Soluble Starch Contents Research Articles

Distinct morphophysiological responses of the native C4 grasses Axonopus siccus and Eragrostis polytricha to shading

Light, an important abiotic factor that shapes plant growth, is explored here in its impact on two native C4 grasses of campo rupestre, an important and unique montane ecoregion in Brazil that occurs across the biomes Cerrado, Atlantic Forest and Caatinga. Axonopus siccus and Eragrostis polytricha seedlings were subjected to two light conditions: (i) artificial shading and (ii) full sun. The evaluations included growth, nutrition, photosynthesis, leaf anatomy, and metabolism. Shading influenced most of the growth parameters of E. polytricha but left A. siccus morphology almost unchanged. The parameters of leaf anatomy, nutrient content, and chlorophyll a fluorescence exhibited consistent patterns between species. In particular, A. siccus showed higher Amax and light compensation point in shaded conditions, while E. polytricha revealed distinctive changes in carbon metabolism (soluble sugars, sucrose, and starch content), explaining its increased shade growth. These findings underscore various light stress responses in these native C4 grasses.

Rootstock affects phytotechnical attributes, gas exchange, and carbohydrate accumulation in mango scion

ABSTRACT The market demand for grafted mango seedlings is increasing because they provide uniformity and precocity for orchards and gain in productive performance. However, studies on suitable rootstocks for mango seedling production of the main mango cultivars of economic interest in the Sao Francisco Valley, Brazil, are incipient. In this context, the objective of the present study was to evaluate growth, gas exchange, and carbohydrate accumulation in the 'Palmer', 'Tommy Atkins', 'Kent', and 'Keitt' mango scions grafted onto polyembryonic rootstocks ('Capucho', 'Coquinho', and 'Espada'). The experiment was carried out under nursery conditions, with 50% shading. A randomized block experimental design was used, in a 3 × 4 factorial arrangement, consisting of three mango rootstocks ('Espada', 'Capucho', and 'Coquinho') and four mango scion cultivars ('Palmer', 'Keitt', 'Kent', and 'Tommy Atkins'), with five replications and five plants per plot. Graft success was evaluated 28 days after grafting (DAG) to determine the effects of the rootstocks on each scion. Growth, photosynthetic parameters, and total soluble carbohydrate (TSC) and starch content were evaluated 227 DAG. The rootstocks used affected the growth, photosynthetic pigments, contents of TSC and starch, and gas exchange of the mango scions. The higher graft success percentages were found for the cultivars 'Keitt', 'Palmer', and 'Kent' grafted on 'Espada' rootstocks. The cultivar 'Tommy Atkins' showed the highest graft success percentages when grafted on 'Espada' and 'Capucho' rootstocks. 'Capucho' rootstocks showed higher performance for most of the analysed variables, mainly when using 'Palmer' and 'Tommy Atkins' cultivars as scions.

The Effect of Nitrogen and Potassium Interaction on the Leaf Physiological Characteristics, Yield, and Quality of Sweet Potato

This study selected two sweet potato varieties as research subjects and conducted a field experiment using a two-factor design with two potassium (K) levels (K0 and K1) and five nitrogen (N) levels (N0–N4). The physiological changes in sweet potato leaves under different N and K treatments were measured, and nutrients such as the soluble sugar, protein, and starch content of sweet potato roots were analyzed. The results indicate that the activity of glutamine synthetase (GS) and the soluble protein content in sweet potato leaves increase first and then decrease with increasing N application, while K application can significantly increase the activity of GS and the soluble protein content. The N metabolic capacity of leaves is strongest when the fertilizer ratio is K1N2. The SPAD value of sweet potato leaves increases with increasing N application. The net photosynthetic rate, stomatal conductance, and intercellular CO2 concentration first increase and then decrease with increasing N application. K fertilizer has a significant effect on these parameters. As the N application rate increases, the starch and protein content in the tubers increase, while the soluble sugar content decreases. However, the number of tubers per plant, fresh weight of the tubers, and dry weight of the tubers increase initially and then decrease, while the vine length continuously increases. The application of K fertilizer can significantly increase the number of tubers per plant and stem thickness of sweet potato. In conclusion, the appropriate N–K combined application can promote N metabolism, enhance the photosynthetic capacity of sweet potato, increase yield, and improve quality.

Integrated cytological, physiological, and comparative transcriptome profiling reveals the regulatory network for male sterility in Welsh onion (Allium fistulosum L.)

Welsh onion (Allium fistulosum L.) is a specialty crop with value as a vegetable, condiment, and medicine. However, the molecular mechanisms related to pollen abortion and cytoplasmic male sterility are poorly understood, limiting the heterosis utilization and hybrid production of A. fistulosum. This study investigated the dynamic differences between male-sterile (MS) plants and male-fertile (MF) plants at different anther developmental stages based on integrated cytological, physiological, and transcriptomic analyses. Cytological observations revealed that pollen abortion in the MS plants began during the tetrad stage and was caused by vacuolated microspores, abnormal degradation of the tapetum, and inadequate nutrient supply. The physiological results showed that MS plants exhibited low total soluble sugar and starch contents and decreased antioxidant enzyme activities (peroxidase and catalase). Comparative transcriptome analysis identified 7005 differentially expressed genes (DEGs) and functional enrichment analysis indicated that significant transcriptomic differences were related to oxidative phosphorylation, starch and sucrose metabolism, and cutin, suberine, and wax biosynthesis. The relative expression levels of key DEGs in these three important metabolic pathways were determined using quantitative real-time polymerase chain reaction. On this basis, a core transcriptome-mediated MS network was proposed for MS plants with four functional components: inhibited sucrose synthesis and transport; blocked cutin, suberine, and wax synthesis; accelerated reactive oxygen species generation; and abnormal tapetal programmed cell death. These results provide theoretical guidance for further exploring the molecular mechanisms of male sterility in A. fistulosum.

Salicylic acid inhibition on browning of fresh-cut taro by regulating phenolic compounds and active oxygen metabolism

Surface browning of fresh-cut taro limits storage shelf-life and affects customer satisfaction. This study investigated the effects of salicylic acid (SA) on the browning of fresh-cut taro and explored the possible mechanism of SA in inhibiting browning. A 10 mmol/L SA treatment effectively delayed browning, improved soluble starch content, and reduced weight loss. Furthermore, by regulating the activities of phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO), SA treatment reduced the contents of total phenol, flavonoid, soluble quinone, and monomer phenolic acid, indicating that it inhibited phenol metabolism, decreased the synthesis of colored secondary metabolites, and suppressed surface browning in fresh-cut taro. On the other hand, SA treatment enhanced the activities of peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD), reduced lipoxygenase (LOX) activity, enhanced ascorbic acid (AsA) and glutathione (GSH) levels. It decreased malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide anion radicals (O2−·) production, indicating reduced oxidative damage. Thus, SA treatment improved the antioxidant system, reduced the accumulation of reactive oxygen species, and delayed phenolic oxidation, effectively inhibiting browning. These findings reveal SA as a feasible method for preserving fresh-cut fruits and vegetables.

Foliar application of agrochemicals enhance growth, productivity, quality and biochemical traits of soybean

Flower drop, senescence of flowers and inadequate pod filling pose significant challenges in soybean cultivation as rapid nutrient extraction from leaves during the reproductive stage accelerates leaf aging. The present study assessed the effect of foliar application of agrochemicals on growth, productivity, quality and biochemical traits of soybean at two locations during kharif (rainy) season of 2021 and 2022. The experiment comprised of ten treatments of foliar application of agrochemicals [absolute control, water spray, potassium nitrate (KNO3) 1.5%, NPK (19:19:19) 1.5%, boron 0.3%, ammonium molybdate (AM) 0.5%, thiourea 750 parts per million (ppm), urea 2.0%, muriate of potash (MOP) 0.5% and salicylic acid (SA) 100 ppm] at flower and pod initiation stages along with the recommended dose of fertilizer (RDF) in a randomized complete block design replicated thrice. Results revealed that foliar application of boron 0.3%, urea 2.0% and MOP 0.5% at Ludhiana and MOP 0.5%, potassium nitrate 1.5% and urea 2.0% at Ballowal Saunkhri increased growth (plant height and dry matter accumulation), yield attributes (number of pods plant−1, number of filled pods plant−1 and 100-seed weight) and seed yield. These agrochemicals showed positive effects on the biochemical parameters with increased levels of proline and total phenol content as well as improvements in total soluble sugars, starch and protein content. The findings suggest that foliar application of agrochemicals (boron 0.3%, urea 2.0%, MOP 0.5% and potassium nitrate 1.5%) along with RDF can improve soybean growth and seed yield by mitigating the nutrient stress at reproductive stages.

Detection and Analysis of Quality Traits of Different Black Rice Varieties in the Southern Henan Rice Region

Using 14 black rice varieties imported from Southern Henan as experimental materials, the appearance quality, grinding quality, nutritional quality, cooking and eating quality of grain in Southern Henan were tested and analyzed by means of rice huller, rice mopping machine and near-infrared grain analyzer, combined with biochemical and physical analysis techniques. The results showed that there were abundant variation types in grain length, grain width, length-to-width ratio, brown rice rate, milled rice rate, head rice rate, soluble protein content, starch content, gelatinization temperature, gel consistency and viscosity of black rice. Particularly, grain type, starch content, gelatinization temperature, viscosity and other important quality traits in black rice materials have a large variation range. Therefore, our results provide important clues for developing new high-quality varieties of black rice.

Starch and sucrose metabolism plays an important role in the stem development in Medicago sativa.

The forage quality of alfalfa (Medicago sativa ) stems is greater than the leaves. Sucrose hydrolysis provides energy for stem development, with starch being enzymatically converted into sucrose to maintain energy homeostasis. To understand the physiological and molecular networks controlling stem development, morphological characteristics and transcriptome profiles in the stems of two alfalfa cultivars (Zhungeer and WL168) were investigated. Based on transcriptome data, we analysed starch and sugar contents, and enzyme activity related to starch-sugar interconversion. Zhungeer stems were shorter and sturdier than WL168, resulting in significantly higher mechanical strength. Transcriptome analysis showed that starch and sucrose metabolism were significant enriched in the differentially expressed genes of stems development in both cultivars. Genes encoding INV , bglX , HK , TPS and glgC downregulated with the development of stems, while the gene encoding was AMY upregulated. Weighted gene co-expression network analysis revealed that the gene encoding glgC was pivotal in determining the variations in starch and sucrose contents between the two cultivars. Soluble carbohydrate, sucrose, and starch content of WL168 were higher than Zhungeer. Enzyme activities related to sucrose synthesis and hydrolysis (INV, bglX, HK, TPS) showed a downward trend. The change trend of enzyme activity was consistent with gene expression. WL168 stems had higher carbohydrate content than Zhungeer, which accounted for more rapid growth and taller plants. WL168 formed hollow stems were formed during rapid growth, which may be related to the redistribution of carbohydrates in the pith tissue. These results indicated that starch and sucrose metabolism play important roles in the stem development in alfalfa.

Physiological responses to drought stress of three pine species and comparative transcriptome analysis of Pinus yunnanensis var. pygmaea

Drought stress can significantly affect plant growth, development, and yield. Fewer comparative studies have been conducted between different species of pines, particularly involving Pinus yunnanensis var. pygmaea (P. pygmaea). In this study, the physiological indices, photosynthetic pigment and related antioxidant enzyme changes in needles from P. pygmaea, P. elliottii and P. massoniana under drought at 0, 7, 14, 21, 28 and 35 d, as well as 7 days after rehydration, were measured. The PacBio single-molecule real-time (SMRT) and Illumina RNA sequencing were used to uncover the gene expression differences in P. pygmaea under drought and rehydration conditions. The results showed that the total antioxidant capacity (TAOC) of P. pygmaea was significantly higher than P. massoniana and P. elliottii. TAOC showed a continuous increase trend across all species. Soluble sugar (SS), starch content and non-structural carbohydrate (NSC) of all three pines displayed a "W" pattern, declining initially, increasing, and then decreasing again. P. pygmaea exhibits stronger drought tolerance and greater recovery ability under prolonged drought conditions. Through the PacBio SMRT-seq, a total of 50,979 high-quality transcripts were generated, and 6,521 SSR and 5,561 long non-coding RNAs (LncRNAs) were identified. A total of 2310, 1849, 5271, 5947, 7710, and 6854 differentially expressed genes (DEGs) were identified compared to the control (Pp0D) in six pair-wise comparisons of treatment versus control. bHLH, NAC, ERF, MYB_related, C3H transcription factors (TFs) play an important role in drought tolerance of P. pygmaea. KEGG enrichment analysis and Gene set enrichment analysis (GSEA) analysis showed that P. pygmaea may respond to drought by enhancing metabolic processes such as ABA signaling pathway, alpha-linolenic acid. Weighted gene co-expression network analysis (WGCNA) revealed GST, CAT, LEC14B, SEC23 were associated with antioxidant enzyme activity and TAOC. This study provides a basis for further research on drought tolerance differences among coniferous species.

Non-destructive Prediction of Quality Parameters in Alphonso Mangoes Using Near-infrared Spectroscopy: A Comprehensive Study on Physicochemical Characteristics and Ripening Dynamics

This study focuses on the application of Near-Infrared Spectroscopy (NIRS) to predict key quality parameters in Alphonso mangoes, namely Total Soluble Solids (TSS), Titratable Acidity (TA), pulp firmness, and carotenoid content. Alphonso mangoes, known as the "king of fruits," are a significant tropical fruit, with India being the leading global producer. Quality control is crucial for fruit export, and the mango supply chain involves various procedures. Physiological transformations occur in mangoes from production to consumption, affecting their internal quality. The challenges in assessing internal quality factors such as soluble solids, dry matter, firmness, starch, and sugar content hinder the exportation of mangoes. The ripening process in mangoes involves metabolic changes leading to modifications in physical, mechanical, and chemical attributes. Non-destructive identification of internal defects in Alphonso mangoes is an underexplored field, with limited research on internal quality factors. The study aims to enhance understanding of light penetration into fruit tissues using numerical simulation techniques. NIR spectroscopy's significance in post-harvest technology is highlighted, and the study develops prediction models for quality parameters using Partial Least Squares (PLS) regression. The calibration models are optimized with spectral pre-processing techniques, and the Savitzky–Golay first derivative method yields favorable results. The results indicate changes in TSS, carotenoid content, firmness, and acidity during storage, providing insights into mango ripening dynamics. The Unscrambler software is employed for multivariate analysis, emphasizing the importance of the 600–1000 nm wavelength range. The study contributes to the development of portable instruments for rapid and accurate quality prediction of Alphonso mangoes in the supply chain.

Effects of rainfall patterns in dry and rainy seasons on the biomass, ecostoichiometric characteristics, and NSC content of Fraxinus malacophylla seedlings.

With global climate change and rising temperatures, rainfall will change. The impact of global rainfall changes on ecosystems has prompted people to delve deeper into how changes in rainfall affect plant growth; Plant biomass, nutrient element content, and non-structural carbohydrate content are very sensitive to changes in precipitation. Therefore, understanding the impact of rainfall changes on seedlings is crucial. However, it is currently unclear how the seedlings of Fraxinus malacophylla Hemsl in rocky desertification areas respond to changes in rainfall. In this study, the response of biomass, nutrient accumulation, and NSC content of Fraxinus malacophylla Hemsl seedlings to different rainfall intervals and rainfall during the dry and rainy seasons was studied. Use natural rainfall duration of 5 days (T) and extended rainfall duration of 10 days(T+) as rainfall intervals; average monthly rainfall was used as the control (W), with a corresponding 40% increase in rainfall (W+) and a 40% decrease in rainfall (W-) as rainfall treatments. The research results indicate that the biomass of roots, stems, and leaves, as well as the accumulation of C, N, and P in Fraxinus malacophylla Hemsl seedlings increase with the increase of rainfall, while the soluble sugar and starch content show a pattern of first increasing and then decreasing. The biomass and nutrient accumulation of each organ showed root>leaf>stem. Except for the beginning of the dry season, prolonging the duration of rainfall in other periods inhibits the biomass accumulation of Fraxinus malacophylla Hemsl seedlings, and promotes the accumulation of C, N, and P nutrients and an increase in soluble sugar and starch content. There was a significant positive correlation (P<0.05) between the nutrient contents of C, N, and P in various organs, as well as between soluble sugar and starch content; And N: P>16, plant growth is limited by P element. These results indicate that changes in rainfall can affect the growth and development of Fraxinus malacophylla Hemsl seedlings, increasing rainfall can promote biomass and nutrient accumulation of Fraxinus malacophylla Hemsl seedlings, and prolonging rainfall intervals and reducing rainfall have inhibitory effects on them. The exploration of the adaptation of Fraxinus malacophylla Hemsl seedlings to rainfall patterns has promoted a basic understanding of the impact of rainfall changes on the growth of Fraxinus malacophylla Hemsl. This provides a theoretical basis for understanding how Fraxinus malacophylla Hemsl can grow better under rainfall changes and for future management of Fraxinus malacophylla Hemsl artificial forests in rocky desertification areas.

Wide-characterization of high and low dry matter kiwifruit through spatiotemporal multi-omic approach

Despite the widespread use of dry matter content (DMC) as an indicator of kiwifruit quality, the physiological and molecular impact of DMC in fruit ripening remains unknown. Herein, the post-harvest physiological, metabolomic, and transcriptomic influence of DMC status on the pericarp and placenta tissue of ‘Hayward’ kiwifruit at harvest and at the onset of post-cold ripening was investigated. A segregation strategy based on DMC in commercially harvested kiwifruit was achieved with near-infrared spectroscopy for the estimation of DMC in individual fruits. Additionally, kiwifruits with distinct DMC levels were treated with 1-methylcyclopropene (1-MCP) and systematically monitored for ripening changes (20°C) at various intervals after cold storage (0°C). Following 90 and 120 days of cold exposure, high DMC kiwifruit generally exhibited superior physiological characteristics, such as increased pericarp and placenta firmness, and soluble solid and starch contents compared to low DMC kiwifruit, regardless of the 1-MCP application. Evidence is also presented for 1-MCP delaying the ripening of low-DMC fruit to the level of the untreated high-DMC kiwifruit. An accumulation of primary metabolites, particularly sugars and polyphenolic compounds, such as catechin, chlorogenic acid and procyanidin B1/B2 was evidenced in the high DMC group. At harvest, gene expression analysis revealed minor differences between DMC groups, with beta-amylase being the highest up-regulated gene in high DMC kiwifruit. Moreover, the gene expression patterns between DMC groups became more distinct after cold storage. Genes related to starch biosynthesis (i.e., glucose-1-phosphate adenyltransferase), water movement (i.e., aquaporin), polyphenolic biosynthesis (i.e., chalcone synthase) and lipid metabolism (i.e., diacylglycerol acyltransferase) showed strong variations between low and high DMC. Interestingly, the placenta tissue displayed almost 4 times more than DMC-affected differentially expressed genes compared to the pericarp, highlighting the key role of the placenta in kiwifruit ripening, notably following 1-MCP treatment. This study provides insights into the tissue-specific ripening response between kiwifruit with distinct DMC, as well as the gene expression influenced by an interaction of 1-MCP and DMC level, thereby helping develop postharvest programs aimed at improving kiwifruit quality traits.

Insight into the promoted recrystallization and water distribution of bread by removing starch granule - surface and - associated proteins during storage

The influence of starch granule surface proteins (SGSPs) and starch granule-associated proteins (SGAPs) on bread retrogradation was investigated in a reconstituted dough system. The removal of both SGSPs and SGAPs resulted in poor bread qualities, decreasing specific volume and crumb porosity, leading to more baking loss and compact crumb structure. Particularly, removing SGSPs was effective in promoting the bread retrogradation. After 7 days of storage, the hardness of bread without SGSPs showed an increase of 353.34 g than the bread without SGAPs. Proton population and relaxation times exhibited that the absence of SGSPs significantly decreased the content of bound water from 11.51 % to 7.03 %, indicating lower water-holding capacity due to the loosen gelling structure. Compared to the control group, bread without SGSPs accelerated the starch recrystallinity by a reduction in soluble starch content, thereby increasing the retrogradation enthalpy and relative crystallinity through promoting the molecular reassociation in starch.

Agronomic, physiological and transcriptional characteristics provide insights into fatty acid biosynthesis in yellowhorn (Xanthoceras sorbifolium Bunge) during fruit ripening.

Yellowhorn (Xanthoceras sorbifolium Bunge) is an oil-bearing tree species in northern China. In this study, we used yellowhorn from Heilongjiang to analyze the morphological and physiological changes of fruit development and conducted transcriptome sequencing. The results showed that the fruit experienced relatively slow growth from fertilization to DAF20 (20days after flowering). From DAF40 to DAF60, the fruit entered an accelerated development stage, with a rapid increase in both transverse and longitudinal diameters, and the kernel contour developed completely at DAF40. From DAF60 to DAF80, the transverse and vertical diameters of the fruit developed slowly, and the overall measures remained stable until maturity. The soluble sugar, starch, and anthocyanin content gradually accumulated until reaching a peak at DAF80 and then rapidly decreased. RNA-seq analysis revealed differentially expressed genes (DEGs) in the seed coat and kernel, implying that seed components have different metabolite accumulation mechanisms. During the stages of seed kernel development, k-means clustering separated the DEGs into eight sub-classes, indicating gene expression shifts during the fruit ripening process. In subclass 8, the fatty acid biosynthesis pathway was enriched, suggesting that this class was responsible for lipid accumulation in the kernel. WGCNA revealed ten tissue-specific modules for the 12 samples among 20 modules. We identified 54 fatty acid biosynthesis pathway genes across the genome, of which 14 was quantified and confirmed by RT-qPCR. Most genes in the plastid synthesis stage showed high expression during the DAF40-DAF60 period, while genes in the endoplasmic reticulum synthesis stage showed diverse expression patterns. EVM0012847 (KCS) and EVM0002968 (HCD) showed similar high expression in the early stages and low expression in the late stages. EVM0022385 (HCD) exhibited decreased expression from DAF40 to DAF60 and then increased from DAF60 to DAF100. EVM0000575 (KCS) was increasingly expressed from DAF40 to DAF60 and then decreased from DAF60 to DAF100. Finally, we identified transcription factors (TFs) (HB-other, bHLH and ARF) that were predicted to bind to fatty acid biosynthesis pathway genes with significant correlations. These results are conducive to promoting the transcriptional regulation of lipid metabolism and the genetic improvement in terms of high lipid content of yellowhorn.

Physiological, metabolic and hormonal responses of two Pinus spp. with contrasting susceptibility to brown-spot needle blight disease.

Needle blights are serious fungal diseases affecting European natural and planted pine forests. Brown-spot needle blight (BSNB) disease, caused by the fungus Lecanosticta acicola, causes canopy defoliation and severe productivity losses, with consequences depending on host susceptibility. To gain new insights into BSNB plant-pathogen interactions, constitutive and pathogen-induced traits were assessed in two host species with differential disease susceptibility. Six-month-old Pinus radiata D. Don (susceptible) and Pinus pinea L. (more resistant) seedlings were needle inoculated with L. acicola under controlled conditions. Eighty days after inoculation, healthy-looking needles from symptomatic plants were assessed for physiological parameters and sampled for biochemical analysis. Disease progression, plant growth, leaf gas-exchanges and biochemical parameters were complemented with hormonal and untargeted primary metabolism analysis and integrated for a holistic analysis. Constitutive differences between pine species were observed. Pinus pinea presented higher stomatal conductance and transpiration rate and higher amino and organic acids, abscisic acid as well as putrescine content than P. radiata. Symptoms from BSNB disease were observed in 54.54% of P. radiata and 45.45% of P. pinea seedlings, being more pronounced and generalized in P. radiata. For both species, plant height, sub-stomatal CO2 concentration and water-use efficiency were impacted by infection. In P. radiata, total soluble sugars, starch and total flavonoids content increased after infection. No differences in hormone content after infection were observed. However, secondary metabolism was induced in P. pinea visible through total phenolics, flavonoids and putrescine accumulation. Overall, the observed results suggest that P. pinea constitutive and induced traits may function as two layers of a defence strategy which contributed to an increased BSNB resistance in comparison with P. radiata. This is the first integrative study linking plant physiological and molecular traits in Pinus-Lecanosticta acicola pathosystem, contributing to a better understanding of the underlying resistance mechanisms to BSNB disease in pines.

Characterization and safety assessment of Hydroxypropyl Musa paradisiaca starch for pharmaceutical applications

The aim of the current investigation was to produce native banana starch (NBS) and hydroxypropyl banana starch (HPBS) , assess physicochemical properties, and evaluate toxicity. NBS was modified to its propyl form with a propylene oxide solution and characterized. The physicochemical properties of NBS and HPBS met the required specifications. The amylose content of NBS was found to be 25.41% ± 0.08%. The degree of substitution and hydroxyl propyl group % were found to be 0.028 and 2.894, respectively, which were within the Food and Drug Administration’s (FDA’s) acceptable limits of 0.2% and 7%, respectively. The NBS possesses superior swelling power (26.68 ± 1.06) compared to the HPBS swelling power (15.66 ± 0.61). In terms of soluble starch content (%), HPBS displayed a higher soluble starch content percentage (69.21 ± 2.04) compared to the NBS (17.01 ± 1.06). The HPBS yielded high viscosity relative to the NBS in all the concentrations of starch solutions. The increase in the soluble starch content and viscosity of propyl starch may be attributed to the increased number of hydroxy propyl group substitutions in the HPBS. For up to 14 days of the experimental period in the acute toxicity studies, the rats showed no symptoms of toxicity or fatalities. According to the findings of the subacute toxicity studies, neither the hematological nor the biochemical analyses showed any apparent abnormalities. The study’s overall results show that HPBS were safe up to doses of 1,000 mg/kg body weight, which may be regarded as a safe dosage. The modified starch’s enhanced physicochemical properties make it suitable for industrial use, and it meets FDA-approved limits, affirming its safety as a pharmaceutical excipient.

Nitraria sibirica adapts to long-term soil water deficit by reducing photosynthesis, stimulating antioxidant systems, and accumulating osmoregulators

Amid climate change and shifts in precipitation patterns, drought conditions are expanding worldwide. Drought stress severely threatens plant growth in arid and semi-arid regions, wherein shrubs play a crucial role in maintaining ecological stability. Despite its ecological significance, studies are lacking on how Nitraria sibirica adapts to long-term drought stress. Therefore, in this study, to elucidate the mechanism of drought stress adaptation in N. sibirica, we analysed morphological, physiological, and transcriptional characteristics of plants in two soil habitats: riparian (moist) and desert (arid). The results showed that in desert soils, as soil water content decreased, leaf thickness increased, while plant height and leaf area decreased. Physiologically, photosynthesis decreased; soluble sugar, starch, proline, and hydrogen peroxide content increased significantly; while soluble proteins decreased significantly. Additionally, membrane lipid peroxidation products and antioxidant enzyme activities significantly increased under drought stress. Then, Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analysis identified 313 key genes, which were considered the most significantly enriched in the photosynthesis and photosynthetic antenna protein pathways. Further, we found that the proteins encoding photosystem II (PsbP, PsbQ, PsbR, PsbY, and Psb27), photosystem I (PsaD, PsaF, PsaG, PsaH, PsaK, and PsaO), photosynthetic electron transport (PetF), and light-trapping antenna proteins were significantly downregulated under drought stress. Taken together, these results suggest that N. sibirica adapts to long-term drought conditions by suppressing photosynthesis, activating antioxidant systems, and recruiting osmoregulators. This study provides a basis for elucidating the growth mechanisms of N. sibirica under long-term drought stress conditions.

Anatomical structure and physiological characteristics of Robinia pseudoacacia of different stand ages

Drought intensity and frequency have been increased as a result of global warming. Exploring the drought resistance mechanism of Robinia pseudoacacia plantations of different stand ages on the Loess Plateau is crucial for understanding the stability of forest productivity in the region. We investigated anatomical traits, hydraulic function, and non-structural carbohydrate content of the xylem, as well as their association, in R. pseudoacacia plantations of different stand ages in a semi-arid region. The results showed that the vessel diameter, total pit membrane area, pit membrane area, vesture area, and vestured overlap of young and middle-aged stands were larger than those of mature stands, and the pit density was significantly lower in mature stands. Hydraulic conductivity was significantly related to vessel diameter, pit membrane area, and vesture area. Hydraulic conductivities of branches in young, middle-aged, and mature stands were 2.30, 2.12, and 0.76 kg·m-1·s-1·MPa-1, respectively, with embolism values of 54.5%, 53.8%, and 45.1%. Hydraulic conductivity was significantly related to soluble sugar and starch contents. The soluble sugar contents of branches in young, middle-aged and mature stands were 4.9%, 4.2%, and 3.8%, respectively. Xylem growth capacity of R. pseudoacacia in mature stand declined, resulting in the formation of small vessels with many small pits, which reduced hydraulic conductivity while maintaining hydraulic safety, resulting in a decrease of non-structural carbohydrates content. This study revealed the drought response mechanism of R. pseudoacacia plantations with different ages, providing a scientific foundation for the management and nurturing of R. pseudoacacia plantations on the Loess Plateau.

Seasonal variation in C:N:P stoichiometry, nonstructural carbohydrates, and carbon isotopes of two coniferous pioneer tree species in subtropical China.

The characteristics of C:N:P stoichiometry, nonstructural carbohydrate (NSC) content, and C stable isotopes and their relationships affect plant responses to environmental changes and are critical to understanding the ecosystem carbon and water cycles. We investigated the water use strategies and physiological changes of two pioneer tree species (Pinus armandii and Pinus yunnanensis) in response to seasonal drought in subtropical China. The seasonal variation in needle δ13C values, C:N:P stoichiometry, and NSC contents of the two tree species were studied in 25-year-old plantation in central Yunnan Province. The needle δ13C values of both species were highest in summer. Soluble sugars, starch and NSC content of the two tree species decreased from spring to winter, while there was no significant difference in the seasonal variation of soluble sugars/starch in P. armandii needles, the maximum soluble sugars/starch in P. yunnanensis needles was in autumn. In addition, the C, N, and P contents of the needles and the C:N and C:P ratios of the two species showed different seasonal fluctuations, whereas the N:P ratio decreased with the season. The C:N:P stoichiometry and NSC content of the needles showed significant correlations, whereas the needle δ13C was weakly correlated with C:N:P stoichiometry and NSC content. Phenotypic plasticity analysis and principal component analysis revealed that the needle nutrient characteristics (NSC and P contents and N:P ratio) and needle δ13C values were critical indicators of physiological adaptation strategies of P. armandii and P. yunnanensis for coping with seasonal variation. These results increase our understanding of the water-use characteristics of the two pioneer tree species and the dynamic balance between the NSC, C, N, and P contents of the needles.

Assessment of G × E interaction and stability parameters for quality, root yield and its associating traits in ashwagandha [Withania somnifera (L.) Dunal] germplasm lines

Withania somnifera (L.) Dunal holds significant pharmaceutical and nutritional benefits. The stability and superior root yield of ashwangandha genotype is a crucial parameter for long-term development and raw material supply for pharma-industries. The impact of genotype × environment (G × E) interaction on economic traits (root yield) stability on ninety-six genotypes in four different environments was evaluated in this study. Using two models of stability analysis namely Eberhart - Russell and Additive Main Effects and Multiplicative Interaction (AMMI) analysis models, current study was focused on adaptability and phenotypic stability of ashwangandha genotypes. Field trail was conducted in a randomized complete block design with three replications. Phenotypic data were collected on eleven important traits including four commercially important traits viz total soluble sugars (TSS), starch content, withanolides content and crude fiber in the main and late-season in 2020 and 2021. Analysis of variance exhibited consistency between both models. These results depicated G × E interaction, revealing subtle variations in response to environmental conditions. Eberhart and Russell model provided valuable trait performance insights, while AMMI offered genotype and environment insights. Interestingly, Eberhart and Russell model identified Env 3 as superior while Env 4 as a challenging environment. Genotypes viz. AGP-84, AGP-16, AGP-79, AGP-95, AGP-57 and AGP-14 exhibited stability and consistent performance for root yield across environments. AMMI analysis captured 52.7 % variance in the first principal component and 26.3 % in the second. Genotypes namely AGP 18, AGP 22, and AGP 57 were found best and stabile with high mean dry root yield in both models. Env 1 stood out as the most distinct, and Env 2 was representative for selecting the best genotypes.