots collected from the soil. Root length density and dry weights were determined and root distribution maps generated from collected data. As asparagus plantings matured, the sampling year had a significant influence on root development. Fleshy roots grew deeper into the soil each year but the majority of roots of Atlas, Guelph Millennium, and Jersey Giant were found in the upper 60 cm of the soil profile. For the three cultivars evaluated, minor differences in root length and root weight occurred. By Year 6, Atlas showed a decrease in root length and weight when compared to Guelph Millennium and Jersey Giant. While spear yield differences between the varieties were not significant, Atlas tended to produce more very large and large spears compared to Guelph Millennium and Jersey Giant. These results increase our understanding of asparagus root development. Full article

Foxtail lily (Eremurus), as a medicinal-ornamental geophyte, has recently emerged in the cut flower market as a novel, commercially significant specialty cut flower (SCF). However, there is limited information about the sensitivity to ethylene of foxtail lily species for managing the ethylene-mediated senescence to prolong the vase life and maintain the ornamental quality of this flower. The purpose of the current study was to compare the ethylene production rates and patterns, as well as the responses to exogenous ethylene and ethylene inhibitors, between two species, E. spectabilis and E. persicus, to better understand the role of ethylene in Eremurus inflorescence senescence. The results revealed that exogenous ethylene (10 μL L⁻¹), as a pulsing or continuous method, dramatically accelerated petal wilting in E. spectabilis and petal abscission in E. persicus. Furthermore, the rate and patterns of endogenous ethylene production varied significantly among the two investigated species. Interestingly, E. persicus exhibited a higher rate of ethylene production than E. spectabilis on the first day after harvesting, but the reverse was true at the end of the vase life (Day 4 of the vase period). The results revealed that the treatments with ethylene inhibitors considerably improved the water relations and vase longevity of both foxtail lily species. The vase life of E. spectabilis was dramatically enhanced by silver thiosulfate complex (STS) treatment (0.2 mM pulse for 24 h) from 5 d (control) to 7 d. Furthermore, 1-methylcyclopropene (1-MCP) at 0.5 and 1.0 μL L⁻¹ markedly improved water uptake, relative fresh weight, and water balance and extended the vase life of cut inflorescences by ~2 d in E. spectabilis and E. persicus, compared with those of control cut inflorescences, respectively. This research revealed that ethylene is involved in controlling the senescence of foxtail lily flowers, and two tested species exhibited distinct forms of ethylene sensitivity, including abscission type in E. persicus and wilting-type in E. spectabilis. Collectively, these findings suggest that ethylene is involved in the senescence of cut foxtail lily inflorescence and that ethylene inhibitors can prolong vase life. Full article

Cabbage is a heat-stress-sensitive cool-season crop. When exposed to high temperatures, cabbage plants can experience reduced growth, wilting, leaf yellowing, and premature bolting (the formation of a flowering stem). The regulatory mechanism controlling heat stress is poorly understood in cabbage. To investigate this mechanism, physiological changes and transcriptional profiling for different heat treatment times were analyzed in this study. The results showed that superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) activities were enhanced under heat stress. In particular, the increase in SOD and POD activities after 12 h of heat treatment was greater than that after 4 h of heat treatment. With increasing heat treatment duration, the leaf CAT activity and H₂O₂ content decreased after the initial increase. The electrolyte leakage and malondialdehyde (MDA) content dropped significantly, while the proline content increased. Alongside that, 7007 and 5537 upregulated genes were identified in the experimental group treated with heat stress for the 4 h and 12 h treatments, respectively. We found that 10,479 DEGs were shared in the heat stress treatment, of which 1241 were associated with the heat treatment time. By integrating the expression patterns and functional annotations of genes related to heat stress, we identified 15 hub genes that respond to heat stress in cabbage. Meanwhile, we had constructed a physiological to molecular model of cabbage response to long-term heat stress. These findings provide new insights for the comprehensive analysis of cabbage response to heat stress and genetic resources for breeding new varieties of cabbage with heat tolerance via genetic engineering. Full article

Heavy metals are environmental pollutants that cause toxicity in plants and represent a risk for human health, linked to bioaccumulation through the food chain. However, excess accumulation may not occur in young plants in the early stages of exposure to the toxic element. In the present work, rocket (Eruca sativa L.) plants grown in hydroponics were exposed for three weeks to excess concentrations (25, 50, or 100 µM) of Cu or Zn in the nutrient solution and were more sensitive to Cu than Zn toxicity. However, a significant decrease in the leaf biomass production as compared with the control was observed only after two or three weeks, and only minor signals of metal-induced adverse effects were evidenced concerning photosynthesis, oxidative stress indicators, antioxidant metabolites, and macronutrients. After two or three weeks, the leaf level of Cu occasionally approached the upper value associated with the recommended limits of dietary intake for human adults. However, as rocket leaves are commercialized when they achieve a 10–15 cm length, after one week of cultivation in perlite, the plants had an adequate size without metal contamination and could be considered suitable for the food market, even after exposure to Cu or Zn concentrations up to 100 µM. Full article

Papaya (Carica papaya L.) is a climacteric fruit, and its quality will rapidly decrease after ripening. Hence, the storage life of its fruit is short. D-limonene is a terpene compound in citrus essential oil and has antibacterial and antioxidant properties. The addition of D-limonene in edible coating can delay volatilization, prevent microorganism and pathogen invasion, decrease water loss, inhibit softening, decrease gas exchange, and extend the storage life of fruits. In this study, 0.25%, 0.5%, and 1% D-limonene nanoemulsion coatings were used for post-harvest immersion treatment of “Tainung No. 2” papayas and its effects on appearance, chlorophyll content, respiration rate, ethylene production, pectin methylesterase, polygalacturonase activity, decay loss, firmness, total soluble solid, titratable acidity, ascorbic acid, and total plate count were investigated. After the papayas were treated with 0.5% D-limonene nanoemulsion coating, polygalacturonase and pectin methylesterase activities decreased, fruit firmness was maintained, and ascorbic acid content was high. On the last day of storage, polygalacturonase and pectin methylesterase activities were 0.01 and 0.02 U/kg FW lower than the control group, respectively; firmness was higher than the control group by 1.75 N, and ascorbic acid content was higher than the control group by 31.97 mg/100 g FW. On Day 2, the treatment showed delay in total soluble solid accumulation and chlorophyll degradation, consequently delaying the color change in fruits. The coating decreased decay loss by 40% on Day 2, decreased respiration rate by 97.0 mg CO₂ kg⁻¹ h⁻¹, and ethylene production by 5.7 µL kg⁻¹ h⁻¹ on Day 2. Simultaneously, the coating decreased the total plate count and resulted in a good appearance. Fruits coated with a 1% D-limonene nanoemulsion coating showed defects in color change. In summary, 0.5% D-limonene nanoemulsion coating delayed “Tainung No. 2” papaya ripening and decreased microbial infection, consequently extending its storage life. Full article

Adaptation to several environmental conditions is a challenge for breeders for producing new varieties. Breeders select genotypes which show higher performance according to desired traits compared to the average of a large segregant population. In several crops, the selection index is mainly based on traits such as yield, quality, adequate plant architecture, etc. Therefore, multi-trait selection allows for the identification of genotypes that integrally exhibit a better profile and stability, in addition to the dissection of promising varieties based on their superiority in an evaluated population. In this paper, a multi-trait index included in an R tool named CropInd was used to estimate the agronomic performance of 19 sweet potato genotypes in multi-environmental evaluations (three cycles and eight locations). Here, the multi-trait index incorporated variables such as total and commercial fresh root yield, along with survival percentage, which were used in this study. Simultaneously, stability and genetic gain analysis were included to select superior sweet potato genotypes. Results showed that the CropInd script is a suitable and convenient tool for genotype selection based on multi-trait and multi-environmental data. Indexes for specific environment and general behavior (combining multi-environments) were the main output used for genotype selection. Multi-trait selection index, stability, and genetic gain analysis assisted the phenotypic selection performed by breeders. This study resulted in the selection of 0113-672COR as new variety for the Colombian Caribbean region due to its multi-trait performance and stability. Full article