Sugar Content Research Articles

Design and Demonstration of a Novel Interferometric Polarimeter for Quantitative Determination of Sugars in a Solution

Accurate quantification of sugar in food and pharmaceutical products is important to achieve the desired levels of sweetness, texture, flavor and nutritional content. This article introduces a novel polarization-sensitive interferometric method for measuring the concentration of sugar in solutions. The impact of sugar concentration is investigated by analyzing the visibility of the interference pattern using a Mach-Zehnder interferometer with an interference pattern scanning and recording system. The visibility of the interference fringes is determined by cross-sectional scanning of the fringe pattern from its center over the photodetector, followed by cut-profile analysis. As the concentration of sucrose, glucose and fructose increases, a gradual decrease in interference pattern visibility is observed, following a parabolic trend within the broader detection range of 0–14 g/50 ml. The sensor’s performance is divided into two linear regions: region-1 (0–6 g/50 ml) and region-2 (6–14 g/50 ml). In region-1, fructose exhibited the highest sensitivity of 0.0195 (g/50 ml)-1, which is 6.09 times and 1.89 times higher than glucose and sucrose, respectively. Similarly, in region-2, fructose showed a sensitivity of 0.077 (g/50 ml)-1, surpassing glucose by 3.56 times and sucrose by 2.41 times. However, sucrose achieved the lowest limit of detection of 0.0021 g/ml, which is 2.76 times and 1.71 times better than glucose and fructose, respectively. The decreasing trend in interference pattern visibility is further validated through irradiance and optical rotation measurements of the laser beam passing through the sugar solutions relative to the reference laser beam. Results from both optical techniques demonstrated good agreement, with average deviations of 1.75%, 1.72%, and 4.24% for sucrose, glucose and fructose, respectively. The proposed technique is universally applicable for measuring the concentration of transparent, optically active solutions and has the potential to be a valuable tool for quality control and optimization in the food and pharmaceutical industries.

Contribution of pectin-degrading bacteria to the quality of cigar fermentation: an analysis based on microbial communities and physicochemical components

ObjectiveThis study aims to investigate the effects of pectin-degrading bacteria on the microbial community and physicochemical properties during the fermentation process of cigar tobacco, evaluating its potential in reducing green bitterness and enhancing aroma.MethodsBy isolating and screening pectin-degrading bacteria, high-throughput sequencing and physicochemical analysis were employed to compare the microbial flora and physicochemical component differences in different treatment groups of cigar tobacco. Furthermore, correlation analysis was performed to examine the relationships between these variables.ResultsThe results showed that the strains YX-2 and DM-3, isolated from the cigar tobacco variety “Yunxue No. 1,” exhibited strong pectin-degrading abilities. Phylogenetic analysis revealed that strain YX-2 is highly homologous to Bacillus flexus, while strain DM-3 is highly homologous to Bacillus siamensis. After fermentation, the addition of strains YX-2 and DM-3 significantly reduced the pectin content in the tobacco leaves, increased the total sugar and reducing sugar content, reduced green bitterness, and markedly enhanced the total aroma components. Notably, DM-3 exhibited outstanding performance in the production of Maillard reaction products. Microbial community analysis showed that the addition of pectin-degrading bacteria significantly increased the diversity of both bacteria and fungi, especially in the TDM3 group, where the relative abundance of Pseudomonas was notably elevated. Correlation analysis revealed that Pseudomonas had a significant positive correlation with both reducing sugar and total sugar, and a significant negative correlation with pectin, indicating its important role in sugar metabolism and pectin degradation. Additionally, fungal genera such as Cercospora were significantly negatively correlated with total sugar and total nitrogen, while Eurotium was closely associated with pectin degradation and reducing sugar accumulation.ConclusionThis study found that the addition of Pectin-degrading bacteria YX-2 and DM-3 significantly optimized the microbial community structure during the cigar tobacco fermentation process and improved the physicochemical properties of the tobacco leaves, with notable effects in reducing green bitterness and enhancing aroma.

Repeated Fed-Batch Culture Strategy for the Synthesis of Polyhydroxybutyrate (PHB) Biopolymers from Sugar Cane Juice Using Azotobacter vinelandii

In this research work, a main biopolymer group of polyhydroxyalkanoates (PHAs) in the form of polyhydroxybutyrate (PHB) was synthesised by a pure bacterial strain of Azotobacter vinelandii via repeated fed-batch fermentation. An agricultural crop, sugar cane, was used as the sole carbon source. Firstly, batch fermentation was investigated considering variations in incubation times (24 h, 48 h, and 96 h). The highest dry cell weight (DCW) and PHAs of 5.15 ± 0.04 g/L and 4.00 ± 0.04 g/L were obtained after 48 h of incubation time. The optimum time obtained was further varied to investigate the effect of the sugar concentrations in the medium. It was found that bacteria could grow very well and produced the highest DCW and PHAs (11.17 ± 0.15 g/L and 8.77 ± 0.06 g/L) when the culture medium with a 100 g/L sugar concentration was added. Later, repeated fed-batch fermentation was carried out to improve productivity. The results obtained revealed that PHA production was increased in the next cycle of the process. Furthermore, the final productivity (0.104 g/L·h) was increased 1.65-fold compared to the first cycle (0.063 g/L·h). Moreover, the culture strategy showed remarkable results, with reductions in both fermentation time and preparation cost.

Evaluation and character association study for tuber yield, biochemical and antioxidant properties of sweet potato (Ipomoea batatas)

A study was carried out during 2022 and 2023 at ICAR-Research Complex for North-Eastern Hill Region, Umiam, Meghalaya to evaluate the yield, biochemical and antioxidant properties of 49 accessions of sweet potato [Ipomoea batatas (L.) Lam.] in mid hill condition of north-eastern region. The experiment was laid out in randomized block design (RBD) with 3 replications. Results indicate that Mynthlu Orange exhibited the highest tuber weight, length, diameter and yield. In terms of biochemical parameters, Meghalaya Local recorded the highest dry matter content; Col-6 recorded the highest starch content; and X-24 had the highest total sugar content. Among antioxidants, X-24 showed the highest total phenolic content, highest FRAP assay value and anthocyanin with lowest IC50 value which signified that X-24 had the highest antioxidant activity. Correlation study revealed significant positive correlation of tuber yield with tuber weight, diameter and total anthocyanin. Based on the mean performance, accessions Mynthlu Orange, X-24 and Col-6 were found promising for yield, biochemical and antioxidant parameters.

Overexpression of vacuolar H+-pyrophosphatase from a recretohalophyte Reaumuria trigyna enhances vegetative growth and salt tolerance in transgenic Arabidopsis thaliana

Reaumuria trigyna, a wild and endangered salt-secreting small shrub, is distributed in arid and semi-arid areas of Inner Mongolia, China. An H+-pyrophosphatase gene (RtVP1) was isolated from R. trigyna according to transcriptomic data, which encoded a plasma membrane and tonoplast-localized protein. RtVP1 was quickly upregulated by NaCl and exogenous abscisic acid treatment and rescued the sucrose deficiency sensitive phenotype of the AtVP1 mutant (avp1). Transgenic Arabidopsis overexpressing RtVP1 exhibited a higher leaf area, plant height, fresh weight, root length, and soluble carbohydrate accumulation compared to the wild type (WT) under normal conditions. RtVP1 overexpression increased the seed germination rate and decreased the reduction rate of fresh weight, root length, and chlorophyll content in transgenic plants under salt stress. Catalase enzyme activity, proline content, relative water content, and soluble sugar content were significantly increased in transgenic Arabidopsis under salt stresses, but the malondialdehyde content was dramatically decreased. More K+ and less Na+ were accumulated in transgenic Arabidopsis leaves, resulting in a relatively lower Na+/K+ ratio. In transgenic Arabidopsis roots, K+ was unchanged, but Na+ and the Na+/K+ ratios were reduced compared to those in WT. More Na+ and K+ were accumulated in the intracellular of transgenic yeast, and the Na+/K+ ratio was significantly reduced compared to the control. These results showed that R. trigyna RtVP1 promotes the vegetative growth of plants, mainly by regulating carbohydrate metabolism, and confers salt tolerance in transgenic Arabidopsis by maintaining Na+/K+ homeostasis and enhancing the antioxidant and osmotic regulatory capacity. These results indicated that RtVP1 can serve as an important candidate gene for genetic improvement of crop yield and salt tolerance.

Short-Term Flow Velocity Stress on the Behavioral, Physiological, and Biochemical Responses of the Large Yellow Croaker (Larimichthys crocea)

Flow velocity is a key environmental factor that affects the behavioral strategies and physiological homeostasis of fish. To study the effects of flow velocity on the behavioral changes and blood physiology of the yellow croaker, the behavioral patterns of yellow croakers in response to flow velocity stress were obtained by analyzing changes in tail wagging frequency and amplitude. Differences in blood glucose, lactate, and cortisol were compared to determine their appropriate flow rate ranges. The juvenile stage of the large yellow croaker is crucial, as environmental changes can affect the physiology of fish. Therefore, juvenile yellow croakers were selected as the experimental subjects for this study. Twenty-four healthy and uniformly sized large yellow croakers with body weights of (90.26 ± 9.91) g and body lengths of (19.91 ± 0.69) cm were randomly assigned to one control group and three experimental groups, with five fish in each group. The experimental group was set with three flow rates, namely 1 bl/s (20 cm/s), 2 bl/s (40 cm/s), and 3 bl/s (60 cm/s), with a flow rate stress duration of 1 h. The results showed that: (1) Under different flow velocities, the fish exhibited different tail wagging patterns. At low flow velocities, their tail fins exhibited a “C”-shaped swing, while at high flow velocities, their bodies exhibited an “S”-shaped swing. (2) Oscillation frequency and amplitude both increased with increasing flow velocity. At a flow velocity of 2 bl/s, the oscillation frequency significantly increased. When the flow velocity reached 3 bl/s, the oscillation amplitude significantly increased (p < 0.05). (3) Blood physiology showed significant changes with increased flow rate, and blood glucose content continuously decreased with increased flow rate, significantly decreasing at a flow rate of 2 bl/s (p < 0.05). Lactic acid and cortisol both increased with increasing flow rate, and significantly increased at a flow rate of 3 bl/s (p < 0.05). In summary, under high-flow velocity stress, significant changes occurred in the behavior and physiology of large yellow croakers, which were consistent with physiological changes in the blood. A flow rate higher than 2 bl/s can lead to intense swimming behavior, decreased blood sugar concentration, and increased lactate accumulation and stress levels. Therefore, the short-term tolerance of yellow croakers is 2 bl/s, and a flow rate of 1 bl/s is more suitable.

Impact of Exopolysaccharides from Fructilactobacillus sanfranciscensis Ls5 on the Quality of Mantou: A Comparative Study of Fermentation Conditions

Lactic acid bacteria (LAB) and their exopolysaccharides (EPS) have the potential to enhance the quality of flour-based products. This study investigated the effect of EPS produced by Fructilactobacillus sanfranciscensis Ls5 on the quality of Mantou. LAB strains with high EPS production were isolated from traditional fermenters, and their characteristics and EPS properties were examined. Four different fermentation conditions (Blank, Yeast, Ls5-Yeast, and EPS-Yeast) were compared in terms of their effects on the physicochemical properties, in vitro digestion characteristics, and shelf-life of Mantou. The incorporation of Ls5 and its EPS into Mantou resulted in a lower dough fermentation pH, increased organic acid production, and enhanced fermentation activity. Additionally, the incorporation of Ls5 and its EPS led to significant improvements in the quality of the Mantou, including the extension of shelf-life, improved sensory evaluation, and a reduction in the sugar content. Additionally, there was an increase in resistant starch content during digestion in both types of Mantou, which could offer potential benefits to human glycemic health.

Contextual factors in selecting added versus naturally occurring sugars on fruit and vegetable beverages: emphasising the role of social context

PurposeThis study examines the consumption of fruit and vegetable (FV) beverages, distinguishing between sugar content, whether from added sugar (AS) or naturally occurring sugar (NOS). While FV beverages are widely perceived as a healthier alternative to other beverages, concerns about their sugar content persist, particularly for AS-sweetened beverages. This study examines the situational contexts (e.g. physical context, social context and temporal conditions) and food pairing contexts (vice versus virtue foods) that influence the selection of AS- over NOS-sweetened FV beverages. Furthermore, it also examines how situational factors and food pairing contexts interact to shape individuals’ FV beverage selection behaviour.Design/methodology/approachThis study used food diary data from March 2019 to May 2022 in South Korea, concentrating on the consumption of ready-to-drink FV beverages with food.FindingsThe results reveal specific situational contexts that increase the likelihood of choosing AS-sweetened FV beverages. In addition, AS-sweetened ones are more likely to be paired with vice foods, whereas NOS-sweetened ones are more likely to be paired with virtue foods. Furthermore, the study shows a significant interaction effect of the social context with paired food menus on FV beverage selection behaviour.Originality/valueThe consumer-centred approach of the study provides valuable insights into the decision-making processes behind FV beverage consumption. It validates that AS- and NOS-sweetened FV beverages are consumed in different situational contexts and with distinct food menus, enabling individuals to make healthier choices in their own consumption context.

LC-MS/MS-based metabolic profiling: unraveling the impact of varying degrees of curing on metabolite transformations in tobacco

The curing process regulates metabolite transformations of leaves and significantly influences the formation of tobacco quality. This study investigated the major physicochemical compositions and metabolic profiles under normal curing (NC), excessive curing (EC), and insufficient curing (IC) treatments. The results indicated that the contents of nicotine, nitrogen, potassium, and chlorine remained stable among treatments, while the sugar content in EC was significantly lower than in IC. LC-MS/MS identified 845 metabolites, with flavonoids as the most abundant class. Comparative analyses identified a series of differentially expressed metabolites (DEMs) among fresh leaf, NC, EC, and IC leaves at the end of 42°C, 54°C, and 68°C, respectively. At the end of 68°C, 256 up-regulated and 241 down-regulated common DEMs across treatments were isolated in comparison to fresh leaf, underscoring the consistency of metabolic changes during curing. Notably, nonivamide varied markedly across treatments, suggesting its potential as a key curing indicator. NC_68°C displayed 11 up-regulated and 17 down-regulated unique DEMs, differing from EC_68°C and IC_68°C, suggesting their potential availability in evaluating tobacco leaf quality. KEGG pathway analysis revealed temporal shifts in metabolic pathways, particularly those involved in secondary metabolite biosynthesis (such as flavonoids, flavones, flavonols) and amino acid metabolism, during the transition from yellowing to color-fixing. Correlation analysis isolated the top 25 DEMs correlated with curing degree and stage, which might play pivotal roles in the curing process and could serve as potential biomarkers for assessing curing degree and stage. Specifically, D-(+)-cellobiose displayed the strongest negative correlation with curing degree, while 5,7-dihydroxychromone exhibited the highest positive correlation coefficient. Furthermore, curcurbitacin IIa showed the highest positive correlation with curing stage, followed by hesperetin and 8-shogaol. Additionally, random forest analysis emphasized morellic acid as a core molecular metabolite across curing degrees, suggesting its potential as a biomarker. Debiased sparse partial correlation (DSPC) network analysis further pinpointed hispidulin as a key metabolite, underscoring its significance in elucidating flavonoid metabolism during the curing process. Collectively, this study enhances the understanding of metabolite transformations underlying tobacco curing processes and provides a valuable reference for optimizing curing strategies to achieve desired outcomes.

Comprehensive utilization of Aspergillus niger waste mycelium based on physically induced autolysis: Preparation of chitosan and alternative nitrogen source

In industrial fermentation of citric acid, vast quantities of mycelium from Aspergillus niger (MAN) are produced, with an annual output of 20 million tons in China alone. The disposal of waste MAN poses a significant challenge and signifies a missed opportunity for resource recovery. In this study, physically induced autolysis (PIA) was employed to utilize the MAN proteins and chitosan. The results indicated abundant soluble proteins and sugars were released into the supernatant, while the cell fragments can be used to prepare chitosan. Under optimized autolytic conditions, the rate of total protein utilization of MAN was 78.7 %, and the rate of reserved chitin in the cell fragment was 93.8 %, outperforming other techniques. These findings were consistently reproducible in larger-scale experiments. Chitosan was prepared from cell fragments that eliminated the need for acid treatment and reduced alkali utilization by 50–67 %, thanks to PIA's effective removal of proteins from cell fragments. The rate of total sugar utilization, including both the content of the soluble sugars from autolysate and prepared chitosan, was 75.42 % of the total sugar of MAN. Additionally, the autolysate was proved to be an alternative nitrogen source in the fermentation media for microbial production of 2, 3-butanediol and citric acid, yielding concentrations comparable or superior to traditional sources. Thus, our findings not only achieved high component utilization rates but also facilitated environmentally friendly chitosan preparation, indicating the potential for innovative approaches to convert waste mycelium into valuable resources and advance the industry towards more efficient practices.

Identification of Primary Metabolite Profiles Reveals Quality Characteristics of Citrus maxima ‘Shatian Yu’ from Different Origins

Citrus maxima ‘Shatian Yu’ displays varying nutritional profiles influenced by its production area. This study evaluated pomelo fruits from four primary and one developing ‘Shatian Yu’ production area. Notably, ‘Shatian Yu’ from the Guilin area exhibited higher sugar and alcohol content, suggesting enhanced taste. Principal component analysis and OPLS-DA revealed significant metabolite differences among production areas. In Guilin, variations were observed in a few substances, including sugars, alcohols, and phenolic acids. When compared with Rong City, Guilin showed a decrease in four phenolic acids and an increase in three organic acids, eighteen amino acids, eighteen lipids, and one vitamin. This comprehensive analysis provides valuable insights for the development of ‘Shatian Yu’ cultivation, highlighting the impact of production areas on fruit quality.

Balanced Fertilization Enhances the Nutritional Value and Flavor Profile of Tomato Fruits

The tomato is a key fruit in China. However, the drive to produce higher-quality tomatoes has resulted in fertilizer overuse, soil degradation, and environmental pollution in recent years. Therefore, investigating the effects of balanced fertilization on the nutritional and flavor qualities of tomato plants is crucial. This study applied four fertilizer treatments to assess their effects on sugar and acid contents, sugar-metabolism-related enzyme activity, nitrate levels, ascorbic acid, pigments, polyphenols, and volatiles, and we performed a correlation analysis. The results showed that balanced fertilization increased glucose and fructose contents by 45% and 31% compared to CK (conventional fertilizer), while tartaric, citric, acetic, malic, and shikimic acid contents were reduced by 59%, 27%, 22%, 26%, and 4%, respectively. Additionally, balanced fertilization increased the activities of sucrose synthase (SS), sucrose phosphate synthase (SPS), acid invertase (AI), and neutral invertase (NI) by 58%, 26%, 19%, and 35%, respectively, compared to CK (conventional fertilizer) and upregulated the expression of phosphoenolpyruvate carboxykinase (PEPCK), neutral invertase (NI), sucrose-phosphate synthase (SPS), and fructose-1,6-bisphosphatase (FBP) genes. Moreover, balanced fertilization significantly enhanced the polyphenol content, as well as the diversity and concentration of volatiles. Correlation analysis confirmed that sugar-metabolism-related enzymes and genes were positively correlated with sugar fractions and negatively correlated with the organic acid content. Principal components analysis demonstrated that the balanced fertilization treatment was distinct from the other treatments, and all polyphenols, except for caffeic acid, were positively associated with balanced fertilization.

Exogenous nitric oxide extends longevity in cut Lilium tigrinum flowers by orchestrating biochemical and molecular aspects

Senescence represents a developmentally orchestrated and precisely regulated cascade of events, culminating in the abscission of plant organs and ultimately leading to the demise of the plant or its constituent parts. In this study, we observed that senescence in cut Lilium tigrinum flowers is induced by elevated ABA levels and the hyperactivation of lipoxygenase (LOX) activity. This cascade increased ROS concentrations, heightened oxidative damage, and disrupted cellular redox equilibrium. This was evidenced by elevated lipid peroxidation, attenuated antioxidant machinery, and reduced membrane stability index (MSI). Despite its known role in delaying flower senescence, the specific biochemical and molecular mechanisms by which nitric oxide (NO) regulates senescence in cut L. tigrinum flowers are not fully elucidated. Specifically, the interactions between NO signaling and ABA metabolism, the regulation of protease activity, and the influence of NO-mediated ROS scavenging, senescence-associated gene expression requires further exploration. Exogenous application of sodium nitroprusside (SNP), a source of NO, mitigated senescence in L. tigrinum cut flowers by upregulating the activity of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and reducing the LOX activity, an indicator of lipid peroxidation. SNP treatment also downregulated the relative expression of senescence-associated gene (SAG12),lipoxygenase 1 (LOX1), and abscisic aldehyde oxidase 3 (AAO3). NO also upregulated defender against apoptotic death 1 (DAD1) expression correlated with minimized protease activity and reduced α-amino acid content in SNP-treated tepals. This regulation was accompanied by increased contents of sugars, proteins and phenols and reduced abscisic acid content, which collectively delayed the senesecence and enhanced the longevity of L. tigrinum cut flowers. This study demonstrates that exogenous SNP application can effectively mitigate senescence in cut L. tigrinum flowers by modulating antioxidant enzyme activities, reducing oxidative stress, and regulating the expression of key senescence-associated genes. This study unravels the complex molecular networks involved in NO-mediated senescence delay, which may lead to the development of innovative approaches for improving flower longevity.

ZmCCD8 regulates sugar and amino acid accumulation in maize kernels via strigolactone signalling

SummaryHow carbon (sucrose) and nitrogen (amino acid) accumulation is coordinatively controlled in cereal grains remains largely enigmatic. We found that overexpression of the strigolactone (SL) biosynthesis gene CAROTENOID CLEAVAGE DIOXYGENASE 8 (CCD8) resulted in greater ear diameter and enhanced sucrose and amino acid accumulation in maize kernels. Loss of ZmCCD8 function reduced kernel growth with lower sugar and amino acid concentrations. Transcriptomic analysis showed down‐regulation of the transcription factors ZmMYB42 and ZmMYB63 in ZmCCD8 overexpression alleles and up‐regulation in zmccd8 null alleles. Importantly, ZmMYB42 and ZmMYB63 were negatively regulated by the SL signalling component UNBRANCHED 3, and repressed expression of the sucrose transporters ZmSWEET10 and ZmSWEET13c and the lysine/histidine transporter ZmLHT14. Consequently, null alleles of ZmMYB42 or ZmMYB63 promoted accumulation of soluble sugars and free amino acids in maize kernels, whereas ZmLHT14 overexpression enhanced amino acid accumulation in kernels. Moreover, overexpression of the SL receptor DWARF 14B resulted in more sucrose and amino acid accumulation in kernels, down‐regulation of ZmMYB42 and ZmMYB63 expression, and up‐regulation of ZmSWEETs and ZmLHT14 transcription. Together, we uncover a distinct SL signalling pathway that regulates sucrose and amino acid accumulation in kernels. Significant association of two SNPs in the 5′ upstream region of ZmCCD8 with ear and cob diameter implicates its potential in breeding toward higher yield and nitrogen efficiency.

The Development and Characterisation of a Sustainable Plant-Based Sweet Spread Using Carob as a Cocoa and Sugar Replacement

Cocoa prices are predicted to rise continually, as demand remains high and there are supply issues caused by crop yield fluctuations. This study aimed to develop a sustainable plant-based sweet spread using functional plant-based ingredients, chickpeas and carob, as a cocoa and sugar alternative. Recipe optimisation resulted in the production of a control sample made using cocoa and three experimental samples containing varying proportions of carob (50%, 75%, and 100%). The samples were analysed for their physicochemical characteristics (water activity, pH, colour, and texture) and proximate composition (moisture, ash, carbohydrate, sugars, starch, protein, fat, and energy). Using carob as a cocoa substitute significantly decreased the pH, firmness and stickiness, fat and energy contents. On the other hand, increasing the percentage of carob led to a substantially higher sugar content in the sweet spreads. The results show the possibility of developing an innovative sustainable plant-based chocolate-flavoured spread with favourable physicochemical characteristics and nutritional profiles using carob powder and syrup as a cocoa and sugar replacement.

Effects of pretreatment in a temporary immersion bioreactor on organogenesis efficacy of <i>Lilium candidum</i> L. bulbscales

Our experiment was conducted in two stages, i.e., pretreatment (first stage) and regeneration (second stage). The first stage was carried out in a liquid Murashige and Skoog basal medium (5 µM BAP and 0.05 µM NAA) in a bioreactor with a RITA temporary immersion system under the light of a fluorescent lamp. Explants (bulbscales) were immersed in the medium once a day for 15 minutes (RITA 1×15) or three times a day for 1 (RITA 3×1), 5 (RITA 3×5), and 15 minutes (RITA 3×15) for one to six weeks. For regeneration, the explants were transferred onto a solid medium of the same composition for another six weeks. The bulbscales not exposed to the liquid medium were used as a control. Biomass weight, biomass growth index, number and percentage of dry matter of bulblets, and the content of soluble sugars in the bulblets and in the liquid medium were examined. The bulblets were formed in all combinations from the third week of the culture, and their number increased in the RITA 3×15 combination for both the first and the second stages of the experiment. After the longest, 6-week pretreatment, more bulblets were obtained than in the control. Their fresh weight after six weeks of regeneration was positively associated with extended pretreatment time. This was in contrast with the dry weight of the bulblets, which decreased in the second stage of the experiment along with the extension of its first stage. Prolonged contact of the explants with the liquid medium during the pretreatment resulted in a higher content of soluble sugars in the bulblets at both stages of the experiment. The content of soluble sugars in the liquid medium decreased over time in all tested combinations. After six weeks of bioreactor culture, the lowest level of soluble sugars was observed in the RITA 3×15 combination.

Evaluation of yield and stability of sugar beet (beta vulgaris L.) genotypes using GGE biplot and AMMI analysis

Rhizomania is the most destructive sugar beet disease in the world, and in recent years, it has widespread in most of the sugar beet growing areas in Iran. Since the control of this soil-borne disease is a difficult task, the use of resistant genotypes is known as the best measure against the disease. The ultimate goal of sugar beet breeders is to produce genotypes that can be used in both infected and non-infected fields without any reduction in terms of yield and quality. Twenty-one sugar beet genotypes along with four controls were evaluated in randomized complete block design with four replications in fields with natural infection to rhizomania in five research stations. Important sugar beet traits including root yield, sugar yield, sugar content, and white sugar yield were evaluated for two years (2021 and 2022). For all traits, location was the main source of variation that spanned 33 to 55% of the total sum of the square followed by the location×year×genotype accounted for 3–40% of the variation. Based on the results of analysis of variance, multivariate stability parameters were computed to evaluate the genotypes’ stability. The first two principal components (IPCA1 and IPCA2) generated by GGE biplot contributed for 31.3 and 17.5% difference in genotype×environment interaction for root yield, respectively. According to the GGE biplot, genotypes RM-11 and RM-12 were identified as the winning genotypes across environments for both root yield and white sugar yield traits whereas AMMI model identified RM-14 and RM-9 (for root yield) and RM-1 (for white sugar yield) as best genotypes. Based on the ideal genotype ranking, RM-11 and RM-10 were the best performer with a high mean yield as well as stability in the studied environments. The biplot rendered using the weighted average of absolute scores (WAASB) and root yield and white sugar yield identified RM-11 and RM-9 as superior genotypes in terms of yield and stability. The selected genotypes can be used in breeding programs to transfer the disease resistance and cultivar development.

Impacts of increased temperatures on floral rewards and pollinator interactions: a meta-analysis

Flowering plants produce pollinator rewards such as nectar and pollen, whose quantity and quality usually depend on the whole-plant state under specific environmental conditions. Increasing aridity and temperature linked to climate change may force plants to allocate fewer resources to these traits, potentially disrupting plant-pollinator interactions. In this study, for the first time, both quantitative review (vote-counting procedure) and meta-analytic approach were used to assess the implications of increased temperatures linked to global warming on floral rewards, including nectar (sugar concentration, content, and volume) and pollen (germination and viability), as well as on pollinator visits. Furthermore, we explored whether observed effects of warming are related either to temperature range, plant type (wild vs crop), or study approach (greenhouse vs field experiments). We also assessed the correlations between elevated temperatures and the characteristics that were affected by the temperature range. The results of the vote-counting technique showed that higher temperatures led to a decrease in floral rewards but did not affect the number of pollinator visits. Concurrently, meta-analysis detected adverse effects of warming on pollen germination and viability. Warming effects depended on the plant type for pollen germination and viability, on study approach for nectar sugar concentration and pollen germination, and on temperature range for pollen germination and pollinator visits. Additionally, we found that pollen germination and pollinator visits significantly decreased as temperature range increased. Our results showed that global warming affects floral rewards in both wild and crop plants, providing insights into the effects of changing climatic conditions on plant-pollinator interactions and pollination services.

Climate-Smart Drip Irrigation with Fertilizer Coupling Strategies to Improve Tomato Yield, Quality, Resources Use Efficiency and Mitigate Greenhouse Gases Emissions

Background: Integrated water and fertilizer management is important for promoting the sustainable development of agriculture. Climate-smart drip irrigation with fertilizer coupling strategies plays an important role to mitigate greenhouse gas emissions, ensuring food production, and alleviating water scarcity and excessive use of fertilizers. Methods: The greenhouse experiment consists of three drip irrigation treatments which include D1: drip irrigation (100 mm); D2: drip irrigation (200 mm); D3: drip irrigation (300 mm) under three different fertilizer management practices N1: nitrogen level (150 kg N ha−1); N2: nitrogen level (300 kg N ha−1); N3: nitrogen level (450 kg N ha−1). Results: The results showed that significantly improved soil moisture contents, quality and tomato yield, while reduced (38.6%) greenhouse gas intensity (GHGI) under the D3N3 treatment. The D2 and D3 drip irrigation treatments with 450 kg nitrogen ha−1 considerably improved NH4+-N contents, and NO3−-N contents at the fruit formation stage. The improve in net primary productivity (NPP), net ecosystem productivity (NEP), evapotranspiration (ET), and ecosystem crop water productivity (CWPeco) through D3N3 treatment is higher. The D3N3 treatment improved (28.2%) the net global warming potential (GWP), but reduced GHGI, due to improved (18.4%) tomato yield. The D3N3 treatment had significantly greater irrigation water productivity (IWP) (42.8%), total soluble sugar (TSS) (32.9%), vitamin C content (VC) (39.2%), soluble sugar content (SSC) (44.2%), lycopene content (41.3%) and nitrogen use efficiency (NUE) (52.4%), as compared to D1N1 treatment. Conclusions: Therefore, in greenhouse experiments, the D3N3 may be an effective water-saving and fertilizer management approach, which can improve WUE, tomato yield, and quality while reducing the effect of global warming.

ABA Affects Distinctive Rice Caryopses Physicochemical Properties on Different Branches

Abscisic acid (ABA) plays an important regulatory role in the grain filling process, which in turn will affect the final yield and quality of rice. The ABA biosynthesis genes of OsNCED3 and degradation gene OsABA8ox3 affect the ABA content, and then further regulate the ABA signaling. During the development of rice panicle, compared with primary grains (superior grains) growing on primary branches, secondary grains (inferior grains) growing on secondary branches exhibit characteristics. However, little is reported on the physicochemical characteristics of starch between superior and inferior grains in ABA related transgenic lines. In this study, OsNCED3 and OsABA8ox3 transgenic plants were used as materials. The results showed that compared with the WT, the OsNCED3-RNAi lines on grain weight was consistent with the trend of superior and inferior grains, while the OsABA8ox3-RNAi lines affected superior or inferior grains. The total starch and soluble sugar content of grains decreased in both OsNCED3-RNAi and OsABA8ox3-RNAi lines, and the total starch content of superior and inferior grains in OsABA8ox3-RNAi lines decreased. The starch granule size distribution of all samples showed a bimodal and increased proportion of starch grains with large granule size, in which the influence on inferior grains was greater than that of superior grains, which eventually led to a significant increase in their average granule size. The apparent amylose content of inferior grains increased significantly in most lines. The swelling power of the superior grains decreased significantly, while that of the inferior grains increased significantly. Fourier analysis showed that the order degree of starch granule surface decreased in the superior grains of the RNAi line, while it increased in the inferior grains of the OsABA8ox3-RNAi line but decreased in the OsNCED3-RNAi lines. In the superior grains, the relative crystallinity of starch decreased in the OsNCED3-RNAi lines, but remained unchanged or increased in the OsABA8ox3-RNAi line. In inferior grains, the relative crystallinity of starch decreased in the ABA synthesis RNAi line, but increased in the OsABA8ox3-RNAi line. In summary, the influence of ABA on the physicochemical properties of inferior grains is greater than that of superior grains.