Effect of the trap crop, Solanum sisymbriifolium, on Globodera pallida, Globodera tabacum, and Globodera ellingtonae

Authors: DANDURAND, L - University Of Idaho; Zasada, Inga; LAMONDIA, J - Connecticut Agricultural Experiment Station

Submitted to: Journal of Nematology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/1/2019
Publication Date: 5/27/2019
Citation: Dandurand, L.M., Zasada, I.A., Lamondia, J.A. 2019. Effect of the trap crop, Solanum sisymbriifolium, on Globodera pallida, Globodera tabacum, and Globodera ellingtonae. Journal of Nematology. 51:1-11. https://doi.org/10.21307/jofnem-2019-030.
DOI: https://doi.org/10.21307/jofnem-2019-030

Interpretive Summary: Cyst nematodes (Globodera spp.) are among some of the most damaging plant-parasitic nematodes globally. The potato cyst nematode has been reported to cause up to 80% yield loss of potato. The discovery of the pale cyst nematode (G. pallida) in Idaho was met with alarm and efforts are underway to eradicate this nematode from the state. The primary method use for eradication is soil fumigation, which is expensive. Strategies to control cyst nematodes without reliance on fumigants are urgently needed. One such strategy may be trap crops. Trap crops promote hatch of these highly specialized nematodes, without allowing for reproduction, thereby deplete their populations, Research was conducted to evaluate the trap crop Solanum sisymbrifolium and its ability to reduce cyst nematode populations in soil. It was found that S. sisymbrifolium was very effective in reducing populaions of three cyst nematode species, with reductions in one growing season ranging from 25 to 68%. These results are significant because they provide growers with an alternative means to reduce cyst nematode numbers in soil leading to more effective non-chemical eradication and management of these production limiting pests.

Technical Abstract: The effect of the nematode trap crop Solanum sisymbriifolium was assessed against three Globodera spp., the potato cyst nematode Globodera pallida (in Idaho), the recently described Globodera ellingtonae (in Oregon), and the tobacco cyst nematode, Globodera tabacum (in Connecticut) in field trials. Factors which were considered in the field experiments included: final egg population densities/initial egg population densities for all species; the effect of planting and termination date of the trap crop on egg densities; the ability of G. pallida to parasitize potato after exposure to a S. sisymbriifolium trap crop; and, the Globodera spp. egg reduction in comparison to fallow or other crops. Encysted egg populations of all three Globodera spp. declined from 25 to 68% after trap cropping with S. sisymbriifolium. For G. pallida, S. sisymbriifolium reduced end of season numbers of encysted juveniles by 23 to 50%, and significantly decreased G. pallida reproduction by 99 to 100% on a subsequent potato crop compared to the bare soil treatment. For G. ellingtonae, the planting date of S. sisymbriifolium in May/June did not impact final egg densities. Rather, percentage reduction in G. ellingtonae egg densities was most influenced by the length of time to which nematodes were exposed to S. sisymbriifolium, with 30% and 81% reduction after 6 vs. 12 weeks of exposure, respectively. Similar levels of egg reduction were observed for G. tabacum after 12 to 14 weeks of exposure to the trap crop; G. tabacum population changes consisted of a 114% increase after susceptible tobacco, a 65% decrease after resistant tobacco, and an 88% decrease after S. sisymbriifolium. Our research demonstrates the widespread applicability of S. sisymbriifolium in reducing a diversity of Globodera spp. populations present in the U.S.