AGRI-ENVIRONMENTAL SCIENCES

EVALUATION OF THE EFFECT OF MICROALGAL EXTRACT (Chlorella sp.) ON THE GERMINATION OF CRISP LETTUCE SEEDS (Lactuca sativa L.)

Mon, 27 Apr 2026 00:00:00 -0300

The use of microalgae as agricultural biostimulants has gained increasing attention due to the presence of bioactive compounds capable of influencing plant physiological processes. This study aimed to identify and characterize microalgal communities from urban aquatic environments, develop a selective cultivation method, and evaluate the effect of an aqueous extract of Chlorella sp. on the germination of crisp lettuce (Lactuca sativa L.) seeds. Samples were collected from four sites in Lago de Palmas (Tocantins, Brazil), where 28 microalgal species were identified, with qualitative and quantitative variations associated with the degree of environmental eutrophication. Selective cultivation was optimized using different concentrations of NPK (10-10-10), with $1\ \text{g L}^{-1}$ providing the most favorable conditions for Chlorella sp. growth. The resulting aqueous extract was applied in germination assays under controlled conditions to assess germination percentage (%G), germination speed index (GSI/IVG), and mean germination time (MGT/TMG). After 12 days, seeds treated with the microalgal extract showed a significant increase in germination compared to the control. This effect was most pronounced when the extract was applied via reapplication, resulting in higher %G and GSI and lower MGT. Conversely, prolonged seed immersion in the extract negatively impacted germination speed. These findings indicate that the aqueous extract of Chlorella sp. acts as an effective plant biostimulant, though its efficacy is strictly dependent on the mode of application, highlighting the potential of microalgae as a sustainable alternative for modern agriculture.

SOYBEAN SEED QUALITY IN RESPONSE TO CHEMICAL AND BIOLOGICAL SEED TREATMENTS

Mon, 27 Apr 2026 11:03:42 -0300

Seed treatment is an essential practice to ensure the initial establishment and productive success of soybean (Glycine max L.) crops. This study aimed to evaluate the quality of soybean seeds, cultivar 80I82 RSF IPRO, subjected to seven treatments, including a control, using chemical (Fludioxonil + Metalaxyl-M) and biological agents (Bacillus aryabhattai; B. amyloliquefaciens; B. paralicheniformis; B. velezensis + B. amyloliquefaciens; Trichoderma harzianum), based on emergence tests. Two emergence tests were conducted, one in sand and the other in lowland soil, evaluating seedling emergence, emergence speed index (ESI), and vigor. The treatment with Fludioxonil + Metalaxyl-M showed a high germination rate (90%), high vigor (82%), and a lower incidence of abnormal seedlings (6%) in the soil emergence test. Under the same conditions, biological treatment with Bacillus amyloliquefaciens resulted in high germination (87%), high vigor (83%), and a low percentage of abnormal seedlings (5%). In contrast, treatment with Trichoderma harzianum was the least efficient, resulting in the lowest values in emergence tests, both in sand and soil. Seed treatment with Bacillus amyloliquefaciens demonstrated potential for use without negatively affecting the physiological quality of soybean seeds.

STRUCTURAL ECONOMIC ANALYSIS AND PREDICTIVE MODELING OF FISH FINGERLING PRODUCTION IN BRAZIL: A MULTIVARIATE INVESTIGATION BASED ON THE IBGE/SIDRA DATABASE (2013–2023)

Murilo Henrique Tank Fortunato, Karoline Moreira Barbuio — Mon, 27 Apr 2026 11:22:16 -0300

Fingerling production, the breeding and commercialization of young fish, constitutes the primary biological and financial link in Brazilian fish farming. This study aims to dissect the economic structure of this sector using a Data Science approach applied to Table 3940 from the SIDRA/IBGE system. Through a rigorous analytical protocol integrating Exploratory Data Analysis (EDA), Partition-Based Clustering (K-means), and Multiple Linear Regression with regional error correction, the article demonstrates that value formation in the sector is governed by a pronounced dichotomy between large-scale operational efficiency and the economic valuation of regional niche markets. The study concludes that the long-term sustainability of the sector depends on correcting pricing asymmetries in the Northeast region and maintaining productive stability in the Center-South of Brazil.

The THE PHYSIOLOGICAL EFFECT OF THE PLANT GROWTH REGULATOR 2,4-D ON LEAVES AND FRUIT OF SWEET ORANGE AFFECTED BY CITRUS CANKER

Mon, 27 Apr 2026 16:28:19 -0300

Citrus canker, caused by Xanthomonas citri subsp. citri (Xcc), is a highly destructive disease that significantly reduces both yield and fruit quality. The pathogen infects young leaf tissues, fruits, and shoots of susceptible citrus plants, often leading to severe defoliation and premature fruit drop. The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is a synthetic auxin used at specific concentrations to mitigate citrus fruit drop. This study aimed to evaluate the in vitro effect of 2,4-D at various concentrations (0, 0.15, 0.30, 0.45, 0.60, and 0.75 mg i.a. L-1) on Xcc colonies, and to assess its impact on the lesion diameter of citrus canker on detached leaves of sweet orange (Citrus sinensis). Leaves were sampled 21 days after application (DAA) of 2,4-D at concentrations of 0, 0.20, 0.50, and 0.80 mg i.a. L-1. Additionally, the activity of soluble peroxidase was determined at 2, 7, and 14 DAA. Field trials were conducted to evaluate the development of citrus canker on leaves and the fruit detachment force required to remove fruit from the peduncle under the same concentration gradient. Results indicated that no 2,4-D concentration tested in vitro significantly affected Xcc colony-forming units (CFU). However, the mean lesion diameter on detached leaves and peroxidase activity decreased progressively with increasing concentrations of 2,4-D. While field observations showed a modest reduction in leaf lesion development, no significant impact was observed on the fruit detachment force. We conclude that although 2,4-D demonstrates potential in reducing the severity of citrus canker lesions, it does not significantly mitigate defoliation or fruit drop in field conditions at the tested concentrations.ncentrations.

DEVELOPMENT AND EVALUATION OF A MIXED PITAYA AND PINEAPPLE JELLY ENRICHED WITH PITAYA PEEL FLOUR

Tue, 28 Apr 2026 12:21:38 -0300

Pitaya (Hylocereus undatus) and pineapple (Ananas comosus L. Merril) show high technological potential for the development of innovative products, such as mixed jams. Thus, the present study aimed to formulate and characterize, from a physicochemical and sensory perspective, different formulations of mixed pitaya and pineapple jam produced using the whole pitaya, including the use of peel flour. Two jam formulations were prepared containing pineapple and pitaya pulp, sugar, pectin, and citric acid. In the control formulation (F1), pitaya peel flour was not added, whereas in formulation F2, pitaya peel flour was included. The following parameters were determined: pH, total soluble solids (°Brix), titratable acidity, color, microbiological analyses, and sensory evaluation with untrained panelists using hedonic scales and purchase intention tests. The physicochemical results indicated that both formulations presented pH, °Brix, and acidity values within the regulatory standards for fruit jams, demonstrating adequate stability and preservation. Microbiological analyses confirmed the safety of the products. Colorimetric evaluation revealed that the addition of pitaya peel flour significantly influenced color parameters, promoting greater chromatic intensity. Sensory analysis showed high acceptance for both formulations. It is concluded that the use of pitaya peel in flour form is technically feasible and sustainable, although formulation adjustments are necessary to optimize sensory acceptance and the commercial viability of the product.

UNCOVERING THE ANTIOXIDANT AND ANTIMICROBIAL POTENTIAL OF NON-CONVENTIONAL EDIBLE PLANTS COMMONLY FOUND IN BRAZIL

Tue, 28 Apr 2026 12:23:12 -0300

Brazil, one of the most megadiverse countries, is home to numerous non-conventional edible plants (NCEP), whose functional applications are underexplored. This review highlighted the antimicrobial and antioxidant properties of Schinus terebinthifolius Raddi (pink pepper), Pereskia aculeata Miller (ora-pro-nóbis), and Tropaeolum majus L. (nasturtium). A literature review was conducted to identify key findings, bioactive compounds, extraction methods, gaps and challenges that affect the consistency of the results. The literature review covered studies published between 2012 and 2025, identified through keyword searches in scientific databases. Studies focusing on essential oils, undergraduate theses, dissertations, doctoral theses, and conference abstracts were excluded. After applying these criteria, a total of 45 studies were included in the final analysis. While antioxidant activity is consistently supported across various assays, antimicrobial evidence for P. aculeata and T. majus is often limited or inconclusive, despite frequent citations in the literature. There is a clear need to detailed compound profiling to establish correlations between biological activity and the specific metabolites responsible for such effects. Despite limitations, promising results support the potential of these plants for future applications in the food and pharmaceutical industries. By consolidating current findings and highlighting research limitations, this review provides a valuable resource to support and guide future investigations into the functional applications and bioactive constituents of NCEP.