Higher Soluble Sugar Content Research Articles

Size Does Matter: The Influence of Bulb Size on the Phytochemical and Nutritional Profile of the Sweet Onion Landrace "Premanturska Kapula" (Allium cepa L.).

The Mediterranean area is especially rich in old, both sweet and pungent, varieties of onion. The synthesis of phytochemicals takes place concurrently with the overall development and maturation of vegetables; however, it is unclear whether there is a correlation between onion bulb size and antioxidant compound content, antioxidant capacity, and nutritional parameters and what the origin of these variations is. The aim of this work was to investigate the biochemical and nutritional aspects of the sweet onion landrace "Premanturska kapula", as well as to investigate the influence of onion bulb size on onion phytochemical and nutritional profile. The sweet onion landrace "Premanturska kapula" has a high soluble sugar content, a high antioxidant capacity, and a high phenolic compound content. Quercetin-3,4'-diglucoside and quercetin-4'-glucoside were the major flavonols, while protocatehuic acid was the major phenolic acid detected. The choice of onion bulb size can impact the profile of the sugars present, with large bulb sizes favoring higher sucrose and fructooligosaccharides content compared to small bulb sizes which were more abundant in glucose. The total sugars or bulb dry matter were not affected by bulb size. Phenolic compounds were more abundant in smaller bulb sizes, thus indicating a link between bulb development and phenolic compound allocation within the plant. This link possibly derived from agronomic practices such as bare-root transplants, or even open pollination which causes a broader genetic variability. From a consumer perspective, it can be a choice between the small and medium bulb sizes on one hand, which are more abundant in polyphenolics and simple sugars, or on the other hand, the larger bulbs which are more abundant in fructooligosaccharides known to carry excellent health benefits.

Polyphenolic and Fruit Colorimetric Analysis of Hungarian Sour Cherry Genebank Accessions

Sour cherry is one of the most important horticultural crops in the Hungarian market. Its flavour combination makes it ideal for fresh consumption as well as canned products. The Hungarian and European markets have requested for new varieties to be introduced, making the evaluation of breeding and prebreeding material a crucial point. A total of 30 sour cherry accessions from the genebank collection were investigated for their potential inclusion into the breeding program. The main aim of the study was to identify candidates for future breeding programs, selecting their colour profiling and total polyphenolic content (TPC). This study follows the antioxidant activity of cherry species by determining the total content in polyphenols. Polyphenols are found in higher concentration in cherries when compared to other plants and have been identified as free radical scavengers, which are useful to prevent the occurrence of several diseases. Furthermore, TPC has been observed as a contributor of bitterness, acidity, colour, flavour, odour, and oxidative stability. The accessions were evaluated for their colour, fruit weight, flavour profile, firmness, and TPC. Colorimetric data were compared among four methods to illustrate to the Hungarian breeders which of the available approaches is the most accurate for sour cherry breeding. Results suggested that several accessions appear relevant for the breeding program, such as ‘Pipacs 1′, ‘Bosnyák’, ‘Hortenzia Királynője’, and ‘Mogyoródi Kései’. The total polyphenolic content was highest in ‘Pipacs1′ and lowest in ‘Kántorjánosi 3′. ‘Pipacs 1′ and ‘Hortenzia Királynője’ had interestingly high acidity content and light to very light fruit colours. ‘Bosnyák’ had a deep and dark colour with high soluble sugar content. ‘Mogyoródi Kései’ appears to have the biggest fruit. All mentioned varieties will be included in future breeding programs.

Genome-Wide Identification of the RsSWEET Gene Family and Functional Analysis of RsSWEET17 in Root Growth and Development in Radish

SWEET (Sugars Will Eventually be Exported Transporter) genes play essential roles in various biological processes, including phloem loading, sugar efflux, plant development and stress response. In this study, a total of 33 RsSWEET gene members were identified in the radish genome. They could be divided into four subfamilies and are distributed on eight radish chromosomes. Cis-acting regulatory element analysis indicated that these RsSWEET genes were potentially involved in the radish growth and development and stress response process, including circadian control and light response and responses to numerous stresses, including low-temperature and drought stress. Transcriptome data analysis revealed that a number of RsSWEET genes exhibited specific expression patterns in different tissues and developmental stages of radish. Moreover, several RsSWEET genes (e.g., RsSWEET2a, RsSWEET3a, RsSWEET16b and RsSWEET17) showed differential expression profiles under various abiotic stresses, including cold, heat, salt, Cd and Pb stress. Remarkably, the RsSWEET17 was specifically expressed in the cambium of radish. RsSWEET17 was heterologously expressed in yeast strain EBY.VW4000, which suggested that it has the ability to transport sugar. Notably, RsSWEET17-overexpressing Arabidopsis plants exhibited excessive root length, greater fresh weight and higher soluble sugar content (SSC) accumulation compared with wild-type (WT) plants, indicating that RsSWEET17 might positively regulate radish taproot development by strategically manipulating sugar accumulation. Collectively, these results clarify the molecular mechanisms underlying RsSWEET-mediated sugar accumulation and root growth and development in radish.

Soybean GmVIT1 Gene Confers Plant Tolerance to Excess Fe/Mn Stress

Iron (Fe) and (Mn) are essential for the plant but are toxic when in excess. Vacuolar iron transporters (VITs) are involved in plant metal storage and detoxication. In this study, we screened two soybean cultivars (HN51 and SN37) with different responses to iron stress. From HN51 and SN37, we identified a new gene GmVIT1, for which expression is closely related to iron stress response by transcriptomic and quantitative analysis. We obtained GmVIT1 and GmVIT1 promoter from the iron deficiency-tolerant soybean variety Heinong51. Sequence analysis showed that GmVIT1 contained a conserved 170-residue VIT domain and localized at the tonoplast. Moreover, GmVIT1 is expressed in soybean leaves, stems, and roots. The expression of GmVIT1 was significantly induced by excessive Fe/Mn in leaves and stems. GUS assay showed that excess Fe/Mn enhanced GmVIT1 promoter activity. Furthermore, overexpression of GmVIT1 in Arabidopsis seedlings showed reduced phytotoxic effects induced by excess Fe/Mn stress, including yellowing in leaves, decreased chlorophyll content, and accumulated MDA. GmVIT1 overexpression in Arabidopsis showed relatively higher soluble sugar content and SOD, POD, and CAT activity. In addition, the ferric reductase activity in GmVIT1 overexpression in Arabidopsis decreased under excess Fe, while it increased under excess Mn. By integrating all these results, we found that GmVIT1 plays a vital role in plant response to excess Fe/Mn. The results showed that GmVIT1 was worthy of metal homeostasis mechanism research in plants and could be applied in the metal toxic-tolerance improvement in crops.

Rice lipid transfer protein, OsLTPL23, controls seed germination by regulating starch-sugar conversion and ABA homeostasis.

Seed germination is vital for ensuring the continuity of life in spermatophyte. High-quality seed germination usually represents good seedling establishment and plant production. Here, we identified OsLTPL23, a putative rice non-specific lipid transport protein, as an important regulator responsible for seed germination. Subcellular localization analysis confirmed that OsLTPL23 is present in the plasma membrane and nucleus. The knockout mutants of OsLTPL23 were generated by CRISPR/Cas9-mediated genome editing, and osltpl23 lines significantly germinated slower and lower than the Nipponbare (NIP). Starch and soluble sugar contents measurement showed that OsLTPL23 may have alpha-amylase inhibitor activity, and high soluble sugar content may be a causal agent for the delayed seed germination of osltpl23 mutants. Transcript profiles in the germinating seeds exhibited that the abscisic acid (ABA)-responsive genes, OsABI3 and OsABI5, and biosynthesis genes, OsNCED1, OsNCED2, OsNCED3 and OsNCED4, are obviously upregulated in the osltpl23 mutants compared to NIP plants, conversely, ABA metabolism genes OsABA8ox1, OsABA8ox2 and OsABA8ox3 are stepwise decreased. Further investigations found that osltpl23 mutants displays weakened early seedling growth, with elevated gene expresssion of ABA catabolism genes and repressive transcription response of defence-related genes OsWRKY45, OsEiN3, OsPR1a, OsPR1b and OsNPR1. Integrated analysis indicated that OsLTPL23 may exert an favorable effect on rice seed germination and early seedling growth via modulating endogenous ABA homeostasis. Collectively, our study provides important insights into the roles of OsLTPL23-mediated carbohydrate conversion and endogenous ABA pathway on seed germination and early seedling growth, which contributes to high-vigor seed production in rice breeding.

Comprehensive Evaluation of Raw Eating Quality in 81 Sweet Potato (Ipomoea batatas (L.) Lam) Varieties.

The raw eating quality of sweet potato is complex. As consumers start paying more attention to the raw eating quality of tuberous roots in sweet potato, the evaluation of the raw eating quality of sweet potato is becoming an important issue. Therefore, we measured 16 quality indicators in 81 varieties of sweet potato. It was found that these 16 quality traits had different coefficients of variation (C.V.). Among them, the C.V. of fructose, glucose, and adhesiveness were the largest: 87.95%, 87.43% and 55.09%, respectively. The cluster analysis method was used to define six categories of the different tuberous roots of sweet potato. Group I, III, and IV had a stronger hardness and higher starch and cellulose content. Groups II, V, and VI were softer, with a high moisture and soluble sugar content. The principal component analysis method was used to comprehensively evaluate 16 quality indicators of 81 sweet potato varieties. It was found that Futian1, Taishu14, and Nanshu022 are good varieties in terms of raw eating quality. These varieties have low hardness, high adhesiveness in texture, high soluble sugar content, and low starch and cellulose. Future research should focus on improving the raw eating quality of sweet potato by reducing hardness, starch, and cellulose, while increasing adhesiveness, soluble sugar, and moisture content.

Transcriptomic dissection underlying physiological and anatomical characteristics of poplar wood in response to changes in light intensity and nitrogen availability

To dissect the transcriptomic reprograming underlying the physiological and anatomical characteristics in the wood of Populus species in response to changes in light and nitrogen (N) availability, the saplings of P. alba × P. glandulosa were exposed to either control or high light intensity in combination with one of low, normal and high N levels. High light caused greater CO2 assimilation rate, higher concentrations of soluble sugars and starch, decreased enzymatic activities of NR and GS and increased activities of GOGAT and GDH, higher IAA and lower ABA, JA and SA contents, narrower fibers, and thinner thickness of fiber wall in the wood of poplars under normal N condition. Low N supply led to greater levels of sucrose and starch, lower contents of most amino acids, IAA, ABA and JA, and narrower vessels and fibers, and high N caused the opposite effects in poplar wood exposed to control light. Transcriptomic reprograming occurred underlying the physiological and anatomical changes of P. alba × P. glandulose in acclimation to high light in combination with one of low, normal and high N levels. High light- and low/high N-induced differential expression of the key genes including neutral invertases, ASN1, JAZ1, and TIP1;3, involved in the metabolism of carbohydrate, amino acids and phytohormones, and water transport, corresponded well to changes in physiological and anatomical characteristics in poplar wood in response to high light and altered N availability. These results suggest that physiological and anatomical characteristics are altered in the wood and the underlying transcriptomic reprograming is critical for the wood in acclimation to high light in combination with changing N availability.

Why is root sprouting not more common among plants? Phytohormonal clues and ecological correlates

Root sprouting (RS) species can regenerate from even small root fragments. The root buds are usually well protected against disturbance because they are deep in the soil, and injury oftentimes boosts root sprouting. Despite these obvious advantages, only 10% of plants exhibit RS ability. Are there specific ecophysiological barriers to RS ability? We set up a controlled experiment with ten congeneric pairs of herbs differing in RS ability and exposed them to severe aboveground biomass removal and assessed how RS and non-RS species differ in biomass production, root nitrogen and phosphorus content, and root tissue carbohydrate concentrations and whether phytohormone profiles explain variation in RS ability. No differences were observed in regenerated biomass three months after biomass removal, although RS species had lower root dry matter content, lower root nitrogen content, higher soluble sugar content, and a lower auxin-to-cytokinin ratio than non-RS species. RS and non-RS herbs differed in root tissue carbohydrate concentrations, which suggests that RS species, apart from having RS ability, might be better prepared for disturbance due to the availability of stored energy and carbon. Presumably, the key barrier to the more frequent occurrence of RS ability in the herbaceous plants studied here is a low auxin-to-cytokinin ratio, which is necessary to induce RS but is likely non-existent in most plants in order to avoid the risk of developmental deformities.

Corn silage, a systematic review of the quality and yield in different regions around the world

Corn sialge (Zea mays L.) is the most widely used in the world in dairy cattle diets because of its higher biomass yields, palatability, homogeneous quality at harvest, and ease of silage due to its higher soluble sugar content. Studies were systematically searched to know the silage corn quality and yield from different countries concerning dry matter yield (t/ha), population density (plant density/ha), quantity of Dry Matter (DM), Crude Protein (CP), Neutral Detergent Fiber (NDF), Non-Fibrous Carbohydrates (NFC), Organic Matter (OM), DM Digestibility (DMD), Neutral Detergent Fiber Digestibility (NDFD), and milk production (kg) per hectare (kg milk/ha) using MILK2006®. Six clusters (CL, PROC CLUSTER) of corn silage were analyzed: CL1: “Starch,” which included DMD, DNDF, TDN1 x DM, Mega calories per kg of DM, and kg of milk/t DM; CL2: “ether extract” which included TDN1 x DM, Mcal/kg DM, and kg of milk/t DM; CL3: “DM,” composed only of DNDF; CL4: “Plant Density,” including Yield of DM/ha and Milk Production/ha; CL5: “NDF,” and CL6: “CP.” In conclusion, CL1 is characterized by a higher DMD, NDFD, CNF, and starch, which allow higher TDN1 x DM and an energy concentration (Mcal/kg DM) with higher milk production (kg milk/ha). CL2 with a higher ether extract (EE) allows higher TDN1 x DM and an energy concentration (Mcal/kg DM) having a higher milk production (kg milk/ha). The DM concentration increases in the whole plant because of maturity, affecting the starch content and NDFD; the DM content (> 35 g/100 g DM) mainly causes a decrease in the NDFD, while in a very early stage of DM harvest (< 25 g/100 g DM) a low ratio of starch:NDFD is present.

Agronomic characters and commodity and consumer qualities of new varieties and hybrid forms of cherries in the conditions of Dagestan

Studied were the yield, biochemical composition, tasting and consumer quality indicators of 24 hybrid forms and 12 varieties of cherry bred by the Dagestan Breeding Experimental Station of Fruit Crops. The research was carried out using conventional methods of analysis and standard methods of cherry variety studying. Of the group of varieties of early-medium ripening, the best distinguished by a high content of soluble dry substances, sugars and vitamin C were the varieties Zhemchuzhnaya, Granatovaya, Almaznaya, Bigarro Krainskogo, Bereket, and hybrid forms 31/7; 109/1 and 180/1 in which the mass concentration of these substances ranged from 12.4-14.7 %; 10.34-12.85 % and 6.9-9.5 mg%, respectively. Among the varieties of medium ripening, the largest ability to accumulate soluble dry substances, sugars and vitamin C in fruits was shown by the varieties Bujnakskaya chernaya, Lezginka, Maral and hybrids numbered 43/2; 190/4 and 71/3 in which the content of these components of the chemical composition was 12.4-16.6 %; 10.53-12.19 % and 7.2-9.2 mg%, respectively. The best indicators of fetal weight, compared to the control variety of cherries Dagestanka (7.4 g) in the group of varieties of early-medium maturation were shown by: Zhemchuzhnaya (8.0 g); Granatovaya (8.2 g) and Bereket (8.3 g). Among the varieties of medium ripening, a more significant mass of the fruit compared to the control variety Napoleon chernaya (7.2 g) was in the varieties Maral (7.4 g) and Bujnakskaya chernaya (8.3 g). The highest overall tasting rating (4.9-5 points) was received by the fruits of the varieties Granatovaya, Bereket, Zhemchuzhnaya, Lezginka, Bujnakskaya chernaya and Maral. The same varieties had good indicators of average yield (t/ha): Granatovaya – 9.78; Bereket – 8.72; Bujnakskaya chernaya – 7.59 and Maral – 7.54. Taking into account the results of the studies carried out, it can be concluded that the varieties of cherry bred by the Dagestan Breeding Experimental Station of Fruit Crops Granatovaya, Bereket, Buinakskaya chernaya and Maral the fruits of which have the best agronomic characters and high commodity and consumer qualities, can be submitted for state variety testing and used in breeding work.

Dual effect of the presence of fruits on leaf gas exchange and water relations of olive trees.

The presence of fruits provokes significant modifications in plant water relations and leaf gas exchange. The underlying processes driving these modifications are still uncertain and likely depend on the water deficit level. Our objective was to explain and track the modification of leaf-water relations by the presence of fruits and water deficit. With this aim, net photosynthesis rate (AN), stomatal conductance (gs), leaf osmotic potential (Ψπ), leaf soluble sugars and daily changes in a variable related to leaf turgor (leaf patch pressure) were measured in olive trees with and without fruits at the same time, under well-watered (WW) and water stress (WS) conditions. Leaf gas exchange was increased by the presence of fruits, this effect being observed mainly in WW trees, likely because under severe water stress, the dominant process is the response of the plant to the water stress and the presence of fruits has less impact on the leaf gas exchange. Ψπ was also higher for WW trees with fruits than for WW trees without fruits. Moreover, leaves from trees without fruits presented higher concentrations of soluble sugars and starch than leaves from trees with fruits for both WW and WS, these differences matching those found in Ψπ. Thus, the sugar accumulation would have had a dual effect because on one hand, it decreased Ψπ, and on the other hand, it would have downregulated AN, and finally gs in WW trees. Interestingly, the modification of Ψπ by the presence of fruits affected turgor in WW trees, the change in which can be identified with leaf turgor sensors. We conclude that plant water relationships and leaf gas exchange are modified by the presence of fruits through their effect on the export of sugars from leaves to fruits. The possibility of automatically identifying the onset of sugar demand by the fruit through the use of sensors, in addition to the water stress produced by soil water deficit and atmosphere drought, could be of great help for fruit orchard management in the future.

Drip Irrigation Depth Alters Root Morphology and Architecture and Cold Resistance of Alfalfa

Combined stress from water and temperature is considered an effective approach for improving the cold resistance of alfalfa (Medicago sativa L.). However, the relationships among irrigation depth, root morphology and architecture, and cold resistance of alfalfa remain unclear. In this study, we investigated the effects of drip irrigation at the soil surface (Deep-0), at 20 cm depth (Deep-20), and at 40 cm depth (Deep-40) on root morphology and architecture and cold resistance of alfalfa. The Deep-0 treatment had the highest aboveground biomass and belowground biomass, and the root system in the Deep-40 treatment tended to a ‘herringbone’ branching type, which increases the cost of water uptake. After cold acclimation for 3 days, the cold resistance of Deep-0 was strongest, and was associated with higher soluble sugar content and fewer reactive oxygen species in the roots. Deep-40 enhanced the severity of drought stress on the crown and increased the risk of crown exposure to low-temperature stress. The results showed that Deep-0 promoted alfalfa growth and development by regulating root morphology and architecture and improving water absorption efficiency, thereby enhancing the ability of the root system to withstand low-temperature stress.

Alternating red and blue irradiation affects carbohydrate accumulation and sucrose metabolism in butterhead lettuce

• Different irradiation patterns of red (R) and blue LED light (B) including alternating, concurrent, and monochromatic modes have been conducted on lettuce and compared from the angel of growth, energetic efficiency and sugar metabolism of lettuce. • The alternating R/B modes have been proved to increase the biomass and soluble sugar accumulation in lettuce on the basis of the same daily amount of photons and electric energy consumption as the concurrent RB. • The promotion effects of alternating R/B was relevant to the alternating interval of r and B, and the alternating R/B with appropriate interval could be considered as energy efficient irradiation mode for lettuce in a plant factory with artificial light (PFAL). • The alternating R/B modes have been proved to influence the activities and gene expression of the sucrose-metabolism related enzymes in lettuce, thus affected the carbohydrate accumulation and the development of lettuce. Sucrose metabolism and carbohydrate accumulation were evaluated in butterhead lettuce cultured under alternating red light (R) and blue light (B) irradiance. The R/B treatments were respectively R/B(5 m) (i.e. R 5 min/B 5 min), R/B(10 m), R/B(15 m), R/B(30 m) and R/B(60 m). Meanwhile, concurrent R and B (RB) as well as monochromatic R (R) and monochromatic B (B) were conducted. Compared with concurrent RB, all the alternating R/B treatments increased the fresh weight (FW), dry weight (DW) and the content of pigment and soluble sugar in lettuce on the basis of the same daily photon amount and electric energy consumption. Lettuce exposed to R/B(30 m) required the least number of photons (1.82 μmol) and electricity (1.04 MJ) per gram DW produced among all the treatments, thus R/B(30 m) was the recommended lighting mode in terms of the use efficiency of photons and electricity. Relatively higher soluble sugar content and the total sweetness index (TSI), as well as lower crude fiber content were detected in lettuce subjected to R/B(60 m), which was regarded as optimal irradiation mode in terms of lettuce taste. The content of sucrose, glucose and fructose, and the activities of sucrose phosphate synthase (SPS) and sucrose synthase (SS) in the synthesis direction, as well as the gene expression level of SPS in lettuce were all enhanced by the alternating irradiation of R/B (15 m), R/B (30 m) and R/B (60 m) in comparison to the concurrent RB treatment. Moreover, higher enzyme activities in the synthetic direction of sucrose were found to be accompanied with higher soluble sugar content in lettuce subjected to R/B (30 m), R/B (60 m) and the solely R, indicating that the enzyme activities in sucrose synthetic direction seemed more related to the soluble sugar accumulation in lettuce. The results also showed that SS in lettuce leaves mainly acted on sucrose decomposition rather than synthesis. The hexose (glucose and fructose) content of lettuce subjected to R/B(60 m) basically kept the highest level among all the treatments through the whole processing period, which might be due to that lettuce exposed to R/B (60 m) owned the highest gene expression level of SS and invertase, as well as the highest enzyme activities of SS (cleavage) and invertase among all the treatments. Solely B inhibited the gene expression of sucrose metabolism-related enzymes in lettuce, and the photon use efficiency to R by lettuce was higher than to B from the angle of biomass and soluble sugar accumulation. A low intensity of B (1/9 of the R level) alternating with R improved the photon and electric use efficiency of lettuce in this study.

Festulolium plant yield, nutritive and energy value depending on its variety

The presented research is the first to study the fodder productivity, nutritive and energy value of new varieties of Festulolium of different morphotypes in the conditions of the forest-steppe of the Central Chernozem Region of Russia. In the green mass of the studied varieties crude protein content was quite low ranging from 6.2 to 9.7%, which was 1.4-2.3 times lower than required by zootechnical norms for cattle feeding. The studied varieties of Festulolium were distinguished by a rather high content of soluble sugars, which was 14.7-19.4%. The Viknel variety contained more digestible protein (68.74-76.01 g), but this value did not differ much from other varieties, in which it ranged from 64.78 to 72.47 g/kg of green mass. Among the studied varieties of Festulolium the highest yield of green mass was obtained in the second and third years of grass stand life. Productivity of the Izumrudnyi fescue-type mowing variety reached 40.31-44.09 t/ha, which was 1.3-1.9 times higher than that of ryegrass-type mowing-and-grazing varieties, the yield of which was 23.07-31.24 t/ha.

Comparative Transcriptomics and Metabolites Analysis of Two Closely Related Euphorbia Species Reveal Environmental Adaptation Mechanism and Active Ingredients Difference.

Roots of Euphorbia fischeriana and Euphorbia ebracteolata are recorded as the source plant of traditional Chinese medicine “Langdu,” containing active ingredients with anticancer and anti-AIDS activity. However, the two species have specific patterns in the graphic distribution. Compared with E. ehracteolata, E. fischeriana distributes in higher latitude and lower temperature areas and might have experienced cold stress adaptation. To reveal the molecular mechanism of environmental adaptation, RNA-seq was performed toward the roots, stems, and leaves of E. fischeriana and E. ehracteolata. A total of 6,830 pairs of putative orthologs between the two species were identified. Estimations of non-synonymous or synonymous substitution rate ratios for these orthologs indicated that 533 of the pairs may be under positive selection (Ka/Ks > 0.5). Functional enrichment analysis revealed that significant proportions of the orthologs were in the TCA cycle, fructose and mannose metabolism, starch and sucrose metabolism, fatty acid biosynthesis, and terpenoid biosynthesis providing insights into how the two closely related Euphorbia species adapted differentially to extreme environments. Consistent with the transcriptome, a higher content of soluble sugars and proline was obtained in E. fischeriana, reflecting the adaptation of plants to different environments. Additionally, 5 primary or secondary metabolites were screened as the biomarkers to distinguish the two species. Determination of 4 diterpenoids was established and performed, showing jolkinolide B as a representative component in E. fischeriana, whereas ingenol endemic to E. ebracteolate. To better study population genetics, EST-SSR markers were generated and tested in 9 species of Euphorbia. A total of 33 of the 68 pairs were screened out for producing clear fragments in at least four species, which will furthermore facilitate the studies on the genetic improvement and phylogenetics of this rapidly adapting taxon. In this study, transcriptome and metabolome analyses revealed the evolution of genes related to cold stress tolerance, biosynthesis of TCA cycle, soluble sugars, fatty acids, and amino acids, consistent with the molecular strategy that genotypes adapting to environment. The key active ingredients of the two species were quantitatively analyzed to reveal the difference in pharmacodynamic substance basis and molecular mechanism, providing insights into rational crude drug use.

Comparative transcriptomic analysis of two Cucumis melo var. saccharinus germplasms differing in fruit physical and chemical characteristics

BackgroundHami melon (Cucumis melo var. saccharinus) is a popular fruit in China because of its excellent taste, which is largely determined by its physicochemical characteristics, including flesh texture, sugar content, aroma, and nutrient composition. However, the mechanisms by which these characteristics are regulated have not yet been determined. In this study, we monitored changes in the fruits of two germplasms that differed in physicochemical characteristics throughout the fruit development period.ResultsRipe fruit of the bred variety ‘Guimi’ had significantly higher soluble sugar contents than the fruit of the common variety ‘Yaolong.’ Additionally, differences in fruit shape and color between these two germplasms were observed during development. Comparative transcriptome analysis, conducted to identify regulators and pathways underlying the observed differences at corresponding stages of development, revealed a higher number of differentially expressed genes (DEGs) in Guimi than in Yaolong. Moreover, most DEGs detected during early fruit development in Guimi were associated with cell wall biogenesis. Temporal analysis of the identified DEGs revealed similar trends in the enrichment of downregulated genes in both germplasms, although there were differences in the enrichment trends of upregulated genes. Further analyses revealed trends in differential changes in multiple genes involved in cell wall biogenesis and sugar metabolism during fruit ripening.ConclusionsWe identified several genes associated with the ripening of Hami melons, which will provide novel insights into the molecular mechanisms underlying the development of fruit characteristics in these melons.

Evaluation on the fresh eating quality of tree peony flowers

Tree peony (Paeonia suffruticosa) is an ornamental and medicinal plant in China. The fresh eating of flower petals has gradually become a new idea for further development. This study analyzed the sensory indexes, nutritional indexes and antioxidant indexes of fresh flowers of five cultivars, namely, ‘Fengdan’ (P. ostia ‘Fengdan’), ‘Xiangyu’ (P. suffruticosa ‘Xiangyu’), ‘Zhaofen’ (P. suffruticosa ‘Zhanfen’), ‘Luoyanghong’ (P. suffruticosa ‘Luoyanghong’) and ‘High Noon’ (P. ‘High Noon’), to provide a theoretical basis for eating fresh tree peony flowers. The aroma volatiles of petals mainly comprised terpenes, alcohols and alkanes. ‘Luoyanghong’ and ‘High Noon’ have brighter colors. The taste test showed that ‘Luoyanghong’, ‘High Noon’ and ‘Xiangyu’ were the most palatable. ‘High Noon’ contained the highest soluble sugar content, ‘Luoyanghong’ contained the highest starch and vitamin C (VC) levels, and ‘Zhaofen’ contained the highest soluble protein content. The contents of bioactive compounds were the highest in ‘Luoyanghong’, and superoxide dismutase (SOD) activity was the highest in ‘Xiangyu’. The petals were rich in essential amino acids, with the highest amount in ‘Xiangyu’. ‘Luoyanghong’ and ‘High Noon’ showed strong antioxidant capacity. Therefore, tree peony flowers have excellent sensory qualities, abundant nutrients and strong antioxidant activity and could be further developed as a food to be eaten fresh. The results showed that tree peony flowers had great edible potential. Flowers of red and yellow cultivars can be considered for fresh eating on the basis of the traditional consumption of white and pink tree peony flowers.

Heterologous expression of the cysteine proteinase gene VaCP17 from the cold-adapted grapevine Vitis amurensis increases cold tolerance in Arabidopsis

Cysteine proteinases (thiol) carry out diverse and critical functions in plants through their ability to hydrolyze peptide bonds in target proteins. Here, we cloned a cysteine proteinase gene designated VaCP17 from a highly cold-resistant wild Vitis amurensis accession ‘Shuangyou’, and then its potential function in cold resistance was investigated. The results showed that the CDS of VaCP17 is 1404 bp, encoding 467 amino acids, the VaCP17 protein localized to the cell membrane. Expression of CP17 was highly distinctive among different structures of ‘Shuangyou’ and the cold-sensitive Vitis vinifera cultivar ‘Red Globe’, with the highest expression in the stem of ‘Shuangyou’ and the flower of ‘Red Globe’. Arabidopsis plants constitutively expressing a VaCP17-GREEN FLUORESCENT PROTEIN fusion (35S::VaCP17-GFP) showed increased survival after transient exposure to freezing (-6 °C), and showed lower electrolyte leakage and MDA content, higher soluble sugar content and SOD, POD and CAT activities, as compared with non-transgenic Arabidopsis controls. The expression of nine cold-resistance related genes (CBF1, CBF2, CBF3, RD29A, COR15A, KIN1, NCED3, AOC1 and JAZ10) in 35S::VaCP17-GFP plants was increased under cold treatment at 4 °C, relative to control plants. Using a yeast two-hybrid system, we identified VaNAC72, VaCAM7 and VaDi19 as potential interactors of VaCP17, and their interactions were demonstrated by a bimolecular fluorescence complementation assay. In conclusion, we revealed that VaCP17 can enhance cold resistance by influencing physiology and biochemistry and the expression of cold resistance related genes under cold stress.

Influence of eight rootstocks on fruit quality of Morus multicaulis cv. ‘Zijing’ and the comprehensive evaluation of fruit quality traits

Mulberry (Morus L.) has become an important crop throughout the world due to its fruits have been industrially exploited for various commercially valuable products. Many studies on mulberry related to genetic diversity, fruit quality, and breeding programs have been carried out, but little information on mulberry rootstocks is available, especially the possibility of applying grafting to improve the fruit quality. Here, we evaluated the effects of 8 different rootstocks on the fruit quality of ‘Zijing’ mulberry. Twelve fruit quality traits were extremely different except for the fruit shape index (FSI). ‘Zijing’ on ‘Zheza 2’ had the highest fruit weight (FW) and size, as well as titratable acidity (TA), but lower levels of other compounds content except the total soluble solids content (TSS) were detected. ‘Yuesang 51’ exhibited the highest soluble sugar content (SSC), reducing sugar content (RSC), SSC/TA ratio, anthocyanin content (AC) and the lower TA. In contrast, the lowest TSS, SSC and RSC were shown in ‘Guisang 5’. Moreover, ‘Guisang 12’ exhibited the highest TSS and soluble protein content (SPC). The highest vitamin C content (VC) was observed in ‘Guisang 6’. ‘Tang 10 × Lun109’, Zhenzhubai seedlings, ‘Yuesang 11’ together with ‘Yuesang 51’ had the lowest and similar levels of TA. Most importantly, these fruit quality traits were evaluated by principal component analysis (PCA), and ‘Yuesang 51’ with good comprehensive fruit quality was screened out, followed by ‘Guisangyou 12’. Overall, these results contribute to evaluating the roles of different rootstocks on improving fruit quality of mulberry.

Volatile Flavor Profile and Sensory Properties of Vegetable Soybean.

The volatile flavor profiles and sensory properties of different vegetable soybean varieties popularized and cultivated in China for 20, 10, and 2 years (TW292, X3, and SX6, respectively) were investigated. Nutrient composition analysis revealed that TW292 had a high soluble protein and soluble sugar content but low fat content. The total free amino acid content (15.43 mg/g) and umami free amino acid content (6.08 mg/g) of SX6 were significantly higher (p < 0.05) than those of the other varieties. An electronic tongue effectively differentiated between the umami and sweetness characteristics of the vegetable soybeans. Differences in sensory evaluation results were mainly reflected in texture and taste. A total of 41 volatile compounds were identified through HS-SPME-GC-MS, and the main flavor compounds were 1-octen-3-ol, hexanal, (Z)-2-heptenal, 2-octene, nonanal, (Z)-2-decenal, and 3,5-octadien-2-one. However, the volatile composition of different vegetable soybean varieties exhibited large variability in type and relative contents. Considerable differences in nutritional, organoleptic, and aroma characteristics were found among different varieties. The results of this study will provide a good basis for the assessment and application of the major vegetable soybean varieties grown in China.