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Parthenogenesis in the Two Races of Radopholus similis from Florida.
Journal of Nematology
|March 21, 2009
Summary
Parthenogenetic reproduction is possible in Radopholus similis, a nematode that typically reproduces amphimictically. Single larva inoculations resulted in all-female populations, indicating tychoparthenogenesis and environmentally induced sex determination.
Area of Science:
- Nematology
- Reproductive Biology
- Plant-parasitic nematodes
Background:
- Radopholus similis, a significant plant-parasitic nematode, typically reproduces amphimictically.
- Understanding alternative reproductive strategies is crucial for managing nematode populations.
Purpose of the Study:
- To investigate the potential for parthenogenetic reproduction in citrus and banana races of Radopholus similis.
- To determine the reproductive modes and sex determination mechanisms under specific inoculation conditions.
Main Methods:
- Single larval inoculations of Florida citrus and banana races of Radopholus similis.
- Observation of reproductive patterns and population composition over 80 and 180 days.
- Microscopic examination of female reproductive tracts to assess insemination status.
Main Results:
- Single larva inoculations led to all-female populations after 80 days, with evidence of tychoparthenogenesis.
- After 180 days, both male-female populations and cross-fertilization (approx. 95% insemination) were observed.
- Uninseminated females produced both male and female progeny, suggesting environmentally induced sex determination.
Conclusions:
- Radopholus similis exhibits facultative parthenogenesis, a deviation from its usual amphimictic reproduction.
- The study provides evidence for tychoparthenogenesis and environmentally influenced sex determination in this nematode species.
- Findings contribute to understanding nematode reproductive plasticity and potential management strategies.
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