Ethylene Inhibitor Research Articles

Application of 1-MCP does not slow down the ripening process of Mango (Mangifera indica L)

Fruits and vegetables are perishable so that they are easily degraded and thus have a short shelf life. Some studies have been carried out intensively to extend the shelf life of fruit with the application of 1-methylcyclopropene (1-MCP) which is an ethylene inhibitor (indirectly) to slow down the ripening process and extend its shelf life. The benefits of using 1-MCP to delay fruit softening have also been published, however the inhibition of ripening and fruit softening by 1-MCP in mango (Mangifera indica) is very limited. 1-MCP delays fruit softening during storage by indirectly inhibiting ethylene synthesis and slowing the activity of cell wall-damaging enzymes, such as pectin methyl esterase (PME). To study the effect of 1-MCP on mango fruit quality and its shelf life, the experiment was carried out by measuring weight loss, colour, firmness, vitamin C, total soluble solids, titratable acidity, and reducing sugars periodically. For all fruit samples, the pulp was chopped, frozen in liquid nitrogen, and then stored at 8°C until further use. The results showed that application of 1-MCP at room temperature did not slow down neither the senescence process nor the shelf life of mango fruit on weight loss, colour, firmness, vitamin C, total soluble solids, titratable acidity, and reducing sugars parameters.

The Physical and Structural Effects of 1-MCP on Four Different Apple Cultivars during Storage.

The impact of the ethylene inhibitor, 1-methylcyclopropene (1-MCP), on four apple cultivars (Braeburn, Fuji, Jazz and Golden Delicious) over 150 days of storage at 2 °C was assessed. Proton transfer reaction quadrupole mass spectrometry (PTR-QUAD-MS) was used to monitor changes in VOC composition, while texture analysis and X-ray microcomputer tomography (µ-CT) scanning were used to study microstructural changes. The application of 1-MCP on apples reduced VOC emissions, concurrently maintaining a firmer texture compared to the untreated apples at each time point. The µ-CT scanning revealed how changes in specific morphological characteristics such as anisotropy, connectivity and porosity, size and shape, as well as the interconnectivity of intracellular spaces (IS) influenced texture even when porosity was similar. Additionally, this study showed that the porosity and connectivity of IS were associated with VOC emission and increased simultaneously. This study highlights how the morphological parameters of an apple can help explain their ripening process during long-term storage and how their microstructure can influence the release of VOCs.

Direct organogenesis, physiochemical evaluation, chemical characterization and genetic uniformity analysis through SCoT marker in Celastrus paniculatus (Willd.): A medicinally important plant

Celastrus paniculatus (Willd.) is a rare woody climbing shrub with high medicinal value used in primary healthcare system and herbal drug formulation as its various parts have immense medicinal properties. The current study focuses to design a refined methodology for the micropropagation of C. paniculatus using young nodal segment explants. A reliable shoot multiplication protocol was attained on Murashige and Skoog (MS) medium augmented with 6-benzylaminopurine (BAP) (5.0 µ M) + meta-Topolin (mT) (2.5 µ M) + gibberellic acid (GA3) (2.5 µ M) + adenine sulphate (ADS) (20.0 µ M) which gave a maximum number of 26.0 ± 0.01 shoots/explant along with 8.5 ± 0.02 cm of shoot length. In vitro regenerated microshoots were accomplished to ex vitro rooting efficiently with a 15 min pulse treatment with two ethylene inhibitors [salicylic acid (SAA) and silver nitrate (AgNO3)] and then transfer to soilrite™. The treatment of SAA (200 μM) proved better for healthy root formation with 10.5 ± 0.017 roots/microshoot and a mean root length of 3.5 ± 0.024 cm under culture condition. The genetic stability of in vitro regenerated plantlets and mother plant was validated by start codon targeted (SCoT) primer based molecular analysis. Healthy adaptation of these plantlets to natural conditions was also revealed by numerous biochemical and photosynthetic parameters along with Scanning Electron Microscopic (SEM) analysis of leaves. Furthermore, a comparison of secondary metabolites from mother and regenerated plants was done by Gas Chromatography and Mass Spectrometry (GC-MS) analysis.

Leaf ontogeny modulates epinasty through shifts in hormone dynamics during waterlogging in tomato.

Waterlogging leads to hypoxic conditions in the root zone that subsequently cause systemic adaptive responses in the shoot, including leaf epinasty. Waterlogging-induced epinasty in tomato has long been ascribed to the coordinated action of ethylene and auxins. However, other hormonal signals have largely been neglected, despite evidence of their importance in leaf posture control. To cover a large group of growth regulators, we performed a tissue-specific and time-dependent hormonomics analysis. This revealed that multiple hormones are differentially affected throughout a 48 h waterlogging treatment, and that leaf age determines hormone homeostasis and modulates their changes during waterlogging. In addition, we distinguished early hormonal signals that contribute to fast responses to oxygen deprivation from those that potentially sustain the waterlogging response. We found that abscisic acid (ABA) levels peak in petioles within the first 12 h of the treatment, while its precursors only increase much later, suggesting that ABA transport is altered. At the same time, cytokinins (CKs) and their derivatives drastically decline during waterlogging in leaves of all ages. This drop in CKs possibly releases the inhibition of ethylene- and auxin-mediated cell elongation to establish epinastic bending. Auxins themselves rise substantially in the petiole of mature leaves, but mostly after 48 h of root hypoxia. Based on our hormone profiling, we propose that ethylene and ABA might act synergistically as an early signal to induce epinasty, while the balance of indole-3-acetic acid and CKs in the petiole ultimately regulates differential growth.

The impact of growing season on the ethylene biosynthesis and signaling pathways of a heat tolerant tomato during off-vine postharvest ripening

Ethylene initiates and mediates fruit ripening throughout a cascade of signal transductions from ethylene receptors (ETRs) to ethylene response factors (ERFs). High temperatures impair fruit ripening by suppressing ethylene biosynthesis and parts of physiological and biochemical processes. This study made use of the ethylene inhibitor (1-MCP) and exogenous ethylene to investigate the ethylene biosynthesis and signaling pathways of a heat tolerant tomato cultivar, cv. ‘Savior’, during off-vine postharvest ripening during two distinct growing seasons. Mature green ’Savior‘ tomatoes grown in winter (mild temperature) and summer (high temperature) were harvested at and treated with 1-MCP or exogenous ethylene. During off-vine ripening, summer fruit showed a different ethylene biosynthesis profile compared to winter fruit. The application of exogenous ethylene did not accelerate fruit ripening of the heat tolerant cultivar. 1-MCP suppressed ethylene production for a long time, and delayed fruit ripening of winter tomato, while for summer fruit, a limited effect of 1-MCP on inhibiting ethylene biosynthesis and delaying ripening was observed despite the strong suppression of ACC oxidase (ACO) activity. Our work also showed that a 1-MCP treatment reduced gene expression of several ethylene receptors (ETR) but did not have a strong effect on constitutive triple response (CTR), except CTR1, and ethylene-insensitive protein 2 (EIN2). Overall, our results indicate that i) ethylene biosynthesis is differentially regulated in winter as compared to summer fruit by ethylene signaling, ii) a high cultivation temperature impacts ethylene biosynthesis and ethylene sensitivity during fruit ripening despite the fact that this is a heat tolerant cultivar, iii) the expression of most ETRs and CTRs, and especially EIN2 did not respond to the 1-MCP or ethylene treatment.

Synthesis and application of Ag-doped TiO2 nanoparticles with antifungal activity and ethylene inhibition in postharvest of avocado cv. Hass

Avocado is highly susceptible to postharvest diseases and rapid ripening, making it challenging to maintain its quality and shelf life. One potential solution is the use of nanoparticles that can act as both antimicrobial agents and ethylene inhibitors. In this study, we synthesized Ag-doped TiO2 nanoparticles through a solution combustion method and subjected them to various characterization techniques, including X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. These nanoparticles were then tested for their effectiveness in combating common avocado pathogens and their ability to inhibit ethylene production. To apply our findings practically, we treated Hass avocado fruits in the postharvest stage with a suspension of Ag-doped TiO2 nanoparticles and stored them under controlled conditions to simulate the ripening process. The Ag-doped TiO2 nanoparticles formed agglomerates within the nanometric range and exhibited oxidation-reduction characteristics, effectively inhibiting ethylene production and degrading Rhodamine-B dye. Moreover, these nanoparticles displayed robust antimicrobial activity, significantly suppressing the growth of Colletotrichum gloeosporioides sensu lato pathogens. Treated fruits in the postharvest phase showed reduced microbial growth, decreased incidence of anthracnose, stem and root diseases, and an extended shelf life compared to the control group, due to ethylene inhibition. Ag-doped TiO2 nanoparticles, with their dual capabilities of antimicrobial activity and ethylene inhibition, show promise in improving postharvest management of Hass avocados. They have the potential to enhance fruit quality, reduce postharvest losses, and improve marketability. Further research and field trials are essential to fully explore the practical applications of these nanoparticles in commercial avocado production and distribution.

Differential Efficacy of Postharvest Application of Ethylene Inhibitors on Storage Life and Nutritional Quality of Guava (cv. ‘Arka Mridula’)

Differential Efficacy of Postharvest Application of Ethylene Inhibitors on Storage Life and Nutritional Quality of Guava (cv. ‘Arka Mridula’)

Inhibition of ethylene involved in resistance to E. turcicum in an exotic-derived double haploid maize population.

Northern corn leaf blight (NCLB) is an economically important disease of maize. While the genetic architecture of NCLB has been well characterized, the pathogen is known to overcome currently deployed resistance genes, and the role of hormones in resistance to NCLB is an area of active research. The objectives of the study were (i) to identify significant markers associated with resistance to NCLB, (ii) to identify metabolic pathways associated with NCLB resistance, and (iii) to examine role of ethylene in resistance to NCLB. We screened 252 lines from the exotic-derived double haploid BGEM maize population for resistance to NCLB in both field and greenhouse environments. We used a genome wide association study (GWAS) and stepwise regression to identify four markers associated with resistance, followed by a pathway association study tool (PAST) to identify important metabolic pathways associated with disease severity and incubation period. The ethylene synthesis pathway was significant for disease severity and incubation period. We conducted a greenhouse assay in which we inhibited ethylene to examine the role of ethylene in resistance to NCLB. We observed a significant increase in incubation period and a significant decrease in disease severity between plants treated with the ethylene inhibitor and mock-treated plants. Our study confirms the potential of the BGEM population as a source of novel alleles for resistance. We also confirm the role of ethylene in resistance to NCLB and contribute to the growing body of literature on ethylene and disease resistance in monocots.

Biomarkers of postharvest resilience: unveiling the role of abscisic acid in table grapes during cold storage.

Table grapes are considered non-climacteric fruit, not showing a rapid increase in respiration rate and ethylene production during ripening. Previous research has suggested that abscisic acid (ABA) may have a more crucial role in grape postharvest behaviour. This study aimed to identify biomarkers of postharvest resilience and flavour life of imported table grapes. An experiment was designed to determine i) the role of ABA and catabolites on grape berry senescence; ii) the spatial distribution of these hormones within the grape berry, and iii) the effect of 1-MCP and storage temperature on its postharvest quality. Hence, the use of an ethylene inhibitor, 1-methylcyclopropane (1-MCP), during table grape storage was investigated. Table grapes (Vitis vinifera L.) cv. 'Krissy' were subjected to i) control (untreated); and ii) 1-MCP (1 µL L-1; 12 hours; 15°C) and stored under two scenarios: i) 15 days at 0.5°C, followed by five days at 5.5°C to simulate shelf-life; and ii) 20 days at 5.5°C to simulate a higher storage temperature followed by shelf-life. Physiological (i.e. mould incidence, skin colour, firmness, respiration rate) and biochemical analysis (i.e. individual sugars, organic acids, abscisic acid and catabolites) were performed. Grapes subjected to 5.5°C showed significantly higher mould incidence at the end of the shelf-life compared to 0.5°C storage temperature (12.6% vs. 3.1%). Also, and for the first time, the spatial distribution of ABA during the senescence of table grapes was profiled; the distal section had three times more ABA and metabolites than the proximal. We demonstrated that senescence processes were initiated after a significant increase in respiration rate (from 1 to 2.8 mL CO2 kg-1 h-1), and that ABA could be considered a biomarker for table grapes senescence, since an ABA peak preceded the increase in respiration rate, mould incidence, organic acids, and sucrose hydrolysis during postharvest storage; and coincided with a decrease in berry firmness. These findings are of significant importance for the industry as understanding how ABA regulates both senescence processes and quality changes during postharvest cold storage of tables grapes can improve the consistency and reduce waste and consumer complaints.

A Novel Method for Stimulating Cannabis sativa L. Male Flowers from Female Plants.

Female hemp plants are desired in floral hemp operations due to their higher cannabinoid contents. To produce feminized seeds, a critical step of inducing fertile male flowers on female plants is performed. In feminized seed production, freshly mixed STS (silver thiosulfate + sodium thiosulfate) is applied to female plants as an ethylene inhibitor to induce male flowers. However, the short-shelf stability of the STS buffer can cause difficulty in the application and inconsistent results. Alternative methods with improved accessibility and stable buffers will be beneficial for the hemp industry and hemp breeders. A commercially available floriculture product, Chrysal ALESCO®, contains silver nitrate, the same active ingredient as STS but with increased shelf stability. This study compares Chrysal ALESCO® to the traditional STS standard methods for male flower induction on female plants and their pollen quality. The two treatments were applied to six female hemp accessions with three replicates investigated, and the male flower counts and pollen quality were compared. No statistically significant difference was discovered in their male flower counts; the STS-treated plant produced an average of 478.18 male flowers, and the Chrysal ALESCO®-treated plant produced an average of 498.24 male flowers per plant. Fluorescein diacetate (FDA) and acetocarmine stains were used to investigate the pollen quality (non-aborted rate) of two chosen genotypes. FDA-stained pollen of Chrysal ALESCO® showed a significantly higher non-aborted rate than the pollen of traditional STS-treated plants (p < 0.001); however, only a marginally higher non-aborted rate was discovered by acetocarmine staining (p = 0.0892). In summary, Chrysal ALESCO® performed equally to traditional STS treatment at male flower counts and better or equally in pollen quality. With better shelf stability and easy application, ALESCO® can be a viable alternative option for stimulating male flowers on female hemp plants.

Ethylene modulates root growth and mineral nutrients levels in trifoliate orange through the auxin-signaling pathway

Roots are fundamental to plant growth, with their development being profoundly influenced by water, mineral nutrients, and notably, plant hormones. Citrus, a leading horticultural crop cultivated globally, holds immense economic value. This study tried to investigate the roles and mechanisms effect of foliar spray 1.0 μmol/L ethephon (ETH) of ethylene and 5.0 μmol/L AgNO3 (an ethylene inhibitor) its inhibitor with auxin on root growth and mineral nutrients content levels in trifoliate orange under sand culture conditions for 45 days. Our findings indicate that ethephon treatment significantly boosted the number of lateral roots, root fresh weight, and enhanced the mineral nutrient content (N, P, K, B, Ca, Mg, Fe, Mn, and Zn, with the exception of Cu) in both root and shoot tissues. In contrast, the inhibitors notably reduced the length of lateral roots and decreased the content of P, and Fe in both root and shoot, whilst elevating Zn contents. Furthermore, ETH incited the up-regulation of auxin biosynthesis and transportation genes, leading to an increased endogenous auxin content in the lateral root-hair region. whereas, the inhibitors produced an opposite effect. We thus conclude that ethylene modulates auxin transportation and biosynthesis. This activity stimulates the auxin signaling pathway locally-specifically, in the root hair zone in the lateral root, which in turn, regulates root growth and mineral nutrient content.

Sensitivity Consequences of Ethylene in Determining the Vase Life of Eremurus spectabilis and E. persicus

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.

Ethylene inhibitors improve crop productivity by modulating gene expression, antioxidant defense machinery and photosynthetic efficiency of Solanum lycopersicum L. cv. Pusa Ruby grown in controlled salinity stress conditions

Tomato is an important horticultural crop of global importance but its susceptibility to salinity stress significantly retards growth and thereby its yield. The impact of gaseous hormone, ethylene, accentuates the effect of salinity stress by negatively regulating various growth and developmental processes. Ethylene overproduction and ionic imbalance triggered by salinity stress exhibit upregulation of 1-aminocyclopropane-1-carboxylic acid synthase (ACS) and downregulation of NHX1, SOS1 and HKT1;2 under salinity stress conditions that negatively affect proline content, ROS scavenging machinery, morphometric and physiological attributes. Variation in the proline content, activation of ROS scavenging machinery, affected morphometric and physiological attributes are some discernible points in response to salinity stress induced ethylene production. Therefore, the experiment was designed to study the role of ethylene inhibitors silver nitrate (AgNO3) and cobalt chloride (CoCl2) in mitigating the negative effects of ethylene over production under salinity stress. Tomato seedlings were treated with 0 mM NaCl, 250 mM NaCl and 250 mM NaCl + 100 µM AgNO3, 250 mM NaCl + 100 µM CoCl2 for three days. The gene expression of ACS2, NHX1, SOS1 and HKT1;2, and ACS activity, endogenous ethylene level, Na+ and K+ ions concentration, proline content, antioxidant enzymes activity, photosynthetic efficiency and different morphological and yield parameters were assessed in tomato plants treated with salinity stress, and ethylene inhibitors at 45 DAS and 90 DAS. Results revealed that ethylene inhibitors might be playing the role in minimizing the ethylene and ACC load. The ACS enzyme activity and ethylene content were considerably decreased due to application of AgNO3and CoCl2. Further, the endogenous proline and K+ content, and K+/Na+ ratio were considerably increased in response to ethylene inhibitors treatment. Also, antioxidant enzymesviz., SOD, CAT, APX and GR, growth matrices, photosynthetic efficiency and yield attributes were significantly improved in treated tomato plants (salinity with ethylene inhibitors).

Heterologous Overexpression of Apple MdKING1 Promotes Fruit Ripening in Tomato.

Fruit ripening is governed by a complex regulatory network, and ethylene plays an important role in this process. MdKING1 is a γ subunit of SNF1-related protein kinases (SnRKs), but the function was unclear. Here, we characterized the role of MdKING1 during fruit ripening, which can promote fruit ripening through the ethylene pathway. Our findings reveal that MdKING1 has higher expression in early-ripening cultivars than late-ripening during the early stage of apple fruit development, and its transcription level significantly increased during apple fruit ripening. Overexpression of MdKING1 (MdKING1 OE) in tomatoes could promote early ripening of fruits, with the increase in ethylene content and the loss of fruit firmness. Ethylene inhibitor treatment could delay the fruit ripening of both MdKING1 OE and WT fruits. However, MdKING1 OE fruits turned fruit ripe faster, with an increase in carotenoid content compared with WT. In addition, the expression of genes involved in ethylene biosynthesis (SlACO1, SlACS2, and SlACS4), carotenoid biosynthesis (SlPSY1 and SlGgpps2a), and fruit firmness regulation (SlPG2a, SlPL, and SlCEL2) was also increased in the fruits of MdKING1 OE plants. In conclusion, our results suggest that MdKING1 plays a key role in promoting tomato fruit ripening, thus providing a theoretical basis for apple fruit quality improvement by genetic engineering in the future.

H2O2-activated transcription factor MdERF4 negatively regulates ethylene biosynthetic during fruit ripening by suppressing MdACS1 transcription

Ethylene is essential for the ripening of climacteric fruit. The accumulation of reactive oxygen species (ROS) in apples can accelerate fruit ripening. Although ethylene signaling has been extensively studied, the transcriptional regulation of ethylene biosynthesis combined with ROS signaling remains limited. Hydrogen peroxide (H2O2) is one of the most abundant ROS involved in fruit development, ripening and senescence. Therefore, we treated apple fruit with different concentrations of H2O2 and found that low concentrations of H2O2 stimulated the activities of antioxidant enzymes, improved the scavenging ability of ROS, and reduced ethylene production·H2O2, as a signaling molecule, activated the expression of MdERF4, which can directly bind to proMdACS1 and suppress its expression, thereby inhibiting ethylene synthesis. Moreover, H2O2 indirectly attenuated the expression of MdACS1 and reduced ethylene production, thereby prolonging the storage period of the fruit by indirectly promoting the inhibitory effect of the ethylene inhibitor MdERF4 on proMdERF3. Our findings provide insights into the transcriptional regulation of ethylene biosynthesis during fruit ripening.

Enhancing Anna Apples’ Productivity, Physico-Chemical Properties, and Marketability Using Sprays of Naphthalene Acetic Acid and Inhibitors of Ethylene for Alleviating Abiotic Stresses

In order to improve the resistance of apples to stresses (abiotic stresses) during hot and dry summers to enhance their productivity and marketability, Anna apple trees were treated with aminoethoxyvinylglycine (AVG), 1-methlcyclopropene (1-MCP), and naphthalene acetic acid (NAA), alone, or in combination, in two successive seasons. All treatments significantly increased the yield per tree, the average fruit volume, fruit diameter, and fruit weight compared to the control (growing under hot and dry summers without any treatments). All treatments significantly reduced the apple size, total soluble solid (TSS) content, anthocyanin content, carotenoid content, total sugar solids, and sugar percentage, and they led to fruit softening, loss of fruit weight, firmness, breakdown percentage, as well as a decreased polyphenol oxidase and peroxidase activity at one-week post-harvest (except for 20-ppm NAA) in comparison with the control. Trees treated with 320-ppm 1-MCP + 250-ppm AVG exhibited maximum yield per tree, fruit firmness, and no-reducing sugars or starch. On the other hand, the 20-ppm NAA produced the maximum TSS content, total sugars, with a reduced sugar percentage, carotenoid and anthocyanin fruit content, and (TSS)/acidity ratio. The application of 320-ppm 1-MCP + 250-ppm AVG effectively delayed the harvest for 14 days compared to the control. Our results show that the sprays of NAA and inhibitors of ethylene had a significant effect on the productivity and marketability of Anna apples under abiotic stresses.

A complex network regulating malate contents during fruit ripening in climacteric fruits.

This article is a Commentary on Wang et al. (2023), 239: 1014–1034.

Postharvest Treatments of Hass Avocado (Persea americana Mill.) and Estimation of Its Quality Using Hyperspectral Imaging (HSI)

Avocados’ shelf life is limited and difficult to monitor. This study evaluated the performance of chitosan coatings (1.5 and 2% w/v, T1 and T2) on avocados’ quality and shelf life against samples untreated (C) and treated with an ethylene inhibitor (1-MCP, M). Hyperspectral imaging (HSI) coupled with machine learning (ML) techniques was also evaluated to estimate Hass avocados’ quality indicators. Sensorial, physicochemical, and metabolic characteristics were measured using standard procedures. While T2 samples exhibited undesirable changes (i.e., uneven color and heterogeneous firmness), T1 behaved similarly to C. However, neither treatment could delay senescence as much as 1-MCP (42 vs ≤ 33 days). In general, Bayesian regularization neural networks (BRNNs) outperformed the other tested ML techniques in estimating quality attributes from HSI features, allowing for real-time nondestructive assessment of food quality. Adverse effects of chitosan coatings on avocados’ physiology were identified, which can inform the development of films with improved performance.

Ethylene inhibition with silver nitrate (AgNO3) and pyrazinamide (PZA) ameliorates in vitro salt tolerance of tomato (Lycopersicon esculentum L) plantlets

Ethylene inhibition with silver nitrate (AgNO3) and pyrazinamide (PZA) ameliorates in vitro salt tolerance of tomato (Lycopersicon esculentum L) plantlets

Heat-induced Leaf Senescence in Creeping Bentgrass Suppressed by Aminoethoxyvinylglycine Involving Regulation of Chlorophyll Metabolism

Heat stress-induced or stress-accelerated leaf senescence is related to the accumulation of ethylene and loss of chlorophyll in cool-season grass species. The objective of this study was to determine whether foliar-spraying the ethylene inhibitor, aminoethoxyvinylglycine (AVG), may suppress heat-induced leaf senescence through effects on chlorophyll synthesis and degrading enzymes in creeping bentgrass (Agrostis stolonifera). Plants were maintained in environmentally controlled growth chambers under non-stress (22/17 °C day/night) or heat stress (35/30 °C day/night) temperature conditions for 25 days, and turf quality, electrolyte leakage, and chlorophyll content were measured to assess the extent of leaf senescence. Activities of chlorophyll-synthesizing and chlorophyll-degrading enzymes were quantified to determine whether AVG may regulate chlorophyll metabolism. Plants were foliar-sprayed with 25 µm AVG before and during heat stress at 7-day intervals. From 21 through 25 days of heat stress, AVG-treated plants had significantly higher turf quality and chlorophyll content, whereas electrolyte leakage was significantly lower in comparison with untreated controls. The activity of a chlorophyll-synthesizing enzyme, porphobilinogen deaminase, was significantly increased in AVG-treated plants at 21 days of heat stress. The activity of chlorophyll-degrading enzymes was significantly lower in plants treated with AVG from 14 through 25 days of heat stress for peroxidase, from 21 through 25 days of heat stress for pheophytinase, and at 25 days of heat stress for chlorophyllase. AVG may have suppressed heat-induced leaf senescence by regulating chlorophyll metabolic activities in cool-season grass species.