Competition studies in diploid and tetraploid varieties of Lolium perenne: 1. The influence of density and proportion of sowing

1977 ◽  
Vol 88 (2) ◽  
pp. 405-410 ◽  
Author(s):  
J. Norrington-Davies ◽  
J. H. Harries
Keyword(s):  
Binary Mixture ◽  
Lolium Perenne ◽  
Significant Variation ◽  
Germination Percentage ◽  
Pure Stand ◽  
Germination Inhibitors ◽  
Germination Time ◽  
Mean Germination Time ◽  
The Mean ◽  
Seed Coats

SUMMARYTwo varieties of Lolium perenne, the diploid Hora and the tetraploid Terhoy were sown either as a pure stand or as a binary mixture on to the surface of multipots filled with a standard John Innes compost. Density of sowing was varied over the range of 16, 24, 36, 50 and 100 seeds/pot. There were four replicates. The pattern of germination was followed over a period of 14 days when it was found that (i) the varieties did not differ in their germination when grown alone, but in mixtures the diploid was slower to germinate than the tetraploid, (ii) as the density of sowing per pot was increased, the mean germination time (MGT) was increased, and (iii) the final germination of both verities decreased with increasing density.In a second experiment the same procedures were followed as before but seed of each variety was sown either as a pure stand or in a mixture of varying proportion as follows: 100:0, 75:25, 50:50, 25:75, 0:100.The results showed that (i) the diploid had the fastest MGT whilst the mixture values showed no significant variation, and (ii) the final germination percentage of the diploid decreased relative to its pure stand value as its proportion in mixtures decreased, whilst the tetraploid under the same circumstances increased relative to its pure stand value.It is suggested that differences such as those found could be explained by the presence of germination inhibitors in the seed coats of the two ryegrass varieties.

scholarly journals Breaking of dormancy in the narrow endemic Jasione supina Sieber subsp. supina (Campanulaceae) with small seeds that does not need the light to germinate

2020 ◽  
Vol 80 (1) ◽  
Author(s):  
Gürcan Güleryüz ◽  
Serap Kırmızı ◽  
Hülya Arslan ◽  
Elif Güleryüz
Keyword(s):  
Germination Percentage ◽  
Dormancy Breaking ◽  
Short Term ◽  
Germination Time ◽  
Physiological Dormancy ◽  
Moist Chilling ◽  
Dark Regime ◽  
Mean Germination Time ◽  
The Mean

The germination properties of Jasione supina Sieber subsp. supina (Campanulaceae), which is endemic to Mount Uludağ, Bursa, Turkey, were determined. In this study, we investigated the effects of GA3, the combination of hormone series and short-term moist chilling (1-month), and long-term moist chilling (4-month) on the germination percentage and mean germination time in relation to seed dormancy breaking. All treatment series were incubated under continuous dark (20 °C, 24 h) and light/dark (20/10 °C, 12/12 h) conditions. Seeds were collected from specimens widespread on alpine and subalpine grasslands and dwarf shrubs of Mount Uludağ (1800-1900 m a.s.l.). Depending on the concentration, GA3 and the combination of hormone and moist chilling treatments promoted seed germination in both dark and light/dark conditions. After 4-month-moist chilling treatment, seeds germinated 27% in light/dark and 80% in dark regime. Hormone and moist chilling treatments reduced the mean germination time. Our results showed that J. supina seeds have physiological dormancy, require prolonged times of moist chilling and preferentially complete germination in darkness.

scholarly journals Germination and vigor of seeds of Magonia pubescens A. St.-Hil. submitted to storage and pre-imbibition in water

2017 ◽  
Vol 39 (4) ◽  
pp. 344-352
Author(s):  
Cárita Rodrigues de Aquino Arantes ◽  
Carmen Lúcia Ferreira Fava ◽  
Elisangela Clarete Camili ◽  
Walcylene Lacerda Matos Pereira Scaramuzza
Keyword(s):  
Seed Size ◽  
Dry Mass ◽  
Germination Percentage ◽  
Shoot Height ◽  
Germination Time ◽  
Mean Germination Time ◽  
Number Of Leaves ◽  
Collar Diameter ◽  
The Mean ◽  
Storage Times

Abstract: Timbó (Magonia pubescens A. St.-Hil.) is a species with ornamental potential, which can be used in composition of gardens, squares and especially in streets landscaping. It is also suitable for planting in degraded areas of permanent preservation. This work aimed to verify the effect of seed size, storage and pre-imbibition time on seed germination and vigor. The test design was completely randomized, in a plot scheme subdivided in time. The main plots were seed size (large and small), packaging (0.5 mm-thick transparent polyethylene and kraft paper bag), and time of imbibition in water (0, 12 and 24 hours); and as subplots, it was considerate the storage times (0, 3, 6, 9 and 12 months). The tests were carried out in five replications of ten seeds, and the evaluated variables were: water content of the seeds, percentage of germination (% G), mean germination time (MGT), shoot height (cm), collar diameter (mm), number of leaves, and fresh and dry mass of the aerial part (g). The size of the seed did not influence the germination percentage, but large seeds formed more vigorous seedlings. The storage did not affect seeds germination, nor the vigor of the seedlings. Seed pre-imbibition did not influence the percentage of germination, but the mean germination time decreased, and more vigorous seedlings were formed. In order to obtain more vigorous Timbó seedlings, the best option is to use large seeds. They can be stored for up to 12 months without losing vigor and pre-soaked to accelerate the beginning of germination, thus forming a more homogeneous lot of seedlings.

An analysis of the differences in germination of seed lots of perennial ryegrass in response to artificial ageing

1989 ◽  
Vol 112 (3) ◽  
pp. 351-357 ◽  
Author(s):  
R. E. L. Naylor
Keyword(s):  
Normal Distribution ◽  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
Accelerated Ageing ◽  
Artificial Ageing ◽  
Germination Time ◽  
Before And After ◽  
Mean Germination Time ◽  
The Mean ◽  
Viable Seeds

SummaryStatistically sound methods for analysing the results of germination tests were used to quantify and assess differences between seed lots of perennial ryegrass (Lolium perenne L.) subjected to accelerated ageing. Ageing altered not only the proportion of seed not germinating but also the mean germination time and the synchrony of germination. Seed lots differed in these three parameters before and after ageing. The responses to ageing of mean germination time and synchrony were not regular and a simulation of trie possible effects of ageing on germination suggested this irregularity might be due to changes in the proportion of viable seeds and to a non-normal distribution of seed ages.

scholarly journals Geographical variation in germination traits of the salt-marsh cordgrass Spartina alterniflora in its invasive and native ranges

2020 ◽  
Author(s):  
Wen-Wen Liu ◽  
Yi-Hui Zhang
Keyword(s):  
Salt Marsh ◽  
Germination Percentage ◽  
Germination Index ◽  
Native Range ◽  
Invasive Range ◽  
Germination Time ◽  
Native Populations ◽  
Mean Germination Time ◽  
The Mean ◽  
Germination Traits

Abstract Aims Germination is the earliest life-history transition of a plant species. It determines the ecological breadth and geographic ranges of a species and has major effects on its invasion potential. The largest spread of the invasive salt-marsh cordgrass Spartina alterniflora in China, where it extends to latitudes lower than its native range in North America, provides an opportunity to examine germination trait variation across latitudes within and among its invasive and native ranges. Methods We studied seed germination traits of S. alterniflora using seeds collected from 10 locations across latitudes in its invasive range (China, 20°–40°N) and 16 locations across latitudes in its native range (USA, 27°–43°N) in growth chambers with 0 PSU sterilised distilled water. We further evaluated how climate and tide range in the original locations influenced germination traits. Important Findings Native populations showed higher (~10%) germination percentage and significantly higher (~20%) germination index than invasive populations did, but invasive populations germinated significantly earlier (~3 days) than native populations. Germination percentage and germination index increased with latitude in the invasive range but decreased with latitude in the native range. The mean germination time decreased with latitude in the invasive range and paralleled that in the native range. Germination percentage and germination index were negatively correlated with mean daily temperature (Tmean), mean daily maximum temperature (Tmax), and mean daily minimum temperature (Tmin), and inversely correlated with Tmean, Tmax, and Tmin in the native range. However, the mean germination time was positively correlated with Tmean, Tmax, and Tmean in both ranges. Our results demonstrate that invasive and native populations have evolved different latitudinal clines in germination percentage and index, but the mean germination time of the invasive population mirrored the latitudinal cline observed in the native range, suggesting that germination strategy across latitudes may change during invasion process.

scholarly journals Can Bulk and Nanosized Titanium Dioxide Particles Improve Seed Germination Features of Wheatgrass (Agropyron desertorum)

2013 ◽  
Vol 5 (3) ◽  
pp. 325-331 ◽  
Author(s):  
Reyhaneh AZIMI ◽  
Hassan FEIZI ◽  
Mohammad KHAJEH HOSSEINI
Keyword(s):  
Seed Germination ◽  
Germination Percentage ◽  
Germination Time ◽  
Positive Effects ◽  
Tio2 Particles ◽  
Nanosized Titanium Dioxide ◽  
Mean Germination Time ◽  
Germination Value ◽  
Improve Seed Germination ◽  
Nanosized Tio2

The goal of this study was to evaluate concentrations of nanosized TiO2 at 0, 5, 20, 40, 60 and 80 mg L-1 with bulk TiO2 for possible stimulatory effects on wheatgrass seed germination and early growth stage. After 14 days of seed incubation, germination percentage improved by 9% following exposure to 5 ppm nanosized TiO2 treatment comparing to control. Similar positive effects occurred in terms of germination value and mean daily germination. Application of bulk TiO2 particles in 80 ppm concentration greatly decreased the majority of studied traits. Therefore phytotoxicity effect observed on wheatgrass seedling by application of bulk TiO2 particles in 80 ppm concentration. Exposure of wheatgrass seeds to 5 ppm nanosized TiO2 and bulk and nanosized TiO2 at 60 ppm obtained the lowest mean germination time but higher concentrations did not improve mean germination time. In general, there was a positive response by wheatgrass seed to some concentrations of nanosized TiO2. Usage of nanoparicles in order to improve germination and establishment of range plant in adverse environments similar to rangeland could be possible.

scholarly journals Sensitivity of Seed Germination to Salt Stress in Teff [Eragrostis tef (Zucc.) Trotter]

2019 ◽  
Vol 76 (1) ◽  
pp. 91
Author(s):  
Panayiota PAPASTYLIANOU ◽  
Ilias TRAVLOS ◽  
Ioannis ROUSSIS ◽  
Dimitrios BILALIS
Keyword(s):  
Salt Stress ◽  
Agricultural Development ◽  
Animal Feed ◽  
Moisture Stress ◽  
Germination Percentage ◽  
Limiting Factors ◽  
Eragrostis Tef ◽  
Germination Time ◽  
Randomized Design ◽  
Mean Germination Time

Teff is an annual grass originated in Ethiopia, grown for both human food and animal feed. Salinity and moisture stress are the main limiting factors of agricultural development on arid and semi-arid regions. The aim of this study was to investigate the effect of salinity due to NaCl on germination of teff. A set of experiments was conducted under a completely randomized design with four replications of 200 seeds at two different suboptimal germination temperatures (15 and 25 °C) in the dark for 10 days. In order to create salt stress conditions during the germination process, seven solutions were used (0 as control, 80, 160, 240 and 320, 400 and 480 mM NaCl). The germination performance was evaluated by final germination percentage and mean germination time. The presence of NaCl reduced germination, especially above 240 mM for 15 °C and 400 mM for 25 °C. The mean germination time increased with higher NaCl levels.

scholarly journals Evaluation of Seed Quality Attributes of Sorghum Germplasm Accessions from Eastern, Coastal and Nyanza Regions, Kenya

2020 ◽  
Vol 9 (3) ◽  
pp. 9
Author(s):  
C. W. Muui ◽  
R. M. Muasya ◽  
S. Nguluu ◽  
A. Kambura
Keyword(s):  
Food Security ◽  
Seed Quality ◽  
Germination Percentage ◽  
Seed Vigour ◽  
Subsistence Farmers ◽  
Germination Time ◽  
Vigour Index ◽  
Mean Germination Time ◽  
Handling Practices ◽  
Germplasm Accessions

Sorghum (Sorghum bicolor L.) is an important cereal crop in Kenya. Despite the crops importance, the yields attained by farmers in Eastern, Coastal and Nyanza regions of Kenya remain low. Access to good quality seeds of sorghum is one of the constraints facing the subsistence farmers. Good quality seed is important for increasing yield to attain food security. The aim of this study was to evaluate quality attributes of the seed used by farmers. A total of 108 germplasm accessions were obtained from 76 farmers. The seeds were tested for time and percentage of germination, seed vigour index, shoot and root dry weight. Data collected was subjected to analysis of variance. Means were separated using Fisher’s Least Significance Difference test at p ≤ 0.05. Seed samples of 26 accessions attained germination percentage below stipulated standards by Seeds and Plant Varieties Act CAP 326. Majority of seeds showed longer mean germination time with only nine accessions germinating in less than ten days. Seed vigour index was relatively high in most of the accessions, while biomass accumulation varied from high to very low among accessions. Though most of the seeds attained a high germination percentage, about 92% of seeds showed longer mean germination time. The environmental conditions in the fields, pre and post harvest handling practices impact on the seed quality hence the wide variability in germination percentage, germination time, seed vigour index and dry matter accumulation. Therefore the need to improve quality of seeds used by subsistence farmers by providing extension services on best pre and post harvest handling practices. Increasing production of sorghum in these regions will contribute significantly towards realizing food security. Further analysis could be carried out on genetic and sanitary quality aspects of the seeds planted by farmers in Eastern, Nyanza and Coastal regions.

scholarly journals Pre-germinative treatments and seed storage of Psidium cattleyanum Sabine morphotypes

2020 ◽  
Vol 16 (4) ◽  
pp. 102-109
Author(s):  
Haron Victor Ferreira Camargo ◽  
Letícia Siqueira Walter ◽  
Mônica Moreno Gabira ◽  
Dagma Kratz
Keyword(s):  
Storage Period ◽  
Seed Storage ◽  
Germination Percentage ◽  
Transparent Plastic ◽  
Germination Time ◽  
Hand Control ◽  
Germination Speed ◽  
Mean Germination Time ◽  
Cold Chamber

This study aimed to evaluate the germination behavior of two morphotypes of P. cattleyanumsubmitted to storage and pre-germinative treatments. The experiment was designed in a factorial scheme 2 x 3 x 3 (morphotypes x storage periods x pre-germinative treatments) completely randomized, using for each treatment 5 replicates with 30 seeds. The seeds were stored in semipermeable packages in a cold chamber at 5 ± 2 °C, for 14, 45,and 90 days. After each storage period, the seeds were submitted to treatments to overcome dormancy: immersion in water at 80 °C,kept in imbibition for 24 and 48 hand control, without any treatment. The seeds were arranged under moistened substrate in transparent plastic boxes and allocated in a germination chamber at 25 °C and photoperiod of 8 h for evaluation of germination percentage (G), germination speed index (GSI)and mean germination time (MGT). The red morphotype seeds showed higher germination percentages than the yellow morphotype and did not have a reduction in these values after 90 days of storage. MGT for yellow morphotype was lower in all pre-germinativetreatments. The GSI had better results at 45 days in the control treatments and 24 h in immersion in water and 90 days for the three pre-germinative treatments. The red morphotype does not require pre-germinative treatments, while the yellow morphotype presents better germination when the seeds are stored for 45 days and immersed in water at 80 °C for 48 h.

scholarly journals Sensitivity of Seed Germination to Temperature and Light in Helichrysum amorginum

2020 ◽  
Vol 77 (1) ◽  
pp. 7
Author(s):  
Sofia ARGYRIOU ◽  
Panayiota PAPASTYLIANOU ◽  
George STAVROPOULOS ◽  
Angeliki KOUSTA ◽  
Ioanna KAKABOUKI ◽  
...  
Keyword(s):  
Seed Germination ◽  
Seedling Survival ◽  
Germination Percentage ◽  
Effect Of Temperature ◽  
Germination Time ◽  
Randomized Design ◽  
Perennial Shrub ◽  
Mean Germination Time ◽  
Lower Temperature ◽  
Seed Propagation

Helichrysum amorginum is a perennial shrub, endemic on the Greek island of Amorgos and used for medicinal, cosmetic and ornamental purposes. Information concerning germination behavior and seedling survival is considered essential for the establishment and cultivation of wild species. The objective of this study was to investigate the effect of temperature and light on germination of Helichrysum amorginum seeds. A set of experiments was conducted under completely randomized design with four replications of 200 seeds at three different suboptimal germination temperatures (15, 20 and 25°C) in light and dark conditions for 10 days. Seed material was collected from two different fields of the island (Aegiali and Katapola). The germination performance was evaluated by final germination percentage and mean germination time. The effect of temperature on seed germination percentage and mean germination time was significant in all cases. The presence of light enhanced germination, especially at the optimum temperature of 20°C. In most cases the mean germination time increased at the lower temperature of 15°C. Seeds from Aegiali exhibited higher germination ability than the seed lot from Katapola. Knowledge of seed germination behaviour is of major importance in order to establish effective protocols for seed propagation in Helichrysum amorginum.

scholarly journals A, The EXPLORING THE ALLELOPATHIC AND HERMETIC EFFECT OF KHATAMI (Altheae officinalis) ON EMERGENCE AND SEEDLING GROWTH OF RADISH (Raphanus sativus)

2021 ◽  
Vol 27 (3) ◽  
pp. 321-330
Author(s):  
Bilal Ahmad Khan
Keyword(s):  
Aqueous Extract ◽  
Seedling Growth ◽  
Root Length ◽  
Raphanus Sativus ◽  
Germination Percentage ◽  
Shoot Length ◽  
Fresh Weight ◽  
Germination Time ◽  
Shoot Fresh Weight ◽  
Mean Germination Time

Abstract Crop plants release biochemicals into surrounding environment that help in obtaining maximum yield of crop by acting bioherbicide at high concentration and plant growth hormone at low concentration. Therefore, this study was planned at Department of Agronomy in Weed Science Laboratory, University of Agriculture Faisalabad during Winter 2018 to evaluate the hermetic effects of Althaea officinalis L. (khatami) on vegetable crop Radish (Raphanus sativus) The experiments were laid out under completely randomized design (CRD) having three replications. The aqueous extracts of A. officinalis L. were used on radish different concentrations (2.5%, 5%, 10%, 20%, 40% and 80%). Data regarding seed germination and seedling growth (shoot length, root length, shoot fresh weight, root dry weigh) of radish were recorded using standard procedures. Results Reveals that the aqueous extract of A. officinalis at higher concentration (80%) act as bioherbicide and produced inhibitory effects on R. sativus result in Maximum time to 50% germination (4.68 days) and mean germination time (9.05 days) while minimum germination index (3.60), germination percentage (85.00%), shoot length (42.4 cm), root length (25.90 cm), shoot fresh weight (53.30 g) and root fresh weight (13.30 g). While at lower concentration (10%) it shows hermetic effect and produce maximum germination percentage (100.00%), shoot length (58.2 cm), root length (52.0 cm), shoot fresh weight (90.00g), root fresh weight (26.30 g) minimum time to complete 50% germination (3.36 days), germination index (6.00%) and mean germination time (5.73 days) growth. In A. officinalis among different phenolic compound minimum Syringic acid (0.60%) and maximum Quercetion (12.3%) compound was found. Therefore, it was concluded from this study that aqueous extract of officinalis can be used as growth promoter at lower concentration while at higher concentration for environmentally friendly control of weeds.

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