Size as a fast and non-destructive marker for predicting wheat seed physiological quality

The objective of this experiment was to determine the influence of different salt levels (zero, 15, 30, 45 and 60mM NaCl) on seed physiological quality of two wheat cultivars (BRS 177 and BRS 179). SUMMARIZE METHODOLOGY. The results allow the following conclusions: the physiological quality (germination and vigor) of wheat seeds, cultivars BRS 179 and BRS 177, decrease with the increase of the salinity. The wheat seeds cv. BRS 179 performs better than BRS 177, mainly in higher salt concentrations (³ 45mM of NaCl). The electric conductivity of wheat seeds increases in function of the increment of the saline concentrations.

Different sources and nitrogen management (N) may increase the availability, absorption, and assimilation of this nutrient by plants, favoring the N accumulation in grains. However, little is known about the influence of these factors on the physiological quality of wheat seeds (Triticum aestivum L.). In this context, the aim of this study was to evaluate the response of different sources and nitrogen fertilization, applied in cover, on the physiological quality of the wheat seeds. The experiment was conducted in a completely randomized block design in a split-design treatment plot with three cultivars of wheat (TBIO Mestre, TBIO Iguacu and Quartzo), three sources of nitrogen (urea, ammonium nitrate, and liquid urea), applied using five methods: (I: tilling; II: tilling and booting; III: tilling and flowering; IV: booting and flowering and V: tilling, booting and flowering). The nitrogen partitioning between booting and flowering stages results in higher physiological seed quality, since it increases the percentage of germination by 4% and positively influences the germination count, shoot length, and seedling dry mass. The sources of nitrogen ammonia nitrate and the urea liquid source are equated with urea in relation to the effect on the physiological quality of the seeds, being interesting alternatives to reduce the production cost. The TBIO Mestre and Quartzo cultivars showed seeds with higher physiological quality, due to the greater length of radicle and percentage of germination.

Due to the importance of triticulture for Brazilian agriculture, the study aimed to evaluate the physiological quality of wheat seeds produced in different municipalities in the north of the State of Paraná. The experiment was conducted at the Seed Laboratory of the State University of Londrina (UEL). The assay consisted of analyzing the physiological quality of wheat seeds cv. CD 116, produced in four municipalities in the state of Paraná (Rolândia, Cambé, Marilândia do Sul, and Ibiporã), in the 2011 cropping season, sampled at random in different cooperatives and seed-producing companies. The experiment was conducted in a completely randomized design and the physiological quality of the wheat seed batches was evaluated from the variables: first germination count and germination (germination test); viability (tetrazolium test); vigor (accelerated aging and cold tests); vigor, emergence speed index, and mean emergence time (seedling emergence test in the sand); shoot and seedling length, and shoot and seedling dry mass (seedling length test). The data were subjected to variance analysis and the means were compared using the Tukey test (p < 0.05). The municipality where the seeds were produced influenced the physiological quality of wheat seeds. In the present experiment, the production fields located in Rolândia and Cambé contributed to batches with greater germination and vigor. Therefore, the production environment is a factor that must be taken into consideration when planning the crop. The tetrazolium test, as well as the variables, mean emergence time, seedling length, and shoot dry mass, were not efficient in separating the batches according to physiological quality.

ABSTRACT: Defoliation may play a role in source-sink relationships and reduce the physiological quality of seeds. The main goal of this research was to investigate the effect of successive defoliations on physiological quality of wheat seeds in 'BRS Umbu' and 'BRS Tarumã' cultivars. Two experiments were carried out using a complete randomized design with four replications. Treatments included plants without defoliation (0), and those where 1, 2, and 3 consecutives defoliations were applied. Seeds from each treatment originated from four different lots. Data were analyzed with one-way analysis of variance and means compared by Tukey test at 5% statistical probability. Germination was not affected by defoliation, or the number of cuts, but an effect on vigor was reported.

Abstract: The optimal combination between sowing density and nitrogen (N) fertilization rate is a challenge for the production of high-quality seeds, considering the diversity of genotypes and environments. This study aimed to evaluate the yield and physiological quality of wheat seeds as a function of sowing density and N rate, under different edaphoclimatic conditions. The experiment was carried out in three environments (Londrina, Cascavel, and Ponta Grossa) in a randomized block design with four replications, considering a 2 × 3 × 4 factorial arrangement composed of two genotypes (BRS Anambé and WT 15-025), three sowing densities (250, 350, and 450 seeds.m−2), and four N rates (0, 40, 80, and 120 kg.ha−1). The following seed features were evaluated: yield, first germination count, final seed germination, seedling emergence, emergence speed index, seedling length, and seedling dry matter. Seed yield varied as a function of environment and genotype. BRS Anambé produced seeds with higher physiological quality. The optimal combination between sowing density and N rate that provided the more suitable economic yield, without affecting the physiological quality of wheat seeds, varied with the environment and was estimated in 250 seeds.m−2 × 0 kg.ha−1 N for Londrina and Cascavel, and 350 seeds.m−2 × 18 kg.ha−1 N for Ponta Grossa.

Wheat is one of the most important cereals grown in the world, and in Brazil, increasing national production is still a challenge. Nitrogen (N) supply can favor grain yield and the physiological quality of wheat seeds. However, the definition of adequate N rate and fertilization timing must consider genotype, cultivation environment, and initial seed vigor level. The aim of this work was to evaluate the effect of initial seed vigor and the combinations of rates and timings of N application on grain yield and seed physiological quality of wheat cultivars under different edaphoclimatic conditions. The experiment was carried out in Londrina and Ponta Grossa, state of Paraná, in a randomized block design in a 2 × 2 × 7 factorial scheme, with four replicates. Treatments consisted of two seed vigor levels (vigorous and non-vigorous seeds), two wheat cultivars (BRS Gralha-Azul and BRS Sabiá) and seven combinations of fertilization timings and N rates (kg ha-1) (control-0N; 20N at sowing and 60N at tillering; 40N at sowing; 80N at sowing; 40N at sowing and 40N at tillering; 40N at tillering; 80N at tillering). Number of emerged seedlings, vegetation index, shoot dry matter, number of fertile spikes m-2 and grain yield were evaluated. Additionally, the physiological potential of seeds produced in Londrina was evaluated by the testes of first count, germination, seedling emergence in sand and emergence speed index. The climatic conditions during the experiment, in both cultivation environments, were similar to average historical records, with some periods of water deficit. The highest grain yield was obtained with the BRS Gralha-Azul in Londrina, and with BRS Sabiá in Ponta Grossa. The use of vigorous seeds favored the stand establishment and the response of plants to N fertilization. The treatments 40N + 40N, and 40N + 0N favored the majority of evaluated variables. Both cultivars showed potential for the production of high physiological potential seeds in Londrina environment. Inadequate N supply impairs wheat grain yield and seed production.

This study evaluated the effect of the plant growth regulator trinexapac-ethyl on chemical composition and physiological quality of wheat seeds produced under fertilization for high yield potential. The experiment was performed under completely randomized design with five treatments (0; 200; 400; 600; 800 mL ha-1 of the commercial product Moddus ) and four repetitions. The plant growth regulator was applied at elongation via foliar spraying. Seeds were harvested at the end of crop cycle. Variables evaluated were 1000 seeds weight, germination and first count of germination, speed of germination index, seedling dry matter, electrical conductivity, accelerated ageing and the contents of total soluble sugars, starch, amino acids and proteins. The first count of germination increased until the higher dose. Electrical conductivity after three hours of imbibition reduced at the doses of 600 mL ha-1 and 800 mL ha-1, indicating greater seed physiological quality. Starch showed a trend of increase until the dose of 448 mL ha-1; amino acids until the dose of 243 mL ha-1 and protein until the dose of 417 mL ha-1. The content of total soluble sugars decreased with the increasing dose of the plant growth regulator. Therefore, wheat seeds produced from plants in which trinexapac-ethyl is applied present higher vigor and greater contents of starch, protein and amino acids, but lower content of total soluble sugars. Our results demonstrate that trinexapac-ethyl can be used for wheat management in seed production fields in the recommended dose (400 mL ha-1) with benefits in seed quality and composition.

Abstract: Seeds with high quality are one of the important factors to consider in the crops establishment on field. Therefore, the physical and physiological quality of wheat seeds treated with mixes of micronutrients including zinc and protective products were aimed. The wheat seeds were analyzed in a factorial scheme 5x3x4, with five storage time: 0, 60, 120, 180 and 240 days; three micronutrients: micronutrients 1 (1% Mn; 0.1% Mo; 10% Zn); micronutrients 2 (0.3% B; 0.3% Co; 3% Zn) and no micronutrients, and four protective products: untreated seeds, polymer (Colorseed He), fungicide carboxin + thiram (Vitavax® Thiram 200 SC) + insecticide thiamethoxam (Cruiser® 350 FS) and polymer + fungicide + insecticide. After treatment, the seeds were stored under uncontrolled conditions for 240 days and at intervals of 60 days, the germination, accelerated aging and moisture content were determined. Wheat seeds untreated and treated with polymer have the best physiological performance during storage, regardless micronutrients treatments. The wheat seeds treated with carboxin + thiram + thiamethoxam and polymer + carboxin + thiram + thiamethoxam can be storage up to 120 days, under uncontrolled conditions, regardless micronutrients treatments. The seed treatment does not alter the moisture content of wheat seeds.

This study aims to evaluate and compare the germination quality of wheat seeds (Triticum aestivum L.) from several genotypes in order to identify the genotype with the best germination power and vigor. The research was carried out at the Seed Technology Laboratory, Faculty of Agriculture and Business, Satya Wacana Christian University using a Group Random Design (RAK) with three replicates. Data that did not meet the assumptions of normality and homogeneity were analyzed using the non-parametric Kruskal–Wallis test and followed by the Dunn–Bonferroni test at the level of 5%. The observation parameters were grouped into germination power parameters (germination power and growth sufficiency), vigor parameters (growth speed and wet and dry weight of sprouts), and early germination growth parameters (shoot and root length and number of leaves and roots). The results showed that the genotype had a real effect on the physiological quality of wheat seeds, where the Guri 2 genotype showed the best performance with high germination power and vigor and better root growth compared to other genotypes, while the Nias genotype also showed strong vigor and good germination quality, while the Guri 4 genotype had the lowest physiological quality of seeds with low germination power and vigor. These findings confirm the importance of the role of genetic variation in determining the physiological quality of wheat seeds, so that the Guri 2 and Nias genotypes have the potential to be used as superior genetic sources in wheat breeding programs as well as as the basis for the development and production of quality seeds to support the improvement of wheat adaptation and productivity in Indonesia.

Seed treatment is a practice that helps the initial establishment of the crop without the effects caused by pests and diseases. The association of diazotrophic bacteria with grasses has been used in the supply of nitrogen to plants; however, these microorganisms produce growth-promoting substances, which promote benefits in the growth and development of the crops. Thus, the objective of this study was to evaluate the compatibility of Azospirillum brasilense associated with the fungicide difenoconazole and the insecticide thiamethoxam by observing the effects on the quality of seed emergence of three wheat cultivars (Triticum aestivum L.). Three wheat cultivars, arranged in a 4 x 2 factorial system with four replicates, were tested. The treatments were the control; difenoconazole (Spectro® at a dose of 150 mL per 100 kg of seed); thiamethoxam (Cruiser® FS 350 at a dose of 200 mL per 100 kg seed) and difenoconazole + thiamethoxam, applied on wheat cultivars TBIO Mestre, TBIO Itaipu and TBIO Sinuelo. Bacteria from the Azospirillum genus were used in the inoculation. The wheat seed retains its quality when it checks the germination, vigor and independent accelerated aging, whether or not fungicide, insecticide and A. brasilense were used. The insecticide thiamethoxam increased the length of shoots and roots and provided compatibility with A. brasilense, and fungicide inhibited the length of shoots and roots and was antagonistic to the bacterium A. brasilense.

The production of high-quality wheat seeds in soils with low soil organic matter (SOM) content requires the use of nitrogen (N) fertilization techniques, since different types of N fertilizers have different impacts on crop uptake and development. The present study aimed to evaluate the quality of wheat seeds from modern cultivars, grown in soils with low SOM content, under different ammoniacal and nitric N fertilization rates in Southern Brazil. Seeds were produced in three locations (Capão do Leão, Pelotas and Rio Grande, RS, Brazil), during two crop seasons (2021/22 and 2022/23), under N rates of 0, 40, 80, 120, and 160 kg·ha-1 of N, supplied with urea (46% N) and ammonium nitrate (AN) (27% N). Germination test, dry weight and length of aerial part and root of seedlings, accelerated aging test (AAT), emergence in seedbed, and electrical conductivity (EC) of seeds were evaluated. It was observed that seed germination presented acceptable values, with rates of viable seeds varying from 86 to 99%, except location 3, which presented values below 80% germination at the rate of 160 kg·ha-1 of N. A reduction in seed vigor was observed with the use of AN. Increasing N rates reduced germination in AAT and increased seed EC. EC has a negative correlation with all parameters indicating good physiological seed quality. It was concluded that excessive rates of N negatively impact the physiological potential of wheat seeds grown in soils with low SOM contents.

Plant lodging in wheat has been controlled through growth retardants. However, there is lack of information on the effect of these products on the physiological quality of seeds. The objective of this study was to evaluate the physiological quality of wheat seeds obtained under different rates and application times of three growth retardants. The trial was carried out in Viçosa-MG, from May to September 2005, in a factorial and hierarchical scheme, in randomized block design with four replications and a control treatment. The treatments consisted of 500, 1000 and 1500g ha-1 of chlormequat; 40, 80 and 120g ha-1 of paclobutrazol and 62.5, 125 and 187.5g ha-1 of trinexapac-ethyl applied at the 6 or 8 growth stage based on the scale of Feeks and Large, and a control treatment without growth retardant application. Leaf application of growth retardants as chlormequat, paclobutrazol and trinexapac-ethyl did not affect the germination and vigor of wheat seeds.

The hydration pattern associated with the physiological quality of seeds can be an early indicator for the evaluation of seed quality. The present study aimed to evaluate the hydration pattern of seeds subjected, or not, to water restriction, and to relate these patterns to their physiological quality. The physiological quality of seeds from five maize strains (L1, L2, L3, L4, and L5) and four hybrids (HT1, HT2, HS1, and HS2) was initially determined using seed germination and vigor tests (accelerated ageing and electric conductivity). A completely randomized experimental design was used with four repeats for the physiological analyses and a regression analysis was performed in order to assess the behavior of the seeds over time. The hydration curve was determined by imbibing the seeds in distilled water (0.0 control) and in a -0.9-MPa osmotic solution of polyethylene glycol 6000. Water uptake by the seeds was found to follow a triphasic pattern in the absence of water stress (0.0 MPa); however, when exposed to a -0.9- MPa osmotic potential, an extended phase II was observed. Diversity was observed between the strains in terms of the hydration pattern of the seeds, which can influence the physiological quality of the hybrid seeds. Regarding the hybrids, a positive relationship was observed between the shortest time to root protrusion and the quality of the seeds, both with or without water restriction, which allows us to conclude that hydration pattern can be used as a parameter for the early evaluation of physiological quality in hybrid maize seeds.

Barley (Hordeum vulgare L.) is considered one of the most important cereals, such as maize, rice and wheat, due to its multiplicity of usage, as much for human consumption as for feed. The Nitrogen is one of the main nutrients that influences the quality and productivity of barley seeds because it participates in numerous metabolic routes. It is a limiting factor of the production, the lack or the excess can bring consequence to the culture. In this manner, the present study aims to evaluate the influence of different nitrogen doses on the physiologic quality and biochemical characters of brewing barley seeds produced in two growing environments. The experiment was conducted in the 2017 crop season, in a randomized block design, organized in a factorial scheme, being 2 cultivation environment × 2 brewing barley cultivars × 4 nitrogen doses, disposed in four replicates. The physiological quality of the seeds was evaluated by germination, first counting of germination, accelerated aging, field emergence, shoot and root length, dry mass of shoot and root of seedlings, electrical conductivity (3, 6 and 24 hours) and isoenzymes. The growing environment promotes differences in the barley seeds physiologic quality. The nitrogen fertilizing, at dose of 120 kg ha-1, results in superiority in the physiologic quality of seeds. The cultivar BRS Cauê in both environments presented higher vigor. The nitrogen fertilizing alters the isoenzymatic expression of barley seedlings, creating variation in the bands intensity, at different nitrogen doses.

The aim of this study was to evaluate physiological quality in the seeds of four cowpea cultivars during nine months of storage. The cowpea cultivars used were BRS Mazagao, UFRR Grao Verde, Pretinho Precoce 1 and BRS Guariba, produced intercropped with cassava in the experimental area of the Centre for Agrarian Science of the Federal University of Roraima, in Boa Vista. After harvest, the seeds were dried, hand cleaned, placed in PET bottles and stored for nine months at a temperature of 23 oC and a relative humidity of 60% at the Seed Analysis Laboratory of Embrapa Roraima. Data analysis was carried out in a completely randomised design, in a 4 x 4 factorial scheme with eight replications. The physiological quality of the seeds was evaluated at the start of storage, and after 3, 6 and 9 months, for germination, first germination count, 1000-seed weight, moisture, electrical conductivity, speed of emergence, seedling field emergence and water gain. Physiological quality in the seeds of BRS Guariba is influenced by the storage period. Irrespective of storage period, seeds of the Mazagao cultivar show superior physiological quality in relation to the other cultivars. Seeds of the BRS Guariba and Grao Verde cultivars show a reduction in physiological quality after three months of storage.