Stages Of Culture Research Articles

Analysis of the fisheries industry and the development of its feed supply, taking into account biologically active substances

The study presents the results of the assessment of the current state of the fisheries complex, the dynamics of extraction (catch) of aquatic biological resources, the state of the feed industry for certain types of feed. The study was conducted on the basis of relevant statistical, scientific, practical, and other materials in the field of activity of the fishery complex. The analysis was carried out in accordance with the key indicators identified. The State Program for the development of the fishery complex of the Russian Federation. A significant place in ensuring the positive dynamics of the development of the fishing industry is given to feed. Indicators of feed production are generally growing for older age and sex fish groups. Nevertheless, for the repair of young animals at the early stages of cultivation, to stimulate vitality and immunity, so-called starter, production and functional feeds containing specific ingredients and probiotics are required - biologically active substances that are not produced enough. As a result, a significant proportion of imported feed remains.

SUITABILITY ANALYSIS OF TOBACCO CULTIVATION TECHNIQUE IN NAGARI BARUAH GUNUNG

The problem with tobacco farmers in Nagari Baruah Gununang is a productivity. Tobacco productivity is below national productivity due to cultivation techniques that do not comply with standards. The research method uses suitability analysis to assess the level of suitability of cultivation techniques used by farmers in Nagari Baruah Gunuang. The level of suitability is analyzed using check sheet based on a likert scale by comparing farmers actual and standards cultivation. The research results show that suitability level of tobacco cultivation technique is 70%. This means that the cultivation techniques used by farmers are still classified as almost in accordance with standards. The stages of cultivation that do not meet standards are planting; fertilization; and weeding, watering and loosening. The problems that cause non-compliance with this standard are close spacing of plants, lack of use of manure and dolomite, inappropriate dosage and type of chemical fertilizer, and insufficient watering and irrigation.

SURMA NODIR CHOKHE JAL': SOCIO-CULTURE OF SURMA BARAK

The village life of the region depicted in the Novel is Jagdishpur village of undivided Cachar district. This district has a special importance in terms of regional folk culture, the society of this region is formed based on the geographic environment, economy, education etc. of the region.The life-centered Novel 'Surma Nodir Chokhe Jal' depicts the fruits of real experience. The characters of this novel represent the village of Jagdishpur described in the novel. While describing the nature of Jagdishpur village and the life practices of the people, the novelist has presented various aspects of the folk culture of the region very well. We have noticed that being a major agricultural region, it is really surprising to think about the various stages of rice cultivation. Again through the songs, we noticed that the wedding songs that have been playing for a long time on various occasions are the bearers and bearers of their own traditional traditions. There is a variety of subject matter in the songs as well as a variety of style. There is a distinct language and expression of thought.

Effects of Sprouted Barley with Different Cultivation Stages on Fermentation Characteristics and Degradation Kinetics in the Rumen

The present study investigated the effects of sprouted barley (SB) with different cultivation stages on fermentation characteristics and degradation kinetics in the rumen. The SB was cultivated in three different stages as follows: 0, 4, and 8 days. Dried samples from each cultivation stage of SB were incubated in the rumen buffer at 39 °C for 48 h in quadruplicate with three blanks. Dry matter (DM) and neutral detergent soluble carbohydrate concentrations of SB decreased linearly (p = 0.001) by increasing the cultivation stage, while crude protein, neutral detergent fiber (NDF), acid detergent fiber, and hemicellulose concentrations increased linearly (p ≤ 0.001). Total volatile fatty acid and butyrate in the rumen decreased linearly (p ≤ 0.020) by increasing the cultivation stage, while pH and propionate increased linearly (p < 0.001). The total degradation fraction of DM and NDF increased quadratically (p ≤ 0.003). The fraction degradation rate of DM and NDF decreased linearly (p ≤ 0.001) by increasing the cultivation stage, while the lag phase increased linearly (p ≤ 0.010). The present study concluded that cultivated SB at 4 days was recommended for animal feed due to the highest nutrient degradation in the rumen without any adverse effects on fermentation characteristics.

CHARACTERISTICS OF THE GROWTH OF HEIFFS OF DIFFERENT LINES OF THE BUKOVINY FACTORY TYPE OF THE UKRAINIAN RED-AND-WHITE DAIRY BREED

The study was carried out in the herd of the Myrne breeding farm of the Chernivtsi region on animals of the Bukovyna factory type of the Ukrainian Red-and-White dairy breed. It was established that heifers of the Bukovin factory type of the Ukrainian Red-and-White dairy breed were characterized by good indicators of live weight. In newborn animals, this indicator was 31.9 kg, by the age of 6 months it increased by 5.4 times or by 134.5 kg, by the age of 12 months – by 9.7 times or by 266.9 kg and by 18 – one month old – 13 times or by 369.8 kg. The average age of the first insemination in the herd was 15.5 months, and the live weight of animals at this age was 365.2 kg. The coefficients of variation of live weight, depending on age, were in the range of 8.9–17.1%. This indicator was the lowest in 18-month-old animals. The variability of the multiplicity of increase in live weight was within 18.4–21.3%. It should be noted that the highest coefficients of variation of the multiplicity of live weight increase (21.3%) were observed in 12-month-old heifers. The highest average daily gains were observed in heifers from 3 to 6 months of age and amounted to 825 g, with a variability of 26.8%. Later, with increasing age of the animals, this indicator decreased and in the age period from 15 to 18 months it was 550 g with a variability of the sign of 56.2%. In general, from birth to 18 months of age, the average daily weight gain of heifers was 684.1 g. A comparative analysis of the dynamics of the live weight of heifers of different lines showed that the heifers of the Starbuck line were better in terms of live weight at birth (34.0 kg) compared to their peers other lines During the 18-month growing period, repair heifers of the Starbuck line were significantly better compared to peers of other lines. At the final stage of cultivation, with an average live weight of 417 kg, they exceeded their peers by 8–64 kg. The average daily gain of live weight in the period from birth to 18 months of age was the highest in heifers of the Starbuck line at an average of 710 g, while in their peers of other lines it was lower by 21–112 g. With the creation of proper growing conditions, heifers are capable of high growth intensity and high milk productivity in the following stages of the technological production cycle of obtaining high-quality products.

Pretreatment of palm oil mill effluent (POME) for Spirulina cultivation

Palm Oil Mill Effluent (POME) is liquid waste produced from palm oil processing. The quantity of POME in Indonesia has increased from year by year. POME is not a toxic material, but it will be very dangerous if it is thrown directly without pre-processing, because it will harm the aquatic ecosystem due to its high content of COD (Chemical Oxygen Demand) and BOD (Biological Oxygen Demand). POME has also a high content of nitrogen (N) and phosphor (P), which make POME can be used as medium for microalgae growth. Therefore, this research is aimed to study pretreatment and to utilize its nutrient content (N, P) for medium of spirulina growth. Pretreatment of POME research was conducted by using two stage of cultivation (Chlamydomonas and Chlorella) and dilution factor (0-4x). The result of this pretreatment was then used for Spirulina growth. Spirulina cultivation was conducted by nutrient addition and without nutrient addition. This research showed that the best performing variation of dilution rate to cultivate Spirulina is 4x dilution. It showed that 4x dilution could reduce COD content until 128.33 mg/L. Besides that, in 4x dilution, microalgae as Chlamydomonas, Chlorella, and Spirulina had the highest growth rate as compared to 2x dilution and without dilution. The best wild algae for pretreatment of POME is Chlorella. Because by using wild algae Chlorella, COD content could be reduced until 128.33 mg/L and achieve the lowest COD content compared with Chlamydomonas. For microalgae growth, addition of nutrient is better than without nutrient, because nutrient could enhance Spirulina photosynthesis.

Life Cycle Assessment of the Sugarcane Supply Chain in the Brazilian Midwest Region

The sugarcane supply chain is one of the main contributors to economic development in many countries. However, it is necessary to consider the relationship of this supply chain with the environment in order to reduce/mitigate adverse environmental impacts. Life cycle assessment (LCA) supports improving the relationship between production systems and the environment, increasing process efficiency, and reducing costs. The main objective of this research was to identify the extent to which the sugarcane supply chain impacts environmental and human health aspects as well as the use of resources through LCA. This analysis focused on a supply chain in Brazil’s Midwest region, considering the stages of cultivation, transportation, and production. The results indicated that using fertilizers and pesticides and burning crops during harvest severely threaten the sustainability of this supply chain. Also, using crude oil, natural gas, coal, and other chemical products in ethanol production is a critical threat to the sustainability of the sugarcane supply chain. The obtained results cooperate with the decarbonization goals assumed by Brazil at the United Nations Climate Change Conference 2015 (COP 21). A multidimensional approach is necessary to assess the sugarcane production chain results, and the LCA method is appropriate for performing this analysis.

EXPLORING THE IMPACT OF SOIL AMENDMENTS ON FOOD SAFETY AND CROP PRODUCTIVITY FOR SUSTAINABLE AGRICULTURE

Aflatoxins impact the entire food supply chain, from agricultural fields to processing facilities, markets, and consumer tables. In peanut cultivation, this threat poses a constant challenge throughout the cultivation, processing, and consumption stages. To confront this challenge, an exhaustive study was undertaken with the aim of investigating the effects of targeted soil amendments; namely, Vermicompost, Lentil crop residue, and Sulphate of Potash applied during the pivotal sowing phase at two distinct locations, Chakwal and Attock. The research includes meticulous groundnut sample analysis to quantify aflatoxin levels, revealing a significant reduction across all soil amendments compared to the control group. Vermicompost stands out as the most effective, achieving a remarkable 64.8% reduction, followed closely by Sulphate of Potash at 62.4%. Statistical analysis highlights non-significant differences among amendments. Beyond aflatoxin mitigation, the study underscores the dual benefit of these soil amendments, contributing not only to mycotoxin control but also enhancing overall crop productivity. Percent increase in number of grains per plant ranged between 58.82% to 43.53% whereas in hundred grain weight it ranged between 17.10% and 10.55%. In summary, the study emphasizes the importance of strategic soil amendments, particularly Vermicompost and Sulphate of Potash, in mitigating aflatoxin contamination in peanuts. The dual benefit of improved crop productivity adds significance to the findings, offering a holistic approach to address the multifaceted dimensions of aflatoxin challenges in peanut cultivation.

Detection of human enteric viruses in fresh produce of markets, farms and surface water used for irrigation in the Tehran, Iran

Considering the major role of vegetables in the transmission of gastrointestinal diseases, investigation of the presence of gastrointestinal viruses is particularly important for public health. Additionally, monitoring and investigating potential points of contamination at various stages of cultivation, harvesting, and distribution can be important in identifying the sources of transmission. This study was conducted with the aim of identifying norovirus, adenovirus, hepatitis A virus, hepatitis E virus, rotaviruses, and astroviruses in vegetable samples from the fields and fruit and vegetable centers of Tehran City, and to investigate their presence in irrigation water by RT-qPCR. This study was carried out in two phases: initial and supplementary. During phase I, a total of 3 farms and 5 fruit and vegetable centers and a total of 35 samples from farms, 102 samples from fruit and vegetable centers and 8 agricultural water samples were collected. Zero, 16 and 1 samples were positive for at least one of the viruses from each of the sources, respectively. During phase II, 88 samples from 23 farms, 226 samples from 50 fruit and vegetable centers and 16 irrigation water samples were collected, with 23, 57 and 4 samples were positive for at least one virus, respectively. Rotavirus was the most frequently identified virus among the samples, followed by NoV GII, NoV GI, AstV, and AdV. HAV and HEV were not detected in any of the tested samples. The results of this study suggest that there may be a wide presence of viruses in vegetables, farms, and fruit and vegetable centers in Tehran City, which could have significant consequences considering the fact that many of these foods are consumed raw. Additionally, the detection of some of these viruses in irrigation water suggests that this may be a potential route for viral contamination of produce.

FROM FIELD TO FORKS: A DEEP DIVE INTO AFLATOXIN CONTAMINATION IN FOOD ITEMS

Aflatoxin contamination in food items pretences a significant hazard to global foodstuff safety, public health, and economic stability. This assessment comprehensively examines the sources, risks, and potential solutions associated with aflatoxin contamination in various food products. Aflatoxins, produced by moulds of the Aspergillus genus, contaminate crops during cultivation, harvest, storage, and processing stages. Consumption of aflatoxin-contaminated food items has been linked to severe health issues, including liver cancer, stunted growth, and immune system suppression. This review delves into the diverse sources of aflatoxin contamination, ranging from agricultural practices and environmental factors to storage conditions. The risks associated with aflatoxin exposure are explored in detail, emphasizing the global impact on both human health and economies, especially in vulnerable communities reliant on staple crops. Furthermore, the review discusses multifaceted solutions aimed at mitigating aflatoxin contamination. These solutions encompass agricultural strategies such as crop rotation, improved irrigation methods, and biocontrol agents, as well as advancements in food processing techniques like sorting, washing, and hermetic storage. Regulatory measures and international standards are critically evaluated, highlighting their role in ensuring food safety and preventing aflatoxin-related health crises. Keywords : Aflatoxin, Contamination, Public Health, Global Foodstuff Safety

Characterization of microbial communities during Grifola frondosa (maitake) wood log cultivation

The method used to cultivate the popular Japanese mushroom Grifola frondosa (maitake), called 'wood log cultivation', comprised two steps: (1) the mycelium is grown around a wood log in a plastic bag, and (2) the mycelium that has spread on the wood log is transferred into casing substrates in a forest. This method is still popular in Japan due to its low cost and high-quality crop production. The importance of the microbiome that inhabits mushroom-cultivation surroundings has recently attracted attention, but no study of the microbial communities in maitake cultivation has been published. We investigated how the bacterial communities changed in wood logs in comparison with a control group (without inoculation) and their interaction with maitake during the first to fourth years of maitake wood log cultivation. A maitake biomass was detected by quantitative PCR in wood logs but not in the casings, and we thus decided to investigate the bacterial communities in wood log samples for control and first- to fourth-year cultivation. The results indicate that the phyla Proteobacteria, Firmicutes, and Gemmatimonadota play key roles in changes of the microbiome composition for maitake wood log cultivation. In a functional profile, bacteria communities in the wood logs during maitake cultivation showed higher relative abundance in cellulolysis, glycolysis, TCA cycle, and many biosynthesis pathways, whereas the control group showed higher relative abundance in fermentation. These results suggested that (i) the bacterial communities which inhabited maitake cultivated wood logs may help the maitake degrade wood cellulose, and (ii) part of the glucose from the cellulose degraded by both maitake and bacteria was used for the bacterial TCA cycle instead of fermentation. Bacteria also produce some chemicals that maitake mycelium may need. It is also likely that some potential intracellular parasites dwell with maitake. The different cultivation stages showed different network structures. A network analysis indicated that Class Gammaproteobacteria is a potential keystone taxon for the microbiome network stability of maitake cultivated wood logs. These results contribute to the understanding of the microbiome in maitake-cultivation surroundings and will improve maitake wood log cultivation.

Overexpression of the Transcription Factor Azf1 Reveals Novel Regulatory Functions and Impacts β-Glucosidase Production in Trichoderma reesei.

The fungus Trichoderma reesei is an essential producer of enzymes that degrade lignocellulosic biomass to produce value-added bioproducts. The cellulolytic system of T. reesei is controlled by several transcription factors (TFs) that efficiently regulate the production of these enzymes. Recently, a new TF named Azf1 was identified as a positive regulator of cellulase expression. Here, we investigated novel regulatory functions of Azf1 by its overexpression. In the mutant strain OEazf1, overexpression of azf1 was achieved under both repression and induction conditions. Although azf1 was more abundant in transcript and protein, overexpression of this TF did not activate transcription of the cellulase gene in the presence of the repressor glucose, suggesting that Azf1 may be subject to posttranslational regulation. In cellulose, the expression of swo, encoding the accessory protein swollenin, and the β-glucosidases cel1a, cel1b, cel3b, and cel3g increases in the early stages of cultivation. The increased production of these β-glucosidases increases the hydrolysis rate of cellobiose and sophorose, which activates carbon catabolite repression (CCR) and causes repression of cellulase genes and the regulator Xyr1 in the later stages of cultivation. Moreover, overexpression of azf1 led to increased cellulase activity in T. reesei during long-term cultivation in cellulose and sugarcane bagasse. Our results provide new insights into the mechanisms regulating Azf1 and novel genes that are important targets of this TF. This work contributes to a better understanding of the complex mechanisms regulating cellulase expression in T. reesei. It will contribute to the development of strains with higher production of these essential enzymes.

The extracellular polysaccharide determine the physico-chemical surface properties of Microcystis.

Microcystis possesses the capacity to form colonies and blooms in lakes and reservoirs worldwide, causing significant ecological challenges in aquatic ecosystems. However, little is known about the determining factors of physico-chemical surface properties that govern the competitive advantage of Microcystis. Here, The physico-chemical surface properties of Microcystis wesenbergii and Microcystis aeruginosa, including specific surface area (SSA), hydrophobicity, zeta potential, and functional groups were investigated. Additionally, the extracellular polysaccharide (EPS) were analyzed. Laboratory-cultured Microcystis exhibited hydrophilic, a negative zeta potential and negatively charged. Furthermore, no significant relationship was shown between these properties and the cultivation stage. Microcystis wesenbergii exhibited low free energy of cohesion, high surface free energy, high growth rate, and high EPS content during the logarithmic phase. On the other hand, M. aeruginosa displayed lower free energy of cohesion, high surface free energy, high EPS content, and high growth rate during the stationary phase. These characteristics contribute to their respective competitive advantage. Furthermore, the relationship between EPS and surface properties was investigated. The polysaccharide component of EPS primarily influenced the SSA and total surface energy of Microcystis. Likewise, the protein component of EPS influenced hydrophobicity and surface tension. The polysaccharide composition, including glucuronic acid, xylose, and fructose, mainly influenced surface properties. Additionally, hydrophilic groups such as O-H and P-O-P played a crucial role in determining hydrophobicity in Microcystis. This study elucidates that EPS influenced the SSA, hydrophobicity, and surface free energy of Microcystis cells, which in turn impact the formation of Microcystis blooms and the collection.

Anaerobic granular sludge performance in an expanded granular sludge bed reactor treating calcium-rich wastewater by adjusting CaCO3 crystallization: Effect of upflow velocity and Ca2+ concentration

The role of upflow velocity and Ca2+ concentration in controlling the type and rate of CaCO3 crystallization and their impacts on the anaerobic granular sludge (AnGS) formation and performance in an expanded granular sludge bed (EGSB) reactor were studied. The results showed that an improved upflow velocity could promote metastable CaCO3 crystals and achieve the optimized portion of vaterite with a value of 84 % at 10 m/h with a small amount of aragonite, thus limiting the scaling in the reactor. The removal efficiency of Ca2+ was to some extent positively correlated to the influent Ca2+ concentration, but declined when Ca2+ exceeded a specific threshold. Vaterite was dominant with the increase of Ca2+ concentrations of the influent. Compared with granules in R1 (Ca2+ 10 mg/L) and R2 (Ca2+ 100 mg/L), granules cultivated in R3 (Ca2+ 800 mg/L) revealed maximum amount of biomass with biggest particle size distribution and fastest average settling rate, with relative stable COD removal efficiency and the fast optimized reactor capacity at OLR of 16 kgCOD/m3d. A low upflow velocity and a higher Ca2+ concentration promoted nucleus formation and granules growth at the initial cultivation stage of the EGSB reactor. The Ca2+ concentration had a significant impact on the bacterial community and favoured the growth of Tolumonas and Anaeromousa Anaeroarcus. Archaea, rather than bacteria, was strengthened to contribute more to methane production at a relatively high Ca2+ concentration.

Prediction of Growth and Quality of Chinese Cabbage Seedlings Cultivated in Different Plug Cell Sizes via Analysis of Image Data Using Multispectral Camera

In recent times, there has been an increasing demand for the development of rapid and non-destructive assessment of the growth and quality of seedlings before transplanting. This study was conducted to examine the growth and quality of Chinese cabbage seedlings that can be determined via the image data acquired using a multispectral camera. Chinese cabbage seedlings were cultivated in five different plug trays (72, 105, 128, 162, and 200 cells/tray) for 30 days after sowing (DAS). The growth of seedlings had no significant difference in the early stage of cultivation; however, it decreased with increasing the number of cells in the plug tray due to the restricted root zone volume in the mid to late stages. Individual leaf area was predicted by analyzing of image data with high accuracy (R2 > 0.8) after 15 DAS; however, the accuracy of leaf area prediction per tray decreased due to overlapping and twisting leaves. Among six different vegetation indices, mrNDVI showed a high correlation (R2 > 0.6) with the dry weight of seedlings at 25 and 30 DAS. We confirmed that the leaf area of seedlings can be predicted non-destructively by analyzing the acquired image data per seedling and tray and suggested the applicability of vegetation indices for predicting the growth and quality of vegetable seedlings.

Optimization of Photoautotrophic Growth Regimens of Scenedesmaceae alga: The Influence of Light Conditions and Carbon Dioxide Concentrations

Improving methods for landless production of bioproducts is considered an important stage in the development of the modern bioeconomy. In this context, microalgal biomass is one of the most promising sources of valuable substances due to its rich biochemical composition. Despite the high adaptability of microalgae to various environmental factors, the effectiveness of cultivation systems depends on precisely selected parameters. Both the light conditions and the supply of inorganic carbon sources are key in determining the efficiency of photoautotrophic cultivation. In this work, the effect of a high daily photosynthetic photon flux density (PPFD) ranging from 37.44 to 112.32 mol m−2 day−1 on the growth and productivity of a novel Scenedesmaceae alga, strain EZ-B1, was assessed. The next stage of cultivation consisted of selecting the optimal CO2 concentration. Improved performance of microalga during cultivation in a photobioreactor was achieved at 112.32 mol m−2 day−1 (24 h photoperiod) and by supplying 2% CO2, as evidenced by the high biomass productivity (0.69 g L−1 day−1), total biomass yield (5.23 g L−1), and ammonium nitrogen consumption rate. The data obtained suggest that a higher level of PPFD led to the highest growth rate of the novel strain and the highest biomass productivity, which, in practice, will increase production capacity.

Altered Expression of Two Small Secreted Proteins (ssp4 and ssp6) Affects the Degradation of a Natural Lignocellulosic Substrate by Pleurotus ostreatus

Pleurotus ostreatus is a white-rot fungus that can degrade lignin in a preferential manner using a variety of extracellular enzymes, including manganese and versatile peroxidases (encoded by the vp1-3 and mnp1-6 genes, respectively). This fungus also secretes a family of structurally related small secreted proteins (SSPs) encoded by the ssp1-6 genes. Using RNA sequencing (RNA-seq), we determined that ssp4 and ssp6 are the predominant members of this gene family that were expressed by P. ostreatus during the first three weeks of growth on wheat straw. Downregulation of ssp4 in a strain harboring an ssp RNAi construct (KDssp1) was then confirmed, which, along with an increase in ssp6 transcript levels, coincided with reduced lignin degradation and the downregulation of vp2 and mnp1. In contrast, we observed an increase in the expression of genes related to pectin and side-chain hemicellulose degradation, which was accompanied by an increase in extracellular pectin-degrading capacity. Genome-wide comparisons between the KDssp1 and the wild-type strains demonstrated that ssp silencing conferred accumulated changes in gene expression at the advanced cultivation stages in an adaptive rather than an inductive mode of transcriptional response. Based on co-expression networking, crucial gene modules were identified and linked to the ssp knockdown genotype at different cultivation times. Based on these data, as well as previous studies, we propose that P. ostreatus SSPs have potential roles in modulating the lignocellulolytic and pectinolytic systems, as well as a variety of fundamental biological processes related to fungal growth and development.

How to Diagnose Potassium Abundance and Deficiency in Tomato Leaves at the Early Cultivation Stage

Potassium is one of the indispensable nutrient elements for plant growth, fruit development, and yield. The research and application of potassium nutrition diagnosis technology is the premise of scientific potassium management. However, potassium deficiency in tomato leaves, from vegetative to reproductive growth, is not easy to diagnose. To alleviate this problem, this paper proposes a suitable method of supplying potassium to tomatoes via a nutrient solution and diagnosing potassium abundance and deficiency through diagnosis methods based on ecological morphology, biological accumulation, and the photosynthetic characteristics of tomato plants. The relationship between the ecological morphology and biomass accumulation of tomatoes cultivated in the nutrient solution with potassium supply levels of 1, 4, 8, and 16 mmol/L is also discussed, and the potassium supply in the nutrient solution was studied 21 days after transplanting. The results showed that there was a significant quadratic correlation between the potassium supply in the nutrient solution and plant height and biomass accumulation, respectively. The most suitable level of potassium supply via the nutrient solution was deemed to be 10~13 mmol/L. However, if irreversible damage or severe stress to tomato plants has occurred because of potassium deficiency, there will be serious differences in the growth status of plants, and the diagnosis results will deviate greatly. In addition, the photosynthetic induction characteristics responding to the dark–light conversion of tomato leaves with potassium contents of 0.9%, 2.1%, 3.1%, and 3.3% cultivated with potassium supply amounts of 1, 4, 8, and 16 mmol/L in the nutrient solution were investigated. The results showed that tomato leaves with potassium contents of 3.1% and 3.3% had a more rapid response to dark–light conversion and higher first-order derivatives of net photosynthetic rate compared to those with potassium contents of 0.9% and 2.1%, but the first-order derivative of intercellular CO2 concentration showed an opposite trend. Additionally, a quadratic correlation between leaf potassium content and CO2 assimilation during 5 min of photosynthetic induction was established (R2 > 0.99). According to this correlation, the suitable leaf potassium content was estimated to be 2.3~2.7%, similar to that of tomatoes cultured in the nutrient solution with a 4~8 mmol/L potassium supply. Therefore, this method can realize the rapid, non-destructive, and real-time detection of potassium content in tomato leaves based on a portable photosynthetic measurement system by establishing the relationship between leaf potassium content and net CO2 assimilation during the photosynthetic induction period, therefore helping to avoid the irreversible damage caused by potassium deficiency at the later stages of plant cultivation and providing technical support for the precise fertilization of potassium in actual cultivation.

Exogenous arginine promotes the coproduction of biomass and astaxanthin under high-light conditions in Haematococcus pluvialis

The economical way of Haematococcus pluvialis farming is to simultaneously achieve biomass, astaxanthin and lipid using less expensive chemicals. This paper explores the role of exogenous arginine in promoting growth and astaxanthin accumulation under stressful conditions. The application of arginine exerts a synergic effect on biomass, astaxanthin and lipid by improving carbon utilization, activating the arginine pathway and regulating carotenoid and lipid-related genes. Genes related to arginine catabolism, such as ADC, OCT, ASS1, NOS, and OAT, were up-regulated at both the cultivation and astaxanthin induction stages, signifying their importance in both growth and astaxanthin synthesis. Furthermore, transcriptome analysis revealed that arginine up-regulated transcription levels of genes involved carbon fixing, lipid biosynthesis, pyruvate metabolism, carotenoid, tricarboxylic acid cycle, and arginine and proline metabolism. The results provide a significant mechanism and applicability of using exogenous arginine and high light to stimulate bioproducts from Haematococcus pluvialis.

Environmental footprint performance improvement of black tea using the life cycle assessment approach

The cultivation and production of black tea are associated with significant energy consumption and adverse environmental concerns, largely stemming from inefficient practices, equipment incompatibility, and suboptimal cultivation methods. In response, this study employs a comprehensive life cycle assessment (LCA) to address these issues and identify potential environmental improvements across the entire black tea system, encompassing both the cultivation and production phases. The primary focus of this analysis is the evaluation of key environmental metrics, including global warming potential (GWP), primary energy demand (PED), and water usage (WU). The study's findings highlight that a reduction in the use of chemical fertilizers during the black tea cultivation stage can effectively mitigate GWP, PED, and WU. A sustainable approach involves shifting towards a fertilization scenario that incorporates 70% organic fertilizers and 30% chemical fertilizers. This adjustment makes the cultivation stage more environmentally friendly, resulting in reduced resource depletion and water consumption. Furthermore, the analysis reveals that the application of artificial grass covering, as opposed to herbicides, has a significantly more negative impact on GWP, PED, and WU. Similarly, the use of insecticides during black tea cultivation leads to higher values for GWP, PED, and WU in comparison to employing solar pest control lamps. Additionally, the LCA analysis underscores the effectiveness of integrating solar pest control lamps and herbicide treatments during the black tea cultivation stage to achieve lower GWP and reduced resource consumption. On the other hand, the black tea production stage makes a substantial contribution to the system's GWP, PED, and WU, primarily due to the heated withering and natural fermentation processes. However, transitioning to frozen withering and aerobic fermentation processes presents a more environmentally friendly approach, resulting in a black tea production method that is lower in carbon emissions and energy-efficient, with minimal adverse environmental impact.