SEED GERMINATION OF AMERICAN BASSWOOD IN RELATION TO SEED MATURITY

1982 ◽  
Vol 62 (3) ◽  
pp. 709-713 ◽  
Author(s):  
D. E. VANSTONE ◽  
W. G. RONALD
Keyword(s):  
Seed Germination ◽  
Moisture Content ◽  
Light Microscopy ◽  
Late Summer ◽  
Differential Staining ◽  
Cell Orientation ◽  
Seed Maturity ◽  
Advanced Stages ◽  
High Degree ◽  
Excised Embryos

Seed germination of American basswood collected and sown at weekly intervals during late summer 1977 increased until the 9 Sept. collection at which germination was 52%; thereafter, germination decreased. The color of the pericarp and the moisture content of the seed proved reliable indices of maturity in relation to germination. All pericarps turned greyish-brown by 9 Sept. and moisture content of the seed decreased to 16%. Germination of excised embryos occurred without delay at all stages of seed maturity. Examination of the structure of the testa by means of differential staining and light microscopy showed a high degree of cell orientation, compaction and lignification at the advanced stages of maturity.

RAPID DETERMINATION OF SEED GERMINATION POTENTIAL TO MEASURE QUALITY LOSS IN STORED WHEAT

1982 ◽  
Vol 62 (4) ◽  
pp. 1045-1048 ◽  
Author(s):  
N. D. G. WHITE ◽  
R. N. SINHA ◽  
W. E. MUIR
Keyword(s):  
Seed Germination ◽  
Moisture Content ◽  
Rapid Method ◽  
Rapid Determination ◽  
Quality Loss ◽  
Wheat Seed ◽  
Stored Wheat ◽  
Germination Potential

A rapid method of determining wheat seed germination after 1 day (G1) of incubation was found. Germination of wheat seed stored at [Formula: see text] moisture content is estimated by adding 12% to G1; at <17% moisture content germination is not consistently predicted by G1.

scholarly journals Sexual maturation in Atlantic salmon male parr may be triggered both in early spring and late summer under standard farming conditions

2021 ◽  
Author(s):  
Elia Ciani ◽  
Kristine von Krogh ◽  
Rasoul Nourizadeh-Lillabadi ◽  
Ian Mayer ◽  
Romain Fontaine ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Sexual Maturation ◽  
Late Summer ◽  
Early Spring ◽  
Plasma Testosterone ◽  
Farmed Salmon ◽  
Early Maturing ◽  
Advanced Stages ◽  
One Year ◽  
Immature Fish

AbstractMale Atlantic salmon (Salmo salar) display different sexual strategies, maturing either as parr during the freshwater phase (as sneaky spawners), or as post smolts following one or several years at sea. First sexual maturation (puberty) occurs at different times depending on environmental and genetic factors. To improve our knowledge on the timing (age and season) of first sexual maturation in Atlantic salmon male parr, we investigated pubertal activation in second generation farmed salmon from the Norwegian river Figgjo, reared under natural conditions of photoperiod and water temperature. Histological analysis, in combination with morphometric measurements, plasma androgen levels and pituitary gonadotropin gene expression analysis revealed that, as previously reported, some male parr initiated early sexual maturation in spring at one year of age. Interestingly, some male parr were observed to initiate sexual maturation already in autumn, six months after hatching (under-yearlings), much earlier than reported in previous studies. One-year old maturing males showed a low induction in gonadotropin levels, while under-yearling maturing males displayed a significant increase in fshb transcripts as compared to immature fish. Plasma testosterone, detectable also in immature males, increased constantly during testes development, while 11-ketotestosterone, undetectable in immature and early maturing males, increased during more advanced stages of maturation. A mild feminization of the testes (ovotestes) was detected in a subset of samples. This study brings new knowledge on the little investigated field of sexually maturing under-yearlings in Atlantic salmon. This is also the first study comparing the physiology of under-yearling vs one-year old maturing male parr, thus bringing new insights to the remarkable plasticity of Atlantic salmon puberty.

Seed Storage and Germination Performance in Knema attenuata - an Endemic Medicinal Tree of Western Ghats, India

2021 ◽  
Vol 27 (3) ◽  
pp. 162-166
Author(s):  
Abdul Azeez Hussain ◽  
◽  
Ramachandra Kurup Rajvikraman ◽  
Keyword(s):  
Seed Germination ◽  
Relative Humidity ◽  
Moisture Content ◽  
Seed Bank ◽  
Tree Species ◽  
Western Ghats ◽  
Climatic Condition ◽  
Seed Storage ◽  
Medicinal Tree

Detailed study on seed storage and germination trailed in Knema attenuata (Wall. ex Hook. f. & Thomson) Warb.– the IUCN Red Listed ‘least concern’ medicinal tree species revealed that seeds were of recalcitrant nature. Viability of the seeds could be maintained for a longer period of up to 6 months with 47% Moisture content (mc) when kept in closed polycarbonate bottles at seed bank condition [20±20C Temp. and 40% Relative Humidity (RH)]. The 55% seed germination under normal climatic condition could be enhanced to a much higher percentage (75±5) inside the mist house chamber (34±30C Temp. and 70-80% RH).

Seed storage behaviour and seed germination in African and Malagasy baobabs (Adansonia species)

2006 ◽  
Vol 16 (1) ◽  
pp. 83-88 ◽  
Author(s):  
Juvet Razanameharizaka ◽  
Michel Grouzis ◽  
Didier Ravelomanana ◽  
Pascal Danthu
Keyword(s):  
Seed Germination ◽  
Moisture Content ◽  
Seed Storage ◽  
The Other ◽  
Arid Zones ◽  
Physical Dormancy ◽  
Interspecific Differences ◽  
Wet Forests

The Adansonia (baobab) genus comprises seven species in Africa, six of which are endemic to Madagascar. Depending on the species, baobabs develop in widely varying ecosystems, including arid zones and savannahs, as well as dry and wet forests. Seeds from all species exhibited orthodox behaviour, tolerating dehydration to a moisture content of around 5%. There was no physical dormancy in the two species belonging to the Brevitubae section, A. grandidieri and A. suarezensis. Their seeds germinated without any prior scarification. The five other species, belonging to Adansonia and Longitubae section, have seeds with water-impermeable coats. In the case of A. digitata and A. za, the proportion of water-impermeable seeds was around two-thirds, whereas with A. rubrostipa, A. madagascariensis and A. perrieri, the proportion was >90%. Treatments allowing for the removal of physical dormancy needed to be markedly more severe with A. madagascariensis than with the other species. None the less, it seems impossible to link these characteristics and the interspecific differences to a strategy for adaptation by these species to their environment.

Factors Affecting Seed Germination and Seedling Emergence of Asia Minor Bluegrass (Polypogon fugax)

Weed Science ◽  
2015 ◽  
Vol 63 (2) ◽  
pp. 440-447 ◽  
Author(s):  
Xian Wu ◽  
Jun Li ◽  
Hongle Xu ◽  
Liyao Dong
Keyword(s):  
Seed Germination ◽  
Seedling Emergence ◽  
Late Summer ◽  
Asia Minor ◽  
Burial Depth ◽  
Optimum Temperature ◽  
Large Area ◽  
Factors Affecting ◽  
Temperature Regimes ◽  
Grass Weed

Little published information is available related to seed germination and seedling establishment of Asia Minor bluegrass, a problematic grass weed in some regions of China. The objective of this study was to examine the effects of different environmental factors on Asia Minor bluegrass seed germination. The optimum temperature for germination was around 10 to 20 C, and more than 90% of seeds germinated under 20/10 and 25/15 C temperature regimes. Also, light and pH did not appear to have any effect on seed germination. Asia Minor bluegrass was sensitive to osmotic stress, but tolerant of NaCl. No seedlings emerged when seeds were buried 4 cm deep. The result suggested that Asia Minor bluegrass has the potential to spread into a large area in China. To prevent its spreading, measures such as soil cultivation can be used to limit seed germination from increased burial depth and/or nonselective herbicides can be applied to kill early-germinating weed seedlings in late summer.

scholarly journals Germination of Psidium friedrichsthalianum (O. Berg) Nied. seeds under different temperature and storage conditions

2018 ◽  
Vol 40 (3) ◽  
pp. 246-252 ◽  
Author(s):  
Daniel Felipe de Oliveira Gentil ◽  
Sidney Alberto do Nascimento Ferreira ◽  
Elizabeth Rodrigues Rebouças
Keyword(s):  
Seed Germination ◽  
Moisture Content ◽  
Storage Conditions ◽  
Germination Speed ◽  
Meloidogyne Spp ◽  
And Storage

Abstract: Psidium friedrichsthalianum is a species whose fruit can be used to make juices, jellies/jams and sweets, and its seedlings serve as rootstocks with resistance to Meloidogyne spp. The aim of this study was to evaluate the performance of seeds of this species at different germination temperatures, and to verify the effects of different moisture levels on their storage in two experiments. In the first, six germination temperatures (15, 20, 25, 30, 35, and 40 ºC) were evaluated, and in the second, seeds with different moisture levels (15.4, 9.8, 9.0, 8.4, and 8.2%) were stored in sealed containers at 20 °C for 0, 1, 3, 6, 9, and 12 months. Seed germination was favored by temperatures of 20 ºC and 25 ºC, reaching 93% and 87%, respectively, along with the highest germination speed indexes (2.582% day1 and 2.568% day-1) and shortest germination times (37.9 and 36.9 days). Temperatures of 30 °C and 35 °C maintained the seeds quiescent, while 40 °C was lethal. In storage, the seeds tolerated desiccation to 8.2% moisture content and could be stored in sealed containers at 20 ºC for 12 months, with germination higher than 70%.

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

1993 ◽  
Vol 23 (7) ◽  
pp. 1306-1313 ◽  
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.

Breeding

1935 ◽  
Vol 8 (4) ◽  
pp. 54-80
Keyword(s):  
Low Temperature ◽  
Moisture Content ◽  
Early Stage ◽  
Control Group ◽  
List Type ◽  
Type Number ◽  
Depressing Effect ◽  
Internal Organs ◽  
Completely Regular ◽  
High Degree

Growth of Chicken-Embryos. Das Wachstum des Hühnerembryos in Abhängigkeit von verschiedenen Temperaturen und Feuchtigkeitsgraden im Brutapparat. N. M. Schkljar. Archiv für Geflügelkunde, 1935, No. 5.Summary:1.A completely regular and strong growth of the hen embryos is obtained with a temperature of 38.4° C. (101.1° F.) and 64% moisture.2.A temperature of 39.9° C. (103.82° F.) and 62% moisture have a somewhat depressing effect on the developement of the embryos during the first six and last two days of the incubation, an increase in growth taking place on the 16th days.3.A high degree of moisture of 77% and a temperature of 38.3 ° C. (100.9° F.) prevent growth up to the 18th day, a decisive increase taking place after this date.4.With a low temperature of 37° C. (98.66° F.) and a moisture content of 63%, the developement of embryos remains noticeably backward, specially during the first few days. Under such conditions, as early as after the sixth day, growth in relation to the control group is delayed by two days.5.Between the increase in weigth and the developement of embryos, there exists, in an early stage, an inverted ratio of dependance.6.The rate of growth of the internal organs is not a process working within itself, but subject to the general conformity to law.7.The growth of the embryo is not the result of an uninterruped developement, but consists of a sequence of increases and depressions.

scholarly journals Multi-channel ground-penetrating radar to explore spatial variations in thaw depth and moisture content in the active layer of a permafrost site

2010 ◽  
Vol 4 (3) ◽  
pp. 269-283 ◽  
Author(s):  
U. Wollschläger ◽  
H. Gerhards ◽  
Q. Yu ◽  
K. Roth
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Active Layer ◽  
Ground Penetrating Radar ◽  
Soil Moisture Content ◽  
Late Summer ◽  
Bare Soil ◽  
Thaw Depth ◽  
Ground Penetrating ◽  
Gravel Road

Abstract. Multi-channel ground-penetrating radar (GPR) was applied at a permafrost site on the Tibetan Plateau to investigate the influence of surface properties and soil texture on the late-summer thaw depth and average soil moisture content of the active layer. Measurements were conducted on an approximately 85 × 60 m2 sized area with surface and soil textural properties that ranged from medium to coarse textured bare soil to finer textured, sparsely vegetated areas covered with fine, wind blown sand, and it included the bed of a gravel road. The survey allowed a clear differentiation of the various units. It showed (i) a shallow thaw depth and low average soil moisture content below the sand-covered, vegetated area, (ii) an intermediate thaw depth and high average soil moisture content along the gravel road, and (iii) an intermediate to deep thaw depth and low to intermediate average soil moisture content in the bare soil terrain. From our measurements, we found hypotheses for the permafrost processes at this site leading to the observed late-summer thaw depth and soil moisture conditions. The study clearly indicates the complicated interactions between surface and subsurface state variables and processes in this environment. Multi-channel GPR is an operational technology to efficiently study such a system at scales varying from a few meters to a few kilometers.

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