Harvest Period Research Articles

People socialize ecological information about the environment but may forget their own experiences: a case study of local ecological knowledge about seed-dispersing animals

Local ecological knowledge (LEK) has been increasingly used in the search for efficient strategies to maintain biological diversity. However, considering the rapid environmental changes in ecosystems, such knowledge may have been lost between generations, affecting its potential application. In this study, we adopted the LEK of the potential dispersers of Caryocar coriaceum Wittm. (Caryocaraceae), an endangered plant species of socioeconomic and cultural importance from northeast Brazil, as a model. We evaluated whether there is intergenerational variation in the LEK about the abundance of Dasyprocta prymnolopha (the principal disperser of C. coriaceum) associated with the local practice of hunting. We collected LEK data from 39 hunter-gatherers aged 31 to 84 years, and camera traps were used during two annual C. coriaceum harvests to record its potential dispersers. Our results indicate that the LEK of the potential animal dispersers of C. coriaceum does not vary between generations; it is disseminated and shared between different generations. The strong interactions among people during the C. coriaceum harvest period facilitate the sharing of information about the potential dispersers of this species. Our results show that hunting D. prymnolopha does not depend on perceptions regarding the availability of this resource in the forest, which may be causing overexploitation. Therefore, local knowledge may need to be updated and connected to the recent and rapid environmental changes because people may believe that current environmental conditions are like those of the past. If this is the case, people may be less cooperative with conservation strategies because they are not aware of environmental changes, so measures to update knowledge about environmental conditions may be necessary to encourage effective participation in management and conservation plans.

Chemical Characterization, Stability and Sensory Evaluation of Sicilian Extra Virgin Olive Oils: Healthiness Evidence at Nose Reach.

The aim of this study was to assess the nutraceutical qualities of extra virgin olive oil (EVOO) samples obtained from three Sicilian olive cultivars: Nocellara, Biancolilla, and Cerasuola. We also evidenced the relationship among biophenols, base parameters and panel test scores, and evaluated the stability of the biophenols in EVOO. The assessment also took into consideration variations in olive harvesting periods and the influence of four different milling methods. A statistical analysis of the collected data revealed that the cultivar and harvesting period were the primary factors influencing the bio-phenol content, while the milling methods employed did not significantly affect the levels of biophenols in the oils. The panel test results were also illuminating as they were strongly related to the cultivar and polyphenol content. Following the criteria outlined in EC Regulation 432/2012, we selected three samples, each representing one of the cultivars, which exhibited the highest bio-phenol content to evaluate the biophenol stability during a time span of 16 months.

The Soil Bacterial Community Structure in a Lactarius hatsudake Tanaka Plantation during Harvest.

Lactarius hatsudake Tanaka is a mycorrhizal edible mushroom with an appealing taste and rich nutrition. It is also a significant food and has medicinal value. In this study, the plantation of L. hatsudake during the harvest period was taken as the research object, and this article explores which bacteria in the soil contribute to the production and growth of L. hatsudake. The soil of the control (CK) and the soil of the mushroom-producing area [including the soil of the base of the mushroom (JT) and the mycorrhizal root soil (JG)] was collected in the plantation. The three sites' bacterial community structure and soil diversity were analyzed using high-throughput sequencing technology, and a molecular ecological network was built. Soil bacteria in the L. hatsudake plantation had 28 tribes, 74 classes, 161 orders, 264 families, 498 genera, and 546 species. The dominant phyla were Proteobacteria and Acidobacteria, and the dominant genera were Burkholderia_Caballeronia_Paraburkholderia, Acidothermus, Bradyrhizobium, Candidatus_Xiphinematobacter, and Granulicella. The α-diversity of soil bacteria in JT was significantly lower than that in JG and CK, and the β-diversity in JT samples was significantly different from that in JG and CK samples. The size and complexity of the constructed network were smaller in JT samples than in JG and CK samples, and the stability was higher in JT samples than in JG and CK samples. The positive correlation between species in JT samples was dominant. The potential mycorrhizal helper bacteria (MHB) species of L. hatsudake was determined using correlation and differential group analysis. The results support future research on mycorrhizal synthesis, plantation management, and the function of microorganisms in the soil rhizosphere of L. hatsudake.

Optimal harvest period and quality control markers of cultivated Flos Chrysanthemi Indici using untargeted/targeted metabolomics, chemometric analysis and in vivo study

Ethnopharmacological relevanceFlos Chrysanthemi Indici (FCI), the flower of Chrysanthemum Indicum L., is a popular traditional Chinese medicine (TCM) for treatment of inflammatory diseases in China. FCI is also a functional food, and is widely used as herbal tea for clearing heat and detoxicating. Aim of the studyTo explore quality control markers of FCI based on the optimal harvest period. Materials and methodsFirst, UPLC-Q-TOF/MS based untargeted metabolomics was applied to explore the chemical profiles of FCIs collected at bud stages (BS), initial stages (IS), full bloom stages (FS) and eventual stages (ES) from eight cultivated regions in China. Subsequently, lipopolysaccharide (LPS)-induced RAW264.7 cell inflammatory model and carrageenan-induced rat paw edema model were used to confirm the anti-inflammatory effect of FCIs collected at IS/FS. Then, UPLC-PDA targeted metabolomics was used to quantitatively analyze 9 constituents with anti-inflammatory activity (7 flavonoids and 2 phenolic acids) changed significantly (VIP > 4) during flowering stages. Finally, ROC curves combined with PCA analysis based on the variation of 9 active constituents in FCIs from different flowering stages were applied to screen the quality markers of FCI. ResultsFCIs at IS/FS had almost same chemical characteristics, but quite different from those at BS and ES. A total of 32 constituents in FCIs including flavonoids and phenolic acids were changed during flowering development. Most of the varied constituents had the highest or higher contents at IS/FS compared with those at ES, indicating that the optimal harvest period of FCI should be at IS/FS. FCI extract could effectively suppress nitric oxide (NO) production in LPS-induced RAW264.7 cells and regulate the abnormal levels of cytokines and PGE2 in carrageenan-induced paw edema model rat. The results of quantitatively analysis revealed that the variation trends of phenolic acids and flavonoids in FCIs were different during flowering development, but most of them had higher contents at IS/FS than those at ES in all FCIs collected from eight cultivated regions, except one sample from Anhui. Finally, linarin, luteolin, apigenin and 3,5-dicaffeoylquinic acid were selected as the Q-markers based on the contribution of their AUC values in ROC and clustering of PCA analysis. ConclusionsOur study demonstrates the optimal harvest period of FCI and specifies the multi-constituents Q-markers of FCI based on the influence of growth progression on the active constituents using untargeted/targeted metabolomics. The findings not only greatly increase the utilization rate of FCI resources and improve quality control of FCI products, but also offer new strategy to identify the Q-markers of FCI.

Phenol content and β-glucosidase activity during the ripening period of olive fruits (Erkence cv.) from different locations

In the present study, Erkence olive fruits were examined during two harvest periods and in two orchards close to the sea at low altitude (A) and far from the sea at higher altitude (B). Olives from the sea-facing northeast (NE) and land-facing southwest (SW) orientations of the trees were analyzed in terms of maturity index, total phenol content, phenolic compounds, β-glucosidase enzyme activity, total protein content and specific enzyme activity. Climate data were collected from the trees and from the meteorology station. The maturity index, β-glucosidase enzyme activity, total protein content and specific enzyme activity of the olives increased during the ripening period. On the other hand, the total phenol content, oleuropein and other phenolic compound contents in the olives decreased. The altitude and location of the fruits on the tree affected the ripening process. Lower altitude and sea-facing side of the tree resulted in an increased enzyme activity, thus aiding in the ripening process.

Contribution of the root system of Cyperus papyrus and Pontederia sagittata to microplastic removal in floating treatment Wetlands in two urban ponds

Microplastic pollution represents a global challenge that threatens ecosystems and human health. Because of this, there has been an increased interest in evaluating the use of phytotechnologies as a natural alternative for the removal of microplastics in water bodies. This study assessed the microplastic removal by Floating Treatment Wetlands (FTWs) consisting of linear arrays planted with Cyperus papyrus and Pontederia sagittata, installed in two urban ponds (“Pond 1” and “Pond 4”) located in the center of the city of Xalapa, Veracruz, Mexico. The results indicated that the two linear arrays of FTWs in Pond 1 (FTW1 and FTW2) efficiently removed microplastics in water column and sediments, with total removal rates of 82.4% and 81.1% respectively, despite having a high initial microplastic concentration. On the other hand, the effectiveness of the two FTWs in Pond 4 was mainly attributed to the first line of plants (FTW3), where the highest removal rates were observed, showing 61.6% in water column and 72.6% in sediments. However, the total removal of the two lines was 64.6% in water and 48.8% in sediments. C. papyrus and P. sagittata plants strongly retained microplastics in their roots, with concentrations of 16.4 and 11.9 mg/g respectively for FTW1 and FTW2 in Pond 1, and 2.1 and 6 mg/g for FTW3 and FTW 4 in Pond 4. These results suggest that the main removal microplastic mechanism was root retention, which facilitates microplastic removal from the aquatic environment by periodical root harvesting. Therefore, the crucial role of roots in the stabilization and reduction of these pollutants is highlighted. This study represents the first report in Mexico on the efficiency of FTWs in removing microplastics in urban water bodies.

Determination of Phenolic, Flavonoid Content and Antioxidant Activity of Oil Rose Products

Rose and rose products are used as raw materials in many sectors including cosmetics, food and medicine. The Rosa damascena Mill. rose genotype, which is intensively cultivated in the Isparta region of Türkiye, is an important export product. The flower of the plant is main source of raw materials for rose oil, herbal teas and cosmetic products due to its high essential oil and polyphenols contents. In this study, Rosa damascena, Rosa centifolia, Rosa alba L., Rosa alba ‘Semiplena’ genotypes were grown in Yalova, which is an alternative region in terms of agro-climatic conditions from Isparta and its surroundings where rose oil cultivation is carried out in Türkiye. Within the scope of the study, total phenolic matter, total antioxidant activity (DPPH and CUPRAC) and total flavonoid contents of flowers (whole flowers), rose water and wastewater of the genotypes were determined. It is important to identify alternative rose genotypes to R. damascena in Türkiye and their potential for cultivation under different climatic conditions. The highest phenolic content (4115 mg gallic acid equivalent GAE 100 g-1) and DPPH antioxidant activity (4893 mg trolox equivalent TE 100 g-1) values were obtained in R. damascena genotype at the first harvest period. The highest CUPRAC antioxidant activity (34237 mg TE 100 g-1) values were obtained in R. centifolia genotype at the first harvest period. In the second harvest period, the highest phenolic content, DPPH antioxidant activity and CUPRAC antioxidant activity values were determined in R. centifolia genotype. Antioxidant activity, phenolic and flavonoid contents of dried rose flowers were higher than in rose water and wastewater. Rose petals were found to have the potential to be used as an important antioxidant source, while total phenolic matter and antioxidant activity values were found to be low in rose water and wastewater. The harvest period was found to be major factor in oil rose flowers, which can be an important polyphenol source.

IMPLEMENTASI SISTEM CERDAS PENGENDALI HAMA BURUNG PADA TANAMAN PADI DI LINGKUNGAN INTEGRATED MULTI-TROPHIC AQUACULTURE (IMTA)

Birds are one type of pest that worries many rice farmers when they enter the harvest period. During the harvest period, farmers start to get busy again with activities to protect their crops so that birds don't eat them. Efforts made by farmers to repel bird pests are still carried out conventionally, namely by tying ropes to poles and making scarecrows which are moved by farmers. If birds enter the rice fields, this is deemed less effective and efficient. As a follow-up to this problem, this research aims to help farmers protect rice plants from bird pests during the pre-harvest season. This intelligent system was built using laser sensors and can automatically detect and control bird pests. This laser beam is reflected by mirrors installed on both sides of the rice field. This mirror is used to reflect laser light to detect the presence of bird pests and send data to the ESP8266 MCU node to instruct the AC motor to pull the tassel rope to repel bird pests. Based on the research results, this tool has been implemented at IMTA so that this tool can be used to detect the presence of bird pests and control bird pests so that it can be used as an effort to control bird pests. Apart from that, monitoring the work of this tool system can be done remotely via the website.

Exogenous regulation of macronutrients promotes the accumulation of alkaloid yield in anisodus tanguticus (Maxim.) pascher

BackgroundAnisodus tanguticus (Maxim.) Pascher (A. tanguticus) is a valuable botanical for extracting tropane alkaloids, which are widely used in the pharmaceutical industry. Implementing appropriate cultivation methods can improve both the quality and yield of A. tanguticus. A two-year field experiment was conducted from 2021 to 2023 using a single-factor randomized complete block design replicated three times. The study examined the effects of different nutrient levels (nitrogen: 0, 75, 150, 225, 300, 375 kg/ha; phosphorus: 0, 600, 750, 900, 1050, 1200 kg/ha; potassium: 0, 75, 112.5, 150, 187.5, 225 kg/ha) on the growth, primary alkaloid contents, and alkaloid yield of A. tanguticus at different growth stages (S-Greening, S-Growing, S-Wilting; T-Greening, T-Growing, and T-Wilting) in both the roots and aboveground portions.ResultsOur results demonstrate that nutrient levels significantly affect the growth and alkaloid accumulation in A. tanguticus. High nitrogen levels (375 kg/ha) notably increased both root and aboveground biomass, while phosphorus had a minimal effect, especially on aboveground biomass. For alkaloid content (scopolamine, anisodamine, anisodine, atropine), a moderate nitrogen level (225 kg/ha) was most effective, followed by low potassium (75 kg/ha), with phosphorus showing a limited impact. Increased phosphorus levels led to a decrease in scopolamine content. During the T-Growing period, moderate nitrogen addition (225 kg/ha) yielded the highest alkaloid levels per unit area (205.79 kg/ha). In the T-Wilting period, low potassium (75 kg/ha) and low phosphorus (750 kg/ha) resulted in alkaloid levels of 146.91 kg/ha and 142.18 kg/ha, respectively. This indicates nitrogen has the most substantial effect on alkaloid accumulation, followed by potassium and phosphorus. The Douglas production function analysis suggests focusing on root biomass and the accumulation of scopolamine and atropine in roots to maximize alkaloid yield in A. tanguticus cultivation.ConclusionsOur findings show that the optimum harvesting period for A. tanguticus is the T-Wilting period, and that the optimal nitrogen addition is 225 kg/ha, the optimal potassium addition is 75 kg/ha, and the optimal phosphorus addition is 600 kg/ha or less.

ANALYSIS OF RICE PRICE FORMATION AND INCREASE AT THE FARMER LEVEL

<p>This study aims to determine and analyze the condition of farmers, increasing and determining rice prices at the farmer level in German Village, Sugio District, Lamongan Regency. This study used a qualitative approach with data collection methods by conducting interviews. The results of this study show that German Village is a village with high agricultural sector potential due to rainfed areas. In addition, irrigation facilities and agricultural equipment in German Village are very adequate. Furthermore, the average German Village farmer has a land area above 5,000 m2 with a harvest period of 4 months and can harvest 3 times a year. Next, in rice pricing, the role of middlemen is very large. Meanwhile, there are four ways to increase rice prices, including: selling crops through social media, price monopoly by farmers, agricultural socialization, and scheduling harvest and planting seasons.</p>

Functional and pasting properties of aerial yam starch at different harvesting periods

The impact of the harvesting period (sixth, seventh and eighth month) on functional and pasting properties of starches from Tob2857 and Tob3059 cultivars of aerial yam was investigated. Matured yam bulbils were further classified into two; matured ripe bulbils (MRB) and matured unripe bulbils (MUB) based on their peel colours at harvest. Starch content, amylose, resistant starch (RS), pasting and morphological characteristics of starches were evaluated using standard methods. RS (5.11-12.37%), amylose (14.88-20.15%) and solubility (1.16-3.98%) were higher in MUB than MRB starches and varied with the harvesting period. Pasting profiles revealed that peak, hot, break down, cold paste and set back viscosities, respectively ranged thus; (261.50-528.92 RVU), (269.00-458.38 RVU), (16.95-70.54 RVU), (304.14-576.79 RVU) and (71.42-118.41 RVU). Pasting time and temperature ranged from 4.68-5.92 min and 84.18-88.26 oC, respectively. The swelling power (0.53-9.85%) varied significantly between the cultivars and ripeness of the bulbils. The starch granules showed similar shapes (ovo-triangular-oblong) and granule size (16.80-32.34 µm) varied significantly with the harvesting period. The variation in functionality of aerial yam starch cultivars at different harvesting periods in this study could be exploited for the postharvest valorization of aerial yam starches.

The development of honey recognition models with broad applicability based on the association of isotope and elemental content with ANNs

Honey adulteration represents a worldwide problem, driven by the illicit economic gain that producers, traders, or merchants pursue. Among the falsification methods that can unfairly influence the price is the incorrect declaration of the botanical origin and harvesting year. Therefore, the present study aimed to test the potential given by the application of Artificial Neural Networks (ANNs) for developing prediction models able to assess honey botanical origin and harvesting year based on isotope and elemental fingerprints. For each classification criterion, significant focus was dedicated to the data preprocessing phase to enhance the models' prediction capability. The obtained classification performances (accuracy scores >86% during the test phase) have highlighted the efficiency of ANNs for honey authentication as well as the feasibility of applying the developed classifiers for a large-scale application, supported by their ability to recognize the correct origin despite considerable variability in botanical source, geographical origin, and harvesting period.

Tritium Behavior from Vine to Wine

The hydrogen radioactive isotope, tritium, not only reflects seasonal variation in precipitation but also variations on a local level. To use this radioisotope in authentication and geographical indication procedures, the tritium levels in vines, grapes, and wine were measured in two forms: (1) tissue-free water tritium (TFWT), measured in the free water of the plant or the aqueous phase of the wine; (2) organically bound tritium (OBT), measured in the organic part of the plant or wine (as ethanol). This paper presents the tritium behavior in vines from May to October and in the wine produced from harvested grapes for both tritium forms (TFWT and OBT) in connection with environmental tritium concentrations in air and precipitations during the 2019–2023 vegetation periods near the Râmnicu Vâlcea city. If the tritium of tissue-free water was influenced by precipitation and air humidity during the harvest period, the organically bound tritium recorded a maximum level with a delay of 1–2 months compared with tritium’s seasonal variation in precipitation and air. The tritium values of early mean in precipitation and ethanol from wine were approximately an average value of 11 TU for all 5 years of observations.

Spatiotemporal Variabilities in Evapotranspiration of Alfalfa: A Case Study Using Remote Sensing METRIC and SSEBop Models and Eddy Covariance

Prolonged drought exacerbated by climate change in the Mesilla Valley, one of the major agricultural areas of New Mexico, USA, is causing a shortage of surface water from the Rio Grande for irrigation. Farmers in the Valley are using groundwater for irrigation and complementing it with limited surface water from the river (Rio Grande). Managing irrigation water better is vital to sustaining agriculture in the Valley. Remote sensing (RS)-based crop evapotranspiration (ETa) models offer significant advantages over traditional methods. The ET maps generated by these RS models provide valuable information that can be used to manage irrigation water and crops in water-scarce areas. This study used METRIC and SSEBop RS models to map the ET of alfalfa on a private farm that is managed as commonly practiced in the Valley. The integrated ET values of the two models are compared to those of the ETa measured using the eddy covariance method. The comparison showed that 91.55% of the variability in SSEBop ETa estimates can be explained by the variability in the METRIC ETa estimates, and the variability in eddy covariance ETa can explain 93.07% of the variability in METRIC ETa and 86.01% in the SSEBop Eta estimates. Both METRIC and SSEBop reflected the ETa of alfalfa during full growth and harvesting periods. However, the absolute percent mean relative difference (MRD) of ET was higher for two out of three cuttings by SSEBop (>32%) compared to those for METRIC and eddy covariance. The spatiotemporal variabilities in crop ET estimates using METRIC and SSEBop showed a need to improve on-farm irrigation conveyance and on-the-field irrigation efficiency. Overall, RS models can provide spatiotemporal maps of ET that can be used for decision-making to manage irrigation water better and improve crop yield on a field, farm, and regional scale.

Effects of Freeze-Thaw Pretreatment Combined with Hot Air on Snake Gourd (Trichosanthes anguina L.).

Snake gourd is a seasonal vegetable with a high water content and medicinal value, but the short harvest period limits the large-scale application of snake gourd. Therefore, the effects of freeze-thaw pretreatment (FT) combined with hot air (HD) on the drying characteristics, active ingredients and bioactivities of snake gourd were investigated. The results showed that FT pretreatment reduced browning and shortened the drying time by 44%; the Page model was the best fit for describing the drying process. The polysaccharide contents (21.70% in alcoholic extract (TG1) and 44.34% in water extract (TG2)) and total phenol contents (1.81% in TG1 and 0.88% in TG2) of snake gourd pretreated by FT-HD were higher than those of snake gourd pretreated by the corresponding HD treatment. The FT pretreatment decreased the molecular weight of snake gourd polysaccharides and increased the molar ratio of glucose. The extracts pretreated by FT-HD showed greater chemical, cellular antioxidant capacity and α-amylase and α-glucosidase inhibition than those pretreated by HD. FT-HD can be recommended for achieving a short drying time and high quality of snake gourd and can be used for the drying of other fruits and vegetables.

Botanical, Chemical, and Pharmacological Characteristics of Carob Tree (Ceratonia Siliqua L)

In Morocco the carob tree (Ceratonia siliqua L.), is scattered in the wild or articificial state throughout the country. It belongs to the Ceasalpiniaceae subfamily of the legume family, is a sclerophyllous, xerophilic, thermophilic, calciclous and heliophilous species. The carob is a Mediterranean medicinal plant, it is characterized by ecological, socio-economic, industrial and ornamental importance. It is an agro-sylvo-pastoral species that can be used for the rehabilitation of degraded soils, thanks to its capacity to adapt to different edapho-climatic conditions. The most important producing countries are Spain, Italy, Morocco, Portugal, Greece, Turkey and Cyprus. Many factors affect the chemical composition of the fruit as well as its mineral content, for example the temperature, the origin of the cultivar and the harvest period. In therapy, this plant is known for its cholesterol-lowering, antiproliferative, antidiarrheal effect.

Nutrient-feeding strategy promotes the growth, biomass, and quality of genotype/variety CIM Megha of Kalmegh

The current study used two harvesting periods (2020-21 and 2021–2022) to investigate the effects of organic and inorganic fertilizers applied to the soil on Kalmegh growth, productivity, and economic viability. The study looked at a variety of growth parameters, including plant height, the number of primary and secondary branches, plant spread, leaf area, dry matter accumulation, and fresh, dry, and seeded herbage output. T6 (RDF + VAM + Vermicompost) produced much higher growth metrics and yields than other treatments, exhibiting consistently better performance. The improved outcomes were attributed to the combined effects of inorganic fertilizers, mycorrhizal association (VAM), and organic supplementation (vermicompost). T2 (RDF + vermicompost) displayed a similar performance. On the other hand, the T7 control group had the lowest values across all metrics. The economic study determined that T6 was the most economically viable choice due to its higher gross and net returns. This emphasizes the importance of coordinated nutrient management in achieving optimal agricultural output and economic sustainability. According to the study's findings, T6, which has a balanced mix of inorganic and organic amendments, is a promising technique for increasing kalmegh variety CIM Megha production. This technique provides higher crops, financial rewards, and improved soil nutrient levels.

Utilizing Biostimulator Grow–B for Increasing Tobacco Seeds Germination, Biometric Indicators of Seedling and Quality of Cured Tobacco

In 2020–2021, in the central zone of the Krasnodar Territory, a study was conducted on the effectiveness of a biostimulator based on triterpene acids Grow–B on tobacco of the promising variety Sheptalsky 63. According to the results of the use of a growth-stimulating agent with a fungicidal effect in laboratory conditions, it was found that pre-sowing soaking of tobacco seeds at a concentration of 0.05% for 6 hours increased the weight of tobacco seedlings by 43%. Sowing of treated tobacco seeds in a greenhouse together with additional double treatment of seedlings in the development phases “ears” and “fit for planting” with a solution of the biostimulator Grow–B in a concentration of 0.05% increased the number of leaves on plants by 18, the length of seedlings from the root neck to the point of growth – by 37, to the end of the elongated leaves – by 24, the diameter of the stem is by 30, the crude mass of the aboveground part and the root system is by 96 and 95%, respectively. The yield of standard seedlings per unit of greenhouse area increased by 29%. The survival rate of plants in the field reached 98, their height increased by 12 by the end of the harvesting period, the area of tobacco leaves of the middle tier – by 28, yield – by 37% compared with the control. Pre-sowing soaking of seeds and seedling treatment with the Grow–B biostimulator increased the amount of nicotine in tobacco raw materials by 34, carbohydrates by 68, and reduced the amount of proteins by 13%. The number of Schmuck (carbohydrate-protein ratio characterizing the quality of raw materials) increased by 89% against the background of a biostimulator.

Fertilizer Effects on the Nitrogen Isotope Composition of Soil and Different Leaf Locations of Potted Camellia sinensis over a Growing Season.

The nitrogen-stable isotopes of plants can be used to verify the source of fertilizers, but the fertilizer uptake patterns in tea (Camellia sinensis) plants are unclear. In this study, potted tea plants were treated with three types of organic fertilizers (OFs), urea, and a control. The tea leaves were sampled over seven months from the top, middle, and base of the plants and analyzed for the δ15N and nitrogen content, along with the corresponding soil samples. The top tea leaves treated with the rapeseed cake OF had the highest δ15N values (up to 6.6‱), followed by the chicken manure, the cow manure, the control, and the urea fertilizer (6.5‱, 4.1‱, 2.2‱, and 0.6‱, respectively). The soil treated with cow manure had the highest δ15N values (6.0‱), followed by the chicken manure, rapeseed cake, control, and urea fertilizer (4.8‱, 4.0‱, 2.5‱, and 1.9‱, respectively). The tea leaves fertilized with rapeseed cake showed only slight δ15N value changes in autumn but increased significantly in early spring and then decreased in late spring, consistent with the delivery of a slow-release fertilizer. Meanwhile, the δ15N values of the top, middle, and basal leaves from the tea plants treated with the rapeseed cake treatment were consistently higher in early spring and lower in autumn and late spring, respectively. The urea and control samples had lower tea leaf δ15N values than the rapeseed cake-treated tea and showed a generalized decrease in the tea leaf δ15N values over time. The results clarify the temporal nitrogen patterns and isotope compositions of tea leaves treated with different fertilizer types and ensure that the δ15N tea leaf values can be used to authenticate the organic fertilizer methods across different harvest periods and leaf locations. The present results based on a pot experiment require further exploration in open agricultural soils in terms of the various potential fertilizer effects on the different variations of nitrogen isotope ratios in tea plants.

GROWTH AND YIELD OF BRAZILIAN SPINACH UNDER DIFFERENT SHADING INTENSITIES AND HARVESTING PERIODS IN A TROPICAL LOWLAND URBAN ECOSYSTEM

Brazilian spinach (Alternanthera sissoo) is a less prominent perennial leafy vegetable growing in the tropical ecosystem. Therefore, this research aimed to investigate the effects of different shading intensities and harvesting periods on the growth and yield of Brazilian spinach in a tropical lowland urban ecosystem. The investigation used a split-plot design, with different shading intensities (no-shading, 45%, 55%, and 80% shading) as the main plot and harvesting periods (every 2, 3, and 4 weeks) as the subplot. The results showed that Brazilian spinach growth was significantly enhanced under no-shading conditions compared to shading treatments. Furthermore, 80% shading negatively impacted plant growth during early stages, as evidenced by alterations in parameters including canopy area (26.47 cm2), diameter (7.98 cm), and index (0.52), as well as Soil Plant Analysis Development (SPAD) values. This led to reduced branch elongation, marketable yield (14.76 g), and non-marketable yield (4.68), along with a decreased dry weight of stems (0.25 g), branches (0.40 g), leaves (0.85 g), and roots (0.44 g). However, marketable leaves from unshaded plants had higher carbon content (34.64%) and lower nitrogen content (2.83%). More frequent harvesting every 2 weeks elevated marketable yield (67.22 g) but suppressed the growth of stems (1.05 g), branches (4.39 g), and roots (1.73 g). Based on these observations, the cultivation of Brazilian spinach in unshaded areas with a biweekly harvesting routine was recommended