Brazil
Brazilian Archives of Biology and Technology
Table of contents previous current next
Table of contents
Article - Agriculture, Agribusiness and Biotechnology • Braz. arch. biol. technol. 68 • 2025 • https://doi.org/10.1590/1678-4324-2025241009 linkcopy

Open-access Seed Storage and Germination of Three Grass Species: Effect of Spikelet Weight and Dormancy

AuthorshipSCIMAGO INSTITUTIONS RANKINGS

Abstract

Dormancy is a plant strategy that distributes germination over time. Domestication changed this in many cultivated species. However, many still retain this characteristic because it has not been completely removed or domesticated, especially in apomictic plants. Urochloa is a tropical grassland; for cultivated materials, apomixis is the rule, except for U. ruziziensis. This work evaluated spikelet dormancy release in three Urochloa species in two storage conditions. Different lots were cleaned and split into two portions: light (LS) and heavy spikelets (HS) that were split again into two storage conditions at 4.5% RH (relative humidity) or at 50% RH. Spikelets were analysed at three-month intervals during the first year and then until 44 months for U. brizantha and U. humidicola and 40 months for U. ruziziensis through germination and the tetrazolium test. The results showed that storage at low RH maintained the germination and vigour of “Marandu”, “Basilisk”, “Llanero” and “Kennedy’ but not for “Tully”. Dormancy released was achieved after 3 months of storage for all cultivars of U. brizantha, “Tully” and “Kennedy’, “Llanero” maintained a high amount of dormancy until 12 months. U. brizantha cultivars and “Kennedy” exhibited a lower dormancy than U. humidicola “Llanero. The heaviest spikelets conserve better at 4.5 and 50% RH conditions studied.

Keywords:
storability; post-maturation; Urochloa humidicola; Urochloa brizantha; Urochloa ruziziensis.

HIGHLIGHTS

Urochloa species are wild and are used as forage crops, with non-uniform spikelet maturation.

Dormancy is common on those spikelets, even in those that reach maturation.

Storage of those spikelet is not properly understood under different conditions.

Heavy spikelets stored better in dry conditions under controlled temperature (20 C).

INTRODUCTION

Seed dormancy is a series of mechanisms that prevent immediate seed germination, even under appropriate conditions. It is an evolutionary adaptation that allows seeds to germinate only when signs indicate that conditions are favourable for the growth and establishment of the plant, a mechanism influenced by several factors, such as permeability of the seed coat, hormonal balance, ROS - reactive oxygen species content, among others [1,2].

In seeds of several economically important crops, dormancy has been removed [3], seeking rapid and uniform germination. However, this is not the case for grasses (Poaceae), particularly tropical and subtropical species, where the fruit, a caryopsis, is enclosed in glumes and glumeles forming the propagule, known as spikelet, which dormancy characteristics are still often very similar to those of wild forms [4,5] since species of the genus Urochloa are non-domesticated species and as such flowering is distributed for a long season.

Dormancy is divided into five classes: morphological, morphophysiological, physiological, physical and combined. Physiological dormancy can be deep to intermediate, and the most common type is non-deep, which is the type present in seeds from several families [1,2]. An important characteristic of seeds with non-deep physiological dormancy is that dormancy release may occur during dry storage [6].

At the beginning of storage, oxidative events may trigger dormancy release [7,8], a beneficial mechanism that can enhance seed germination. Survival in the dry state is dependent on efficient cellular protection mechanisms to ensure survival in conditions of low water availability. Cells reduce their metabolic activity and enter a quiescent state, leading to an accumulation of soluble non-reducing sugars, which transforms the cytoplasm into a glassy state, reducing molecular mobility [7].In Urochloa humidicola “Llanero”, it was found that the release of dormancy during storage is mainly caused by the accumulation of reactive oxygen species (ROS) in spikelets, even in ultra-dry storage conditions (4.5% RH - relative humidity). Furthermore, it was found that this process can be accelerated by storing spikelets with a water content of 0.1 g H2O g-1 dry matter at 20°C [8]. However, suppose the spikelets are stored for a long period under non-controlled conditions, they may lose their viability due to the accumulation of ROS and a decrease in the antioxidant potential of the embryo's cells [11,12], as the seeds age, more ROS are produced. The metabolism is less able to react to it. Oxygen plays a crucial role in releasing dormancy, and it may trigger both germination and dormancy, depending on the species [9-12].

Seed germination of many species will occur within a limit called the "oxidative window" [13-16]; that is, when levels are below the oxidative window, the amount of ROS is too low to allow signalling for germination when ROS levels are above this window, seeds suffer oxidative damage and start ageing, resulting in deterioration and decreased germination. ROS-scavenging enzymes play a crucial role in modulating the ROS content, allowing the signal to initiate the germination process during the initial stages of imbibition [17].

Post-ripening is a natural process that occurs during dry storage at room temperature, where seeds undergo changes resulting in the loss of dormancy and the acquisition of germination capacity. This process involves the reduced expression of specific genes that promote dormancy in stored seeds, ultimately leading to dormancy release. However, it is crucial to consider that after-ripening requirements vary among species, and prolonged storage may induce secondary dormancy in some species or even lead to seed ageing and death [6,18-22].

The conditions required for after-ripening maturation may vary depending on the species, as well as the duration of dormancy release. Wild species tend to disperse their flowering period to guarantee the seed distribution and germination in a wider range of situations [23].

In Lolium rigidum Gaud. (annual ryegrass) the dormancy release was investigated concerning the water content of the spikelets and temperature; the humidity varied between 6 and 18% of the dry mass, maintained at constant temperatures between 9 and 50°C for up to 23 weeks, and it was found that the rate of dormancy release was greater at high temperatures and humidity [24].

In wild species, there are differences in the flowering that is spread in time, and consequently in seed filling and at the maturing stages of the seeds [23], and as the environment cool and becomes dryer all the seeds are shattered in the soil, and are harvested, in most cultivars, from it. U. humidicola “Tully” exhibits a more synchronous flowering [27] directly from the panicles; however, the spikelets are not fully mature. Many of them have reached the maximum dry matter content but still exhibit dormancy, which may interfere with the rest of the spikelet's life.

During storage, the seed loses dormancy but also ages, losing quality; the critical factors during storage are seed type, moisture content, initial viability, storage temperature and time, RH and protection against fungi and insects of storage, in addition to the history of the seed before storage, that is its initial quality [25].

Therefore, the objective of the work was to evaluate in seeds with complete and non-complete formation the break of spikelet dormancy and aging throughout storage under different conditions.

MATERIAL AND METHODS

Spikelet selection and storage

The experiment was conducted using samples of three lots of Urochloa humidicola “Tully” and “Llanero”; five lots of U. brizantha, three of “Marandu” and two of “Basilisk”; and two spikelet lots of U. ruziziensis cv. Kennedy, weighing 1to 3 kg.

The spikelets were cleaned, and the lots were split into two portions: light spikelets (half filled, LS) and heavy spikelets (HS); this separation was carried out by an airflow in a seed blower South Dakota (DeLeo, Porto Alegre/RS).

Each portion of light and heavy spikelets was divided and placed in two storage environments. The portions were placed in thin paper bags that were equilibrated on white silica gel (with orange silica used as an indicator), which provides 4.5% RH, or over a lithium chloride solution (36.4 g of LiCl in 100 mL of H2O), which provides 50% RH [26]. The spikelets were placed in two plastic boxes with rubber seals [28.5 x 10.0 x 21.5 cm) and maintained at 20 ± 3°C with silica gel or lithium chloride during storage, and spikelet moisture was maintained at 0.03 g or 0.10 g H2O g-1 dry mass. The RH was checked using a WP4 T Potentiometer (Decagon Devices Inc., Pullman, WA, U.S.A.), which measures water potential (MPa), which was later converted to RH (%).

Water content (WC) was determined gravimetrically one week after the spikelets were equilibrated; four replications per treatment were placed in an oven without airflow at 105 ± 3°C for 24 h [27].

After this conditioning, the spikelets were evaluated at 90-day intervals over 12 months of storage, after which the spikelets continued to be stored, along with the lots of U. humidicola “Tully” and “Llanero” were reassessed at 44 months, and U. brizantha “Marandu” and “Basilisk”, U. ruziziensis “Kennedy” reassessed at 40 months after storage.

Seed viability

Viability was assessed by the tetrazolium test (TZ) [28], with 4 repetitions of 25 spikelets, which were placed to soak on paper moistened with water (in a proportion of 2.5 times the dry mass of the paper) for 16 hours and subsequently manually cut longitudinally and half of the spikelets immersed in a solution of 2,3,5 triphenyl tetrazolium chloride 0.1%, for 5 hours in the dark at a temperature of 40 ºC. After staining the embryos, the solution was discarded, the spikelets were washed in running water and kept in water, and the embryos were considered viable when the vital parts of the embryo were coloured red. The results were expressed as a percentage of viable spikelets.

Germination

The germination test was carried out in a germinator regulated to provide alternating temperatures (15-35ºC) and an 8-hour photoperiod without applying the method to break dormancy. The spikelets were distributed equidistantly on blotter paper in a transparent plastic box for germination, with the paper moistened with distilled water equivalent to 2.5 times the mass of the dry paper. Evaluations were carried out every 2 days from the beginning of primary root protrusion (with ± 3mm) until 21 days after sowing, and the values were expressed as a percentage.

Spikelets that did not germinate until the end of the germination test were tested for viability using the tetrazolium stain to determine the percentage of dormant spikelets (coloured by TZ) and dead spikelets (not coloured by TZ). Due to the discrepancy between the TZ test results and the germination test results, was calculate the average of these two results using the formula D= (DEG +(TZ-G))/2, where D is the percentage of dormant spikelets (%), DEG is the number of viable spikelets coloured by TZ after the germination (%), TZ is the percentage of coloured spikelets per TZ stain (%) e G is the result of the germination test (%) [8].

Statistical analysis

The experiment was conducted in a completely randomised design, with a 4 x 6 factorial arrangement (spikelet treatment x storage period), and the data were subjected to analysis of variance (ANOVA). When significant according to the F test, a grouping of means was applied using the Scott-Knott test (p ≤ 0.05) with the SISVAR package [29].

RESULTS

After splitting the spikelet fractions into light and heavy, the water content of the spikelets was determined at different RHs. There is no significant variation in WC between the fractions before the storage. However, the storage environment differed for the spikelets, independently of the fractions. The average WC of U. humidicola “Tully” initial water content (iWC) was between 10.6% and 10.8%, and during storage in an environment with RH of 4.5% and 50%, it was, respectively, 3.2% and 9.2% (Table 1). For the “Llanero”, the iWC was between 11.4% and 11.5%, reaching during storage at 4.5% and 50% RH, 3.1% to 3.2% and 9.5% to 9.7% (Table 1), respectively. The iWC for U. brizantha “Marandu” was 7% to 7.2%, but during storage, it was 4.5% to 4.6% and 10.1%, respectively, for the environment with 4.5% and 50% RH (Table 1). For “Basilisk”, the iWC was between 8.2% and 8.3%, and during storage at 4.5% and 50% RH, it was, respectively, 4.1% to 4.2% and 10.1% to 10.2% (Table 1). For U. ruziziensis “Kennedy”, the iWC was 11.8% to 12.1%; during storage, they are 4.1% to 4.3% and 9.9% to 10% in a storage environment with 4.5% and 50% RH, respectively (Table 1). There is a difference in the species' iWC, and U. brizantha has the lower iWC (Table 1).

Thumbnail
Table 1
Water content (WC) average (wet base) of the spikelets before and during storage, para L.S. = light spikelets and H.S. = heavy spikelets, in the environment with 4.5% and 50% RH

The initial germination of lots of U. humidicola “Tully” was affected by spikelet mass, with light spikelets exhibiting the lowest germination value. This performance was maintained throughout the storage period, with the size of the spikelets having a greater effect than the RH of the storage environment (Table 2). The heavy spikelets showed greater viability in the three lots of U. humidicola “Tully” during all storage periods. However, when considering the storage condition throughout the storage period, it was observed that for germination, viability and dormancy, there is a decrease in values from the third month onward (Table 2), demonstrating that, for these lots, the loss of dormancy and viability was rapid and intense. There was no time for an increase in germination for subsequent reduction, as normally occurs in studies on dormancy release and as observed in other materials from this same study (Tables 2, 3 and 4). In lots of U. humidicola “Llanero”, it was observed that an increase in germination, reduction in viability, and dormancy release occur more slowly throughout storage in this material, reaching 12 months of storage with low germination and high incidence of dormancy (Table 2). However, after 44 months of storage, the heaviest spikelets from lots 1 and 3 achieved germination above 80%, regardless of the RH of the storage environment. In lot 2, the highest germination was observed in the largest spikelets stored in an environment with 50% RH. However, in terms of viability, this lot presented a higher value for larger spikelets regardless of the environmental condition, as did lots 1 and 3 (Table 2). The smaller spikelets achieved lower germination values, around 70%. However, for the light-mass spikelets from lots 1 and 3 stored in both environments (4.5% and 50% RH), the values were 69% and 62%, respectively (Table 2).

Thumbnail
Table 2
Effect of storage period x storage condition interactions for germination, TZ viability test and spikelet dormancy of Urochloa humidicola “Tully”, lots T1, T2 and T3 and “Llanero” lots L1, L2 and L3.
Thumbnail
Table 3
Effect of storage period x storage condition interactions for germination, TZ viability test and spikelet dormancy of Urochloa brizantha “Marandu”, lots M1 and M2, and “Basilisk” lots B1, B2 and B3.
Thumbnail
Table 4
Effect of interactions of storage period x storage condition for germination, TZ viability test and spikelet dormancy of Urochloa ruziziensis “Kennedy”, lots K1 and K2.

Although there were differences between spikelets with heavy and light mass, storage conditions were satisfactory in preserving viability and releasing the dormancy, considering the results obtained at 44 months (~3.7 years) of storage. It is worth mentioning that dormancy persisted for longer in spikelets stored with lower RH (4.5%), reaching 12 months of storage with higher dormancy values than in an environment with 50% RH (Table 2). The initial evaluation of lots of U. brizantha “Marandu” showed high viability and low germination, consequently a high dormancy rate; after three months of storage, there were increases in germination, indicating that dormancy had been overcome (Table 3). Regardless of whether the light spikelets were stored at 4.5% or 50% RH, they presented the lowest viability and germination values after 40 months of storage (Table 3).

The U. brizantha “Marandu” spikelets lose dormancy faster than U. humidicola “Llanero”, taking into consideration that “Marandu”, after three months of storage, germinations are close to 70%, while in “Llanero”, after 12 months of storage, it was still very low, varying between 13% and 60%, and dormancy rates varying from 23% to 61%, therefore between “Marandu” and “Llanero”, the latter is a material that maintains dormancy for longer periods.

Although the “Marandu” cultivar exhibited dormancy release after just a few months of storage, the conditions under which the spikelets were kept were favourable to maintain the viability of the lots for up to 40 months of storage. Lot 1 maintained viability above 80% with values similar to the initial assessment. In contrast, lot 2 proved to be more sensitive to storage, especially for light spikelets, which had a viability of 59% in spikelets kept in an environment with 4.5% RH and 68% for spikelets stored at 50% RH. In comparison, heavy spikelets have 76% and 84%, respectively, when stored in an environment with 4.5% and 50% RH (Table 3).

In the initial evaluation of lots of U. brizantha “Basilisk”, it was found that initial dormancy varied between lots from 27% to 45%, and when there was a difference between storage conditions, the highest dormancy values were in light spikelets, as well as the lowest percentage of germination, and the initial viability varied between 89% and 97%, with no difference between storage conditions (Table 3). Like the “Marandu” cultivar, the “Basilisk” cultivar also showed increases in germination values and a reduction in dormancy after three months of storage for the three lots, maintaining viability until 40 months of storage, with values ranging between 75% and 94% (Table 3).

When there was a difference between the storage conditions for germination and viability, the highest percentages were obtained in heavy spikelets kept in an environment at 4.5% RH, except for lot 3, which showed a difference only concerning the mass of the spikelets (Table 3). For U. ruziziensis “Kennedy”, the initial determinations found that lot 1 had higher numerical viability and dormancy values than lot 2, with dormancy being released after 3 months of storage (Table 4).

There was an increase in germination values for lot 1 after 3 months of storage, only for light spikelets. The increase occurred after 6 months of storage for heavy spikelets, only for those stored at 50% RH. For heavy spikelets kept at 4. 5% RH, values remained almost stable for up to 40 months of storage. “Kennedy” spikelets, after 40 months of storage, achieved the highest germination percentages either in the light or in the heavy spikelets stored at 4.5% RH. The light spikelets kept at 50% RH had the lowest viability. The reduction in viability was gradual throughout storage, but the spikelets reached 40 months with a viability of nearly 80%, except for the light spikelets stored at 50% RH, which had a viability of less than 70% (Table 4).

Lot 2 in the initial evaluation showed that the heavy spikelets had higher germination and viability values than the light ones. There was no increase in germination throughout storage for this lot, except for the heavy spikelets kept in storage conditions at 50% RH; a small increase occurred after 3 months of storage, and from this period, it remained stable or with a small reduction (Table 4).

Heavy spikelets had numerically or statistically higher percentages throughout storage than light ones, reaching 40 months with germination values exceeding 60%, while light spikelets consistently fell below 45%. For viability, the heavy spikelets kept at 50% RH maintained final viability equal to the initial one, and it was also higher compared to the heavy spikelets kept at 4.5% RH, as well as among the light spikelets, regardless of the RH condition (Table 4).

DISCUSSION

The quality of the seeds must be considered when they are dried. The period for dormancy release varies between species and cultivars, and it will suffer the influence of the storage environment. Drier environments remove more water from the seeds, changing all the reactions there. So, seeds with less than 0.1 g of water g dry matter-1 did not allow any enzymatic reaction. However, it is still possible that Amadori/Maillard/Peroxidations may occur, as these reactions can occur at lower WC but at a very low velocity [33-36], and peroxide formation may act as an agent of dormancy release [8].

As observed in U. humidicola “Tully” and “Llanero”, the time for dormancy release as well as the loss of viability is also variable, with the “Tully” cultivar being the most sensitive to storage or due to the lots having low initial vigour, most probably because the spikelets are harvested in the panicle and they are not complete mature, leading to a deterioration faster than the after ripening [30]. The poor quality of “Tully” spikelets is related to the early harvesting method used to collect them mechanically from panicles, which occurs when many immature ones are still present. The process cannot be delayed to wait for all the spikelets to mature, as natural shattering occurs in this crop, leading to the fall of spikelets that have reached maturity [31]. Because late seed maturation is essential for the accumulation of many substances that are key to seed drying (desiccation tolerance, defence, and repair mechanisms), it confers longevity to the seeds. Before that phase, the embryo may tolerate desiccation but with a short lifespan and high ABA content, which prevents germination [30]. All other materials were mechanically swept from the soil, meaning that they reached full maturation.

Seed immaturity and longevity affect seed quality; immature seeds do not complete dry matter and have incomplete biosynthesis, abscisic acid is still acting, as seed quality is acquired sequentially during seed development and maturation [32]. Although the seed reaches its maximum dry mass during maturity, longevity is gradually gained during the late maturation phase [30]. Studies have shown that in several species, such as Medicago trunculata, Oryza sativa and Arabidopsis thaliana, there was a significant 30 to 50-fold increase in seed longevity [33-35] as the dry matters of seeds rise and this could be an explanation of why light seeds (half-filled) performed worse during storage than heavy seeds, as they flower and mature differently in the field [23,36].

The moisture content of the spikelets and relative humidity, maintained at a temperature of 20ºC±3ºC, were favourable for dormancy release during storage and preserving spikelet viability, as all materials reached 40 or 44 months with high germination values and viability for heavy spikelets, except U. humidicola “Tully”.

The results observed in this research with the “Llanero” contradict those found in Arabidopsis thaliana mutants [37], which indicate that high storability is correlated with superficial seed dormancy. Low storability is associated with high levels of seed dormancy, perhaps because A. thaliana does not exhibit shattering. The more well-formed the seeds were, the less dormancy they exhibited. As shown here, all lots of “Llanero” had a dormancy rate above 60%, and after 44 months of storage (~3.6 years), these lots exhibited germination and viability rates over 70% in most of the storage conditions studied. The “Kennedy” lots exhibited initial dormancy at a level comparable to that of “Llanero”. At 40 months, germination and viability were higher than those observed in “Llanero”. One possible cause is the accumulation of peroxides in those seeds [8]. Therefore, there is still much to be investigated regarding the correlation between dormancy and seed storability. Other studies have shown that temperature, seed moisture content and relative humidity affect the dormancy release during storage and seed viability [8,24,25,38-40].

In other species of the Poaceae family, such as Avena fatua L. (wild oats), it was found that as the temperature decreased, the moisture content of the seed necessary for after-ripening to occur increased, e.g., at 40 ºC, the moisture content required was 10-12% and at 30ºC it was 14-20%, in 3 months of storage [41]. The dormancy release in wild Oryza sativa (weedy rice) seeds occurs shortly after maturation, with a seed moisture content of 6-14% at 25°C, and a duration of 1.5 months [46]. At 30 ºC, the seed moisture content was 10.8%, and the time required was 2 months [42]. Relative humidity is important when storing seeds, as they are hygroscopic, and the higher the relative humidity of the environment, the higher the equilibrium moisture content of the seeds [43] which leads to seed respiration and over accumulation of ROS and to seed deterioration but a certain amount of ROS act as signal for dormancy release, above this deterioration occurs, bellow that dormancy is active [14,16].

The impact of storage conditions has been studied in many cereals [44,45] stored under conventional seed bank conditions (-20 ºC and 5% RH) with an extended conservation and in non-conventional conditions (20 ºC and ~50% RH) with seeds rich in carbohydrates with an extended time of storage (~20 years) and lipid rich seeds with the short lifespan (~6 years) [46]. The longevity of Sorghum bicolor (sorghum), Lens culinaris (lentil) and Guizotia abyssinica (niger) seeds stored at variable RH and temperatures for 3 months resulted in increasing deterioration independent of the seed species at high temperature and RH. Storage at 95 and 75% RH and 35 ºC quickly reduced the germination and vigour index for all seed varieties. Stored seeds at low RH and temperature (10 ºC) have proven beneficial in maintaining seed viability and vigour [47].

Light and heavy spikelets differed in storage, with the heavy ones achieving better conservation because they completed the cycle, reaching final maturation. The light ones failed to reach the maturation phase and are more sensitive to storage. In Saccharum ravenae, a similar effect occurred, with the heavier seeds germinating faster and in a higher proportion than the lighter ones [48]. This is connected with the accumulation of reserves, acquisition of desiccation tolerance, and functional repair mechanisms that are primarily present in fully mature seeds [30].

CONCLUSION

The dormancy of U. humidicola “Llanero” remained high up to 12 months of storage, as did that of Urochloa spp. “Marandu”, “Basilisk”, and ‘Kennedy’ break dormancy after up to three months of storage, and U. humidicola “Tully had a fast dormancy release and lost viability, especially on light seeds.

Seeds of “Llanero”, “Marandu”, “Basilisk”, and “Kennedy” at low moisture content and 20 °C, preserve well under storage, maintaining seed viability for up to three years.

  • Funding:
    This research did not receive any external funding.

Acknowledgements:

We would like to thank CAPES (Improvement of Higher Education Personnel) for the FLA for postdoctoral fellowship and CNPq grant number 302426/2023-0 to NBMN UNOESTE.

Data availability statement:

Research data are only available upon request for corresponding author.

REFERENCES

  • 1 Baskin CC, Baskin JM. Seeds: ecology, biogeography and evolution of dormancy and germination. 2nd ed. San Diego, CA, USA: Academic Press; 2014.
  • 2 Baskin JM, Baskin CC. The great diversity in kinds of seed dormancy: a revision of the Nikolaeva-Baskin classification system for primary seed dormancy. Seed Sci Res [Internet]. 2021 [cited 2024 Mar 1];31(4):249-277.
  • 3 Purugganan MD. Evolutionary insights into the nature of plant domestication. Current Biol [Internet]. 2019 [cited 2024 Apr 7];29(14):R705-R714.
  • 4 Adkins SW, Bellairs SM, Loch DS. Seed dormancy mechanisms in warm season grass species. Euphytica [Internet]. 2002 [cited 2024 May 3];126:13-20.
  • 5 Hampton JG. Forage seed quality: dormancy, standards and quarantine. 2015 [cited 2024 May 3];
  • 6 Baskin CC, Baskin JM. Breaking seed dormancy during dry storage: a useful tool or major problem for successful restoration via direct seeding? Plants [Internet]. 2020 [cited 2024 Mar 1];9(5):636.
  • 7 Sano N, Rajjou L, North HM, Debeaujon I, Marion-Poll A, Seo M. Staying alive: molecular aspects of seed longevity. Plant and Cell Physiol [Internet]. 2016 [cited 2024 Jun 12];57(4):660-674.
  • 8 Abrantes FL, Machado-Neto NB, Custódio CC. Seed moisture content can be used to accelerate dormancy release during after-ripening of Urochloa humidicola cv. Llanero spikelets. Ciência Rural [Internet]. 2020 [cited 2024 Apr 30];51:e20200526.
  • 9 Boyd N, Acker RV. Seed germination of common weed species as affected by oxygen concentration, light, and osmotic potential. Weed Sci [Internet]. 2004 [cited 2024 May 4];52(4):589-596.
  • 10 Bykova NV, Hu J, Ma Z, Igamberdiev AU. The Role of Reactive Oxygen and Nitrogen Species in Bioenergetics, Metabolism, and Signaling During Seed Germination. In: Gupta KJ, Igamberdiev AU, editors. Reactive Oxygen and Nitrogen Species Signaling and Communication in Plants [Internet]. Cham: Springer International Publishing; 2015 [cited 2024 May 4]. p. 177-195. Available from: https://link.springer.com/10.1007/978-3-319-10079-1_9
    » https://link.springer.com/10.1007/978-3-319-10079-1_9
  • 11 Corbineau F. Oxygen, a key signalling factor in the control of seed germination and dormancy. Seed Sci Res [Internet]. 2022 [cited 2024 May 4];32(3):126-136.
  • 12 Penfield S. Seed dormancy and germination. Cur Biol[Internet]. 2017 [cited 2024 May 4];27(17):R874-R878.
  • 13 Bailly C. The signalling role of ROS in the regulation of seed germination and dormancy. Biochem J [Internet]. 2019 [cited 2022 Feb 6];476(20):3019-3032.
  • 14 Bailly C, Merendino L. Oxidative signalling in seed germination and early seedling growth: An emerging role for ROS trafficking and inter-organelle communication. Biochem J [Internet]. 2021 [cited 2024 May 1];478(10):1977-1984.
  • 15 El-Maarouf-Bouteau H, Bailly C. Oxidative signaling in seed germination and dormancy. Plant Signal & Behav. 2008;3(3):175-182.
  • 16 Foyer CH, Ruban AV, Noctor G. Viewing oxidative stress through the lens of oxidative signalling rather than damage. Portland Press Limited; 2017.
  • 17 Bailly C, El-Maarouf-Bouteau H, Corbineau F. From intracellular signaling networks to cell death: the dual role of reactive oxygen species in seed physiology. Comptes Rendus Biol [Internet]. 2008 [cited 2024 May 1];331(10):806-814.
  • 18 Chahtane H, Kim W, Lopez-Molina L. Primary seed dormancy: a temporally multilayered riddle waiting to be unlocked. J Experiment Bot. 2017 [cited 2024 May 3];68(4):857-869.
  • 19 Dekkers BJ, Pearce SP, van Bolderen-Veldkamp RPM, et al. Dormant and after-ripened Arabidopsis thaliana seeds are distinguished by early transcriptional differences in the imbibed state. Fronn Plant Sci [Internet]. 2016 [cited 2024 May 3];7:215724.
  • 20 Nelson SK, Ariizumi T, Steber CM. Biology in the Dry Seed: Transcriptome Changes Associated with Dry Seed Dormancy and Dormancy Loss in the Arabidopsis GA-Insensitive sleepy1-2 Mutant. Front Plant Sci [Internet]. 2017 [cited 2024 May 3];8:2158.
  • 21 Tilini KL, Meyer SE, Allen PS. Breaking primary seed dormancy in Gibbens’ beardtongue (Penstemon gibbensii) and blowout penstemon (Penstemon haydenii). Native Plants Jl [Internet]. 2016 [cited 2024 May 3];17(3):256-266.
  • 22 Zhang LW, Liu HL, Zhang DY, Byan WG. Seed dormancy release and germination characteristics of Corispermum lehmannianum Bunge, an endemic species in the Gurbantunggut desert of China. Phyton [Internet]. 2015 [cited 2024 May 3];84:58-63.
  • 23 Hay FR, Probert RJ. Advances in seed conservation of wild plant species: a review of recent research. Conservation Physiol [Internet]. 2013 [cited 2024 May 29];1(1):cot030.
  • 24 Steadman KJ, Crawford AD, Gallagher RS. Dormancy release in Lolium rigidum seeds is a function of thermal after-ripening time and seed water content. Functional Plant Biol [Internet]. 2003 [cited 2024 May 3];30(3):345-352.
  • 25 Chhabra R, Singh T. Seed aging, storage and deterioration: An irresistible physiological phenomenon. Agric Rev [Internet]. 2019 [cited 2024 May 3];40(3):234-238.
  • 26 Hay FR, Adams J, Manger K, Probert R. The use of non-saturated lithium chloride solutions for experimental control of seed water content. Seed Sci Technol. 2008 [cited 2024 May 3];36(3):737-746.
  • 27 BRASIL. Regras para análise de sementes. Brasília: Ministério da Agricultura, Pecuária e Abastecimento; 2009 [cited 2024 May 3].
  • 28 Custódio CC, Damasceno RL, Machado Neto NB. Imagens digitalizadas na interpretação do teste de tetrazólio em sementes de Brachiaria brizantha Rev Bras Sementes [Internet]. 2012;34(2):334-341.
  • 29 Ferreira DF. Sisvar: a computer statistical analysis system. Ciência e agrotecnologia. 2011 [cited 2024 May 3];35(6):1039-1042.
  • 30 Leprince O, Pellizzaro A, Berriri S, Buitink J. Late seed maturation: drying without dying. J Experiment Bot [Internet]. 2017 [cited 2024 Mar 29];68(4):827-841.
  • 31 Souza FHD de, Verzignassi JR, Peres RM, et al. Produção comercial de sementes de Brachiaria (syn. Urochloa) humidicola no Brasil. 2016 [cited 2024 Nov 26]; http://www.alice.cnptia.embrapa.br/alice/handle/doc/1053458
    » http://www.alice.cnptia.embrapa.br/alice/handle/doc/1053458
  • 32 Matthews S, Noli E, Demir I, Khajeh-Hosseini M, Wagner M-H. Evaluation of seed quality: from physiology to international standardization. Seed Sci Resh. 2012 [cited 2024 May 3];22(S1):S69-S73.
  • 33 Hay FR, Timple S, van Duijn B. Can chlorophyll fluorescence be used to determine the optimal time to harvest rice seeds for long-term genebank storage? Seed Sci Resh [Internet]. 2015 [cited 2024 May 3];25(3):321-334.
  • 34 Righetti K, Vu JL, Pelletier S, et al. Inference of longevity-related genes from a robust coexpression network of seed maturation identifies regulators linking seed storability to biotic defense-related pathways. The Plant Cell [Internet]. 2015 [cited 2024 May 15];27(10):2692-2708.
  • 35 Verdier J, Lalanne D, Pelletier S, et al. A regulatory network-based approach dissects late maturation processes related to the acquisition of desiccation tolerance and longevity of Medicago truncatula seeds. Plant Physiol [Internet]. 2013 [cited 2024 May 15];163(2):757-774.
  • 36 de Souza FHD, Peres RM, Coutinho Filho JLV, Justo CL. Manejo de campos de produção de sementes de Urochloa humidicola ’comum’: II-efeito de práticas culturais. 2015 [cited 2024 Nov 26]; https://www.alice.cnptia.embrapa.br/alice/handle/doc/1033828
    » https://www.alice.cnptia.embrapa.br/alice/handle/doc/1033828
  • 37 Nguyen T-P, Keizer P, van Eeuwijk F, Smeekens S, Bentsink L. Natural variation for seed longevity and seed dormancy are negatively correlated in Arabidopsis Plant Physiol [Internet]. 2012 [cited 2024 May 3];160(4):2083-92.
  • 38 Fleming MB, Hill LM, Walters C. The kinetics of ageing in dry-stored seeds: A comparison of viability loss and RNA degradation in unique legacy seed collections. Ann Boty. 2019 [cited 2024 May 3];123(7):1133-46.
  • 39 Walters C, Hill LM, Wheeler LJ. Dying while dry: kinetics and mechanisms of deterioration in desiccated organisms. Integr Comp Biol. 2005 [cited 2024 May 3];45(5):751-8.
  • 40 Basbouss-Serhal I, Leymarie J, Bailly C. Fluctuation of Arabidopsis seed dormancy with relative humidity and temperature during dry storage. J Experiment Bot [Internet]. 2016 [cited 2024 May 3];67(1):119-30.
  • 41 Foley ME. Temperature and water status of seed affect afterripening in wild oat (Avena fatua). Weed Sci [Internet]. 1994 [cited 2024 May 3];42(2):200-4.
  • 42 Gianinetti A, Cohn MA. Seed dormancy in red rice. XIII: Interaction of dry-afterripening and hydration temperature. Seed Sci Res [Internet]. 2008 [cited 2024 May 3];18(3):151-9.
  • 43 Marcos Filho J. Seed vigor testing: an overview of the past, present and future perspective. Scientia Agric. 2015 [cited 2024 May 3];72(4):363-74.
  • 44 Nagel M, Vogel H, Landjeva S, Buck-Sorlin G, Lohwasser U, Scholz U. et al. Seed conservation in ex situ genebanks-genetic studies on longevity in barley. Euphytica. 2009 [cited 2024 May 3];170(1-2):5-14.
  • 45 Nagel M, Kranner I, Neumann K, et al. Genome-wide association mapping and biochemical markers reveal that seed ageing and longevity are intricately affected by genetic background and developmental and environmental conditions in barley. Plant, Cell & Environ. 2015 [cited 2024 May 3];38(6):1011-22.
  • 46 Nagel M, Börner A. The longevity of crop seeds stored under ambient conditions. Seed Sci Res. 2010 [cited 2024 May 3];20(1):1-12.
  • 47 Assefa F, Srinivasan K. Effect of relative humidity and temperature on shelf life of sorghum, lentil and niger seeds. Int J Appl Agric Sci. 2016 [cited 2024 May 3];2(6):83-91.
  • 48 Springer T l., Goldman J. Germination of Saccharum ravennae (L.) L. (Poaceae) Caryopses and Intact Spikelets. Crop Sci [Internet]. 2016 [cited 2025 Jun 24];56(2):682-8.
  • Editor-in-Chief:
    Bill Jorge Costa
  • Associate Editor:
    Adriel Ferreira da Fonseca

Publication Dates

  • Publication in this collection
    06 Oct 2025
  • Date of issue
    2025

History

  • Received
    28 Nov 2024
  • Accepted
    06 Aug 2025
Creative Common - by 4.0
This is an article published in open access under a Creative Commons license.
location_on
Instituto de Tecnologia do Paraná - Tecpar Rua Prof. Algacyr Munhoz Mader, 3775 - CIC, 81350-010 , Tel: +55 41 3316-3054 - Curitiba - PR - Brazil
E-mail: babt@tecpar.br
rss_feed Stay informed of issues for this journal through your RSS reader
Report error