Swelling Stage Research Articles

Interactive impact of potassium and arbuscular mycorrhizal fungi on the root morphology and nutrient uptake of sweet potato (Ipomoea batatas L.).

Sweet potato is a typical "potassium (K)-favoring" food crop and strongly dependent on arbuscular mycorrhizal fungi (AMF). Recent studies show the importance of K and AMF to morphology optimization and nutrient uptake regulation of sweet potato; meanwhile, the interaction exists between K and K use efficiency (KIUE) in sweet potato. To date, only a few studies have shown that AMF can improve plant K nutrition, and whether the benefits conferred by AMF on plant are related to K remains unclear. In this study, low-KIUE genotype "N1" and high-KIUE genotype "Xu28" were used as experimental sweet potato; Funneliformis mosseae (FM) and Claroideoglomus etunicatum (CE) were used as experimental AMF. In a pot experiment, plants "N1" and "Xu28" were inoculated with FM or CE, and applied with or without K fertilizer to uncover the effects of K application and AMF inoculation on the root morphology and nutrient absorption of sweet potato during their growing period. Results demonstrated that AMF inoculation-improved root morphology of sweet potato highly relied on K application. With K application, AMF inoculation significantly increased root tip number of "N1" in the swelling stage and optimized multiple root morphological indexes (total root length, root surface area, root volume, root diameter, root branch number, and root tip number) of "Xu28" and CE had the best optimization effect on the root morphology of "Xu28". In addition, CE inoculation significantly promoted root dry matter accumulation of "Xu28" in the swelling and harvesting stages, coordinated aerial part and root growth of "Xu28", reduced the dry matter to leaf and petiole, and was beneficial to dry matter allocation to the root under conditions of K supply. Another promising finding was that CE inoculation could limit K allocation to the aboveground and promote root K accumulation of "Xu28" under the condition with K application. The above results lead to the conclusion that K and CE displayed a synergistic effect on root development and K acquisition of high-KIUE "Xu28". This study could provide a theoretical basis for more scientific application of AMF in sweet potato cultivation and will help further clarify the outcomes of plant-K-AMF interactions.

The natural abundance of stable water isotopes method may overestimate deep-layer soil water use by trees

Abstract. Stable water isotopes have been used extensively to study the water use strategy of plants in various ecosystems. In deep vadose zone (DVZ) regions, the rooting depth of trees can reach several meters to tens of meters. However, the existence of roots in deep soils does not necessarily mean the occurrence of root water uptake, which usually occurs at a particular time during the growing season. Therefore, quantifying the contribution of deep-layer soil water (DLSW) in DVZ regions using the natural abundance of stable water isotopes may not be accurate because this method assumes that trees always extract shallow- and deep-layer soil water. We propose a multi-step method for addressing this issue. First, isotopic labeling in deep layers identifies whether trees absorb DLSW and determines the soil layer depths from which trees derive their water source. Next, we calculate water sources based on the natural abundance of stable isotopes in the soil layer determined above to quantify the water use strategy of trees. We also compared the results with the natural abundance of stable water isotopes method. The 11- and 17-year-old apple trees were taken as examples for analyses on China's Loess Plateau. Isotopic labeling showed that the water uptake depth of 11-year-old apple trees reached 300 cm in the blossom and young fruit (BYF) stage and only 100 cm in the fruit swelling (FSW) stage, whereas 17-year-old trees always consumed water from the 0–320 cm soil layer. Overall, apple trees absorbed the most water from deep soils (>140 cm) during the BYF stage, and 17-year-old trees consumed more water in these layers than 11-year-old trees throughout the growing season. In addition, the natural abundance of stable water isotopes method overestimated the contribution of DLSW, especially in the 320–500 cm soil layer. Our findings highlight that determining the occurrence of root water uptake in deep soils helps to quantify the water use strategy of trees in DVZ regions.

Effects of warming, photoperiod, and nitrogen addition on the main phenological phases of Quercus mongolica

With a large artificial climate chamber, we examined the effects of warming (control, +1.5 ℃, +2.0 ℃), photoperiod (10, 14, 18 h) and nitrogen addition (0, 5, 10, 20 g N·m-2·a-1) on the main phenological phases of Quercus mongolica in Northeast China. The results showed that 1.5 and 2.0 ℃ warming significantly advanced the bud swelling stage and delayed the leaf fully coloring stage, which prolonged the growing season. The extended days increased with the increases of warming range. Photoperiod significantly affected autumn phenology (leaf coloration onset stage, leaf coloration in general stage, leaf fully coloring stage). Compared with photoperiod of 14 h, short photoperiod (10 h) significantly delayed leaf coloration onset stage by 7.0 d, and prolonged the peak of growth season. Nitrogen addition significantly advanced the bud swelling stage, bud opening stage, first leaf unfolding stage and full leaf unfolding stage. The leaf fully coloring stage was significantly delayed by 9.5 d only at the high nitrogen level of 20 g N·m-2·a-1, indicating that high nitrogen addition prolonged the growing season of Q. mongolica. The synergistic effects of warming and high nitrogen addition (20 g N·m-2·a-1) significantly delayed the leaf fully coloring stage, which prolonged leaf coloration stage, and the synergistic effects of warming and short photoperiod, the synergistic effects of nitrogen addition and short photoperiod. The synergistic effects of warming, nitrogen addition and short photoperiod all significantly delayed the leaf coloration onset stage, which relatively prolonged the peak of growing season.

Using the swelling rate calculated from the swelling index test to evaluate the influence of concrete alkali concentration and temperature on bentonite swelling properties

ABSTRACT Bentonite is used as a buffer material in the final disposal sites of high-level radioactive waste. Its expansibility is affected by cement-based materials with high pH values; however, existing studies rarely use actual cement-based materials. This study applied the swelling rate of the swelling index test to evaluate the influence of actual concrete alkali concentrations and temperatures on the swelling properties of bentonites. The results showed that when bentonite was placed in the concrete pore solutions with high pH value at 23 and 80°C, the swelling capacity was obviously reduced, whereas the low-pH concrete solution did not reduce the swelling capacity of bentonite. The number of alkali metal ions in the low-pH concrete reacting with the bentonite was 0.8–1.8% of that in the highly alkaline concrete. The temperature rise increased the swelling rate of the bentonite. The required test period of the bentonite swelling index test was short. This method observed an obvious increase in the main swelling stage, which was favorable for judging the influence of concrete alkalinity on bentonite. Thus, the swelling rate calculated from the swelling index test was appropriate for evaluating the influence of actual concrete solutions and temperature on the swelling properties of bentonite.

The sintering analysis of biomass waste ash based on the in-situ exploration and thermal chemical calculation in the gasification process

The plentiful biomass wastes are promising fossil energy alternatives to generate indispensable energy. Biomass gasification is an effective way of producing high-value-added productions and reducing CO2 emissions. However, some ash-related issues, especially ash sintering, restrict the wide utilization of biomass energies. To minimize the negative effect of the sintering problem, this work studied the ash sintering process of typical cornstalk waste ash by in-situ experimental methods, including high-temperature stage microscope (HTSM) and thermomechanical analysis (TMA). Then the thermochemical calculation was combined to clarify the sintering mechanism. The result indicated that sintering was the first step during the ash fusion process. The initial sintering temperature (624 °C) was lower than the ash deformation temperature (919 °C), which was the first characteristic temperature of ash fusion tests. The chemical reaction of the inherent ash-related components was the main reason for the appearance of the initial sintering temperature. From the element perspective, the chemical reaction of alkali and alkali earth metals (AAEMs) was mainly involved. The alkali metals tended to react with SiO2 while alkali earth metals were prone to combine with P2O5. Except for ash sintering behavior during the heating process, the TMA trace showed another two stages, swelling and melting. Massive bubbles would be generated from the inside melts at the swelling stage and cause the drastic fluctuation of the ash-melting system until the end of the melting range. Moreover, the high heating rate was beneficial for alleviating the initial sintering temperature while having a tiny influence on changing the total range of sintering and swelling zones.

Influence of Benzothiadiazole on the Amino Acids and Aroma Compositions of ‘Cabernet Gernischt’ Grapes (Vitis vinifera L.)

The application of elicitors enhances grape quality, especially the volatile compounds. There are few studies on the influence of elicitors on the aroma compositions of grapes. Additionally, studies on the amino acids and aroma profiles of ‘Cabernet Gernischt’ grapes are scant. The objective of this work was to evaluate the effect of benzothiadiazole (BTH) treatments on the amino acids and aroma profiles of ‘Cabernet Gernischt’ grapes during berry development. BTH was sprayed on berries at three different stages during grape development; the fruit set period, swelling, and veraison stages. Physicochemical parameters, amino acids, and aroma compounds of the grapes were evaluated. The results showed increased an weight and color quality of treated grapes, while the content of primary metabolites such as sugar and amino acids in treated grapes declined relative to control grapes. However, total concentrations of the various aroma classes were higher in treated grapes, except for carbonyls and terpenoids, which presented higher levels in control grapes than in BTH-treated grapes. The correlation analysis between amino acids and aroma compounds revealed positive correlations in both samples with few negative correlations in BTH samples. The odor activity values (OAVs) affirmed the floral, fruity, and fresh-green nature of ‘Cabernet Gernischt’ grapes. BTH application to ‘Cabernet Gernischt’ berries significantly influenced the compositional qualities of the grapes.

Protease enzyme based cleaner leather processing: A review

Leather processing has been a part of people's needs since the beginning of civilization. The demand for leather has constantly pushed this sector to improve processing techniques with time. Every year, about seven million tons of salted hides and skins are used for leather manufacture across the world. However, the high concentrations of chemicals used in the processing of animal skins make the sector a potential hazard to the environment. For a long time, numerous natural enzymes have been attempted to investigate in leather processing to replace chemicals, although complete chemical substitution by enzymes has yet to be done. Proteases are arguably the most extensively utilized enzymes for dehairing hides and skins. Some researchers have utilized them in soaking, rehydration , pickling, and chrome tanning. The search for new protease sources prompted researchers to focus on enzyme engineering utilizing recombinant and immobilization technology. The goal of this review is to compile the most important aspects of using proteases in leather processing as a cleaner alternative technology that will lead to a more sustainable and environmentally friendly leather industry. • Proteases minimize the use of reducing agents, acids and alkalis in leather processing. • Protease synthesis is influenced by sources, pH, temperature, ions, and solvents. • Proteases primarily act during swelling and dehairing stages of the leather processing. • Engineered proteases reduce water consumption and lower pollutant load in the leather processing. • Focus should be given to reduce enzyme manufacturing costs.

Profiling of the Candidate Interacting Proteins of SELF-PRUNING 6A (SP6A) in Solanum tuberosum

SELF-PRUNING 6A (SP6A), a homolog of FLOWERING LOCUS T (FT), has been identified as tuberigen in potato. StSP6A is a mobile signal synthesized in leaves and transmitted to the stolon through phloem, and plays multiple roles in the growth and development of potato. However, the global StSP6A protein interaction network in potato remains poorly understood. In this study, BK-StSP6A was firstly used as the bait to investigate the StSP6A interaction network by screening the yeast two-hybrid (Y2H) library of potato, resulting in the selection of 200 independent positive clones and identification of 77 interacting proteins. Then, the interaction between StSP6A and its interactors was further confirmed by the Y2H and BiFC assays, and three interactors were selected for further expression analysis. Finally, the expression pattern of Flowering Promoting Factor 1.1 (StFPF1.1), No Flowering in Short Days 1 and 2 (StNFL1 and StNFL2) was studied. The three genes were highly expressed in flowers or flower buds. StFPF1.1 exhibited an expression pattern similar to that of StSP6A at the stolon swelling stages. StPHYF-silenced plants showed up-regulated expression of StFPF1.1 and StSP6A, while expression of StNFL1 and StNFL2 was down-regulated in the stolon. The identification of these interacting proteins lays a solid foundation for further functional studies of StSP6A.

Cover cropping and chemical fertilizer seasonally mediate microbial carbon and phosphorus metabolisms in an apple orchard: Evidence from the enzymatic stoichiometry method

The extracellular enzymatic stoichiometry in soil in terms of the ratios of soil enzyme activities related to the acquisition of nutrients such as carbon (C), nitrogen (N), and phosphorus (P) can reflect the demand for resources by microorganisms. However, it is not clear how cover cropping and chemical fertilization might shift nutrient limitations for microbes in terms of the soil enzymatic stoichiometry in an apple orchard. Thus, we determined the metabolic limitations for microbes in soil based on enzymatic stoichiometry and clarified their effects on the carbon use efficiency (CUE) for soil microbes. The experiment was conducted in two main orchard plots under cover cropping and no cover cropping, where two subplots received no fertilizer or N, P, and K fertilizer application. The activities of C, N, and P acquiring enzymes (β-1,4-glucosidase, leucine aminopeptidase, β-1,4-N-acetylglucosaminidase, and acid or alkaline phosphatase), soil nutrient contents, plant nutrient contents, and microbial biomass were determined. We found that cover crop and fertilization significantly influenced the soil properties, microbial biomass, and soil enzyme activities and stoichiometry in the apple orchard, and the effects varied at different developmental stages (bud breaking, fruit swelling, and fruit maturity stages) and distances (soil samples were collected at 30, 60, 90, 120, and 150 cm from the trunks of apple trees). Soil extracellular enzymatic stoichiometry analysis showed that microbial metabolism was affected by relative P limitation in the soil throughout the growth of apple trees, but it varied among different treatments, stages, and sampling distances. Microbial carbon limitation was affected by the cover crop and fertilization at different stages and distances. Random forest analysis suggested that the soil available P and available N contents were the two most important factors that affected microbial C metabolism in the germination, fruit swelling, and mature stages. Microbial CUE was also significantly correlated with microbial P and C limitation. However, microbial C metabolism was affected by the soil available P as well as the soil C. An increase in the soil available P could have made more P available for microbial energy production and increased microbial C metabolism. Overall, our results indicate that the soil available P and available N regulated microbial C and P metabolism at different tree development stages, thereby providing insights into how microbial C and P metabolism and microbial C turnover are affected by the soil enzymatic stoichiometry in an apple orchard under cover crop and fertilization.

Influence of Gel Stage from Cellulose Dissolution in NaOH-Water System on the Performances of Cellulose Allomorphs-Based Hydrogels.

Novel hydrogels were prepared starting from different cellulose allomorphs (cellulose I, II, and III), through a swelling stage in 8.5% NaOH aqueous solution, followed by freezing at low temperature (−30 °C), for 24 h. After thawing at room temperature, the obtained gels were chemical cross-linked with epichlorohydrin (ECH), at 85 °C. The swelling degrees of the hydrogels were investigated, and a complex dependence on the type of the cellulose allomorph was found. Moreover, the gel stage has been shown to play a key role in the design of hydrogels with different performances, following the series: H-CII > H-CI > H-CIII. The correlations between the allomorph type and the morphological characteristics of hydrogels were established by scanning electron microscopy (SEM). The hydrogel H-CII showed the biggest homogeneous pores, while H-CIII had the most compacted pores network, with small interconnected pores. The rheological studies were performed in similar shear regimes, and a close correlation between the strength of the gel structure and the size of the gel fragments was observed. In the case of hydrogels, it has been shown that H-CII is softer, with a lower resistance of the hydrogel (G′) above the oscillation frequencies tested, but it maintains its stable structure, while H-CIII has the highest modulus of storage and loss compared to H-CI and H-CII, having a stronger and more rigid structure. The X-ray diffraction (XRD) method showed that the crystalline organization of each type of allomorph possesses a distinctive diffraction pattern, and, in addition, the chemically cross-linking reaction has been proved by a strong decrease of the crystallinity. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy provided clear evidence of the chemical cross-linking of cellulose allomorphs with ECH, by the alteration of the crystal structure of cellulose allomorphs and by the formation of new ether bands.

Towards an understanding of multimodal traits of female reproduction in chimpanzees

Although primates have long been regarded as microsmatic, recent studies indicate that olfaction is an important sensory mode of primate communication, e.g., in the context of reproduction. However, large gaps remain in our understanding of primate olfactory traits, especially in the great apes. Female chimpanzees (Pan troglodytes) possess an exaggerated sexual swelling, which is an imprecise signal of fertility that is thought to serve to confuse paternity. However, some high-ranking males that copulate most frequently on the days when females are most fertile seem to have more precise information on the timing of ovulation, which suggests the existence of an olfactory fertility trait. In order to examine, and provide evidence for, fertility-related chemical information in female chimpanzees, we used gas chromatography—mass spectrometry to analyze the chemical composition of female body odor collected across the menstrual cycle during various stages of sexual swelling (97 samples of six females). The chemical composition was significantly affected by swelling stage, and eight substances were detected that were strongly related to the latter. The existence of an additional, olfactory, fertility trait may help males to fine-tune their sexual behavior or allow females to strengthen concealment of the exact timing of ovulation, and needs to be further investigated in follow-up studies. The results of our study provide much-needed evidence for the existence of an olfactory cue related to reproduction in chimpanzees, and form a basis for future studies on the interplay between visual and olfactory information on female fertility.

Structural, volumetric and water retention behaviors of a compacted clay upon saline intrusion and freeze-thaw cycles

This study investigates the evolution of the structural, volumetric and water retention behaviors of a compacted clay during soaking and desiccation considering the influences of freeze-thaw (FT) cycles and saline intrusion. Compacted specimens were subjected to different FT cycles and then submerged in NaCl solution with different concentrations to facilitate the saline intrusion and measure the swelling behaviors. Shrinkage curve and filter paper tests were thereafter performed to reveal the clay's volumetric and water-retention characteristics during desiccation. Mercury intrusion porosimetry and field emission scanning electron microscopy tests were conducted to observe the evolution of the clay's microstructure. Experimental results show that the clay's micropores decrease and macropores increase after FT cycles, which is associated with the migration of water, growth of ice crystals, and development of FT-induced cracks during FT cycles. Similar observations were obtained from specimens after the saline intrusion, which is attributed to the osmotic and osmotically-induced consolidation. FT-induced cracks significantly reduce the clay's swelling and shrinkage potentials. FT cycles result in the shrinkage of micropores which leads to a reduction in the water retention capacity in the low suction range (capillary regime). The salinization suppresses the swelling of the clay and prolongs its primary and secondary swelling stages. The shrinkage potential initially increases and then decreases with increasing saline concentration. Salinization has significant influences on the osmotic suction and thus alters the clay's water-retention curves in terms of total suction. It demonstrates little impact on the clay's water-retention curves in terms of matric suction. • Studied joint effects of FT action and saline intrusion on a compacted clay. • Micropores decrease and macropores increase upon FT cycles and salinization. • Swelling and shrinkage potentials reduce after FT cycles and saline intrusion. • Salinity and FT mainly affect adsorptive and capillary effects, respectively.

Perkecambahan Asimbiotik Biji Anggrek Dendrobium bicaudatum pada Media dengan Penambahan Ekstrak Tomat secara In Vitro

Asymbiotic Germination of Dendrobium bicaudatum Orchid Seeds on Media with In Vitro Addition of Tomato Extract. Dendrobium bicaudatum is a natural orchid that needs to be preserved. Orchid seeds propagation naturally (symbiotic) has a low success rate. Orchid seeds do not have an endosperm. Asymbiotic germination with in vitro culture techniques can be an alternative solution for the propagation of orchid seeds. This study aimed to determine the effect of giving tomato extract on modified media on the asymbiotic germination of Dendrobium bicaudatum orchid seeds. This research used the Completely Randomized Design with five treatments of tomato extract concentration, namely 0%, 5%, 10%, 15%, 20%, with 4 replications. The variables observed in this study were the time and percentage of phase 1; time and percentage of phase 2; time and percentage of phase 3; time and percentage of phase 4; time and percentage of phase 5; and time and percentage of phase 6. The results showed that the tomato extract treatment had a significant or very significant effect on the germination of Dendrobium bicaudatum orchid seeds and the best treatment for the fastest and the highest percentage of germination from protocorm to First Leaf Primodium was the addition of tomato extract with a concentration of 15% or 20%, and a concentration of 0% tomato extract for the early stages of swelling of the embryo.

Molecular Dynamics Simulation of Nanoscale Elastic Properties of Hydrated Na-, Cs-, and Ca-Montmorillonite

The knowledge of nanoscale mechanical properties of montmorillonite (MMT) with various compensation cations upon hydration is essential for many environmental engineering-related applications. This paper uses a Molecular Dynamics (MD) method to simulate nanoscale elastic properties of hydrated Na-, Cs-, and Ca-MMT with unconstrained system atoms. The variation of basal spacing of MMT shows step characteristics in the initial crystalline swelling stage followed by an approximately linear change in the subsequent osmotic swelling stage as the increasing of interlayer water content. The water content of MMT in the thermodynamic stable-state conditions during hydration is determined by comparing the immersion energy and hydration energy. Under this stable hydration state, the nanoscale elastic properties are further simulated by the constant strain method. Since the non-bonding strength between MMT lamellae is much lower than the boning strength within the mineral structure, the in-plane and out-of-plane strength of MMT has strong anisotropy. Simulated results including the stiffness tensor and linear elastic constants based on the assumption of orthotropic symmetry are all in good agreement with results from the literature. Furthermore, the out-of-plane stiffness tensor components of C33, C44, and C55 all fluctuate with the increase of interlayer water content, which is related to the formation of interlayer H-bonds and atom-free volume ratio. The in-plane stiffness tensor components C11, C22, and C12 decrease nonlinearly with the increase of water content, and these components are mainly controlled by the bonding strength of mineral atoms and the geometry of the hydrated MMT system. Young’s modulus in all three directions exhibits a nonlinear decrease with increasing water content.

Femtosecond laser–assisted descemetorhexis for Descemet membrane endothelial keratoplasty: cell-based and tissue-based ex vivo analysis of precision and safety

To analyze precision and safety of femtosecond laser-assisted descemetorhexis and postoperative corneal wound healing in human ex vivo specimens. Department of Ophthalmology, University Hospital, LMU Munich, Munich, Germany. Experimental ex vivo study. 4 donor corneas underwent femtosecond laser-assisted descemetorhexis. The descemetorhexis was performed using the LDV Z8 femtosecond laser, followed by live/dead staining, phase contrast microscopy, and scanning electron microscopy. The descemetorhexis parameters were set using a modified optical coherence tomography image capturing of 8 segments within a focus of 100 μm at the posterior corneal stroma (reversed capsulotomy program). Live/dead sample staining analysis demonstrated that the femtosecond laser had minimal impact on the vitality of surrounding endothelial cells. Phase contrast microscopy and scanning electron microscopy evaluation showed that the laser produced precise, clear-cut edges, leaving no stromal tissue bridges. Femtosecond laser-assisted descemetorhexis could serve as a safe and precise technique with only minimal endothelial cell damage. To minimize stromal damage, further laser energy profile adjustments are necessary to optimize corneal treatment within different stages of corneal tissue swelling.

Defining Swelling Kinetics in Block Copolymer Thin Films: The Critical Role of Temperature and Vapour Pressure Ramp.

We studied the kinetics of swelling in high-χ lamellar-forming poly(styrene)-block- poly(lactic acid) (PS-b-PLA) block copolymer (BCP) by varying the heating rate and monitoring the solvent vapour pressure and the substrate temperature in situ during solvo-thermal vapour annealing (STVA) in an oven, and analysing the resulting morphology. Our results demonstrate that there is not only a solvent vapour pressure threshold (120 kPa), but also that the rate of reaching this pressure threshold has a significant effect on the microphase separation and the resulting morphologies. To study the heating rate effect, identical films were annealed in a tetrahydrofuran (THF) vapour environment under three different ramp regimes, low ), medium and high , for 60, 90 and 120 min, respectively, while the solvent vapour pressure and the substrate temperature were measured in real time. The translational order improved significantly with increasing the heating rate. The solvent mass uptake calculated for the different ramp regimes during annealing is linearly proportional to time, indicating that the swelling kinetics followed Case II diffusion. Two stages of the swelling behaviour were observed: (i) diffusion at the initial stages of swelling and (ii) stress relaxation, controlled at later stages. Films with a faster rate of increase in vapour pressure ) reached the pressure threshold value at an early stage of the swelling and attained a good phase separation. According to our results, highly ordered patterns are only obtained when the volume fraction of the solvent exceeds the polymer volume fraction, i.e., , during the swelling process, and below this threshold value , the films did not obtain a good structural order, even at longer annealing times.

Adapting Root Distribution and Improving Water Use Efficiency via Drip Irrigation in a Jujube (Zizyphus jujube Mill.) Orchard after Long-Term Flood Irrigation

Jujube tree yields in dryland saline soils are restricted by water shortages and soil salinity. Converting traditional flood irrigation to drip irrigation would solve water deficit and salt stress. The root distribution reacts primarily to the availability of water and nutrients. However, there is little information about the response of jujube roots to the change from flood irrigation to drip irrigation. In this context, a two–year experiment was carried out to reveal the effects of the change from long–term flood irrigation to drip irrigation on soil water, root distribution, fruit yield, and water use efficiency (WUE) of jujube trees. In this study, drip irrigation amounts were designed with three levels, i.e., 880 mm (W1), 660 mm (W2), 440 mm (W3), and the flood irrigation of 1100 mm was designed as the control (CK). The results showed that replacing flood irrigation with drip irrigation significantly altered soil water distribution and increased soil moisture in the topsoil (0–40 cm). In the drip irrigation treatments with high levels, soil water storage in the 0–60 cm soil layer at the flowering and fruit setting, and fruit swelling stages of jujube trees increased significantly compared with the flood irrigation. After two consecutive years of drip irrigation, the treatments with higher irrigation levels increased root length density (RLD) in 0–60 cm soil depth but decreased that in the 60–100 cm depth. In the horizontal direction, higher irrigation levels increased RLD in the distance of 0–50 cm, while reducing RLD in the distance of 50–100 cm. However, the opposite conclusion was obtained in W3 treatment. Additionally, in the second year of drip irrigation, W2 treatment (660 mm) significantly improved yield and WUE, with an increasing of 7.6% for yield and 60.3% for WUE compared to the flood irrigation. In summary, converting flood irrigation to drip irrigation is useful in regulating root distribution and improving WUE, which would be a promising method in jujube cultivation in arid regions.

Penicillium roqueforti conidia induced by L-amino acids can germinate without detectable swelling.

Penicillium roqueforti is used for the production of blue-veined cheeses but is a spoilage fungus as well. It reproduces asexually by forming conidia. Germination of these spores can start the spoilage process of food. Germination is typically characterized by the processes of activation, swelling and germ tube formation. Here, we studied nutrient requirements for germination of P. roqueforti conidia. To this end, > 300 conidia per condition were monitored in time using an oCelloScope imager and an asymmetric model was used to describe the germination process. Spores were incubated for 72h in NaNO3, Na2HPO4/NaH2PO4, MgSO4 and KCl with 10mM glucose or 10mM of 1 out of the 20 proteogenic amino acids. In the case of glucose, the maximum number of spores (Pmax) that had formed germ tubes was 12.7%, while time needed to reach 0.5 Pmax (τ) was about 14h. Arginine and alanine were the most inducing amino acids with a Pmax of germ tube formation of 21% and 13%, respectively, and a τ of up to 33.5h. Contrary to the typical stages of germination of fungal conidia, data show that P. roqueforti conidia can start forming germ tubes without a detectable swelling stage.

The mineral transformation and molten behaviors of biomass waste ashes in gasification-melting process

Understanding the various ash transformation properties is vital for improving gasification behavior and optimizing industrial operation conditions during the gasification-melting process of biomass wastes. In this work, five typical biomass wastes were selected to investigate the slag property. The ash fusion process, mineral transformation and AAEMs solidification behaviors were performed and predicted by mineral transformation analysis and thermochemical calculation. The results indicated that ash fusion process contained sintering, swelling, bubbling and melting stages, which was related to ash chemical compositions. Besides, the ash flow temperature had a linear relationship with the basic-to-acid ratio of biomass waste ashes. High SiO2 content would lead to strong mineral crystallinity at high temperatures. The mineral transformation was also highly related to ash compositions. The complicated reactions of inorganic matters occurred when SiO2 content lied between 50 wt% and 70 wt%. For AAEMs solidification, the alkali was prone to react simultaneously with both SiO2 and Al2O3 to form eutectoid, and the range of 35–65 wt% for SiO2 + Al2O3 contents was beneficial for alkali solidification. All the obtained data was meaningful to provide a modifying reference for the efficient and clean utilization of various biomass wastes during gasification process.

Mechanisms underlying nitrous oxide emissions and nitrogen leaching from potato fields under drip irrigation and furrow irrigation

Irrigation methods can affect nitrogen loss in agricultural soil. Exploring the effects of different irrigation methods on soil nitrogen losses in arid areas can provide a basis for more effective water and fertilizer management. A 2-year field experiment was performed, using a static chamber and soil solution extractor, to quantify nitrous oxide (N2O) emissions and nitrogen leaching from upland soils during various potato plant growth stages. The treatments included drip fertigation without fertilizer, drip fertigation + 500 kg N /hm2, drip fertigation + 1000 kg N /hm2, furrow irrigation without fertilizer, furrow irrigation + 500 kg N /hm2, and furrow irrigation + 1000 kg N /hm2. N2O emissions and nitrogen leaching were significantly different at the different potato growth stages (P＜0.01). Under both irrigation methods, the peak N2O emissions appeared during the tuber setting and swelling stages, and the total emission ratios of the two stages under each treatment in these two periods were 56–89% in 2018 and 2019. Nitrogen dioxide (NO2−) plays a crucial role in N2O emissions. A significant peak in N2O emissions was found to be related to the existence of NO2−. The correlation coefficient between NO2− concentration and N2O emissions reached 0.6413 (P＜0.05). Leaching losses also peaked during the tuber setting and swelling stages, with ratios of 51.14–84.22%. Compared with furrow irrigation, the N2O emissions from drip irrigation were decreased by 34.10–81.36%, nitrogen leaching decreased by 35.26–68.35%, and the N2O emission intensity decreased by 40.0–86.9%. Drip irrigation can effectively decrease nitrogen losses, and is an effective strategy to save water, to mitigate the emission of atmospheric pollutants such as N2O, and reduce nitrogen leaching.