Fruit and seed polymorphism and its relation to seedling growth in the genus Cakile

1989 ◽  
Vol 67 (9) ◽  
pp. 2743-2750 ◽  
Author(s):  
M. A. Maun ◽  
A. M. Payne
Keyword(s):  
Growth Rate ◽  
Seed Mass ◽  
Germination Percentage ◽  
Dispersal Ability ◽  
Relative Growth ◽  
Frequency Distributions ◽  
Cakile Maritima ◽  
Cakile Edentula ◽  
Germination Behaviour ◽  
Better Than

To ascertain the adaptive significance of dimorphism under unpredictable environments, the dimorphic fruit segments of Cakile edentula var. lacustris, Cakile edentula var. edentula, and Cakile maritima were tested for differences in size of propagules, dispersal ability, germination behaviour, and growth rate. The upper and lower fruit segments differed in some attributes but not in others. For example, the fruits, seeds, and shells of upper segments were significantly heavier than those of lower segments. However, the frequency distributions of mean mass per seed, shell, and fruit indicated a considerable zone of overlap beneath the histograms of upper and lower fruit segments. Under still conditions in a greenhouse, no differences were found in the floating ability of upper and lower fruit segments of C. edentula var. lacustris and C. maritima. Of the three taxa, C. maritima fruits had the highest shell to seed mass ratio and floated for the longest period of time. Morphological seed dimorphism was linked with a physiological seed dimorphism. The lower fruit segments of C. edentula var. lacustris germinated better than the upper fruit segments over a wider range of temperatures. Light did not alter the final germination percentage of upper or lower fruit segments but inhibited the rate of germination. The relative growth rate decreased in all three taxa with an increase in the age of a seedling, irrespective of its seed weight.

scholarly journals Seed mass effects on germination and growth of diverse European Scots pine populations

1994 ◽  
Vol 24 (2) ◽  
pp. 306-320 ◽  
Author(s):  
P.B. Reich ◽  
J. Oleksyn ◽  
M.G. Tjoelker
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Scots Pine ◽  
Field Experiments ◽  
Seed Mass ◽  
Growing Season ◽  
Turkish Population ◽  
Dry Mass ◽  
Relative Growth ◽  
Mass Effects

Seedlings of 24 European Scots pine (Pinussylvestris L.) populations were grown in controlled environment chambers under simulated photoperiodic conditions of 50 and 60°N latitude to evaluate the effect of seed mass on germination and seedling growth characteristics. Seeds of each population were classified into 1-mg mass classes, and the four classes per population with the highest frequencies were used. Photoperiod had minimal influence on seed mass effects. Overall, seed mass was positively related to the number of cotyledons and hypocotyl height. Populations differed significantly in seed mass effect on biomass. In northern populations (55–61°N), dry mass at the end of the first growing season was little affected by seed mass. However, dry mass in 9 of 15 central populations (54–48°N) and all southern (<45°N) populations correlated positively with seed mass. Relative growth rate was not related to seed mass within or across populations, and thus early growth is largely determined by seed mass. Relative growth rate also did not differ among populations, except for a geographically isolated Turkish population with the highest seed mass and lowest relative growth rate. After one growing season, height was positively correlated (r2 > 0.6) with seed mass in 15 populations. To check the duration of seed mass effects, height growth of 1- to 7-year-old field experiments established with the same seed lots were compared. Seed mass effects on height were strongest for 1-year-old seedlings and declined or disappeared by the age of 5–7 years among central and southern populations, but remained stable over that time in northern populations.

scholarly journals Features of body weight growth in meat breeds heifers

2016 ◽  
Vol 18 (2) ◽  
Author(s):  
R. S. Oseredchuk ◽  
N. P. Babik ◽  
V. V. Fedorovych ◽  
E. I. Fedorovych ◽  
V. R. Dutka
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Weight Changes ◽  
Body Weight Changes ◽  
Relative Growth ◽  
Weight Growth ◽  
Rate Of Increase ◽  
The Difference ◽  
Tension Increase ◽  
Better Than

The data on the dynamics of body weight changes, absolute and average daily gains, frequency rate of increase in body weight, relative growth rate and intensity of body weight growth of Limousine and Volyn Meat breeds heifers. Both studied breeds characterized by different body weight at different age periods. Newborn Limousine breed heifers are weighed 2,7 kg more (P < 0.05) than Volyn Meat breed heifers; at 3 months age the difference was 8.5 kg (P < 0.05) at 6 months – 14.6 kg, at 9 month – 20.8 kg (P < 0.05), at 12 months – 25,6 kg (P < 0.05), at 15–months – 31.9 (P<0,05), and at 18 months – 23.5 kg. Total and average daily gains in animals of both breeds were the highest for a period of 3 to 6 months of age. In the period from birth to 15 months of age preference for average daily gains were in Limousine, however, the difference was statistically significant only for the period of 0 – 3 months and amounted to 63,9 g (P < 0,05). From 15 to 18 months of age Limousine slightly conceded to Volyn Meat breeds on this parameter. In animals of both breeds magnification of body weight increased with age, but over the entire period (from birth to 18 months) this parameter in Volyn Meat heifers was 0.6 times better than Limousine heifers. The coefficients of relative intensity and tension increase of body weight in animals of both breeds were highest in the period from birth to 3 months of age. With age, these indicators declined. Mainly, the advantage was in Volyn meat breed heifers, but the difference was not statistically significant.

Phosphorus efficiency in pasture species. I. Measures based on total dry weight and P content

1988 ◽  
Vol 39 (5) ◽  
pp. 807 ◽  
Author(s):  
RH Chisholm ◽  
GJ Blair
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
White Clover ◽  
Phosphorus Deficiency ◽  
Dry Weight ◽  
Phosphorus Efficiency ◽  
P Efficiency ◽  
Relative Growth ◽  
Internal Efficiency ◽  
Better Than

Two solution culture experiments were conducted to compare the efficiency of phosphorus use and indicies for measuring it in a tropical and a temperate pasture legume. The species chosen were Stylosanthes hamata cv. 'Verano' (Caribbean stylo) and Trifolium repens cv. 'Ladino' (white clover).The first experiment used two solution P concentrations (2, 16 8M) to investigate differences between species in the rate and extent of P uptake. The second experiment used five solution P concentrations (1, 2, 4, 8, 16 8M ) to evaluate differences between species in internal efficiency of P utilization.There was no difference between white clover and stylo in the capacity to remove P from the same solution P concentrations. However, in both species the extent of depletion of solutions by plants grown at high P was not as great as that plants grown at low P. The ranking of species in terms of their internal efficiency or relative growth rate changed with time and P concentrations.Growth of white clover was better than stylo where there was a moderate deficiency of phosphorus. Alternatively, growth of stylo was better than white clover where phosphorus deficiency was more severe. The relative growth rate of stylo at low (2 8M ) P was maintained above 8% per day after prolonged P stress, whilst in white clover at the same P concentration RGR fell to less than 2% per day.Internal P efficiency or the amount of dry matter accumulated per unit P accumulated per unit time showed that white clover was more P efficient than stylo in the early stages of growth.

scholarly journals Pros and cons of using a standard protocol to test germination of alpine species

Plant Ecology ◽  
2020 ◽  
Vol 221 (11) ◽  
pp. 1045-1067
Author(s):  
Vera Margreiter ◽  
Konrad Pagitz ◽  
Christian Berg ◽  
Patrick Schwager ◽  
Brigitta Erschbamer
Keyword(s):  
Seed Mass ◽  
Eastern Alps ◽  
Germination Percentage ◽  
Standard Protocol ◽  
Csr Strategies ◽  
Alpine Regions ◽  
Alpine Species ◽  
Germination Behaviour ◽  
The One ◽  
Species Rarity

Abstract Storing seeds in seed banks is an effective way to preserve plant diversity and conserve species. An essential step towards a valuable conservation is the validation of germination. This study presents a germination screening of seeds from 255 species of the European Eastern Alps, which were to be stored at the Millennium Seed Bank (Kew, UK). The final germination percentage (FGP) was determined using a standard protocol in the laboratory. Species were classified according to species rarity, plant community, occurrence at elevation belts, bedrock types, as well as CSR strategies, and further, seed mass was examined. We could not find statistically significant differences of FGP within these classes, but 74.9% of all tested species germinated using the standard protocol, and half of them had FGP ≥ 20.1–100%. A treatment with gibberellic acid enhanced the germination in half of the species to which this treatment was applied. Common families in alpine regions, i.e. Asteraceae, Poaceae and Saxifragaceae were highlighted in terms of their germination behaviour. The results provide an evaluation of the application of standard protocols to a broad Alpine species pool on the one hand, and on the other hand, provide ecological insights of the species tested. Germination is not only one of the most important events of the reproductive cycle of plants but could also be a key feature in species' responses to changing environmental conditions.

scholarly journals Effect of seed mass on germination and growth in three dominant species in southern Brazilian coastal dunes

2002 ◽  
Vol 62 (3) ◽  
pp. 427-435 ◽  
Author(s):  
C. V. CORDAZZO
Keyword(s):  
Growth Rate ◽  
Seed Germination ◽  
Relative Growth Rate ◽  
Seed Mass ◽  
Coastal Dunes ◽  
Biological Factor ◽  
Relative Growth ◽  
Mass Size ◽  
Germination And Growth ◽  
Brazilian Populations

The effect of seed mass on germination and growth was tested in fresh-seeds of Blutaparon portulacoides, Panicum racemosum, and Spartina ciliata, selected at random in southern Brazilian populations. The seed mass varied within a population of the three species. Both B. portulacoides and P. racemosum showed normal frequency distribution of seed mass, while S. ciliata did not. Significant differences were observed in seed germination between large and small seeds of all species. In all species the capacity of seedling elongation was greater in seedlings of large seeds than those of small ones. Relative growth rate of seedlings of P. racemosum and S. ciliata decreased with time in all seed mass size-classes. On the other hand, the relative growth rate of B. portulacoides seedlings increased during the first 40 days. Seed mass is an important biological factor, affecting seed germination, seedling elongation, and growth of these species, and favoring large seeds, specially in areas of active sand accretion like coastal dunes.

Trade-offs between growth and survival of non-pioneer light-demanding tree seedlings in tropical forest of Hainan Island, China

2011 ◽  
Vol 27 (6) ◽  
pp. 611-620 ◽  
Author(s):  
Wenjie Yang ◽  
Fude Liu ◽  
Lingyan Zhou ◽  
Shiting Zhang ◽  
Shuqing An
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Tree Species ◽  
Seed Mass ◽  
High Light ◽  
Tree Seedlings ◽  
Low Light ◽  
Relative Growth ◽  
Growth And Survival ◽  
Light Levels

Abstract:We performed a pot experiment in which 540 seedlings of nine non-pioneer light-demanding tree species were grown for 12 months in shade houses at three light levels, 46% daylight, 13% daylight and 2% daylight, to examine the mechanisms contributing to the coexistence of seedlings of non-pioneer light-demanding tree species in secondary successional tropical rain forest in Hainan, China. Growth and survival of tree seedlings were compared at different light levels, and the morphological and physiological correlates of high-light seedling growth and low-light survival across species were determined. For all species, mortality was very low in the 46% daylight and 13% daylight treatment but increased significantly in the 2% daylight treatment. Seedling survival in 2% daylight treatment was positively related to seed mass. Trade-off between high-light growth and low-light survival was more evident in the relationship with 2% daylight treatment as compared with 13% daylight treatment. Relative growth rate in the 2% daylight treatment was not significantly related to relative growth rate in the 13% daylight or 46% daylight treatment; although a slight negative correlation was apparent. Interspecific variation in RGRm was only closely correlated with net assimilation rate (NAR). The results provide some support for the niche-partitioning hypothesis.

Effects of achene dimorphism on dormancy and progeny traits in the two ephemerals Hedypnois cretica and Crepis aspera (Asteraceae)

2003 ◽  
Vol 81 (6) ◽  
pp. 550-559 ◽  
Author(s):  
Ali El-Keblawy
Keyword(s):  
Storage Temperature ◽  
Storage Period ◽  
Germination Percentage ◽  
Adaptive Significance ◽  
Dispersal Ability ◽  
Coastal Desert ◽  
Selective Forces ◽  
Germination Behaviour ◽  
Size And Morphology ◽  
The Relationship

Hedypnois cretica (L.) Dum.-Cours. and Crepis aspera L. are ephemeral composites native to the Mediterranean coastal desert of Sinai, Egypt, with marked achene dimorphism. This study examined the relationship between achene morphology and both some progeny traits and germination behaviour in terms of final germination percentage and germination speed. The effects of length of achene storage and temperature of storage on germination behaviour were particularly examined. Fresh harvested seeds showed little germination. After 6 months of storage, central achenes attained higher germination percentages in the two species and germinated faster in C. aspera than the peripheral achenes. The dormancy loss was faster in achenes of H. cretica than in those of C. aspera. Greater germination dimorphism was associated with greater dimorphism in size and morphology and consequently in the dispersal ability of the two morphs of C. aspera than in H. cretica. Warm storage significantly enhanced the germination level and speed of the heavier peripheral achenes compared with those of the central achenes of both species, so this was dependent on storage period. Plants produced by peripheral achenes had a significantly greater size than those from central achenes. This difference was more pronounced in H. cretica and persisted until 70 days postemergence but disappeared after 40 days in C. aspera. Results are discussed in light of possible adaptive significance and selective forces, such as the differential dispersal, dormancy, and growth of the two morphs, that maintain the dimorphism in the unpredictable heterogeneous deserts.Key words: achene dimorphism, Asteraceae, dormancy, germination, storage temperature.

Hydrocarbon Tolerance Correlates with Seed Mass and Relative Growth Rate

2004 ◽  
Vol 8 (3-4) ◽  
pp. 185-199 ◽  
Author(s):  
Diana Bizecki Robson ◽  
James J. Germida ◽  
Richard E. Farrell ◽  
Diane J. Knight
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Seed Mass ◽  
Relative Growth

scholarly journals PENGARUH EKSTRAKSI BIJI DAN KOMBINASI MEDIA TANAM TERHADAP PENYEMAIAN LABAN (Vitex pinnata L. Kuntze)

2019 ◽  
Vol 12 (1) ◽  
pp. 89-95
Author(s):  
Hartina Hartina ◽  
Ratna Kusuma ◽  
Dwi Susanto
Keyword(s):  
Growth Rate ◽  
Plant Height ◽  
Relative Growth Rate ◽  
Dry Weight ◽  
Germination Percentage ◽  
Leaf Number ◽  
Relative Growth ◽  
Seed Growth ◽  
Seed Extraction ◽  
Wet Weight

AbstrakPenyemaian laban dengan menggunakan metode ekstraksi biji belum banyak dilakukan dan perlu penambahan bahan pembenah tanah untuk meningkatkan pertumbuhan semai. Penelitian ini bertujuan untuk mengetahui pengaruh ekstraksi biji dan kombinasi media tanam terhadap penyemaian laban (Vitex pinnata L. Kuntze). Penelitian ini menggunakan rancangan acak lengkap dengan 2 faktor perlakuan yaitu ekstraksi biji (A0= ekstraksi basah dan A1= ekstraksi kering) dan kombinasi media tanam (M0= Tanah, M1= tanah + pasir, M2= tanah + kompos, M3= tanah + cocopeat), masing-masing diulang sebanyak 3 kali. Data yang diperoleh dianalisis dengan menggunakan uji varian (ANOVA) dengan taraf kepercayaan 95%, uji lanjut menggunakan uji Duncan pada taraf kepercayaan 95%. Hasil penelitian menunjukkan pada perlakuan ekstraksi biji kering dapat meningkatkan rata-rata persentase berkecambah sebesar 65,83% dan kecepatan tumbuh biji sebesar 3,25%, namun belum dapat meningkatkan pertambahan tinggi tanaman, jumlah daun, berat basah akhir, berat kering akhir dan laju pertumbuhan relatif. Kombinasi jenis media tanam tanah + kompos dapat meningkatkan persentase berkecambah sebesar 73,33% dan kecepatan tumbuh benih sebesar 3,40%. Penelitian ini sangat penting dalam penyiapan bibit siap tanam dalam budi daya V. pinnata.Abstract Seedling using seed extraction method has not been explored much and it needs to add soil enhancers to increase seedling growth. This research aims to determine the effect of seed extraction and combinations of planting media to seeding Laban (Vitex pinnata L. Kuntze). This research used a complete randomized design with two treatment factors namely seed extraction (A0= wet extraction, A1= dry extraction) and combinations of plant medium (M0= soil, M1= soil + sand, M2= soil + compost, M3= soil + cocopeat) were repeated three times each. The data were analyzed by using variance test (ANOVA) at 95% level of confidence and continued using Duncan test at 95% level of confidence. The result showed that the dry seed extract treatment increased the average of germination percentage by 65.83% and seed growth rate about 3.295% but could not increase plant height, leaf number, final wet weight, final dry weight dan relative growth rate. The combination of planting media  + compost increased the germination percentage by 73.33% and the seed growth about 3.40%, but not yet able to increase plant height, leaf number, final wet weight, final dry weight and relative growth rate of laban plant. This research is very important in preparing ready-to-plant seedlings in V. pinnata cultivation.

Effect of seed mass on early seedling growth of five eastern white pine (Pinus strobus L.) families under contrasting light environments

2004 ◽  
Vol 82 (11) ◽  
pp. 1645-1655 ◽  
Author(s):  
William C Parker ◽  
Thomas L Noland ◽  
Andrée E Morneault
Keyword(s):  
Growth Rate ◽  
Seedling Growth ◽  
Natural Regeneration ◽  
Seed Mass ◽  
Pinus Strobus ◽  
White Pine ◽  
Eastern White Pine ◽  
Relative Growth ◽  
Early Seedling Growth ◽  
Early Seedling

The strong influence of seed mass on early seedling growth of forest tree species is well established, but the ecological role of intraspecific variation in seed mass on natural regeneration is poorly understood. Wide variation in initial spatial patterns of natural regeneration of eastern white pine (Pinus strobus L.) between managed and undisturbed white pine forests of the Great Lakes region of North America has been attributed to differences in understory light levels and the frequency of substrates suitable for germination and seedling establishment. To explore the potential influence of seed mass on these observed patterns, the interaction of seed mass and light on early growth of white pine was investigated in a greenhouse study. Seedlings of five half-sib families differing in mean seed mass were grown for 8 and 14 weeks under moderate and low light conditions representing managed and undisturbed pine stands, respectively. Family differences in seedling biomass and root system development under each light environment were associated with positive, linear relationships with mean seed mass. Family and seed mass had a comparatively weak influence on biomass partitioning and relative growth rate. Moderate light improved seedling growth regardless of seed mass, but relative expression of seed mass effects on seedling traits was unaffected by light environment. These results suggest differential recruitment of white pine in managed and undisturbed stands is unrelated to variation in seed mass.Key words: biomass allocation, eastern white pine, greenhouse experiment, natural regeneration, relative growth rate, seed mass.

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