Effects of population structure on pollen flow, clonality rates and reproductive success in fragmented Serapias lingua populations

Aggregated movement and population structure are known in entomopathogenic nematodes, which are obligate insect parasites. Aggregation behavior in the absence of external stimuli suggests communication among individuals, often in the form of trail-following, which has not been shown by nematodes of any kind. Interactions among individuals are an essential basis of following behaviors and can have significant fitness consequences. We explored intraspecific and interspecific interactions among three Steinernema species (S. glaseri, S. carpocapsae, and S. feltiae) in terms of trail following, and fitness outcomes of following heterospecific individuals. We found that the following behavior is context dependent. Following behavior among conspecifics was significantly increased when the lead nematode had prior contact with host cuticle. However, we did not find a clear association between the following response to heterospecific IJs and their reproductive success in a co-infected host.

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Edge effect on the population structure and the reproductive success of two Bursera species

Botanical Sciences ◽

10.17129/botsci.775 ◽

2017 ◽

Vol 95 (1) ◽

pp. 9 ◽

Cited By ~ 2

Author(s):

Humberto Suzán-Azpiri ◽

Oscar O Ponce-González ◽

Guadalupe X. Malda-Barrera ◽

Victor H. Cambrón-Sandoval ◽

Israel G. Carrillo-Angeles

Keyword(s):

Population Structure ◽

Reproductive Success ◽

Solar Radiation ◽

Edge Effect ◽

Environmental Conditions ◽

Soil Compaction ◽

Deciduous Forest ◽

Initial Conditions ◽

Reproductive Potential ◽

Tropical Deciduous Forest

Background: Environmental conditions in edges of vegetation fragments affect life cycle characteristics of the native biota (edge effect). We evaluated the edge effect on two Bursera species, which are representative of the mature community of the tropical deciduous forest (TDF) in Mexico.Hypothesis. We expected a population structure reflecting the affectation to reproduction, survival and growth in the edges of TDF fragments.Studied species: Bursera fagaroides, B. Palmeri.Study site and years of study: Querétaro (Qro.), Apaseo el Grande (Gto.), México. Field survey: May-September 2012.Methods: Within each of nine TDF fragments, we drew plots in two environmental contrasting conditions (edge and interior), between which we compared the density, population structure and reproductive success of the two Bursera species, as well as estimators of the solar radiation and soil compaction.Results: Solar radiation and soil compaction were not different between environmental conditions. In both species density of individuals was larger in the edge, where individuals with middle and large sizes were predominant. Reproductive potential of individuals, and the viability and germination of their seeds were similar between edge and core environments.Conclusions: Density and population structure showed a congruent variation with higher rates of recruitment, growth and survival in the edge environment, which could have been present under initial conditions of greater incidence of radiation in the edges. The similarity currently observed in the solar radiation between edge and core areas of fragments, could be a result of the fast recovery of the canopy under conditions of higher light incidence in edges.

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Influence of exploitation on population structure, spatial distribution and reproductive success of dioecious species in a fragmented cloud forest in India

Biological Conservation ◽

10.1016/s0006-3207(99)00170-6 ◽

2000 ◽

Vol 94 (2) ◽

pp. 243-256 ◽

Cited By ~ 48

Author(s):

Hema Somanathan ◽

Renee M. Borges

Keyword(s):

Population Structure ◽

Spatial Distribution ◽

Reproductive Success ◽

Cloud Forest ◽

Dioecious Species

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The effects of mating probability on the population genetics of nematodes

Journal of Helminthology ◽

10.1017/s0022149x00016631 ◽

1998 ◽

Vol 72 (4) ◽

pp. 295-300 ◽

Cited By ~ 5

Author(s):

A. Galvani ◽

S. Gupta

Keyword(s):

Population Genetics ◽

Population Structure ◽

Reproductive Success ◽

Critical Element ◽

Probability Models ◽

Individual Host ◽

Host Parasite ◽

Parasite Populations ◽

Emergence Of Resistance ◽

The Relationship

AbstractWe review how constraints on the mating probability of female worms by segregation within individual host guts form a critical element in the parasite population structure of nematodes. We consider the effects of these constraints on the population genetics of nematodes under various assumptions regarding worm competition as reflected in the relationship between the abundance of a certain genotype within the gut and the probability of reproductive success. The consequences for the emergence of resistance to drugs and immunotherapy and implications for host-parasite coevolution are discussed. We also review evidence for genetic heterogeneity in parasite populations as a necessary prerequisite for the applicability of mating probability models designed to assess the population genetics of nematodes.

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