TWO-GENERATION ANALYSIS OF POLLEN FLOW ACROSS A LANDSCAPE. I. MALE GAMETE HETEROGENEITY AMONG FEMALES

Evolution ◽  
2001 ◽  
Vol 55 (2) ◽  
pp. 260 ◽  
Author(s):  
Peter E. Smouse ◽  
Rodney J. Dyer ◽  
Robert D. Westfall ◽  
Victoria L. Sork
Keyword(s):  
Male Gamete ◽  
Pollen Flow

scholarly journals TWO-GENERATION ANALYSIS OF POLLEN FLOW ACROSS A LANDSCAPE. I. MALE GAMETE HETEROGENEITY AMONG FEMALES

Evolution ◽  
2001 ◽  
Vol 55 (2) ◽  
pp. 260-271 ◽  
Author(s):  
Peter E. Smouse ◽  
Rodney J. Dyer ◽  
Robert D. Westfall ◽  
Victoria L. Sork
Keyword(s):  
Male Gamete ◽  
Pollen Flow

Pollen Flow and Optimal Outcrossing Distance

1983 ◽  
Vol 122 (1) ◽  
pp. 147-151 ◽  
Author(s):  
Keith D. Waddington
Keyword(s):  
Pollen Flow

Offsetting Effects of Wolbachia Infection and Heat Shock on Sperm Production inDrosophila simulans: Analyses of Fecundity, Fertility and Accessory Gland Proteins

Genetics ◽  
2000 ◽  
Vol 155 (1) ◽  
pp. 167-178 ◽  
Author(s):  
Rhonda R Snook ◽  
Sophia Y Cleland ◽  
Mariana F Wolfner ◽  
Timothy L Karr
Keyword(s):  
Heat Shock ◽  
Natural Populations ◽  
Adult Life ◽  
Reproductive Factors ◽  
Male Gamete ◽  
Wolbachia Infection ◽  
Accessory Gland ◽  
Sperm Production ◽  
Accessory Gland Proteins ◽  
Mating Conditions

AbstractInfection in Drosophila simulans with the endocellular symbiont Wolbachia pipientis results in egg lethality caused by failure to properly initiate diploid development (cytoplasmic incompatibility, CI). The relationship between Wolbachia infection and reproductive factors influencing male fitness has not been well examined. Here we compare infected and uninfected strains of D. simulans for (1) sperm production, (2) male fertility, and (3) the transfer and processing of two accessory gland proteins, Acp26Aa or Acp36De. Infected males produced significantly fewer sperm cysts than uninfected males over the first 10 days of adult life, and infected males, under varied mating conditions, had lower fertility compared to uninfected males. This fertility effect was due to neither differences between infected and uninfected males in the transfer and subsequent processing of accessory gland proteins by females nor to the presence of Wolbachia in mature sperm. We found that heat shock, which is known to decrease CI expression, increases sperm production to a greater extent in infected compared to uninfected males, suggesting a possible link between sperm production and heat shock. Given these results, the roles Wolbachia and heat shock play in mediating male gamete production may be important parameters for understanding the dynamics of infection in natural populations.

Pollen flow in distylous populations of Amsinckia (Boraginaceae)

1976 ◽  
Vol 54 (22) ◽  
pp. 2530-2535 ◽  
Author(s):  
Fred R. Ganders
Keyword(s):  
Pollen Flow ◽  
Progeny Testing ◽  
Self Incompatibility ◽  
Disassortative Mating ◽  
Pollen Loads ◽  
Self Pollination ◽  
Incompatibility System ◽  
Total Pollen

Stigmatic pollen loads were analyzed from naturally pollinated pin and thrum form flowers of Amsinckia douglasiana and A. vernicosa var. furcata. Pin stigmas captured more total pollen than thrum stigmas. Pins experienced either net self-pollination or random pollination. Thrum stigmas experienced significant disassortative pollination. Comparing pollen loads from intact and emasculated thrum flowers of A. douglasiana indicated that self-pollination and geitonogamy were relatively unimportant in the pollination of the thrum form. The level of disassortative pollination of A. vernicosa var. furcata does not appear to be high enough to account for the level of disassortative mating observed by progeny testing, suggesting that this species may possess an incomplete stylar self-incompatibility system such as has been reported in A. grandiflora.

Ultrastructural Localization of Intracellular Calcium During Spermatogenesis of Sterlet (Acipenser ruthenus)

2016 ◽  
Vol 22 (6) ◽  
pp. 1155-1161 ◽  
Author(s):  
Amin Golpour ◽  
Martin Pšenička ◽  
Hamid Niksirat
Keyword(s):  
Intracellular Calcium ◽  
Developmental Stages ◽  
Physiological Function ◽  
Male Gamete ◽  
Ultrastructural Localization ◽  
Acrosomal Vesicle ◽  
Acipenser Ruthenus ◽  
Calcium Deposits ◽  
Late Stages ◽  
Sterlet Acipenser Ruthenus

AbstractCalcium regulates many intracellular events such as growth and differentiation during different stages of gamete development. The aim of this study was to localize and quantify the intracellular distribution of calcium during different developmental stages of spermatogenesis in sterlet, Acipenser ruthenus, using a combined oxalate–pyroantimonate technique. The distribution of calcium was described in spermatogonium, spermatocyte, spermatid, and spermatozoon stages. In the spermatogonium and spermatocyte, calcium deposits were mainly localized in the nucleus and cytoplasm. The spermatid had calcium in the nucleus, developing acrosomal vesicle, and cytoplasm. Intracellular calcium transformed from scattered deposits in spermatogonia and spermatocyte stages into an unbound form in spermatid and the spermatozoon. The proportion of area covered by calcium increased significantly (p<0.05) from early to late stages of spermatogenesis. The largest proportion of area covered by calcium was observed in the nucleus of the spermatozoon. In conclusion, although most of the intracellular calcium is deposited in limited areas of the spermatogonium and spermatocyte, it is present an unbound form in the larger area of spermatids and spermatozoa which probably reflects changes in its physiological function and homeostasis during the process of male gamete production in spermatogenesis.

Observations on the ecology of hybridisation in the clubmosses (Lycopodiaceae)

1985 ◽  
Vol 86 ◽  
pp. 245-251 ◽  
Author(s):  
Benjamin Øllgaard
Keyword(s):  
Male Gamete ◽  
Interspecific Hybridisation ◽  
Parent Species ◽  
Spore Dispersal ◽  
Population Densities ◽  
Ecological Conditions ◽  
Highly Effective ◽  
Subterranean Habitat

SynopsisEcological conditions for intergametophytic mating and interspecific hybridisation in the clubmosses are discussed. Several features, including the number of recorded hybrids, records of gametophyte population densities, and conditions for movement of the male gamete in the soil, indicate that intergametophytic mating in Lycopodium is not especially impeded by the subterranean habitat, as has been commonly assumed. The evidence from one site indicates highly effective spore dispersal, and a greater ecological tolerance than expected for the species involved. Two cases are discussed in which hybrids have been formed between ecologically and/or taxonomically very different parent species, in the absence of one parent sporophyte, or with one of the parent species sporophyte poorly adapted to the hybrid habitat. The protected, relatively uniform, subterranean gametophyte habitat is thought to account for successful gametophyte growth and hybridisation between species of widely different sporophyte ecology.

Sign in / Sign up

Export Citation Format

Share Document