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• Longer shape and less flushing is the aim of pepper producer, which is achieved in the full light greenhouse with P3 and then in P5 pruning. • Pruning (P3 and P5) due to improved nutrient distribution enhanced the carotenoid accumulation. • There was not a certain pattern in Ca and N absorption by light and pruning, although it seems that P5 may be more productive, and Ca absorption was greater in full light greenhouse compare with low light. Pruning and light quality and quantity can affect the fruit load, fruit shape, nutritional value, and quality of sweet pepper. The experiment was arranged as a split-plot conducted in a randomized block design. Treatments consisted of keeping 3, 5, and 7 fruits on the bush, and having un-pruned (P3, P5, and P7 Pnon=without pruning) sweet pepper (Capsicum annuum L., cv. Lumos) with 3 replications. Two greenhouses including 14,000 for the full-light one and 6000-Lux for the low one were designed. The results showed that carotenoid biosynthesis and accumulation were highly related to light, with a significant effect in the full light greenhouse, as compared with the low one. Leaves carbohydrate content was raised in P3 and P5 for both greenhouses and this was more significant in the full light greenhouse, as compared with the low one. TSS was higher in full light with pruning (P3, P5, P7); the highest TSS in the low-light greenhouse was seen in P3. Phenol, antioxidant, vitamin C, and organic acid were higher in the full light greenhouse, as compared with the low one. Conclusively, pruning was more effective on weight after increased growth of bush in the second or third harvest. Longer shape and less flushing are favored by pepper producers. This can be achieved in the full light greenhouse with P3 and then P5 pruning. [ABSTRACT FROM AUTHOR]

• Allelochemicals are eco-friendly materials having a significant role in weed control. • In the current study, 43 compounds were identified representing 98.98% of total methanolic extract composition. • The main chemical components obtained were Palmitic acid (17.50%), Palmitoleic acid (14.32%) and Oleic acid (13.83) • This study could provide an understanding about the process of weed-weed interaction for eco-friendly weed management strategy. Allelochemicals are eco-friendly and play a significant part in weed control. In this regard, an in-vitro investigation was performed to evaluate the phytotoxic potential of Nicotiana. plumbaginifolia Viv. on Senna sophera (L.) Roxb. , Chenopodium album L., Senna tora (L.) Roxb. and Setaria viridis L. The experiment is aimed to assess the impact of leaf leachate of the allelopathic plant on the biochemical parameters (chlorophyll, carbohydrate, protein and proline content) of recipient weeds. The treatments showed a retarding effect on the biochemical events. Carbohydrate and proline content were increased in test plants whereas protein and chlorophyll content declined in comparison to the control. Aqueous leachates proved to be more suppressive than organic fractions on weeds viz; S. sophera and C. album were suppressed more as compared to S. tora and S. viridis. The GC–MS (gas chromatography–mass spectrophotometry) analysis showed the incidence of different phytochemical entities in the leaf methanolic extract of leaf of N. plumbaginifolia. Forty three compounds were identified representing 98.98% of total methanolic extract composition. The main chemical components were Palmitic acid (17.50%), Palmitoleic acid (14.32%), Oleic acid (13.83), Phytol (8.46%), Neophytadiene (5.47%) and Solasodine (4.23%). The allelopathy of the volatile allelochemicals may perform a vital part in inhibiting the competitive ability of weed species and be one of the alternatives to control weed infestation. [ABSTRACT FROM AUTHOR]

Little is known about postprandial release of serum ghrelin, glucagon, and glucagon-like peptide-1 (GLP-1) in relation with differing fasting insulin levels. We hypothesized that these hormones are affected by insulin resistance, and hence, we compared different postprandial responses of GLP-1, glucagon, and ghrelin in subjects with relatively high (RHI) or relatively low (RLI) fasting insulin levels. The trial was a randomized crossover study with 4 different meal conditions. Fourteen nonobese or obese, healthy, men and 14 women were randomly assigned to the order of supervised intake of a 750 kcal drink with the same protein contents but with 20 energy-percent (E%) or 55 E% from carbohydrates, and the remaining energy from fat. Participants were also randomized to consume the drinks as 1 large beverage or as five 150-kcal portions every 30 minutes. The 28 subjects were divided into 2 equally sized groups based on fasting insulin levels. Statistics were done with general linear mixed model. Fasting insulin levels were 3-fold higher in the group with RHI compared with the RLI group (RHI: 1004 ± 510 pg/mL, RLI: 324 ± 123 pg/mL, P <.0005). Serum GLP-1 was highest in the RHI group after both single meals and after 5 drinks and following high- and low-carbohydrate meals (both P ≤.002), and this was the case also for glucagon levels (both P ≤.018), whereas ghrelin levels did not differ between groups. Thus, subjects with RHI displayed both higher postprandial serum GLP-1 and glucagon than the participants with RLI, suggesting that glucagon could play a role in the advent of dysglycemia by insulin resistance. [ABSTRACT FROM AUTHOR]

Background Controlled glycemic concentrations are associated with a lower risk of conditions such as cardiovascular disease and diabetes. Models commonly used to guide interventions to control the glycemic response to food have low efficacy, with recent clinical guidelines arguing for the use of personalized approaches. Objective We tested the efficacy of a predictive model of personalized postprandial glycemic response to foods that was developed with an Israeli cohort and that takes into consideration food components and specific features, including the microbiome, when applied to individuals from the Midwestern US. Design We recruited 327 individuals for this study. Participants provided information regarding lifestyle, dietary habits, and health, as well as a stool sample for characterization of their gut microbiome. Participants were connected to continuous glucose monitors for 6 d, and the glycemic response to meals logged during this time was computed. The ability of a model trained using meals logged by the Israeli cohort to correctly predict glycemic responses in the Midwestern cohort was assessed and compared with that of a model trained using meals logged by both cohorts. Results When trained on the Israeli cohort meals only, model performance for predicting responses of individuals in the Midwestern cohort was better (R = 0.596) than that observed for models taking into consideration the carbohydrate (R = 0.395) or calorie content of the meals alone (R = 0.336). Performance increased (R = 0.618) when the model was trained on meals from both cohorts, likely because of the observed differences in age distribution, diet, and microbiome. Conclusions We show that the modeling framework described in Zeevi et al. for an Israeli cohort is applicable to a Midwestern population, and outperforms commonly used approaches for the control of blood glucose responses. The adaptation of the model to the Midwestern cohort further enhances performance and is a promising means for designing effective nutritional interventions to control glycemic responses to foods. This trial was registered at clinicaltrials.gov as NCT02945514. [ABSTRACT FROM AUTHOR]

Moderate chemical pretreatment to increase the energy density and improve of chemical components, also called preconversion, is an emerging strategy to secure feedstock supplies in biorefinery systems. This study investigates the alkaline hydrogen peroxide (AHP) preconversion of softwood for its potential use at distributed depots, which are preprocessing facilities near natural resource sources. Specifically, this study quantified the effects of treatment conditions such as hydrogen peroxide concentration, reaction temperature, and time on chemical compositions and enzymatic hydrolysis. Results show that AHP preconversion led to the removal of lignin and hemicellulose from the recovered solids. Increasing the concentration of hydrogen peroxide decreased carbohydrate recovery after the preconversion process. There was no significant difference of total sugar yield from enzymatic hydrolysis at various hydrogen peroxide loadings. Carbohydrate recovery was over 96% after preconversion at 30 °C compared to that of the untreated sample. A longer reaction time increased the total enzymatic sugar yields. Morphological analysis revealed significant structure modification, with cracks and fragments in Douglas-fir after AHP preconversion. • AHP mild chemical preconversion improves the carbohydrates density of feedstock. • AHP prevonversion results in removal of partial hemicellulose and lignin. • The effect of AHP process conditions on carbohydrate recovery was elucidated. • Carbohydrate recovery of over 96% was obtained at lower temperature condition. [ABSTRACT FROM AUTHOR]

Pistachio ( P. vera L., Anacardiaceae) is cultivated in regions where soil water deficits and salinity conditions are higher than usual. Despite adult pistachio trees having been documented as being drought tolerant; there is only a limited understanding of the physiological mechanisms pistachio cultivars use to survive drought. We therefore, carried out a greenhouse experiment to evaluate the effects of three osmotic drought stress treatments including; control conditions (−0.1 MPa), moderate (−0.75 MPa) and severe drought (−1.5 MPa) stress, using PEG 6000 for 14 days with a subsequent two weeks recovery period. Carbohydrate contents, relative water content, water use efficiency, stomatal characteristics, and nitrogen and carbon isotope composition were evaluated in three Iranian pistachio cultivars, i.e. Akbari, Kaleghochi and Ohadi. Results revealed that the drought stress treatments induced osmotic adjustment by carbohydrate accumulation. Both drought stress treatments increased soluble carbohydrate and starch contents of the leaves. Relative water content was only affected by drought stress in Kaleghochi. Stomatal density and morphology varied with pistachio cultivars but was hardly affected by the stress treatments. Drought stress significantly increased the overall mean of water use efficiency (intrinsic and instantaneous WUE). There were no significant differences between the leaf carbon isotope compositions of all pistachio cultivars under stress. This indicates that this relation may not be used to determine pistachio cultivars with appropriate WUE via leaf carbon isotope composition within the time frame of the experiment. Leaf nitrogen isotope composition decreased under drought stress regardless off the cultivar. [ABSTRACT FROM AUTHOR]

For biomass production of Spirulina platensis as feedstock of fermentation, the culture characteristics of three typical mutants of 3-A10, 3-B2 and 4-B3 generated by atmospheric and room temperature plasmas (ARTP) mutagenesis were systematically studied by using CO 2 aeration culture system and compared with the wild strain. The specific growth rate of wild strain in the pure air aeration culture system exhibited a 76.2% increase compared with static culture, while the specific growth rates of the 3-A10, 3-B2 and 4-B3 in pure air aeration culture system were increased by 114.4%, 95.9% and 88.2% compared with their static cultures. Compared with static culture, the carbohydrate contents of wild strain, 3-A10, 3-B2 and 4-B3 in pure air aeration culture system dropped plainly by 51.0%, 79.3%, 85.5% and 26.1%. Increase of CO 2 concentration enhanced carbohydrate content and productivity. Based on the carbohydrate productivity, the optimal inlet of CO 2 concentration in aeration culture was determined to be 12% (v/v). Under this condition, 3-B2 exhibited the highest carbohydrate content (30.7%), CO 2 fixation rate (0.120gCO 2 ·g −1 ·d −1 ) and higher growth rate (0.093 g L −1 ·d −1 ), while 3-A10 showed the highest growth rate (0.118 g L −1 ·d −1 ) and higher CO 2 fixation rate (0.117gCO 2 ·g −1 ·d −1 ) but low carbohydrate content (24.5%), and 4-B3 showed the highest chlorophyll (Chl) content (3.82 mg·g −1 ). The most outstanding mutant by static culture in terms of growth rate and carbohydrate productivity (3-B2), was also demonstrated by CO 2 aeration culture system. This study revealed that the ARTP mutagenesis could generate the S. platensis mutants suitable for CO 2 aeration culture aiming at biomass production. [ABSTRACT FROM AUTHOR]

Abstract: Sedimentation and density are important factors influencing the growth of wetland plants. The aim of this study was to elucidate the role of plant density in acclimation to burial stress by investigating the growth, biomass allocation, and carbohydrate contents of Polygonum hydropiper L. var. flaccidum, one of the dominant species in the Dongting Lake wetland, China. Experimental treatments, conducted in a greenhouse, combined three plant densities (16, 144, and 400 plants m−2) with two burial depths (0 and 15cm) in a factorial design. Greater burial depth and higher plant density had negative effects on biomass accumulation and plant height with some exceptions. Plant growth, although lower at higher densities in general, was unaffected by burial depth at medium and high densities, indicating that the negative effect of burial stress was ameliorated by increased plant density. Deeper burial led to higher stem mass fraction only in the low-density treatment. Belowground mass fraction increased significantly with increasing density in both burial treatments. Moreover, higher density and deeper burial led to higher soluble sugar content but lower starch content. These data indicate that higher density facilitates acclimation of P. hydropiper to burial stress through increased soluble sugar content. [Copyright &y& Elsevier]

Facing the huge output of food waste (FW) and paper waste (PW), long-term semi-continuous experiments were carried out to investigate the effect of the substrate organic composition on mesophilic and thermophilic anaerobic co-digestions (Co-ADs) of their mixtures. The experimental results showed that the organic composition of the substrate affected the biogas and methane production and yield of the two Co-ADs of the FW and PW mixtures, and its effect on thermophilic Co-AD (Co-TAD) was lower than that on mesophilic Co-AD (Co-MAD). The two Co-ADs had similar biogas (2.158 ± 0.136 L/L/d and 2.183 ± 0.142 L/L/d) and methane production (1.245 ± 0.082 L/L/d and 1.279 ± 0.088 L/L/d), and organic matter degradation (81.79 ± 1.07% and 83.81 ± 1.09%) when the substrate organic composition was carbohydrates:proteins:lipids = 6.8:1.8:1 (low carbohydrate composition, FW:PW = 4:1). When the substrate organic composition was carbohydrates:proteins:lipids = 13.5:2:1 (high carbohydrate composition, FW:PW = 1:1), the thermophilic temperature was more favorable than the mesophilic temperature for the Co-AD of FW and PW mixtures. The characteristics (pH, total ammonia, total volatile fatty acids, and total alkalinity) of the Co-TAD digestate were more sensitive to changes in the organic composition of the substrate than those of the Co-MAD digestate. Increasing the carbohydrate content of the FW:PW mixture lowered the production of biogas and methane, and degradation of organic matter in both Co-ADs. [Display omitted] • Substrate organic composition affect the performance of two Co-ADs of FW and PW. • Increasing carbohydrate content of the mixture lowered the gas production of both Co-ADs. • Performance of Co-TAD was less effected by substrate organic composition. • Co-TAD digestate were more sensitive to the substrate organic composition. [ABSTRACT FROM AUTHOR]

Abstract: We tested the hypothesis whether developmental acclimation at ecologically relevant humidity regimes (40% and 75% RH) affects desiccation resistance of pre-adults (3rd instar larvae) and adults of Drosophila melanogaster Meigen (Diptera: Drosophilidae). Additionally, we untangled whether drought (40% RH) acclimation affects cold-tolerance in the adults of D. melanogaster. We observed that low humidity (40% RH) acclimated individuals survived significantly longer (1.6-fold) under lethal levels of desiccation stress (0–5% RH) than their counter-replicates acclimated at 75% RH. In contrast to a faster duration of development of 1st and 2nd instar larvae, 3rd instar larvae showed a delayed development at 40% RH as compared to their counterparts grown at 75% RH. Rearing to low humidity conferred an increase in bulk water, hemolymph content and dehydration tolerance, consistent with increase in desiccation resistance for replicates grown at 40% as compared to their counterparts at 75% RH. Further, we found a trade-off between the levels of carbohydrates and body lipid reserves at 40% and 75% RH. Higher levels of carbohydrates sustained longer survival under desiccation stress for individuals developed at 40% RH than their congeners at 75% RH. However, the rate of carbohydrate utilization did not differ between the individuals reared at these contrasting humidity regimes. Interestingly, our results of accelerated failure time (AFT) models showed substantial decreased death rates at a series of low temperatures (0, −2, or −4°C) for replicates acclimated at 40% RH as compared to their counter-parts at 75% RH. Therefore, our findings indicate that development to low humidity conditions constrained on multiple physiological mechanisms of water-balance, and conferred cross-tolerance towards desiccation and cold stress in D. melanogaster. Finally, we suggest that the ability of generalist Drosophila species to tolerate fluctuations in humidity might aid in their existence and abundance under expected changes in moisture level in course of global climate change. [Copyright &y& Elsevier]

Abstract: Two rice genotypes with different drought tolerance, namely Jin 23B (drought tolerant) and Zhenshan 97B (drought sensitive), were used to study the antioxidant enzyme activities, soluble sugar and starch contents in spikelets, pistil water potential and pollen number on a stigma under water-deficit stress at the flowering stage, which were involved in the spikelet sterility. Compared with respective controls, drought stress induced more serious decreases of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities and more significant increase of malonaldehyde (MDA) content in spikekets of Zhenshan 97B than in Jin 23B on 9 and 12 days after water stress (DAWS). The soluble sugar and starch contents increased significantly in spikelets of Jin 23B, but decreased significantly in spikelets of Zhenshan 97B during 9-12 DAWS. The pistil maintained higher water potential in Jin 23B than in Zhenshan 97B during 3-6 DAWS and 9-12 DAWS. In addition, water stress induced more significant decrease in the pollen number on a stigma as well as the percentage of unfilled grains in Zhenshan 97B than in Jin 23B. Thus, it is suggested that water stress induced spikelet sterility by damaging antioxidant enzyme activities, reducing carbohydrate content in spikelets and decreasing pistil water potential at the flowering stage in rice. [ABSTRACT FROM AUTHOR]

Early spring leaf out is important to the success of deciduous trees competing for light and space in dense forest plantation canopies. In this study, we investigated spring leaf flush and how long-term growth at elevated carbon dioxide concentration ([CO2]) and elevated ozone concentration ([O3]) altered leaf area index development in a closed Populus tremuloides (aspen) canopy. This work was done at the Aspen FACE experiment where aspen clones have been grown since 1997 in conditions simulating the [CO2] and [O3] predicted for ∼2050. The responses of two clones were compared during the first month of spring leaf out when CO2 fumigation had begun, but O3 fumigation had not. Trees in elevated [CO2] plots showed a stimulation of leaf area index (36%), while trees in elevated [O3] plots had lower leaf area index (−20%). While individual leaf area was not significantly affected by elevated [CO2], the photosynthetic operating efficiency of aspen leaves was significantly improved (51%). There were no significant differences in the way that the two aspen clones responded to elevated [CO2]; however, the two clones responded differently to long-term growth at elevated [O3]. The O3-sensitive clone, 42E, had reduced individual leaf area when grown at elevated [O3] (−32%), while the tolerant clone, 216, had larger mature leaf area at elevated [O3] (46%). These results indicate a clear difference between the two clones in their long-term response to elevated [O3], which could affect competition between the clones, and result in altered genotypic composition in future atmospheric conditions. [Copyright &y& Elsevier]

Abstract: Over-winter mortality of juvenile aquacultured northern quahogs (=hard clams), Mercenaria mercenaria, is a significant problem for the Mid-Atlantic and Northeast aquaculturists. Although protecting seed from predators improves survival, significant mortalities still frequently exceed 50%. The mortality has been attributed to severe winter temperatures, however, this suggestion has yet to be systematically investigated. We hypothesize that extended periods of low water temperatures (<5 °C) will result in reduced hard clam pumping, and a subsequent increase in the use of energy stores for metabolism. This would then lead to demise in physiological condition and cause mortality in the spring when water temperatures increase, food levels are low and metabolic demand is high. In this study, juvenile aquacultured hard clams were planted at two sites in Jamaica Bay, New York during the fall in the years of 2001, 2002, and 2004, to investigate the magnitude and mechanisms of action of over-winter mortality through the winter and spring. Measurements of temperature, chlorophyll-a, and total clam biochemical composition were conducted to identify any correlations with over-winter mortality. The field data indicate that a mild winter (2001–2002) results in negligible mortality. Similarly, a severe winter (2004–2005) followed by a spring in which the rise in water temperature coincides with high food (chlorophyll-a) levels also results in low mortality. In contrast, significant mortality (up to 0.99% per day) occurs in the spring following a severe winter (2002–2003), at a time when water temperatures are rising but food levels are low (Chl-a <3 µg L−1). During this period a rapid decline of carbohydrate content is observed, suggesting the use of energy reserves to maintain metabolic activity. Mortality is associated with carbohydrate levels below 10% of the tissue dry weight. Therefore, it appears that significant mortality of juvenile aquacultured hard clams occurs when phytoplankton abundance is low as water temperature is increasing during the spring. It would be more appropriate to refer to this phenomena as a winter–spring mortality. [Copyright &y& Elsevier]