ABSTRACT: The success of soybean cultivation depends on high physiological seed quality, which can be affected by increasing slurry complexity in industrial seed treatment (IST). This study evaluated the effects of slurry application volume (SAV; 9 to 18 mL.kg⁻¹) and mixture composition, including pesticides, biological inputs, and physical additives (polymer and drying powder) on hydration dynamics, seed coat integrity, and physiological performance of soybean seeds (genotype 64i61 IPRO). Results showed that SAV establishes a biophysical stress gradient, with a practical safety threshold around 12 mL.kg⁻¹. Above this level, rapid water uptake was associated with increased microcrack incidence and reductions in seed vigor. At 18 mL.kg⁻¹, the base slurry without physical additives reduced the percentage of strong seedlings from 85.7% in the untreated control to 64.3%, whereas the addition of polymer, either alone or combined with drying powder, maintained values above 82%. Hydration analyses indicated that initial water gain is a key determinant of physiological damage, reinforcing the role of additives in modulating imbibition kinetics. These findings demonstrate that managing slurry volume and additive composition is essential for maintaining seed quality under complex IST systems. Additionally, early indicators such as initial seed water content and microcrack incidence provide a reliable basis for predicting physiological performance and supporting industrial quality control.
ABSTRACT: Subtilases (SBTs) are serine proteases widely distributed in plants and involved in multiple developmental and stress-related processes; however, their roles in legume seeds remain poorly characterized. In this study, SBT activity in soybean (Glycine max) seeds during germination and seed development was investigated using an in vivo staining method based on hydrolysis of the synthetic substrate Suc-AAPF-pNA and diazotization of released p-nitroaniline. This approach, previously validated in cereals, was found to be fully applicable to legume seeds. SBT activity was detected in both cotyledons and seed coats during germination, with a marked increase in the cotyledons at day 3 and in the emerging radicle already at day 2. Enzymatic assays in soluble extracts confirmed the enzymatic nature of substrate hydrolysis. During seed development, the highest SBT activity was localized in the seed coat at early developmental stages (R5.1), remaining detectable through later stages and into germination. These findings indicate that SBTs are active throughout soybean seed development and early seedling growth. Activity detected in the seed coat during germination likely reflects residual enzymes synthesized during development, potentially contributing to protective functions. Conversely, SBTs active in the cotyledons and radicle are likely synthesized de novo and may support reserve mobilization and early seedling growth.
ABSTRACT: This study aimed to determine seed germination characteristics of citron (Citrus medica) and improve its germination. Citron was used as materials to observe its characters. Effects of seed coat removal, seed size and fruit maturity on citron seed germination were investigated. The findings indicated that the average normal seed weight was found to be 0.110 g while small 0.037 g; citron seed have ovoid shape (93.7%), spheroid (3.3%), and semi-deltoid (3.0%); seed percentage was 1%. After seed coat was removed, days taken to initial germination of citron seed were shortened by 5.6 d while germination percentage and germination potential and germination speed index of seeds significantly increased by 4.9%, 6.0% and 0.37, respectively. No significant differences taken to initial germination and germination potential were found between small and normal seed, but germination percentage and germination speed index of small seed was significantly lower than that of normal seed by 13.0% and 10.4, respectively. Early and immature fruit harvest with greenish-yellow skin had no significant impact on seed germination. The findings of this study will serve as a valuable reference for seed propagation strategies for C. medica.
ABSTRACT: Seed longevity refers to the ability of a seed to preserve viability and vigor throughout storage. However, early loss of quality during storage is still frequently observed in soybean seed lots, constituting one of the main challenges of the production chain in tropical environments. This review details longevity as a property with a strong intrinsic influence and not determined exclusively by storage conditions. The intrinsic factors associated with longevity and the processes by which this attribute is progressively established throughout development are discussed, based on the interaction between genotype, environment and management. The review redefines the concept of maximum physiological quality associated with the point of physiological maturity and repositions late maturation as a physiologically active phase, marked by metabolic, structural and molecular adjustments related to the acquisition of longevity of soybean seeds. Additionally, it is proposed to update the reproductive scale of soybean for seed production, integrating the sequential order of acquisition of physiological quality attributes. This review offers an integrated interpretation for the variability observed among soybean seed lots, contributing to the improvement of field management and to greater predictability of seed performance during storage.
ABSTRACT: Herbicide applications during field production may affect crop performance even in genetically tolerant cultivars. Among the potential effects, impacts on seed physiological quality particularly under seed production systems-remain poorly understood. The objective of this study was evaluate the effects of post-emergence herbicide applications at different reproductive stages on the physiological quality and storability of Enlist® soybean seeds, tolerant to glyphosate, 2,4-D and ammonium glufosinate. A field trial was conducted using a randomized complete block design with three replications in a 3 × 5 + 1 factorial scheme: three herbicides (glyphosate, 2,4-D and ammonium glufosinate) applied at five reproductive stages (R2, R4, R5, R6 and R7), plus an untreated control. Seed quality was evaluated using germination, accelerated aging and electrical conductivity tests, conducted both before and after 6 months of storage. Applications of these herbicides in the early reproductive (R2 and R4) resulted in less deterioration of seed physiological quality, whereas later applications (R5 and R7) were associated with significant quality deterioration deterioration, even in tolerant cultivars. These findings underscore the critical importance of proper herbicide timing to safeguard seed vigor and enhance storability in herbicide-tolerant soybean systems.
ABSTRACT: Cenostigma pyramidaleis an endemic Caatinga species, and plays an important role in ecological restoration, but seedling production in semi-arid nurseries is constrained by water deficit and the use of brackish irrigation water. This study evaluated germination, seedling emergence, and early growth ofC. pyramidaleseedlings obtained from seeds harvestedin three populations from the Caatinga, subjected to hydropriming and grown under irrigation with non-saline tap water or brackish groundwater. Seed physiological quality and imbibition patterns were assessed to define population-specific priming protocols (hydropriming, HD). The experiment followed a completely randomized design in a 2 × 2 × 3 factorial scheme, with four replications of 25 seeds, considering the factors: HD cycles, irrigation water quality, and seed lots. After 90 days in the nursery, seedlings irrigated with tapwater showed better growth, whereas brackish water reduced performance in all populations. Hydropriming increased emergence under salinity but did not improve subsequent seedling growth. Differences among populations indicate intrinsic variation in vigor and stress response.
ABSTRACT: Pre-harvest desiccation of soybean using herbicides aims to advance harvest and reduce seed deterioration after physiological maturity. However, certain products may compromise seed physiological potential from harvest through storage. This study aimed to evaluate the effects of pre-harvest desiccation of soybean plants with different herbicides on seed physiological quality. The experiments were conducted in Apucarana, Paraná and Mauá da Serra, Paraná, Brazil, using the following treatments: control (no herbicide application), Diquat; Glufosinate Ammonium; Carfentrazone; Atrazine; Saflufenacil; [Glufosinate Ammonium + Carfentrazone], and Tiafenacil. The evaluated variables included plant water content, seed moisture loss, thousand-seed weight, and yield, as well as first germination count, germination, seedling length and dry mass, accelerated aging, emergence, and peroxidase and catalase activity. The use of Diquat and Tiafenacil allowed harvest to be advanced by up to eight days while maintaining seed physiological quality in both locations, even after storage. In Apucarana, the application of Saflufenacil, Carfentrazone, Glufosinate Ammonium, and Glufosinate Ammonium + Carfentrazone compromised seed physiological quality both at harvest and after storage. Atrazine allowed harvest to be advanced without impairing seed quality. In Mauá da Serra, although all treatments showed high germination, Glufosinate Ammonium and its combination with Carfentrazone reduced seed vigor after storage, indicating negative effects on seed longevity. Overall, pre-harvest desiccation was effective in advancing harvest; however, its effects on seed physiological quality depend on the herbicide used.
ABSTRACT: Thermoinhibition of lettuce seeds causes losses in seedling production. Priming improves seed performance under stress; however, there are gaps regarding the duration of its effects after drying and storage, as well as methods that preserve tolerance to thermoinhibition. The objective of this study was to evaluate biofortified lettuce seeds subjected to priming, different drying methods and storage periods, in order to identify strategies that maintain the effects of the treatment. Seeds of the UFU 189#2#2#1 genotype were osmoprimed in PEG 6000 (-1.2 MPa) and subjected to the following methods: control, priming without drying (PRM), slow drying (SD), fast drying (FD), thermal shock followed by SD (TSSD) or FD (TSFD), and reduction of moisture content followed by SD (rSD) or FD (rFD). Drying was carried out at 25 °C (slow) and 32 °C (fast) for 48 hours. The seeds were stored for 0, 30 and 60 days. In a second trial, SD, FD, rSD, and rFD were evaluated for 12, 24, 36, and 48 hours. Moisture content, first germination count, germination, emergence, germination and emergence speed indices, and dry mass of seedlings were determined. Slow drying is more efficient in preserving the tolerance to thermoinhibition after storage. Tolerance is maintained after reduction of moisture content followed by SD or FD for up to 12 hours, with fast drying also being feasible up to 24 hours.
RESUMO: O condicionamento é uma estratégia para melhorar a germinação, a uniformidade do lote e o vigor das sementes, sendo essencial para espécies como Guazuma ulmifolia utilizadas na restauração florestal. O uso de agentes condicionantes pode promover a germinação e ativar a resposta antioxidante. Este estudo avaliou os efeitos do condicionamento na germinação, emergência e metabolismo oxidativo de sementes de G. ulmifolia, bem como o impacto do armazenamento na viabilidade. O experimento foi conduzido em delineamento inteiramente casualizado com seis tratamentos: controle, hidrocondicionamento, ácido giberélico (GA₃), nitroprussiato de sódio (SNP), nitrato de potássio (KNO₃) e extrato aquoso de fumaça (ASE). Foram analisadas a atividade das enzimas antioxidantes (SOD e CAT) e os níveis de MDA e H₂O₂, e a viabilidade foi monitorada durante 12 meses de armazenamento. Os tratamentos com GA₃, SNP, KNO₃ e ASE aumentaram a germinação e a emergência, sendo o GA₃ o que mais reduziu o tempo para o estabelecimento das plântulas. O aumento da atividade de SOD e a redução do MDA indicaram menor degradação das membranas e maior proteção contra o estresse oxidativo. No entanto, o armazenamento pós-condicionamento não foi viável, sendo recomendado o uso imediato das sementes. Assim, o condicionamento melhora a germinação e a qualidade fisiológica de G. ulmifolia.
ABSTRACT: Ziziphus lotus (L.) Lam. is one of the species targeted by restoration programs aimed at combating desertification. It is characterized by pronounced seed dormancy which limits its natural regeneration. This study aims to evaluate the effectiveness of various treatments to break this dormancy in freshly harvested seeds and those that have matured naturally. Seeds were divided into two lots: one was stored in a freezer (-18 °C) and the other was stored at room temperature for 12 months. The seeds underwent several pretreatments. The results showed that natural post-ripening caused a gradual change in seed color from yellow beige to dark brownish black. This color change was strongly related to the germination rate which increased from 28% (freshly harvested seeds) to 80% (post-ripened seeds, p < 0.001). The most effective treatments for dormant seeds were a combination of cold stratification and soaking in GA3 74%, followed by cold stratification 70%, soaking in water for 72 hours 67% and soaking in GA3 64%. However, post-ripened seeds had a significantly higher germination rate particularly when soaked in water for 48 hours 94%. The remarkable dormancy of these seeds is physiological in nature and their natural post-ripening is the key factor in breaking it.
ABSTRACT: Seed priming improves the seed germination in various crops, including okra. In this study, Gibberellic acid (GA3) (12.50, 25, and 50 ppm), calcium chloride (CaCl2 at 3000 and 6000 ppm), and hydropriming were applied to okra (cv Smooth Green) by priming the seeds for 3 h. It was conducted to evaluate the stimulation effect of seed priming methods on the seedling vigor of okra. Seeds without priming served as the control. Ambient conditions, with a temperature of 29 ± 5 °C and a relative humidity of 65 ± 5%, were maintained, along with a photoperiod of 10h/14h (light/dark). A Completely Randomized Design with four replications was used in the study. Standard germination, germination index, mean germination time, chlorophyll content, seedling length, fresh and dry weights of seedling, secondary root count per seedling, and seedling vigor were gathered. GA3 and CaCl2 improved germination, resulting in more than 85% germination and a faster germination rate compared to unprimed seeds. Moreover, at 21 days after sowing (DAS), GA3 (25 ppm) and CaCl2 (3000 and 6000 ppm) produced longer seedlings. However, CaCl2 outperformed the other priming methods and unprimed seeds in its root count per seedling and seedling fresh weight. GA3 (50 ppm) and CaCl2 (3000 ppm) displayed heavier seedling dry weight and vigorous seedlings. CaCl2 influenced the chlorophyll by obtaining a higher content. Thus, to obtain vigorous seedlings, either GA3 (50 ppm) or CaCl2 (3000 ppm) is recommended.
Forage peanut is an important crop for animal feed; however, seed dormancy hinders field establishment. This study aimed to identify effective methods to overcome seed dormancy and improve germination. The experiment was conducted in a factorial design with three dormancy-breaking methods (ultrasound, gibberellic acid, and ethephon), three ultrasound exposure times (10, 15, and 20 minutes), and three drying periods (3, 6, and 9 days), in addition to a control. Germination, seedling growth, biomass, and enzymatic activity were evaluated. The experimental design was completely randomized. Data were analyzed using ANOVA, followed by the Scott-Knott test (5%) and Dunnett's test, and enzymatic profiles were interpreted using zymograms and the ImageJ software. The most effective treatment was ultrasound for 15 minutes, followed by drying the seeds at 50 degrees C for 9 days, which increased germination to approximately 60%. Higher concentrations of ethephon caused phytotoxicity, while gibberellic acid showed low effectiveness. Enzymatic profiles varied among treatments; the highest alpha-amylase and esterase activities in the ultrasound treatments indicated greater mobilization of seed reserves.
ABSTRACT: Coffee seeds are classified as intermediate, tolerating partial desiccation but being sensitive to low temperatures. They can be stored under cold conditions, allowing only short-term conservation. Cryopreservation overcomes these limitations, providing a viable method for long-term seed conservation and greater flexibility in seedling production. This study aimed to evaluate the development of coffee seedlings from cryopreserved seeds, comparing them with seedlings from seeds stored under cold (10°C) and dry (50% relative humidity) conditions. Seeds of the ‘Catuaí Amarelo’ IAC 62 cultivar were harvested at 42% moisture content (wet basis, wb) and subjected to four treatments: drying in a stationary dryer to 12% (S1) or 32% (S2) wb and stored in cold conditions; drying to 17% wb in saturated NaCl solution (S3) or silica gel (S4) and stored in liquid nitrogen. After six months, germination and tetrazolium tests were performed to assess physiological quality. Seeds were then used for seedling production in a nursery and greenhouse, where height, shoot diameter, number of leaves, leaf area, and shoot and root dry weight were evaluated. S1, S2, and S4 seeds showed similar results across most physiological variables, while S3 consistently exhibited lower performance. Overall, seedlings grown in the greenhouse exhibited greater vegetative development than those produced in the nursery.
Rapid tests are essential for assessing the physiological quality of seeds, especially in native Caatinga species that remain little studied. Cnidoscolus quercifolius (Pohl) has ecological and socioeconomic importance but lacks protocols for determining viability. This study aimed to standardize the tetrazolium test (TZT) for evaluating C. quercifolius seeds. Three seed lots were used, from Massaroca (BA), Sento S & eacute; (BA), and Petrolina (PE). The seeds were preconditioned for 16 h at 30 degrees C on moistened paper and then had the seed coat removed. The experiment followed a completely randomized design in a 7 & times; 4 factorial arrangement, with seven concentrations of 2,3,5 triphenyl tetrazolium chloride (0.025 to 0.75%) and four immersion times (1 to 4 h), with four replications of 25 seeds. Viability was assessed by the intensity and uniformity of carmine-red staining in the embryo and cotyledons. Low tetrazolium chloride concentrations (<= 0.025%) underestimated viability, whereas high ones (>= 0.5%) caused overstaining. Thus, thee range of 0.05 to 0.075% for 3-4 h showed greater diagnostic efficiency, reflecting germination percentages. TZT distinguished viable seeds, with uniform staining and turgid tissues, from non-viable ones. It is concluded that TZT is rapid, reliable, and applicable to programs for conservation, seedling production, and ecological restoration in the Caatinga.
Adenia viridiflora Craib, a native edible climbing plant of northeastern Thailand, has considerable potential as a nutrient-rich indigenous vegetable and a promising agricultural crop. Despite its importance, information on seed propagation and storage responses remains poorly understood. This study assessed five pretreatment methods on germination success: control (untreated), mechanical scarification, hot water, gibberellic acid (GA(3)), and sulfuric acid (98% H2SO4) under two initial seed moisture contents (10-11% and 48-50% RH). Seeds were kept at room temperature (RT), 5 degrees C, and -20 degrees C for a maximum of 14 months to evaluate their longevity. GA(3) pretreatment resulted in the highest germination (>90% in both humidity regimes) with a short mean germination time (12-13 days), and the most synchronized seedling emergence. Hot water moderately improved germination, while mechanical scarification was least effective. Storage tests confirmed orthodox seed behavior. Seed viability remained above 80% for up to 10 months and above 50% after 14 months, with RT and 5 degrees C conditions better maintaining germination potential compared with -20 degrees C. These findings demonstrate that A. viridiflora can be successfully propagated with GA(3) pretreatment and conserved via conventional seed banking. RT storage represents a practical and low-cost option for short- to medium-term conservation, thereby supporting the development of climate-resilient crops and long-term genetic resource preservation.
Yerba mate seedling production is inefficient and costly, as the seeds have slow and low germination (<20%) and are often embryoless. Because the plant is grown in low-fertility soils, particularly in terms of phosphorus, nutritional deficiencies in the mother trees likely contribute to poor seed quality. Therefore, this study investigates the impact of phosphorus fertilization on the seed quality ofyerba mate (Ilexparaguariensis A. St.-Hil.). The experiment was conducted in a seed production area with 1,822 plants, using P2O5 doses of 0, 48, 96, 182, and 288 kg.ha-1. Seed quality was assessed by the 1% tetrazolium test, thousand-seed weight (TSW), and the seed phosphorus content was determined. The results indicated no difference between treatments in seed phosphorus content or 1,000-seed weight, which was 8.0 g. However, seed viability increased with phosphorus application, with the highest quality observed in the 288 kg P2O5 ha-1 treatment. Phosphorus-fertilized mother plants were 2.58 times more likely to produce seeds with embryos. The study demonstrated that phosphorus plays a fundamental role in seed quality, improving viability and embryo presence.
Size is reported for a large range of species as affecting seed quality, being a fast and simple method for selection. Thus, the objective of this work was to evaluate the influence of seed size on the physiological quality of different wheat cultivars. Seeds from 11 wheat cultivars were classified by size: small, medium, and large. Water content, thousand-seed weight, and physiological quality indicators were measured. The results indicated that the physiological quality of wheat seeds is influenced by size; specifically, large size, which is strongly associated with greater seedling length and root and shoot dry matter. While average size correlated with germination rates, initial count, emergence and emergence speed, confirming that seeds of the same size tend to respond similarly to physiological tests. Thus, selecting medium to large-sized seeds can result in higher quality lots, with size being a relevant criterion for obtaining wheat seeds with better physiological performance.
ABSTRACT: Buffelgrass stands out as a key forage species in the semi-arid regions of Brazil, particularly in northern Minas Gerais, due to its capacity to increase pasture productivity and enhance animal performance. Seed viability is traditionally assessed using the tetrazolium test, a reliable but time-consuming and manual method. In this context, computational techniques such as the YOLO framework - a state-of-the-art algorithm for object detection and classification - have shown great potential in seed analysis. This study proposes the classification of buffelgrass seed vigor levels through image-based analysis using version 11 of the YOLO framework. Four seed lots were evaluated through tests of germination, first count, seedling emergence, accelerated aging, and tetrazolium analysis. Mean values were compared using the Tukey test at 5% significance level. In addition, Pearson’s correlation coefficients were calculated among the tests. The seeds were categorized into three vigor levels based on the results obtained from the tetrazolium test, and four classes for training the classification model. For model training, the YOLOv11 algorithm was employed, using digitized laboratory images that underwent feature extraction, balancing, and data augmentation procedures. Model performance was evaluated using top-1 accuracy, as well as analyses of training and validation losses. The model showed excellent performance, achieving 100% accuracy in testing, confirming the potential of this computational approach.
ABSTRACT: Sweet corn seeds have one or more recessive genes that increase the concentration of sugars in the endosperm at the expense of starch, which contributes to greater susceptibility to deterioration. Therefore, it is important to have rapid and automated methods for assessing their physiological potential. This study aimed to evaluate the efficiency of computerized image analysis of seedlings and near-infrared spectroscopy for assessing the physiological potential of these seeds. Seeds from five lots of the sweet corn cultivars Doce Cristal BR-402 and Superdoce BRS-400 were subjected to tests for initial quality characterization. Using the SAPL® software, the shoot, root, and total seedling lengths, as well as the uniformity, growth, and vigor indices, were determined at 3, 4, 5, and 6 days after sowing. Spectra from individual seeds were also collected using an FT-NIR spectrometer, and the same seeds were evaluated by germination test to validate the technique and obtain predictive models through PLS-DA. The preprocessing methods SNV, MSC, and first- and second-order Savitzky-Golay derivatives were applied. The total seedling and root lengths, as well as vigor indices at 3 and 4 days obtained with SAPL®, allowed differentiation of Doce Cristal BR-402 cultivar seed lots according to vigor. For the Superdoce BRS-400 cultivar, root length at 3 days and the uniformity, growth, and vigor indices at 4 days were efficient for this purpose. Data obtained by FT-NIR enabled a rapid and non-destructive estimation of the physiological potential of sweet corn seed lots, especially using the second Savitzky-Golay derivative.
ABSTRACT: The endemic species Diplusodon glaziovii Koehne (Lythraceae) and Barbacenia pungens Mello-Silva (Velloziaceae) are threatened with extinction due to anthropogenic actions in the Rupestrian Grassland ecosystem. In this context, propagation protocols may assist in the conservation of these species. Therefore, this study aimed to understand the germination requirements of D. glaziovii and B. pungens. Four different temperatures were tested, as well as the germinative response of seeds to growth regulators. For D. glaziovii, germination was faster and achieved higher percentages at 25 °C, whereas for B. pungens, it occurred at 30 °C. In D. glaziovii, fluridone (FLU) reduced germination percentage by 30% at the concentration of 150 µM, and paclobutrazol (PBZ) decreased germination speed at 100 µM. In B. pungens, abscisic acid (ABA) reduced germination speed at all concentrations tested, while PBZ decreased both germination percentage and speed by approximately 30% at 150 µM. These results confirm the absence of physiological dormancy in these species and may contribute to their conservation.
