Heritable variation and mechanisms of inheritance of spore shape within a population of Scutellospora pellucida, an arbuscular mycorrhizal fungus

被引:37
作者
Bever, JD
Morton, J
机构
[1] Univ Calif Irvine, Dept Ecol & Evolutionary Biol, Irvine, CA 92697 USA
[2] W Virginia Univ, Div Plant & Soil Sci, Morgantown, WV 26506 USA
关键词
arbuscular mycorrhizal fungi; asexuality; genetic variation; glomalean fungi; heritabilities; heterokaryon; spore morphology;
D O I
10.2307/2656768
中图分类号
Q94 [植物学];
学科分类号
071001 ;
摘要
Substantial variation was found among single-spore cultures established from a single population of the arbuscular mycorrhizal fungus Scutellospora pellucida. A common environment experiment demonstrated that five single-spore cultures differed in their average spore shape (as measured by length:width ratios) and size (volume) with interisolate heritabilities of offspring mean values of 0.96 and 0.87, respectively (0.66 and 0.43 for the shape and size of individual spores). The distribution of offspring spore shapes also differed in levels of variance, skewness, and kurtosis. In fact, these aspects of the distributions shifted with mean spore shape as predicted by the binomial distribution-the distribution expected due to the segregation of genetically diverse nuclei through dividing hyphae. Thus, the original parental spores generating these cultures appear to have contained genetically variable nuclei, which then segregate into the offspring spores to generate consistent differences in the mean, variance, skewness, and kurtosis of the distribution of offspring spore shapes. This nuclear segregation may be followed by the assemblage of novel combinations of nuclei through hyphal fusion. Together these processes are rarely considered mechanisms for the creation of novel genetic combinations and may contribute to the maintenance of the high level of heritable variation observed in this study.
引用
收藏
页码:1209 / 1216
页数:8
相关论文
共 32 条
[1]  
Alexopoulos CJ., 1979, Introductory mycology, V3rd ed
[2]  
[Anonymous], MYCOGENETICS
[3]   STATUS OF NUCLEAR DIVISION IN ARBUSCULAR MYCORRHIZAL FUNGI DURING IN-VITRO DEVELOPMENT [J].
BECARD, G ;
PFEFFER, PE .
PROTOPLASMA, 1993, 174 (1-2) :62-68
[4]  
BENTIVENGA SP, 1997, AM J BOTANY
[5]   THE GLYCINE-GLOMUS-BRADYRHIZOBIUM SYMBIOSIS .9. NUTRITIONAL, MORPHOLOGICAL AND PHYSIOLOGICAL-RESPONSES OF NODULATED SOYBEAN TO GEOGRAPHIC ISOLATES OF THE MYCORRHIZAL FUNGUS GLOMUS-MOSSEAE [J].
BETHLENFALVAY, GJ ;
FRANSON, RL ;
BROWN, MS ;
MIHARA, KL .
PHYSIOLOGIA PLANTARUM, 1989, 76 (02) :226-232
[6]   Host-dependent sporulation and species diversity of arbuscular mycorrhizal fungi in a mown grassland [J].
Bever, JD ;
Morton, JB ;
Antonovics, J ;
Schultz, PA .
JOURNAL OF ECOLOGY, 1996, 84 (01) :71-82
[7]   OBSERVATIONS OF NUCLEI IN VESICULAR-ARBUSCULAR MYCORRHIZAL FUNGI [J].
COOKE, JC ;
GEMMA, JN ;
KOSKE, RE .
MYCOLOGIA, 1987, 79 (02) :331-333
[8]  
Daniels B. A., 1982, Methods and principles of mycorrhizal research., P29
[9]   Inter- and intraspecific variation within the morphologically similar arbuscular mycorrhizal fungi Glomus mosseae and Glomus coronatum [J].
Dodd, JC ;
Rosendahl, S ;
Giovannetti, M ;
Broome, A ;
Lanfranco, L ;
Walker, C .
NEW PHYTOLOGIST, 1996, 133 (01) :113-122
[10]  
Falconer D. S., 1989, Introduction to quantitative genetics.