Seed Dormancy in Hairy Vetch (Vicia villosa Roth) Is Influenced by Genotype and Environment

Seed dormancy complicates the agricultural use of many legume species. Understanding the genetic and environmental drivers of seed dormancy is necessary for advancing crop improvement for legumes, such as Vicia villosa. In this study, we quantify the magnitude of genetic and environmental effects on physical dormancy among 1488 maternal V. villosa plants from 18 diverse environments. Furthermore, we explore the relationship between physical dormancy and environmental conditions during seed development. Additive genetic variance (h2) accounted for 40% of the variance, while the growing environment explained 28% of the variance in physical dormancy. Maternal lines showed complete variance in physical dormancy, as one line was 100% dormant, and 56 lines were 0% dormant. Distributions of physical dormancy varied widely among seed production environments, with some site-years strongly skewed toward physically dormant seed, while other site-years exhibited little dormant seed. Twenty-three weather variables were associated with environmental and error effects of physical dormancy. High mean and minimum relative humidity, low mean and maximum temperature, and high precipitation weakly grouped with low physical dormancy. Weather variables calculated from fixed time windows approximating seed maturity to seed harvest at each site-year tended to be less predictive than biological seed drying windows calculated based on seed maturity of each maternal line. Overall, individual and cumulative effects of weather variables were poor predictors of physical dormancy. Moderate heritability indicates that breeding programs can select against physical dormancy and improve V. villosa for agricultural use. Marker-based approaches would maximize selection for physical dormancy by reducing the influence of unpredictable environmental effects.

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Spontaneous Gene Flow between Cultivated and Naturalized Vicia villosa Roth Populations Increases the Physical Dormancy Seed in a Semiarid Agroecosystem

Agronomy ◽

10.3390/agronomy11050955 ◽

2021 ◽

Vol 11 (5) ◽

pp. 955

Author(s):

Juan Pablo Renzi ◽

Omar Reinoso ◽

Matías Quintana ◽

Petr Smýkal

Keyword(s):

Gene Flow ◽

Seed Dormancy ◽

Cover Crops ◽

Farming Systems ◽

Physical Dormancy ◽

Vicia Villosa ◽

Ley Farming ◽

Initial Generation ◽

Plant Maturity ◽

Cultivated Populations

Hairy vetch (Vicia villosa Roth) is the second most cultivated vetch worldwide being used as a forage and cover crop. As it is not domesticated, it displays several wild traits including seed dormancy. The physical seed dormancy (PY) variation could be useful depending on the specific context. High PY is desirable for ley farming systems, while low PY is needed to prevent weediness in subsequent crop rotations. Gene flow between cultivated and naturalized populations has important ecological and agronomic consequences. Experiments were conducted to determine the change in the level of PY in spontaneous crosses between European cultivated accessions (EU) characterized by low PY and naturalized Argentinian population (AR) with high PY. Generations G0 (initial generation) to G3 were assessed for their PY in seeds and total dry matter (DM) per plot, at plant maturity. As the result of spontaneous crosses with the AR population, an increase from G0 to G3 in PY and DM in EU accessions was observed, while AR maintained its high PY and DM values. In one mating cycle, selecting for PY lower than 14% and high DM can satisfy breeding objectives for cover crops. Isolation during breeding and seed production is necessary to avoid gene flow. This knowledge extends to other legume species with gene flow between wild and cultivated populations.

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Seed dormancy in four Tibetan Plateau Vicia species and characterization of physiological changes in response of seeds to environmental factors

Seed Science Research ◽

10.1017/s0960258513000019 ◽

2013 ◽

Vol 23 (2) ◽

pp. 133-140 ◽

Cited By ~ 14

Author(s):

Xiaowen Hu ◽

Tingshan Li ◽

Juan Wang ◽

Yanrong Wang ◽

Carol C. Baskin ◽

...

Keyword(s):

Tibetan Plateau ◽

Seed Dormancy ◽

Germination Rate ◽

Soil Surface ◽

The Tibetan Plateau ◽

Physical Dormancy ◽

High Germination ◽

One Year ◽

Hydrotime Model ◽

Aba Biosynthesis

AbstractAlthough seed dormancy of temperate legumes is well understood, less is known about it in species that grow in subalpine/alpine areas. This study investigated dormancy and germination of four Vicia species from the Tibetan Plateau. Fresh seeds of V. sativa were permeable to water, whereas those of V. angustifolia, V. amoena and V. unijuga had physical dormancy (PY). One year of dry storage increased the proportion of impermeable seeds in V. angustifolia, but showed no effect on seed coat permeability in V. amoena or V. unijuga. Seeds of all four species also had non-deep physiological dormancy (PD), which was especially apparent in the two annuals at a high germination temperature (20°C). After 1 year of storage, PD had been lost. The hydrotime model showed that fresh seeds obtained a significantly higher median water potential [Ψb(50)] than stored seeds, implying that PD prevents germination in winter for seeds dispersed without PY when water availability is limited. After 6 months on the soil surface in the field, a high proportion of permeable seeds remained ungerminated, further suggesting that PD plays a key role in preventing germination after dispersal. Addition of fluridone, an inhibitor of abscisic acid (ABA) biosynthesis, evened-out the differences in germination between fresh and stored seeds, which points to the key role of ABA biosynthesis in maintaining dormancy. Further, fresh seeds were more sensitive to exogenous ABA than stored seeds, indicating that storage decreased embryo sensitivity to ABA. On the other hand, the gibberellic acid GA3 increased germination rate, which implies that embryo sensitivity to GA is also involved in seed dormancy regulation. This study showed that PY, PD or their combination (PY+PD) plays a key role in timing germination after dispersal, and that different intensities of dormancy occur among these four Vicia species from the Tibetan Plateau.

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Effects of Different Pretreatments and Seed Coat on Dormancy and Germination of Seeds of Senna obtusifolia (L.) H.S. Irwin & Barneby (Fabaceae)

International Journal of Biology ◽

10.5539/ijb.v8n2p77 ◽

2016 ◽

Vol 8 (2) ◽

pp. 77

Author(s):

Stephen I. Mensah ◽

Chimezie Ekeke

Keyword(s):

Sulfuric Acid ◽

Seed Dormancy ◽

Water Uptake ◽

Seed Coat ◽

Critical Factor ◽

Potassium Nitrate ◽

Ex Situ ◽

Mechanical Resistance ◽

Physical Dormancy ◽

Senna Obtusifolia

The seed dormancy of Senna obtusifolia was investigated through various methods, namely pretreatments in concentrated sulfuric acid, 2% potassium nitrate (KNO3), 99% ethanol, 99% methanol, and in hydrogen perioxide; examination of the seed coverings; and the determination of water uptake by the seeds in order to ascertain the most effective technique for breaking dormancy and also determine the dormancy type. The results showed that sulfuric acid treatment recorded the highest germination (100%); followed by 2% hydrogen peroxide treatment (24%) in 15minutes immersion. The methanol and ethanol pretreatments gave 18.33% and 16.5% germinations respectively. Pretreatment in 2% potassium nitrate gave the lowest germination (8.50%), while the intact seeds of S. obtusifiolia (control) gave 0% germination. The anatomy of the seed coat indicated the presence of hard, thickened and specialized cells of cuticle, macrosclereids, osteoscereids, and disintegrated parenchyma layers. The water uptake of intact seeds was low (13.5%) after 24 hr imbibitions. These findings revealed that the seed coat acts as barrier to germination by preventing water absorption, possibly gaseous diffusion in and out of the seed and conferring mechanical resistance to the protrusion of embryo. Pretreatments, such as immersion in H2SO4 will soften the seed coat and permit germination. Seed dormancy in S. obtusifolia can be considered of physical nature and classified as physical dormancy. The results obtained in this study may serve as useful information in the production and improvement of S. obtusifolia seedlings, as knowledge on seed dormancy and germination is a critical factor and requirements to the understanding of the propagation of this plant either in situ or ex-situ, in view of the economic potentials/attributes of this species.

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Variations in seed dormancy and rates of development of great brome, Bromus diandrus Roth., as adaptations to the climates of southern Australia and implications for weed control

Australian Journal of Agricultural Research ◽

10.1071/ar9850295 ◽

1985 ◽

Vol 36 (2) ◽

pp. 295 ◽

Cited By ~ 23

Author(s):

GS Gill ◽

WM Blacklow

Keyword(s):

Seed Dormancy ◽

Cropping Systems ◽

Storage Conditions ◽

Environment Interaction ◽

Dormant Seed ◽

Field Site ◽

Bromus Diandrus ◽

Genotype X Environment ◽

The Common ◽

Common Field

Seeds of great brome, B. diandrus, were collected from 14 sites across southern Australia and sown at Perth, W.A. The duration of seed dormancy varied among the seed accessions when produced at the common field site of Perth, which suggested that variations in dormancy were genetically controlled. The environment of Perth shortened the duration of dormancy in all the accessions but did not affect their ranking, indicating a lack of genotype x environment interaction. The duration of dormancy was positively correlated (r = 0.78) with the duration of the rain-free summers of the site of collection. Dormancy was not due to hard-seededness and non-dormant seeds germinated within 40 h of wetting at 20�C. The seed dormancy was limited to about 5 months under the storage conditions examined. Dormant seed was stimulated to germinate by gibberellic acid (2.89 mM) and dormant seed of the accession from Geraldton also responded to removal of the lemma and palea or to leaching with water. The time taken for accessions to 'panicle peep' was positively correlated (r = 0.83) with the length of the rainy winters of the sites of collection. The results show great brome has adapted genetically to the climate of southern Australia. Cropping systems that exploit the lack of residual dormancy and the potential for rapid and complete germination s

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Overcoming seed dormancy and rooting in air-layering polyembryonic seedlings of sapucaia (Lecythis pisonis Cambess.)

Australian Journal of Crop Science ◽

10.21475/ajcs.20.14.05.p2262 ◽

2020 ◽

pp. 816-821

Author(s):

Caroline Palacio de Araujo ◽

Rodrigo Sobreira Alexandre ◽

Thuanny Lins Monteiro Rosa ◽

Edilson Romais Schmildt ◽

José Carlos Lopes ◽

...

Keyword(s):

Seed Dormancy ◽

Seed Coat ◽

Block Design ◽

Adjacent Region ◽

Physical Dormancy ◽

Functional Elements ◽

Lateral Region ◽

Design Environments ◽

Randomized Complete Block Design ◽

Edible Seeds

Lecythis pisonis produces edible seeds rich in nutritional and functional elements such as selenium and are a great alternative to Brazilian nuts. The seeds have low germination, which may be related to physical dormancy imposed by tegument, meaning that polyembryonic seedlings can be a strategy to increase final stand. The objective of this work was to study methods to overcome seed dormancy and auxin induction in polyembryonic seedlings of pisonis. The experiment to break dormancy consisted of seven treatments: T1: intact seeds; T2: seeds scarified on hilum’s opposite side; T3: seeds scarified hilum’s adjacent region; T4: seeds scarified in lateral region; T5: seeds scarified in both opposite and adjacent region to the hilum; T6: T2 + immersion in water at 40 °C/20 minutes; T7: T2 + immersion in water at 60 °C/5 minutes. The experiment to induce rooting was arranged in a 2 x 6 factorial randomized complete block design (environments: A. greenhouse and B. greenhouse covered with black polyolefin (80% shading) x concentrations of indole-3-butyric acid (IBA): 0; 1000; 2000; 3000; 4000 and 5000 mg L-1), with four replicates of eight polyembryonic seedlings. Seed coat scarification in hilum’s adjacent (T3) and lateral regions (T4) was the most efficient methods for breaking physical dormancy. IBA at 5000 mg L-1 promoted the greatest rhizogenesis of L. pisonis layers.

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Seed Dormancy Breaking and Germination in Bituminaria basaltica and B. bituminosa (Fabaceae)

Plants ◽

10.3390/plants9091110 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1110 ◽

Cited By ~ 1

Author(s):

Francesca Carruggio ◽

Andrea Onofri ◽

Carmen Impelluso ◽

Gianpietro Giusso del Galdo ◽

Giovanni Scopece ◽

...

Keyword(s):

Seed Dormancy ◽

Dormancy Breaking ◽

Physical Dormancy ◽

Palisade Cell ◽

Mediterranean Populations ◽

Seed Collection ◽

Maturity Stages ◽

Storage Times ◽

And Storage

Most legumes are well-known for the physical dormancy of their seeds; hence, the implementation of appropriate scarification techniques is essential for introducing new legume crops within agricultural systems. This study investigated morpho-anatomical traits and dormancy-breaking requirements in two taxa of the genus Bituminaria: the widespread B. bituminosa and the point endemic B. basaltica. As the species under investigation show monospermic indehiscent legumes, pods were used in this research. We performed pod trait measurements, light microscopy observations on the seed coat anatomical structure, and germination tests after mechanical, thermal, and chemical scarification treatments for seed dormancy breaking. Moreover, germination performance at different pod maturity stages and storage times was tested. Differences in morpho-anatomical traits were found, with B. basaltica having a thicker palisade cell layer and B. bituminosa showing larger pods. All of the scarification treatments proved to be able to break physical dormancy, with mechanical and chemical scarification being the most effective methods in both species. Nevertheless, dormancy-breaking treatments performed better in B. bituminosa. Seeds at early pod maturity stages showed higher germination capacity in both species. Overall, this research provided background knowledge on seed collection time, storage strategy, and effective pre-sowing treatment, which might contribute to enhance propagation and use of Bituminaria species for multiple purposes. Under this perspective, the future characterization of additional Bituminaria genetic resources from other Mediterranean populations will have remarkable importance.

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Development of a thermal-time model for combinational dormancy release of hairy vetch (Vicia villosa ssp. villosa)

Crop and Pasture Science ◽

10.1071/cp13430 ◽

2014 ◽

Vol 65 (5) ◽

pp. 470 ◽

Cited By ~ 11

Author(s):

Juan P. Renzi ◽

Guillermo R. Chantre ◽

Miguel A. Cantamutto

Keyword(s):

Model Development ◽

Thermal Time ◽

Hairy Vetch ◽

Physical Dormancy ◽

Time Model ◽

Vicia Villosa ◽

Mechanism Model ◽

Time Requirements ◽

Size Threshold ◽

Time Accumulation

Seed dormancy could be a factor related to natural reseeding of hairy vetch (Vicia villosa ssp. villosa Roth.), a winter annual species cultivated for seed, pasture, hay, green manure and cover crop. The presence of combinational dormancy (physical dormancy + physiological dormancy, PY + PD) in hairy vetch was explored by a model using laboratory and field measures. At the stage of natural dispersal, dry seeds of hairy vetch were stored under laboratory conditions at 5, 10, 20 and 30°C (±2°C) or buried at 5 cm depth in an experimental field. Germination at 5, 8, 10, 15, 20 and 25°C was assessed at regular intervals up to 295 days after harvest. Following the hypothesis of the existence of a combinational dormancy mechanism, model development was based on the estimation of: (i) the fraction of non-PY seed as a function of after-ripening thermal-time accumulation, and (ii) seed population thermal parameters associated with a given level of PD. The developed model adequately described the after-ripening thermal-time requirements for PY + PD release of V. villosa. Based on model predictions, under a semi-arid thermal regime, >45% of vetch seeds shed during the summer season would be able to germinate during early autumn. Thus, the seed-bank size threshold at the end of the first growing season should be >65 seeds m–2 in order to reach a minimum stand of 30 plants m–2 necessary for a productive pasture.

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Variation in Piceaglauca seed germination associated with the year of cone collection

Canadian Journal of Forest Research ◽

10.1139/x93-167 ◽

1993 ◽

Vol 23 (7) ◽

pp. 1306-1313 ◽

Cited By ~ 7

Author(s):

G.E. Caron ◽

B.S.P. Wang ◽

H.O. Schooley

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Storage Period ◽

White Spruce ◽

Germination Percentage ◽

Degree Days ◽

Seed Maturity ◽

Individual Trees ◽

Collection Time

The effects of cone storage period and pregermination treatment on seed maturity and dormancy were compared for cones of white spruce (Piceaglauca (Moench) Voss) collected from individual trees in 1984 and 1988. Seeds were extracted from cones and germinated after 2 or 6 weeks of cone storage in 1984 and after 2, 4, 6, 10, or 14 weeks in 1988. Based on cumulative degree-days, seeds were more mature at collection time in 1988 than in 1984. Seeds from 1984 cones stored for 6 weeks matured during storage, and both germination percentage (GP) and rate of germination (GR) were significantly improved. In contrast, storage up to 14 weeks in 1988 did not increase GP and GR, as seed had attained maturity prior to cone collection. Seed dormancy was present in both 1984 and 1988. Significant improvements in GP and GR were achieved in 1984 with a pregermination treatment even before seed maturity was attained. Prechilling of seed after 6 weeks of cone storage increased GP from 60 to 95% in 1984 and 64 to 89% in 1988.

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Use of Weather Variables to Quantify Sorghum Ergot Potential in South Africa

Plant Disease ◽

10.1094/pdis.1998.82.1.26 ◽

1998 ◽

Vol 82 (1) ◽

pp. 26-29 ◽

Cited By ~ 17

Author(s):

N. W. McLaren ◽

B. C. Flett

Keyword(s):

Minimum Temperature ◽

Pollen Viability ◽

Breakdown Point ◽

Field Trials ◽

Maximum Temperature ◽

Daily Maximum Temperature ◽

Daily Maximum ◽

Weather Variables ◽

Data Set ◽

Study Results

Quantification of resistance to ergot requires that the observed ergot severity within a sorghum line be compared with expected ergot severity (ergot potential) to compensate for differences in environmental favorability for the disease among flowering dates and seasons. The ergot potential required to induce the onset of disease is referred to as the ergot breakdown point of that line. In earlier studies, the ergot potential of a specific flowering date was defined as the mean ergot severity in all sorghum heads over all lines in the nursery which commenced flowering on that date in a genetically broad-based sorghum nursery. In this study, results of field trials enabled accurate prediction of ergot potential by using a multiple regression analysis which included three weather variables—namely, pre-flowering minimum temperature (mean of days 23 to 27 pre-flowering), mean daily maximum temperature, and mean daily maximum relative humidity (mean of days 1 to 5 post-flowering; R2 = 0.90; P = 0.91E-5). Evaluation of predicted and observed ergot severity in an independent data set gave an index of agreement of d = 0.94 and R2 = 0.84 (P = 0.106E-4), showing that ergot severity, assuming the presence of viable inoculum, can be accurately predicted. Low pre-flowering minimum temperature was associated with reduced pollen viability, which appeared to be the primary factor predisposing lines to ergot.

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Seed dormancy in the early diverging eudicot Trochodendron aralioides (Trochodendraceae)

Seed Science Research ◽

10.1079/ssr2005235 ◽

2006 ◽

Vol 16 (1) ◽

pp. 71-75 ◽

Cited By ~ 3

Author(s):

Jerry M. Baskin ◽

Carol C. Baskin ◽

Ching-Te Chien ◽

Shun-Ying Chen

Keyword(s):

Seed Dormancy ◽

Seed Plants ◽

Seed Length ◽

Seed Maturity ◽

Early Tertiary ◽

Radicle Emergence ◽

Primitive Condition ◽

Embryo Length ◽

Morphological Dormancy

The embryo length/seed length (E/S) ratio of the early diverging eudicot Trochodendron aralioides is 0.34. Embryos in fresh seeds were 0.36±0.01 mm long, and they increased in length by about 250% (in 20 d) before radicle emergence (germination) occurred, demonstrating that the embryo is underdeveloped at seed maturity. Seeds germinated to 95–100% at 20/10, 25/15 and 30/15°C in light in ≤4 weeks, without any pretreatment, but no seeds germinated in darkness. Thus, seeds of T. aralioides have morphological dormancy (MD), which is considered to be the primitive condition in seed plants, and MD probably has existed in the genus Trochodendron since its origin in the early Tertiary.

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