TY - JOUR

T1 - Inbreeding depression and mating‐distance dependent offspring fitness in large and small populations of Lychnis flos‐cuculi (Caryophyllaceae)

AU - Hauser, Thure P.

AU - Loeschcke, Volker

PY - 1994/9

Y1 - 1994/9

N2 - The spatial structure of four Lychnis flos‐cuculi populations, varying in size and degree of isolation, was studied by comparing the fitness of offspring resulting from self‐pollination and pollinations by neighbouring plants, plants within the same population, and plants from other populations. Selfed offspring had the lowest fitness of the four offspring groups. No significant difference was found between the performance of offspring from pollinations by neighbouring plants and offspring pollinated by plants further apart but within the same population. A lower fitness of offspring from pollinations between neighbours would be expected if these matings, on average, yielded inbred offspring which suffered from inbreeding depression. These results imply that either a tight neighbourhood structuring is not present, or that the inbreeding depression for offspring by neighbours is too low to detect, although these are inbred. Crossings between populations produced offspring with a significantly higher fitness than offspring sired within populations. There were no significant differences in response to inbreeding among the populations, and differences in mean fitness among populations had no clear relation to the population size or degree of isolation. A reduced fitness of small populations due to inbreeding depression or a less severe response to experimental inbreeding due to purging of deleterious alleles is therefore not supported by our results.

AB - The spatial structure of four Lychnis flos‐cuculi populations, varying in size and degree of isolation, was studied by comparing the fitness of offspring resulting from self‐pollination and pollinations by neighbouring plants, plants within the same population, and plants from other populations. Selfed offspring had the lowest fitness of the four offspring groups. No significant difference was found between the performance of offspring from pollinations by neighbouring plants and offspring pollinated by plants further apart but within the same population. A lower fitness of offspring from pollinations between neighbours would be expected if these matings, on average, yielded inbred offspring which suffered from inbreeding depression. These results imply that either a tight neighbourhood structuring is not present, or that the inbreeding depression for offspring by neighbours is too low to detect, although these are inbred. Crossings between populations produced offspring with a significantly higher fitness than offspring sired within populations. There were no significant differences in response to inbreeding among the populations, and differences in mean fitness among populations had no clear relation to the population size or degree of isolation. A reduced fitness of small populations due to inbreeding depression or a less severe response to experimental inbreeding due to purging of deleterious alleles is therefore not supported by our results.

KW - Inbreeding depression

KW - mating distance

KW - population size.

UR - http://www.scopus.com/inward/record.url?scp=0028161726&partnerID=8YFLogxK

U2 - 10.1046/j.1420-9101.1994.7050609.x

DO - 10.1046/j.1420-9101.1994.7050609.x

M3 - Journal article

AN - SCOPUS:0028161726

VL - 7

SP - 609

EP - 622

JO - Journal of Evolutionary Biology

JF - Journal of Evolutionary Biology

SN - 1010-061X

IS - 5

ER -