Emergence Speed Research Articles

Effect of chemical and biological seed treatments on common bean seeds inoculated with Fusarium oxysporum f. sp. phaseoli

ABSTRACT: Currently, the common bean (Phaseolus vulgaris L.) productivity has been reduced by the fungus Fusarium oxysporum f. sp. phaseoli (Fop), the causative agent of Fusarium wilt. Considering the integrated management of diseases, the objectives of the present work were to verify the compatibility between chemical and biological fungicides for Fusarium oxysporum Schlecht. f. sp. phaseoli Kendrick & Snyder (Fop) control in common bean seeds. In laboratory, the effects of the treatments were evaluated by sanity, germination, seedling total length and seedling dry matter tests. In greenhouse conditions, the emergence speed rate, the percentage of emergence and the rate of pathogen transmission through the pathogen infestation in a substrate to plants were evaluated. Common bean seeds BRS Estilo were artificially inoculated with Fop isolate (IAC 11.299-1). In the seeds’ treatment, the chemical fungicides fludyoxonyl, flutriafol, methyl tiofanate, and biological products of Trichoderma sp. (isolates SF04, GF 422 and strain 1306), separately and mixed, were used. Treatments that promoted the best pathogen control in seeds were the combination of methyl tiophanate with biological products. Both flutriafol and GF 422 isolated and in mixed treatments affected the seeds’ physiological quality. The protective effect of the products was noted in the transmission test, whose Fop incidence was from 5 to 40% in the hypocotyl and from 5 to 30% in common bean roots.

Impact of storage on the physiological quality of soybean seeds after treatment with fungicides and insecticides

Abstract: Chemical seed treatment is a practice that assists in control of pests and pathogens and allows crops to achieve their maximum yield potential. However, the storage period of seeds treated with insecticides and fungicides can affect seed physiological potential. The aim of this study was to evaluate the physiological quality of soybean seeds treated with different fungicides and insecticides after four different storage periods. The experimental design was completely randomized and the treatments were distributed in a 10 × 4 factorial arrangement in which the soybean seeds of the cultivar BMX Potência RR were treated with the following phytosanitary products: fipronil + pyraclostrobin + thiophanate-methyl, thiophanate-methyl, carbendazim, carboxin + thiram, imidacloprid + thiodicarb, chlorantraniliprole, thiamethoxam, cyantraniliprole, fipronil, and a control (seeds without chemical treatment), in four replications. The seeds were evaluated at 0, 30, 60, and 90 days after the chemical treatment. The following tests were performed: germination, first count of germination, accelerated aging, seedling emergence in sand, seedling emergence speed, and seedling dry matter. The treatment with the carboxin + thiram fungicide mixture provided for adequate physiological quality of the seeds throughout storage. The insecticide thiamethoxam has a negative effect on the physiological quality of soybean seeds that are stored after treatment with it.

Reinvigoration of deteriorated corn seed with wetting and drying technique

With the objective of reinvigorating damaged corn seed, the technique of wetting and drying the seed with five types of water and 10 imbibition times. Estimating the variables emergency percentage, emergency speed, seedling length and root length, and plant height 30 days emergency. For the variable speed of emergency for imbibition time the highest vigor corresponded to 18 and 12h, and with an emergency percentage of 62% higher in 10% of the control, it was 4, 8 and 18h. In water types for emergency percentage, the highest values were observed in artesian well and Key water. In seedling length with values of 25 to 24 cm were distilled water 30h, artesian well 8h y 18h; and the control was 22 cm. In radicle length the highest values corresponded to E. Pure® 24h and key water 14h. For plant height in 8h artesian well present a value of 175 cm, and the control with a value of 165 cm.

EFECTO DE LA FECHA DE SIEMBRA SOBRE LA CALIDAD DE SEMILLA DE TRIGO EN EL BAJÍO, MÉXICO

Seed quality is considered as a pattern that determines field performance or level of deterioration during storage; quality is used as an indicator of the seed value for specific purposes, including those related to distribution and marketing. The aim of this research was to evaluate the physical quality of the seed and the initial vigor of seedling derived from wheat (Triticum aestivum L.) genotypes as influenced by different planting dates. Thirty-six wheat genotypes were established on three planting dates: November 15 and December 15, 2015 and January 15, 2016 at El Bajio Experiment Station of the National Institute of Agricultural, Forest and Livestock Research, located in Celaya, Guanajuato, Mexico. The seeds were subjected to analytical tests for physical quality such as test weight and seed biomass under a completely randomized experimental design; in addition, a test was carried out in sand beds under nursery conditions to assess the initial seedling vigor through emergence speed and emergence percentage, fresh and dry shoot biomass, seedling height and vigor indices I and II using a randomized complete blocks design. There were statistically significant differences for genotypes and planting dates in the registered characters. The interaction genotypes by planting dates significantly modified the physical characteristics and the seedling vigor expressed through the emergence speed, seedling height and vigor index I. The planting date of November 15 was consistent with the highest values in most of the registered characteristics; therefore, it can be considered as the most appropriate planting date to produce quality seed for wheat planting.

EFECTO DE LA FECHA DE SIEMBRA SOBRE LA CALIDAD DE SEMILLA DE TRIGO EN EL BAJÍO , MÉXICO

La calidad de semilla se considera como un patrón que determina el desempeño en el campo o el nivel de su deterioro durante el almacenamiento; la calidad se utiliza como indicador del valor de la semilla con propósitos específicos, inclusive los relacionados con la distribución y comercialización. El objetivo de la presente investigación fue evaluar la calidad física de semilla y el vigor inicial de plántula derivada de genotipos de trigo (Triticum aestivum L.) influenciados por diferentes fechas de siembra. Se establecieron 36 genotipos de trigo en tres fechas de siembra: 15 de noviembre y 15 de diciembre de 2015, y 15 de enero de 2016 en el Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias, Campo Experimental Bajío, localizado en Celaya, Guanajuato, México. Las semillas se sometieron a pruebas analíticas de calidad física como peso volumétrico y biomasa de semilla bajo un diseño experimental completamente aleatorizado; asimismo, se realizó un ensayo en camas de arena bajo condiciones de vivero para evaluar el vigor inicial de plántula a través de velocidad de emergencia, porcentaje de emergencia, biomasa fresca y seca de vástago, altura de plántula e índices de vigor I y II mediante un diseño de bloques completos al azar. Hubo diferencias estadísticas significativas para genotipos y fechas de siembra en los caracteres registrados. La interacción genotipos por fechas de siembra modificó significativamente las características físicas y el vigor de plántula expresado a través de la velocidad de emergencia, altura de plántula e índice de vigor I. La fecha de siembra del 15 de noviembre fue consistente con los valores más altos en la mayoría de las características registradas; por lo que puede ser considerada como la fecha de siembra más apropiada para producir semilla de calidad para siembra de trigo.

FIELD EMERGENCE AND SEEDLING VIGOUR OF BREAD WHEAT AS INFLUENCED BY METHOD AND LONGEVITY OF STORAGE

A laboratory experiment was carried out in the Seed Technology Laboratory, Department of Field Crop Sciences, College of Agricultural Engineering Sciences, University of Baghdad during the period 2010-2019. That was to evaluate bread wheat seeds stored in spikes in their field emergence and seedling vigour. Seeds, of stored spikes were compared with naked seeds, treated with cruise and untreated. All three treatments of seeds were grown in the laboratory and traits of days to last day of emergence, days to emerge, % of emergence, and other trails were recorded. Seeds of stored with thein spikes gave better values in days to last day of emergence, days of emergence, percent of emergence, length of plumule, seedling vigour and speed of emergence. The percent of emergence was decreased with increased years of storage, but those stored in their spikes were less affected. It was concluded that storing bread wheat with spikes had better results in field emergence as compared to seeds threshed and stored.

FRUIT AND SEED MORFOMETRY, SEED GERMINATION AND SEEDLING VIGOR of Parkia gigantocarpa

The objectives of this work were to characterize fruits and seeds and evaluate seed germination and seedling vigor from fifteen parent plants of Parkia gigantocarpa Ducke. The fresh weight, length, width, and thickness of fruits and seeds were determined. The germination was tested in a sand substrate, with four replications of 25 seeds per treatment (parent plants). The number of days for emergence, emergence percentage, emergence speed index, germination percentage, and seedling dry weight were evaluated. The fruits presented means for fresh weight, length, width, and thickness of 115.0 g; 621.3 mm; 60.8 mm, and 9.8 mm, respectively. The seeds presented means for fresh weight, length, width, and thickness of 1.1 g, 22.8 mm, 11.2 mm, and 7.0 mm, respectively. The emergence was fast and uniform, which occurred from the fifth to the sixth day after seeding, reaching 91% germination for the parent HB9, but not differing from the parents HB2, HB3, and HB6. The seedlings from the parents HB2, HB3, HB6, and HB9 were more vigorous due to their higher dry matter accumulation. The results found showed that, even belonging to the same species, P. gigantocarpa seeds from different parent plants present variability in biometric characteristics of fruits and seeds. The seed collected from different parent plants showed differences in germination capacity and seedling vigor.

PHYSIOLOGICAL QUALITY OF MUNG BEAN SEEDS ACCORDING TO THE PLANT DENSITY

Mung beans (Vigna radiata L.) are of Asian origin and have gained national importance with the production of moyashi. The study aimed to evaluate the seed physiological quality of mung beans according to the row spacing and number of plants per meter. The experiment was conducted at Goiás State University, Ipameri Campus. Tests were performed to determine the water content, germination, and vigor to evaluate the physiological quality of the seeds. The experimental design was completely randomized, with the treatments arranged in a 2 x 6 factorial scheme, having as factors the row spacing (25 and 50 cm) and the number of plants per meter (4, 8, 12, 16, 20, and 24 plants) with four replications. Based on the results of the analysis of variance, germination, first germination count, and emergence speed index were not influenced by row spacing and number of plants per meter. The shoot length of seedlings was significative affected by row spacing and the number of plants per meter. For root length, seedling dry mass and thousand-seed weight there was significant interaction between the studied factors. There was significant effect of row spacing on accelerated aging and seedling emergence. The mung bean plant density affected seed quality. Seeds produced with a row spacing of 50 cm with 24 plants per meter had the best physiological potential.

Jatropha curcas seed tolerance to desiccation and storage at low temperatures

Jatropha seeds were classified according to tolerance to desiccation and storage, as a way to subsidize future propagation programs, as jatropha seed shows to be a promising oilseed for biodiesel production. The objective of this work was to study the physiological classification regarding the tolerance of physic nut seeds to desiccation and storage at low temperatures and to verify if their behavior was closer to that of seeds classified as orthodox, recalcitrant or intermediate. The seeds were harvested in the morning and sent to the Laboratory, being processed and submitted to drying, storage and emergency assessment. For seed quality analysis, the germination test and the emergence speed index were used, using a completely randomized design, with four treatments (no drying, 12% humidity, 5% humidity and 12% humidity a -20ºC for 90 days) and five repetitions. After physiological classification, it was found that seeds of physic nut are orthodox, thus can be stored at low temperature (-20ºC) and with low water content (<5%), without compromising their viability.

STRESS CONDITIONS AND ITS EFFECTS ON THE PHYSIOLOGICAL POTENTIAL OF PAPAVER SP. SEEDS

The physiological quality of seeds is commonly characterized by the germination and vigor, which can be defined as the sum of attributes that confers the potential for seeds to germinate, rapidly emerge and result in normal seedlings under a wide range of environmental conditions. The purpose of the study was to test alternative methodologies for the accelerated aging test to evaluate the physiological potential of poppy seeds. Samples obtained from four batches were subjected to germination test at a temperature of 20 °C, traditional accelerated aging and accelerated aging diluted with saline solution (11 g of NaCl in 100 mL-1 of water) using three temperatures, 41 °C, 42 ºC and 43 ºC , for periods of 12 and 24 hours. The percentage of germination, the rate of emergence velocity, performed together with the emergence speed and the percentage of seedling emergence test were evaluated. It is concluded that the methodology of traditional accelerated aging with temperature of 43 °C and period of 12h shows to be promising for the verification of the physiological quality of poppy seeds.

PRODUCTION OF MELON (CUCUMISMELO L.) ELDORADO 300 SEEDLINGS GROWN IN DIFFERENT SUBSTRATES AND SOWING DEPTHS

Melon (Cucumis melo L.) is one of the most consumed vegetables in the world. In recent decades, sustainable production alternatives have been sought, replacing traditional substrates with the use of substrates from organic waste. The objective of this work was to evaluate the initial development of melon seedlings in different substrates and depths of sowing, as well as to identify relationships among the characters evaluated. The experiment was conducted in a greenhouse, with a randomized block experimental design arranged in a 3x4 factorial scheme, with three substrates (grape husk, rice husk, commercial substrate) and four sowing depths (1.0, 2, 0, 3.0 and 4.0 cm), with four replicates. The evaluated characters were index of emergency speed, shoot length and root, green and dry mass of the root and shoot. The analysis of variance revealed significant interaction between substrates x depth of sowing for the character of shoot length and root length. Pearson's linear correlation revealed two significant positive associations. It is concluded that melon seedlings are affected by the substrate types and depths of sowing, the substratum based on grape bark can replace commercial substrates, the bark of charred rice does not have a positive response in the production of melon seedlings and the correlation Of Pearson showed a positive relationship between characters.

TEST OF EXUDATE pH IN RICE SEEDS

ABSTRACT The objective of this study was to evaluate the efficiency of a pH test of the exudate (with and without tegument) as an indicator of the physiological quality of rice seeds. The experimental design was completely randomized, with seven lots and four replications. The seven lots were assessed for water content and initial physiological quality by means of germination, first germination count, emergence, emergence speed index and tetrazolium tests. The pH test of the exudate was conducted with 100 seeds of each treatment, with tegument and without tegument. The seeds were individually soaked in 2.0 mL distilled water for different periods (20, 40, and 60 minutes) and three temperatures (20, 25, and 30 °C). The results were submitted to the Scott Knott test at 5% probability. The pH test of the exudate is a promising method to evaluate the physiological quality of rice seeds by detecting differences in vigor between marketable lots. This test should be conducted with rice seed without tegument, at 25 °C, with a soak time of 60 minutes.

BIOCHAR DE SERRAGEM DE EUCALIPTO COMO CONDICIONADOR DE SUBSTRATOS PARA PRODUÇÃO DE MUDAS DE ALFACE

O sucesso na produção de alface (Lactuca sativa L.) começa pela obtenção de mudas com boa qualidade sendo necessário a utilização de substratos que fornecem condições químicas e físicas favoráveis ao desenvolvimento da planta. O reaproveitamento de resíduos na produção de substratos pode ser uma proposta interessante para a produção de mudas. O trabalho objetivou avaliar a influência de biochar produzido a partir da serragem de eucalipto, no desenvolvimento de mudas de alface. O experimento foi conduzido em casa de vegetação com delineamento experimental inteiramente casualizado, com sete tratamentos e três repetições. Utilizou-se a cultivar Grandes Lagos e sete substratos sendo um comercial, Bioplant® (BPL) e seis formados a partir do substrato comercial, Bioplant® + biochar (BC 5, BC 10, BC 15, BC 25, BC 50 e BC 75% m/m). Foram avaliadas as variáveis percentagem de emergência (E), índice de velocidade de emergência (IVE), comprimento da parte aérea (CPA) e sistema radicular (CSR), massa fresca da parte aérea (MFPA) e do sistema radicular (MFSR) e massa seca da parte aérea (MSPA) e do sistema radicular (MSSR), 25 dias após a semeadura. A adição de biochar, ao substrato comercial, Bioplant®, na concentração de 5% em massa, apresentou viabilidade para ser utilizado como condicionador de substrato no desenvolvimento de mudas de alface da cultivar Grandes Lagos.

Inclusion of Babassu Decomposed Stem Substrates on the Pattern of the Vegetative Growth of Passion Fruit Seedlings

ABSTRACTThe objective of this study was to evaluate the biological rhythm of the vegetative growth and nutrient content of the yellow passion fruit seedlings produced in substrates with different levels of based on the decomposed stem and babassu (DBS): S1 – 20%, S2 – 40%, S3 – 60%, S4 – 80%, S5 – 100% DBS and S6: commercial. Were investigated the plant height (PH), stem diameter (SD), emergency speed index (ESI), germination (%G), leaves number (NL), root length (RL), root volume (RV), dry mass of the shoot (SDM), dry mass of the root system (DMRS), Dickson quality index (DQI) periodically for 60 days. The accumulated nutrient (N, P, K, Ca, Mg and B) contents were determined after this period. The data were submitted to ANOVA, significant means were compared by the Tukey test (P < .01). ANOVA results showed a significant effect (P < .01) for using DBS in 80% (S4 and S5) on RV, DQI, and DMRS in relation to the commercial one. In addition, there was greater accumulation (P < .01) of N, P, K and B in contents S4 and S5. Therefore, the use of the babassu decomposing stem as a substrate positively influences the vegetative growth rate of yellow passion fruit seedlings, especially due to its nutritional aspect, promoting a greater accumulation of nutrients, mainly boron. Mixing with the soil in the ratio 80/20, respectively, promotes the best biometric and nutritional responses, with the best quality conditions for seedling formation.

Foliar applications of phosphorus, calcium, boron and potassium and their impacts on the seed yield and physiological and nutritional qualities of soybean

Using seeds of high physiological quality is important the establishment of a crop. Practices for quality seed production include sowing in the offseason and applying foliar macro and micronutrients to supplement fertilizers applied to the soil. The aim of this research was to evaluate the soybean yield and the physiological quality and nutritional content of seeds. Foliar fertilizer (24% P, 8% Ca, 4% K and 2.5% B) was applied at 0.50, 1.0, 1.5, 2.0 and 2.5 kg ha-1 at the R3 soybean stage in a completely randomized design with six replications. The experiment was carried out at two sites. The following traits were evaluated at the R6 stage: the final stand, plant height, height of the first pod insertion, number of branches and number of pods per plant. After the soybeans were harvested, the thousand grain mass and yield were evaluated. The contents of nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, zinc, iron, copper and boron were evaluated. Furthermore, the germination, first germination count, accelerated aging, modified cold, electric conductivity and emergency speed index were measured. The data were analyzed by means of joint analysis. When the foliar fertilizer rates were significant, the polynomial regression models were adjusted. The number of pods per plant and yield increased at site 1 (Rancho Alegre d 'Oeste). Application of the foliar fertilizer only influenced the emergency speed index at site 2 (Mariluz) with regard to the physiological quality of the seeds. The P content was positively affected at both sites; the K, S, Zn and B contents were only positively affected at site 2.

Dormancy breakage and germination in Sapindus saponaria L. seeds as a function of temperature and germination substrate

The objective of this study was to evaluate different pre-germination treatments, histochemical characteristics and physiological performance of Sapindus saponaria L. seeds as a function of temperature and the germination substrate. The S. saponaria seeds were collected in the municipality of Rio Verde, GO, and analysed through the execution of 2 tests (dormancy breakage and germination tests). Test 1 consisted of 10 treatments for overcoming dormancy, whereas test 2 consisted of a 35-day evaluation of germination on several substrates (paper and sand) under the following 4 temperature conditions: 20, 25, 30°C and alternating 20-30°C (± 0.5°C). The results of the dormancy breakage and germination tests were submitted to analysis of variance (ANOVA), and the means were compared by the Tukey test. Scarifying S. saponaria seeds with concentrated sulfuric acid for 90 min provided a relatively high speed and percentage of emergence, without causing anatomical damage. Pre-germination treatments using high- (42 °C) or low-(10 °C) temperature stress caused cellular damage in the endosperm region of S. saponaria seeds. The greatest percentage of S. saponaria seeds germinated on a paper substrate at 30°C.

Emergence and Initial Development of Amaranth (Amaranthus cruentus L.) BRS Alegria at Different Depths of Seeding and Water Availability

The depth of seeding and the availability of water influence the seed germination process. Amaranth has small seeds from 1.0 to 1.5 mm and limited nutrient reserves and, after emergence, slow growth. Thus, the objective of this work was to evaluate the emergence and formation of amaranth seedlings. The experiment was carried out in a vegetation house at the Federal University of Mato Grosso - Brazil, between October and November 2018. The factor "A" refers to two seeding depths (10 and 20 mm) and the factor "B" to four of water availability (100%, 80%, 60% and 40% of retention capacity). The emergency, first count and emergency speed index were evaluated. Height, diameter, root length, number of leaves, mass of fresh and dry matter were also evaluated. The emergence of the seedlings, independently of the seeding depth, was greater in water availability of 100 and 80%. There was interaction of factors for the first count and emergency velocity index. The first emergency count was higher in water availability of 100%. At a seeding depth of 10 mm, the first count of emerging seedlings was similar in water availability of 100, 80 and 40%. While, at a depth of 20 mm, the first count was higher at water availability of 60%. The emergency speed index was higher for 100% water availability at 10 mm seeding depth, while at 20 mm depth the water availability had no effect on the emergency speed index. The water availability of 60 and 40% of the retention capacity reduces the height of the plant, the diameter of the stem, the length of the root, the number of leaves, the mass of fresh and dry matter. Increased seeding depth reduces height, number of leaves and production of fresh and dry amaranth matter.

Sewage Sludge as Fertilizer in Soybean Cultivation

The objective of the present study was to evaluate the effects of the application of treated sewage sludge on the initial development of soybean plants (Glycine max L.). Seven treatments were used: (T1) only the soil (absolute control); (T2) soil + residue at the dose of 5.0 g/dm3; (T3) soil + residue at a dose of 10.0 g/dm3; (T4) soil + residue at the dose of 15.0 g/dm3; (T5) soil + residue at the dose of 20.0 g/dm3; (T6) soil + residue at the dose of 25.0 g/dm3; and (T7) culture with PK. The variables of emergence, first count and emergence speed of seedlings, green mass, shoot length, root length, dry shoot mass and dry root mass of the plants were analyzed. The experimental design was in randomized blocks, with four replicates of 25 plants for each treatment. The use of the organic residue positively influenced the characteristics observed in relation to the control and the PK, and in the appropriate dose, it can be recommended as an input and soil conditioner. Sewage sludge presents high potential as a fertilizer for soybean cultivation.

Emergência e crescimento de Urochloa brizantha cv. Marandu em função do incrustamento da semente e profundidade de semeadura

The crop-livestock integration (ILP) consist in the adoption of several techniques, for better use of areas, formation and recovery of degraded pastures. The species of the genus Urochloa has been highlighted in the ILP and practices such as the type of seed used and the depth of sowing are fundamental for the establishment and production of the pasture. The objective of this research was to evaluate the emergence and growth of plants of Urochloa brizantha cv. Marandu, originating from seeds incrusted or not, sown in different depths and soils. The experimental design was a randomized block design with four replications. The treatments were arranged in a 2x5 factorial scheme, composed of two types of seeds (incrusted or not) seeded in five depths (0; 1; 2.5; 5; 10cm) in medium textured and clayey soils. Plants of U. brizantha from seeds incrusted and cultivated in medium textured soil presented higher emergence, but lower growth in relation to the plants coming from non-incrusted seeds. In soils of clayey texture, the use of incrusted seeds promoted a greater speed of emergency, but less growth of the plants. The sowing of U. brizantha at 1.0 and 2.5 cm depth provided a higher emergence speed, regardless of soil texture and type of seed. After forage cutting, the greatest tillering of regrowth was observed in plants from non-encrusted seeds and sown in soil up to 2.5 cm deep. At regrowth, there was no effect of treatments on forage yield.

Atividade respiratória como teste de vigor em sementes de feijão (Phaseolus vulgaris L.)

Os testes rápidos de vigor são utilizados atualmente pelas empresas produtoras de sementes para avaliar a qualidade dos lotes. A indústria sementeira com a evolução tecnológica, exige cada vez mais rapidez na separação de lotes de alto vigor. Dessa forma, o trabalho objetivou verificar a eficiência e rapidez da atividade respiratória das sementes para diferenciar o vigor de lotes de sementes de feijão. O trabalho foi realizado na Universidade Rural de Pernambuco, conduzido no Laboratório de Análise de Sementes com três lotes de feijão adquiridos em municípios do estado de Pernambuco. Foram realizados alguns testes e determinações: teor de umidade, peso de mil sementes, germinação, primeira contagem da germinação, comprimentos e massa seca da parte aérea e raiz, condutividade elétrica, emergência de plântulas, comprimentos de parte aérea, raiz e massa seca da parte aérea. O índice de velocidade de emergência indicou o lote 3 e 1 como sendo os de maiores potencias fisiológicos e o lote 2 como o de menor. As sementes de feijão do lote 2, nos testes de germinação, índice de velocidade de germinação, índice de velocidade de emergência, massa seca de parte aérea e raiz como sendo o lote de menor vigor, e o que teve a menor liberação de CO2 no teste de atividade respiratória. O teste de atividade respiratória pode ser utilizado para determinar o vigor de sementes de feijão a partir de 12 horas de embebição.