Temporal patterns of gamete production within individuals of Raphanus sativus (Brassicaceae)

1990 ◽  
Vol 68 (3) ◽  
pp. 480-486 ◽  
Author(s):  
Helen J. Young ◽  
Maureen L. Stanton
Keyword(s):  
Raphanus Sativus ◽  
Female Parent ◽  
Temporal Patterns ◽  
Developmental Differences ◽  
Pollen Size ◽  
Male And Female ◽  
Ovule Number ◽  
Pollen Number ◽  
Gamete Production ◽  
Phenotypic Gender

Previous studies on the deployment of energy to male and female gametes in plants have concentrated on differences among individuals or among related species. We documented temporal patterns of sex allocation within individual wild radish plants grown under controlled conditions. Lifetime investments in pollen and ovules were determined for four unrelated individuals of Raphanus sativus L. (Brassicaceae). Each individual produced 600–1100 flowers over the approximately 5-week flowering period. Mature floral buds were collected daily and ovule number, pollen grain number, pollen size, and pollen to ovule ratio (P:O) were determined for each. Variation in these traits was partitioned into variation among plants and among dates (representing flowering sequence). There was significant variation among plants for all characters, but because plants responded differently to date for three of the characters, further analyses were performed on a plant-by-plant basis. All plants showed significant reductions in pollen number and P:O through time, three plants showed a significant reduction in pollen size with time, and two plants showed a significant reduction in ovule number with time. The observed variation in phenotypic gender among these plants was not environmentally mediated because all plants were grown together in a controlled environment and therefore the differences in allocation to gametes were due to genetic or developmental differences. A result of intraspecific variation in gamete production is that the success of each individual as a male and female parent is likely to vary both within the population and within the flowering season. Key words: pollen to ovule ratio, Raphanus, pollen number, temporal changes, phenotypic gender, Brassicaceae, radish.

scholarly journals Microsporogenesis and pollen formation in Larch Sukachev (Larix Sukaczewii Djil.) on permanent forest seed plot in Semiluksky forestry

2021 ◽  
Vol 25 (3) ◽  
pp. 42-48
Author(s):  
E.E. Kulakov ◽  
◽  
A.I. Sivolapov ◽  
Keyword(s):  
Significant Proportion ◽  
Spherical Shape ◽  
Pollen Size ◽  
Seed Plot ◽  
Male And Female ◽  
Division Spindle ◽  
Sterile Pollen ◽  
Pollen Formation ◽  
Sukachev Larch

The formation of male and female generative buds in the Sukachev larch in the conditions of Voronezh in the second decade of August is considered. The behavior of chromosomes in the meta-, ana -, and telophase of the first and second divisions of meiosis is analyzed. In each phase, 150–200 microsporocytes were taken into account. According to the results of the conducted studies, it was revealed that the microsporogenesis of larch proceeded asynchronously. A significant proportion of the disorders are caused by chromosome lag and the formation of bridges, the formation of a hexad, and the release of chromosomes outside the division spindle. The viability of Sukachev larch pollen is estimated to be high. A small number of disturbances in the process of meiotic divisions and the formation of gametophytes did not lead to the formation of a significant amount of sterile pollen. The average pollen size varies between 82.18–86.4 microns. Pollen has a spherical shape

Reproductive success in a reintroduced population of a critically endangered shrub, Symonanthus bancroftii (Solanaceae)

2007 ◽  
Vol 55 (4) ◽  
pp. 425 ◽  
Author(s):  
Qigang Ye ◽  
Eric Bunn ◽  
Siegfried L. Krauss ◽  
Kingsley W. Dixon
Keyword(s):  
Reproductive Success ◽  
Pollen Viability ◽  
Natural Habitat ◽  
Female Parent ◽  
Clonal Plants ◽  
Critically Endangered ◽  
Positive Sign ◽  
Male And Female ◽  
Sterile Culture

Symonanthus bancroftii is a critically endangered dioecious shrub, with only one male and one female plant known in the wild. Micropropagated, clonal plants of the male and female parents were hand-pollinated. Seed was germinated in sterile culture and a subsequent daughter (F1) seedling was multiplied in vitro. Micropropagated plants of the original parents and daughter were reintroduced to a natural habitat site. We detail the first study of pollination biology and reproductive success in this extremely rare species. Floral morphology, flowering phenology, pollen viability, female receptivity and fruit set of reintroduced plants of S. bancroftii were investigated. Flower viability of S. bancroftii shows a 25-day maximum for male flowers, whereas non-pollinated female flowers remain viable for a maximum of 38 days (female parent) and 41 days (daughter), respectively. Flowering of reintroduced male and female plants overlaps from mid-June to early November. Pollen remained viable for at least 8 days after anther dehiscence. Maximum stigma longevity recorded was 28 days (female parent) and 39 days (daughter) and maximum ovule longevity varied from 13 days (female parent) to 28 days (daughter). The mean percentage of flowers setting fruit was 39 ± 13% for female parent plants and 48 ± 4% for daughter plants. Empirical reproductive success measures for male–daughter crosses generally exceeded those of the original parent crosses. The reproductive success of S. bancroftii so soon after reintroduction of plants is a positive sign indicating that rapid accumulation of a soil seedbank is feasible and is thus an important first step towards successful establishment of self-sustaining populations of this critically endangered species.

Morphotypic Differentiation in the South-Western Australian Restiad Lyginia barbata R.Br (Restionaceae)

1993 ◽  
Vol 41 (1) ◽  
pp. 91 ◽  
Author(s):  
TL Bell ◽  
JS Pate
Keyword(s):  
Growth Rates ◽  
Dry Matter ◽  
The Other ◽  
Spikelet Number ◽  
Male And Female ◽  
First Reproduction ◽  
Ovule Number ◽  
Culm Density ◽  
Rhizome Morphology ◽  
Western Australian

Study of Lyginia barbata across its distribution range in south-western Australia identified five distinctive morphotypes, viz. a tall-culmed, densely tufted fire-sensitive obligate seeder (S morphotype), a tall densely tufted fire-resistant resprouter (R1), a short flexuose-culmed, tufted resprouter (R2), a weakly clonal, semi-tufted resprouter (R3) and a short-culmed, widely spreading clonal form (R4). There was little variation within a morphotype between habitat locations and no evidence of intergrading of cohabiting morphotypes. Morphotype-specific differences were observed in culm height, rhizome morphology, culm density and spikelet morphology. Differences in reproductive biology related to the time of first reproduction in juvenile recruits, spikelet number per male and female culm, ovule number per female culm and seed : ovule ratio. Differences of a physiological nature were observed in seedling growth rates and proportional biomass (dry matter) allocations to culms, rhizomes, spikelets and seeds. Comparative quantitative scorings of the above features according to concepts of r- and K-selection rated the S form strongly r-selected, the R4 form equally strongly K-selected and the other forms (R1, R2 and R3) intermediate and with the R1 form possibly more r-selected than the others. It is suggested that the data provide a basis on which future taxonomic decisions regarding the taxon might be made.

Seasonal changes in components of male and female reproductive success in Raphanus sativus L. (Brassicaceae)

Oecologia ◽  
1989 ◽  
Vol 81 (3) ◽  
pp. 345-353 ◽  
Author(s):  
Susan J. Mazer ◽  
Robert R. Nakamura ◽  
Maureen L. Stanton
Keyword(s):  
Reproductive Success ◽  
Seasonal Changes ◽  
Raphanus Sativus ◽  
Female Reproductive Success ◽  
Male And Female ◽  
Raphanus Sativus L

Developmental differences in temporal patterns and potentiation of isolation-induced ultrasonic vocalizations: Influence of temperature variables

2002 ◽  
Vol 40 (2) ◽  
pp. 147-159 ◽  
Author(s):  
Kimberly S. Kraebel ◽  
Susan M. Brasser ◽  
James O. Campbell ◽  
Linda P. Spear ◽  
Norman E. Spear
Keyword(s):  
Temporal Patterns ◽  
Developmental Differences ◽  
Ultrasonic Vocalizations ◽  
Influence Of Temperature

scholarly journals Interspecific and Intergeneric Hybridization in Baptisia and Thermopsis

HortScience ◽  
2017 ◽  
Vol 52 (9) ◽  
pp. 1177-1181
Author(s):  
Susan M. Hawkins ◽  
John M. Ruter ◽  
Carol D. Robacker
Keyword(s):  
United States ◽  
North America ◽  
Female Parent ◽  
Woody Species ◽  
Interspecific Crosses ◽  
Intergeneric Hybridization ◽  
Male And Female ◽  
Intergeneric Crosses ◽  
Morphological Differences ◽  
Putative Hybrids

Interspecific and intergeneric crosses were performed between species in the genera Baptisia and Thermopsis with the goal of creating hybrids with the best qualities of both parents. Baptisia australis (L.) R. Br. was used as both the male and female parent in intergeneric crosses. Thermopsis chinensis Benth. ex S. Moore, T. lupinoides (L.) Link, and T. villosa Fernald & B.G. Schub. were used as male and female parents in both interspecific and intergeneric crosses. Pollen was collected from B. alba (L.) Vent., B. bracteata Muhl. ex Elliott, and B. lanceolata (Walt.) Ell. and used to make interspecific and intergeneric crosses. Putative hybrids were obtained from both interspecific and intergeneric crosses. Interspecific crosses produced a higher percentage of pollinations resulting in seed set and the number of seeds per pollination than intergeneric crosses. Morphological differences between parent species and progeny were evident in putative hybrids resulting from intergeneric crosses between T. villosa and B. australis and T. villosa and B. alba. Most putative hybrids bloomed during the second year after germination. Because seedlings could be obtained from both interspecific and intergeneric crosses, hybrids within and between the genera Baptisia and Thermopsis are feasible. The Fabaceae family contains 670–750 genera and 18,000–19,000 species. Baptisia (commonly called false or wild indigo) and Thermopsis (commonly named false lupine) of the Fabaceae belong to the tribe Thermopsidae, which comprises 46 species in six genera. All species in Thermopsis and Baptisia are herbaceous; they are the only two genera in Thermopsidae that do not have woody species. Thermopsis contains 23 species and has a wide-spread distribution with species endemic to Asia and much of temperate North America. Although Thermopsis is considered to have originated in central Asia, T. chinensis Benth. ex S. Moore and T. fabacea (Pallas) Candole are thought to have originated in North America and migrated over the Bering Land Strait to Asia. Three Thermopsis species, T. fraxinifolia Nutt. ex M.A. Curtis, T. mollis (Michx.) M.A. Curtis ex A. Gray, and T. villosa Fernald & B.G. Schub., are native to the southeastern United States. Baptisia contains 15–17 species that are endemic to the southeastern and midwestern United States.

Circatidal Moulting Rhythm in The Shore Crab Carcinus Maenas

1997 ◽  
Vol 77 (1) ◽  
pp. 277-279 ◽  
Author(s):  
P. Abello ◽  
C.G. Warman ◽  
E. Naylor
Keyword(s):  
High Tide ◽  
Carcinus Maenas ◽  
Temporal Patterns ◽  
Shore Crab ◽  
Male And Female ◽  
Large Numbers ◽  
Free Running ◽  
First Time

Late premoult females from precopula pairs of male and female Carcimts maenas (Crustacea: Brachyura) moulted at times of expected high tide in constant conditions in the laboratory. The data presents for the first time evidence of endogenous, circatidal (−12·4 h) moulting rhythms in a crustacean.Studies on the temporal patterns of moulting in crustaceans have elucidated rhythms of seasonal (annual or biannual), lunar (29·4 d), semilunar (14·7 d) and diel (24 h) periodicities (see Conan, 1985; Fernandez et al., 1994). Examples in the literature of so-called ‘tidal’ rhythmicity of moulting given by Conan (1985) are more correctly referred to as semilunar or neap/spring patterns. There appear to be no reported examples of true tidal (12·4 h) moulting rhythms. Also there is very little evidence in the literature that moulting rhythms phased to geophysical cycles are controlled endogenously. Most studies have been carried out in the field or under L:D cycles in the laboratory and only a few have been undertaken with animals in constant conditions (see Fowler et al., 1971; Bishop & Herrnkind, 1976; Nicol, 1989; Fernandez et al., 1994). Conan (1985) has reported moulting rhythms of circamonthly, circatidal (=circasemilunar) and circadian periodicities but his use of the prefix ‘circa’ is unusual since it more correctly describes free-running rhythms in constant conditions, not environmentally driven rhythms as in the examples quoted. In the present study we sought to determine whether moulting in the shore crab Carcimts maenas (L.) was tidally patterned and endogenous.Over a period of several days in the summer of 1991 large numbers of premoult female Carcinus maenas were obtained by searching for specimens associated with males in precopular pairs.

Factors Affecting Vertebral Variation in Mice

Development ◽  
1958 ◽  
Vol 6 (4) ◽  
pp. 645-659
Author(s):  
Anne McLaren ◽  
Donald Michie
Keyword(s):  
Eighteenth Century ◽  
Female Parent ◽  
Sex Linkage ◽  
Male And Female ◽  
Factors Affecting ◽  
Equal Strength ◽  
Sex Equality ◽  
Hereditary Factors

The historic controversy between ‘spermists’ and ‘ovist’' ended towards the close of the eighteenth century in a partial victory for both sides: sperm and egg were shown to be alike necessary for the genesis of a new individual. But the question of the relative biological contribution of the male and female parent remained open. A century later the biometrical school of Karl Pearson showed that in human stature, and a number of related characters, the respective influences of the mother and the father upon the offspring were of equal strength. The rediscovery at this time of Mendel's work seemed to offer the final and decisive proof of sex equality in heredity, for according to Mendel's system the number of hereditary factors supplied by each parent was of necessity equal. Somewhat paradoxically, Morgan's discovery in 1911 of the chromosomes as the bearers of the Mendelian factors was based on the first known exception to the rule of equality, namely, on sex linkage.

Pollen number and vigor contribute to effective ovule numbers among contrasting nitrogen utilization efficiency oilseed rapes genotypes before heart stage

2020 ◽  
Author(s):  
Xiao Guo ◽  
Yuyu Xie ◽  
Yunyou Nan ◽  
Xiaoming Wu ◽  
Biyun Chen ◽  
...  
Keyword(s):  
Oilseed Rape ◽  
Critical Period ◽  
Abortion Rate ◽  
Utilization Efficiency ◽  
Ovule Abortion ◽  
Nitrogen Utilization Efficiency ◽  
Ovule Number ◽  
Pollen Number ◽  
Main Factors ◽  
Pollen Vigor

Abstract Background: While no significant differences in initial ovule number were found among oilseed rape genotypes, there was a large variation in effective ovule number (EON), which determines the final seeds per silique (SPS), a critical component of yield. Up to date, on study has been focused on unraveling the pre-flowering main factors to restrict EON and identifying the critical period of EON formation among contrasting nitrogen utilization efficiency (NUtE) oilseed rape genotypes.Results: In this study, we selected 18 oilseed rape genotypes with different NUtE to identify the main factors that contribute to EON, and determine if genotypes differed in the critical period of EON formation under both field and pot experiments from 2016-2018. Our results showed the high NUtE genotypes also showed 14.3% higher NUtE, accompanied with 29.4% higher yield per plant and 21.1% higher SPS. The greater productivity of the high NUtE oilseed rape genotypes was associated with 44.1% greater pollen number, 23.5% higher pollen vigor, and 39.3% lower ovule abortion rate, compared to the low NUtE genotypes. In addition, at the heart stage, the high NUtE genotypes displayed higher silique net photosynthetic rate, surface area, biomass, and RNA expression levels, compared to the low NUtE ones. Taken together, this study indicated the pollen number, pollen vigor and ovule abortion rate contributed to the final EON of diverse oilseed rape genotypes; the critical period of determining EON among contrasting NUtE genotypes was at the heart stage.Conclusion: Increasing pollen number and vigor, and decreasing ovule abortion rate before the heart stage should be the prerequisite for breeders to improve yield and NUtE of oilseed rape genotypes.

scholarly journals Production of Triploid Hydrangea macrophylla via Unreduced Gamete Breeding

HortScience ◽  
2017 ◽  
Vol 52 (2) ◽  
pp. 221-224 ◽  
Author(s):  
Lisa Alexander
Keyword(s):  
Size Distribution ◽  
Female Parent ◽  
Unreduced Gametes ◽  
Pollen Size ◽  
Unreduced Gamete ◽  
Full Sibling ◽  
Male Gametes ◽  
Hydrangea Macrophylla ◽  
Diploid Cultivar ◽  
The Impact

Hydrangea macrophylla (Thunb.) Ser., florist’s or bigleaf hydrangea, is the most economically important member of the Hydrangea genus, which accounted for over $120,000,000 in U.S. nursery sales in 2014. Both diploid and triploid H. macrophylla cultivars exist and there is some evidence that triploidy leads to larger plant and floral structures. The diploid cultivar, H. macrophylla ‘Trophee’, was previously shown to have a bimodal pollen size distribution which may be indicative of unreduced gametes. We used H. macrophylla ‘Trophee’ as a parent in a series of crosses with other diploid H. macrophylla cultivars. The objective of this study was to evaluate reciprocal full-sibling H. macrophylla families for ploidy and phenotype, determine the impact of ploidy on phenotype, and determine the efficacy of unreduced gamete breeding. Diploids and triploids were found in the offspring pool with mean 2C genome sizes of 4.5 and 6.7 pg, respectively. All offspring from crosses with ‘Trophee’ as the female parent were diploid as expected. The full-sibling family with ‘Trophee’ as the male parent contained 94% triploids, supporting the hypothesis that the bimodal pollen size distribution of ‘Trophee’ reflects the presence of unreduced male gametes. Triploids had fewer, wider inflorescences than diploids. The stems of triploids were 16% thicker and their leaves were 20% larger than those of diploid full and half-siblings. Triploids had significantly larger stomata (9.0 μm2) than diploids (5.9 μm2). These results establish a link between ploidy and phenotype in plants of similar genetic background and support the efficacy of unreduced gametes in polyploidy breeding.

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