Seedling Emergence In Field Research Articles

Combined vigour tests to estimate relative seedling emergence in the field and germination after storage in sweet corn seed lots

This study was carried out to test whether the radicle emergence (RE), cold (CT) and accelerated ageing (AAT) tests and their combinations of CT+RE and AAT+RE can be used to rank sweet corn seed lots according to field seedling emergence and germination after storage. Seed samples for eight hybrid seed lots were stored hermetically over 12 months at 20°C with 9.9-10.2% seed moisture. RE was counted between 32 and 72 hours, AAT was carried out at 41 ± 1°C and 100% RH for 72 hours, and CT at 5°C over two days. RE count was performed after AAT (AAT+RE) and CT (CT+RE). Seedling emergence was tested in two field sowings, in April and May 2022. The vigour test results were correlated with both seedling emergence percentages in the field and germination after storage. Both normal germination after CT (r = 0.73−0.94, P < 0.05−0.001) and AAT+RE72h (r = 0.71−0.84, P < 0.05−0.01) were significantly related to both parameters. The RE test was significantly related to seedling emergence, but not to any post-storage data. The normal seed germination percentage was found to be significant in only one case (sowing 2). Seed vigour in sweet corn seeds and its importance in relation to seedling emergence and seed storage are discussed.

Rupture Test: A New Method for Evaluating Maize (Zea mays) Seed Vigour.

To explore the application of seed germination biomechanical event(s) in seed vigour tests, a new procedure for the evaluation of maize seed vigour tests based on pericarp-testa rupture (PR) and coleorhiza rupture (CR) during seed germination was developed. Twenty-four lots of hybrid maize were used to determine the feasibility of the rupture test (RT) as a seed vigour test in Zea mays. The results showed that the physiological quality pattern of 24 maize seed lots assessed through RT was similar to that obtained through analysis with other seed test methods. Correlation and regression analyses revealed that the percentage of CR and percentage of PR + CR at "15 ± 0.5 °C for 120 h ± 1 h" and "20 ± 0.5 °C for 72 h ± 15 min" exhibited positive correlations with the field seedling emergence data (p < 0.01). Hence, the proposed method (the rupture test) is cogent and effective, thus providing an important reference for more crops to select for seed germination event(s) and establishing corresponding new methods for seed vigour tests in the future.

Assessment of physiological quality of commercial maize-seed lots for quality a ssurance in the Nigerian seed industry

Maize productivity in Nigeria fluctuates over the years partly due to the use of seed lots with poor seed quality. The aim of this study was to assess problems associated with physiological quality for commercial maize seed lots in the Nigerian seed industry. Fifty samples of commercial maize seed-lots of the same variety, 'Sammaz 15', were collected from 50 seed companies across the country. Moisture content, standard germination, bulk conductivity, accelerated ageing, seedling vigour and field seedling emergence tests were performed on the seeds. The assessments were conducted in two consecutive years. Across the years, mean seed moisture content was 10.6%, germination was 93.7%, bulk conductivity was 8.10 μS cm-1 g-1 and 1000-seed weight was 245.2 g. Mean values for length of mesocotyl, coleoptile, primary leaf, shoot and root were 30.7, 35.6, 65.1, 97.7 and 210.5 mm, respectively. Mean values for field emergence and accelerated ageing were 88.5 and 68.8%, respectively. There were significant correlations between germination percentage, bulk conductivity, accelerated ageing germination percentage and ageing index and field emergence. Correlations with moisture content were poor. The ageing test showed that storability was low. Breeders should select for seed with good storability to ensure quality maize seed production.

Radicle emergence test for soybean vigour testing

This study was carried out to determine the use of single counts of radicle emergence to test seed vigour and estimate seedling field emergence of soybean (Glycine max) seed lots. Results of radicle emergence (RE) (production of 2 mm radicle) at 20°C for 48 hours and 25°C for 24 hours, mean germination time (MGT), tetrazo lium vigour test (TZ) and field emergence (FE) were compared using nine soybean seed lots with standard germination above 80%. The single counts of RE performed at 20 and 25°C were significantly correlated with the MGT at the same temperature (R2 = 0.82 and 0.89, respectively) and with the TZ vigour (R2 = 0.96 and 0.93, respectively). The RE counts at both temperatures also estimated the field emergence of the seed lots (R2 = 0.74 at 20°C and 0.68 at 25°C). The TZ vigour results had a significant correlation with the seedling field emergence (R2 = 0.70). Results indicate that a single count of radicle emergence after 48 hours at 20°C or 24 hours at 25°C is an efficient option for soybean seed vigour assessment.

Evaluation and improvement of the health status of farmer-saved okra (&lt;i&gt;Abelmoschus esculentus&lt;/i&gt; (L.) Moench) seeds in the Ashanti Region of Ghana

Farmer-saved seeds are major plant pathogen carriers, which serve as the primary source of inocula of many diseases leading to massive crop losses. In view of this, laboratory experiments to evaluate seed quality and prevalence of seed-borne fungi of farmer-saved okra seeds in 10 major okra growing communities in the Ashanti region were conducted. Two local okra varieties (Asontem and Asante Aba) were collected from farmers for the laboratory studies. Although the collected seeds were observed to be of high purity, their moisture contents were high. The germination percentage, percentage of normal roots, field emergence and establishment of seedlings derived from okra seeds were also low. The study moreover showed high total seed-borne fungi infection. Health testing of the okra seeds revealed the presence of eight seed-borne fungi namely Fusarium sp., Colletotrichum sp., Aspergillus flavus, A. niger, Rhizopus sp., Mucor sp., Penicillium sp. and Curvularia sp. Seeds of Asante Aba variety showed good quality characteristics over seeds of Asontem. Seeds of the two varieties placed in airtight plastic containers stored better than seeds placed in insecticide-treated mosquito nets. Treatment of okra seeds with Dresscare and Senna siamea wood ash resulted in a lower incidence of seed-borne fungi and better seed quality characteristics. Treating okra seeds with Dresscare and Senna siamea wood ash and storing in airtight plastic containers is therefore recommended.

Effect of Seed Source on Seed Vigour and Field Performance of the Sorghum [Sorghum bicolor. (L.) Moench] Cultivar Taba

A set of laboratory tests and field experiments were conductedfor two consecutive seasons (2009/10 and 2010/11) to investigate theeffect of seed source on seed quality attributes of the sorghum cultivarTabat. Simple correlation coefficients were calculated to determine thedegree of association between the different vigour tests and seedlingemergence under field conditions. Seeds were obtained from fourlocations: two rainfed (Damazin and Habeela) and two irrigated (KhashmEl Girba and El Gezira). Data were collected on initial seed moisturecontent, 1000-seed weight, germination percentage, rate of germination,seedling shoot length, seedling root length, seedling shoot to root lengthratio, seedling fresh weight, seedling dry weight, plant height, number ofleaves per plant, leaf area per plant and plant fresh and dry weight. Theresults indicated that, under laboratory conditions, seed source hadsignificant effect on seedling root length and fresh weight in the firstseason, on germination percentage and rate of germination in the secondseason and on seed moisture content and 1000 seed weight in bothseasons. Significant differences were found in seedling shoot length andplant height under field conditions. Seeds from Habeela and Damazinperformed well with regard to germination percentage, rate ofgermination and field seedling emergence. Also, seeds from the rainfedareas produced taller plants than those from irrigated areas (Khashm ElGirba and El Gezira). The results also showed that field seedlingemergence was positively correlated with the estimate, under laboratory

Seed Vigour and Morphological and Physiological Characteristics of Epimedium brevicornu Maxim: In Different Stages of Seed Development.

Epimedium brevicornu Maxim is a traditional Chinese medicinal plant with important value for curing several diseases, including liver cancer. Seed germination, field seedling emergence, and morphological and physiological traits were measured in developing seeds of E. brevicornu, which were collected at 7, 14, 21, 28, and 35 days after flowering. The results showed that with the fruit pericarp changing from lime green to dark red, the seed volume increased. Furthermore, the dry mass of seeds gradually increased from 0.011 g at 7 d to 0.275 g at 35 d, which was a significantly positive correlation with seed vigour (r = 0.980). The soluble protein content initially increased and then decreased to 11.09 mg/g and presented a maximum at 28 d; however, the soluble sugar content gradually declined to a minimum of 30.45 mg/g at 35 d, which was also significantly negatively correlated with seed vigour (r = −0.915). Furthermore, the unsaturated fatty acids (oleic acid and linoleic acid) increase with seed development. Abscisic acid (ABA) reached a maximum value of 18.45 ng/g at 28 d, and gibberellin (GA3), 3-Indoleacetic acid (IAA) and zeatin-riboside (ZR) initially increased and then decreased. These results suggest that the vigour of E. brevicornu seeds is closely associated with their stage of development, with the highest vigour observed at 28~35 d after flowering.

Climate effect on Avena fatua field emergence dynamics: A 38‐year experiment in the semiarid Pampean region of Argentina

Climate events modulate weed population dynamics mainly by influencing field seedling emergence patterns. Field experiments aiming to study the influence of climate on the early-stage establishment of weeds are of utmost importance from a practical and strategic decision-making management point of view. The objective of this study was to analyse the effect of climate variations on the field emergence dynamics of Avena fatua in the southwest area of the semiarid Pampean region of Argentina. Field emergence patterns of A. fatua were monitored from 1977 to 2015. Seedling counts were destructively sampled at weekly intervals. Three quadrats (1 m2 each) were randomly distributed on a 5 ha experimental field with a high natural population density of A. fatua in the absence of a crop. Results show that the emergence strategy of this species is highly plastic with a striking variation in response to year-to-year climate signals. Avena fatua field emergence strategies were classified as staggered, early, medium and late based on both chronological and hydrothermal-time parameters. In the short-term, precipitation regimes during both the after-ripening and emergence phases largely explained the resulting emergence strategy. In the long-term, the combined effect of a reduction in both the precipitation frequency and the mean minimum temperature correlated with an increase in the staggered emergence pattern. Results also point out the adaptability of A. fatua in the area under study, further suggesting a bet-hedging fitness strategy that could diminish the risk of population decline under changing climate scenarios. From an agronomic perspective, the occurrence of staggered emergence patterns with an extended emergence window would complicate the definition of the optimal time for weed control. Thus, tailoring decisions based on the Southern Oscillation Index (SOI) episodes (neutral, negative or positive) forecast plus the implementation of weed emergence models could lead to more accurate and sustainable weed management decisions.

ELECTRICAL CONDUCTIVITY AND ETHANOL RELEASE TO ASSESS RED RICE SEED VIGOR1

ABSTRACT To evaluate seed vigor, electrical conductivity and ethanol tests are fast and efficient methodologies. They have the potential to be used in several species, such as red rice. However, there are no protocols or information about their efficiency. Thus, the objective was to evaluate the efficiency, and define parameters of execution for electrical conductivity and ethanol tests, to evaluate the vigor of red rice seeds. The study was conducted using four lots of ‘BRS 901’ red rice, which was subjected to a germination test, as well as first count, accelerated aging, and field seedling emergence tests. The electrical conductivity test was performed with 25, 50, and 100 seeds soaked in 50 mL and 75 mL of water, at 25 °C and 30 °C, for 3, 6, 20, and 24 hours, respectively. The ethanol test was performed with 50 and 100 seeds soaked in a volume of water equivalent to 1.0, 1.5, 2.0, 2.5, and 3.0× the mass of the seed sample. To assess the vigor of red rice seeds, the electrical conductivity test is an efficient method when conducted with 50 seeds soaked in 50 mL of water at 25 °C for 20 hours. Meanwhile, the ethanol test is most effective when performed with 50 seeds, in a volume of water that is 2.5× the mass of the sample, at 40 °C for 24 hours.

Seed biostimulant Bacillus sp. MGW9 improves the salt tolerance of maize during seed germination

Crop performance is seriously affected by high salt concentrations in soils. To develop improved seed pre-sowing treatment technologies, it is crucial to improve the salt tolerance of seed germination. Here, we isolated and identified the strain Bacillus sp. MGW9 and developed the seed biostimulant MGW9. The effects of seed biopriming with the seed biostimulant MGW9 in maize (Zea mays L.) under saline conditions were studied. The results show that the strain Bacillus sp. MGW9 has characteristics such as salt tolerance, nitrogen fixation, phosphorus dissolution, and indole-3-acetic acid production. Seed biopriming with the seed biostimulant MGW9 enhanced the performance of maize during seed germination under salinity stress, improving the germination energy, germination percentage, shoot/seedling length, primary root length, shoot/seedling fresh weight, shoot/seedling dry weight, root fresh weight and root dry weight. Seed biostimulant MGW9 biopriming also alleviated the salinity damage to maize by improving the relative water content, chlorophyll content, proline content, soluble sugar content, root activity, and activities of superoxide dismutase, catalase, peroxidase and ascorbate peroxidase, while decreasing the malondialdehyde content. In particular, the field seedling emergence of maize seeds in saline-alkali soil can be improved by biopriming with the seed biostimulant MGW9. Therefore, maize seed biopriming with the seed biostimulant MGW9 could be an effective approach to overcoming the inhibitory effects of salinity stress and promoting seed germination and seedling growth.

GhCIPK6a increases salt tolerance in transgenic upland cotton by involving in ROS scavenging and MAPK signaling pathways

BackgroundSalt stress is one of the most damaging abiotic stresses in production of Upland cotton (Gossypium hirsutum). Upland cotton is defined as a medium salt-tolerant crop. Salinity hinders root development, shoots growth, and reduces the fiber quality.ResultsOur previous study verified a GhCIPK6a gene response to salt stress in G. hirsutum. The homologs of GhCIPK6a were analyzed in A2 (G. arboreum), D5 (G. raimondii), and AD1 (G. hirsutum) genomes. GhCIPK6a localized to the vacuole and cell membrane. The GhCBL1-GhCIPK6a and GhCBL8-GhCIPK6a complexes localized to the nucleus and cytomembrane. Overexpression of GhCIPK6a enhanced expression levels of co-expressed genes induced by salt stress, which scavenged ROS and involved in MAPK signaling pathways verified by RNA-seq analysis. Water absorption capacity and cell membrane stability of seeds from GhCIPK6a overexpressed lines was higher than that of wild-type seeds during imbibed germination stage. The seed germination rates and seedling field emergence percentages of GhCIPK6a overexpressed lines were higher than that of control line under salt stress. Moreover, overexpressing of GhCIPK6a in cotton increased lint percentage, and fiber length uniformity under salt stress.ConclusionsWe verified the function of GhCIPK6a by transformation and RNA-seq analysis. GhCIPK6a overexpressed lines exhibited higher tolerance to abiotic stresses, which functioned by involving in ROS scavenging and MAPK pathways. Therefore, GhCIPK6a has the potential for cotton breeding to improve stress-tolerance.

A Comparative Analysis of the Hybrid Maize (Zea mays L.) Seed Quality in China from 2013 to 2018

In this study, a comparative analysis of seed quality indicators of 1196 hybrid maize seed samples from the main maize-producing areas in China from 2013 to 2018 was carried out. The results showed that the maize seed quality in China had changed obviously in the past six years, and was mainly as follows: The percentage of samples with coated seed in 2015–2018 was higher than 62.8% in 2013 and all exceeded 97%; the sample rate of packaging according to seed number was from 24.5% in 2013 to 58.6% in 2018, and the percentage of samples which met the prescribed quality standards was from 89.2% in 2013 to 98.4% in 2018. Principal component analysis indicated that standard germination energy (SGE), standard germination percentage (SGP), cold test germination percentage (CTGP), accelerated aging test germination percentage (AATGP), and mean field seedling emergence (FSE) were the primary predictors of seed germination and seedling emergence. Meanwhile, combining other statistical methods, regression models of SGE, SGP, CTGP, and AATGP were established to predict the field seedling emergence. Furthermore, seed bulk density and total starch content were correlated with seed vigor, which needs to be further studied. This study offered a theoretical basis and data support to better understand the changes of maize quality in China over the past six years, and provided an important reference to further improve the maize seed quality in the future.

Fossorial birds help shape the plant community of a Peruvian desert

The Lomas ecosystems are fog-dependent oases within the hyper arid band of the Peruvian coast. Biological soil crusts (BSC) formed in the Lomas interact with the fauna and flora, but relationships among these groups have not been investigated. Here we asked if natural bioperturbations made by fossorial birds that disrupt BSC cover are increasing plant diversity in the Lomas at the National Reserve of Lachay in Peru. We analyzed active and inactive avian bioperturbations and measured the soil seed bank and the field emergence of seedlings. The plant community observed in the soil seed bank showed lower abundance of seedlings in active bioperturbations than undisturbed BSC or inactive bioperturbations. However, the emergence of seedlings in the field presented a different pattern, where both active and inactive bioperturbations were richer and more abundant in seedlings than the soil with undisturbed BSC. Our results show that bioperturbations by fossorial birds have a positive effect on seed germination and supports a richer vascular plant community in a unique ecosystem of the Peruvian desert. Here we demonstrate the importance of spatial and temporal heterogeneity for ecosystem structure and functioning.

Treatment of soybean seeds with molybdenum and inoculant: nitrate reductase activity and agronomic performance

The aim of this study was to analyze the effects of molybdenum and inoculant application via seed treatment in soybean, and their role in the nitrate reductase enzyme activity, agronomic traits and physiological quality of the produced seeds. The experiment was conducted at the Federal University of Pelotas (UFPel), Rio Grande do Sul state, Brazil. The treatments were shaped by five doses of molybdenum (zero; 16; 32; 48; 64 g.100kg-1 of seeds) combined with the presence and absence of liquid inoculant (Bradyrhizobium japonicum), at a dose of 200 mL per 100 kg of seeds. The evaluations of nitrate reductase activity, agronomic traits and physiological seed quality were performed in the present work. The measured agronomic traits were: plant height, number of pods per plant, number of seed per plant and thousand-seed weight. Standard germination test was executed to evaluate the produced seed viability. First germination counting, accelerated aging test, cold test, plantlet shoot and root length, plantlet shoot and root dry mass, and field seedling emergence were utilized to measure the seed vigour. Molybdenum, both in presence and absence of inoculant, positively influenced the enzymatic activity, for both vegetative and reproductive stages. The addition of inoculant and molybdenum provided increase in the vigour of the produced seeds. The enzyme activity was positively correlated with the agronomic traits and vigour tests. The addition of inoculant and molybdenum in the seed treatment provides a better expression of nitrate reductase activity and vigour of the produced seeds.

Sowing depth of annual ryegrass seed on different substrates as a vigor test

Abstract: Annual ryegrass seeds having low physiological quality can lead to the formation of pastures with undesirable plant stands for soil cover and forage utilization pastures. Thus, the objective of this study was proposing a vigor test to classify annual ryegrass seeds. For that, different sowing depths (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 cm) over three substrates (sand, coconut fiber, and carbonized rice husk) were tested to differentiate the physiological quality of four seed lots of annual ryegrass cv. BRS Ponteio having similarities in germination and moisture. The seed lots were classified according to vigor through the field seedling emergence (FSE), 1,000-seeds weight, saturated salt accelerated aging, and germination first count. The 2.5 cm of sand sowing depth and 3.0 cm of coconut fiber sowing depth provided separation of seed lots in similar groups of those reported to FSE test through the seedling emergence and speed of seedling emergence tests.

Vigor-S, a new system for evaluating the physiological potential of maize seeds

The refinement of vigor tests and the possibility of utilizing computer resources for the effective evaluation of the seed physiological potential have attracted considerable interest from research and seed technologists. The aim of this study was to evaluate the physiological potential of maize seeds using the newly-created Automated Analysis of Seed Vigor System (Vigor-S) compared with other recommended seed vigor tests; two maize hybrids were used, each represented by seven seed lots. Germination and vigor (cold test, saturated salt accelerated aging, and field seedling emergence) evaluations were conducted. For the evaluation of seed vigor with the use of seedling image analysis resources, two systems were compared: the Seed Vigor Imaging System (SVIS®), developed by Ohio State University, USA and the Vigor-S, resulting from collaboration between USP/ESALQ and EMBRAPA (Embrapa Instrumentation). Using these two systems, three day old seedlings were scanned and the images were analyzed. Similar results for the vigor index, uniformity of development, and seedling length were obtained. The computerized image analysis of seedlings using Vigor-S has advantages with respect to accuracy, speed, and the possibility of automatic application to a worksheet. It is a consistent alternative for the evaluation of maize seed vigor, and produces information compatible with that obtained by the accelerated aging test and SVIS®.

Single seed precise sowing of maize using computer simulation.

In order to test the feasibility of computer simulation in field maize planting, the selection of the method of single seed precise sowing in maize is studied based on the quadratic function model Y = A×(D-Dm)2+Ym, which depicts the relationship between maize yield and planting density. And the advantages and disadvantages of the two planting methods under the condition of single seed sowing are also compared: Method 1 is optimum density planting, while Method 2 is the ideal seedling emergence number planting. It is found that the yield reduction rate and yield fluctuation of Method 2 are all lower than those of Method 1. The yield of Method 2 increased by at least 0.043 t/hm2, and showed more advantages over Method 1 with higher yield level. Further study made on the influence of seedling emergence rate on the yield of maize finds that the yields of the two methods are both highly positively correlated with the seedling emergence rate and the standard deviations of their yields are both highly negatively correlated with the seedling emergence rate. For the study of the break-up problem of sparse caused by the method of single seed precise sowing, the definition of seedling missing spots is put forward. The study found that the relationship between number of hundred-dot spot and field seedling emergence rate is as the parabola function y = -189.32x2 + 309.55x - 118.95 and the relationship between number of spot missing seedling and field seedling emergence rate is as the negative exponent function y = 395.69e-6.144x. The results may help to guide the maize seeds production and single seed precise sowing to some extent.

Seedling emergence of 144 subalpine meadow plants: effects of phylogeny, life cycle type and seed mass

AbstractTiming of seedling emergence is a critical aspect of a plant's life cycle, and it may influence the expression of other plant life history traits. However, most studies have been conducted at the population level, and thus little is known about timing of seedling emergence at the community level. In the field, we determined the peak emergence season for seedlings of 144 species collected from a subalpine meadow on the eastern Tibet Plateau in China. The proportion of species with seedlings emerging in autumn, spring and summer, seedling field emergence percentage (FE) and mean emergence time (MET) were analysed in relation to seed mass, life cycle type (annual/biennial and perennial) and phylogeny. The results showed that (1) the proportion of species with seedlings emerging in autumn (33%), spring (44%) and summer (23%) differed significantly; (2) overall, species with seedlings emerging in autumn had higher FE than those emerging during spring/summer; (3) there was a positive relationship between log-seed mass and log-MET, but log-seed mass had no significant effect on log-FE; (4) life cycle type did not affect seedling emergence; and (5) phylogeny significantly explained peak emergence season. These results suggest that seed mass and phylogenetic position are the main determinants of seedling emergence season. However, seedling peak emergence season affected FE, growing season length and resource utilization, and thus may be related to the importance of a species in the community.

Qualidade de sementes de alface avaliada pelo teste de envelhecimento acelerado

Accelerated aging as a vigor test has been one of the most used, and its application suits many crops. The aim of this research was to analyze the applicability of the accelerated aging test in the vigor of lettuce seeds (Lactuca sativa) by its correlation with other tests for the expeditious evaluation of the physiological quality of the horticultural seeds. Six lots of lettuce seeds were used. The first count of germination, standard germination, electrical conductivity, accelerated aging, controlled deterioration, and seedling's field emergence was performed. The design was completely randomized, with four replications. The use of the accelerated aging test at 41°C per 24 h period using saturated NaCl solution is indicated for the evaluation of lettuce seed vigor.

Vigor tests in assessing the quality of signal grass seeds

The correct assessment of the physiological quality of seed lots is necessary for the quality control program of companies. For such purpose, tests that detect differences in the physiological potential of seed lots and that meet the minimum market requirements. Thus, the study was conducted towards assessing the efficiency of laboratory tests in differentiating the quality of Brachiaria brizantha cv. Xaraés seed lots. Seeds from nine lots were assessed regarding water content, germination, first germination count, electrical conductivity and seedling emergence in sand in the laboratory (normal seedlings, first count and germination rate index), and the results were compared with those from the seedling emergence test conducted in the field. The experimental design used was completely randomized, with four replicates, and the Pearson correlation coefficient between the values from the germination, vigor and field seedling emergence tests was determined. The germination and seedling emergence in sand tests and the seedling emergence rate index efficiently assess the physiological quality of Brachiaria brizantha cv. Xaraés seed lots, providing data similar to those from seedling emergence in the field.