Related Experiment Video
Updated: Jun 24, 2026
Culturing and Screening the Plant Parasitic Nematode Ditylenchus dipsaci
Published on: January 31, 2022
Interrelationship of Meloidogyne hapla and Ditylenchus dipsaci on Resistant and Susceptible Alfalfa
Abstract:
Simultaneous inoculations of alfalfa with Meloidogyne hapla larvae and Ditylenchus dipsaci at 16, 20, 24, and 28 C did not depress penetration of either nematode in 'Nev Syn XX' -a selection resistant to M. hapla and D. dipsaci, 'Vernal 298' -a selection resistant to M. hapla and susceptible to D. dipsaci, 'Lahontan' -a cultivar resistant to D. dipsaci and susceptible to M. hapla, and 'Ranger' -a cultivar susceptible to both M. hapla and D, dipsaci. Infection with D. dipsaci depressed growth of susceptible 'Vernal 298' and 'Ranger' at all soil temperatures, except for 'Vernal 298' at 16 C. Infection with M. hapla alone did not depress growth of any of the alfalfas. A combination of M. hapla and D. dipsaci resulted in a synergistic weight depression on 'Ranger' at all soil temperatures. Inoculation of the four alfalfas with D. dipsaci 2, 4, 6, and 8 wk before inoculation with M. hapla at 16, 20, 24, and 28 C did not influence the resistance or susceptibility of 'Nev Syn XX,' 'Lahontan,' or 'Ranger.' However, galling of 'Vernal 298' by M. hapla was affected by soil temperature, plant age, and inoculation with D. dipsaci.
Insights
Nematode interactions in alfalfa varied by species and cultivar. While Meloidogyne hapla alone did not impact growth, Ditylenchus dipsaci infection reduced growth in susceptible alfalfa. Combined infections showed synergistic effects on susceptible
Area of Science:
- Plant Pathology
- Nematology
- Agricultural Science
Background:
- Alfalfa (Medicago sativa) is susceptible to various plant-parasitic nematodes.
- Meloidogyne hapla (root-knot nematode) and Ditylenchus dipsaci (stem and bulb nematode) are significant alfalfa pests.
- Understanding nematode interactions is crucial for developing effective resistance strategies.
Purpose of the Study:
- To investigate the effects of simultaneous and sequential inoculations of Meloidogyne hapla and Ditylenchus dipsaci on different alfalfa cultivars.
- To determine the influence of soil temperature on nematode penetration and subsequent plant growth.
- To assess the synergistic or antagonistic interactions between M. hapla and D. dipsaci in alfalfa.
Main Methods:
- Four alfalfa cultivars/selections with varying resistance to M. hapla and D. dipsaci were used.
- Plants were inoculated simultaneously or sequentially with M. hapla and D. dipsaci at different soil temperatures (16-28°C).
- Nematode penetration, plant growth (biomass), and galling were assessed.
Main Results:
- Simultaneous inoculation did not inhibit penetration of either nematode, regardless of cultivar resistance.
- D. dipsaci infection reduced growth in susceptible cultivars ('Vernal 298', 'Ranger') across most temperatures.
- M. hapla alone did not affect growth; however, combined infections with D. dipsaci caused synergistic growth depression in 'Ranger'.
- Sequential inoculation timing and soil temperature influenced M. hapla galling on susceptible 'Vernal 298', but not the resistance of other cultivars.
Conclusions:
- Alfalfa cultivar resistance plays a key role in managing nematode infections.
- Ditylenchus dipsaci poses a significant threat to susceptible alfalfa growth, especially at warmer temperatures.
- Synergistic interactions between M. hapla and D. dipsaci can exacerbate yield losses in susceptible alfalfa.
- Environmental factors like soil temperature and plant age can modulate nematode pathogenicity and host response.
