Appraisal of artificial screening techniques of tomato to accurately reflect field performance of the late blight resistance

PLoS One. 2014 Oct 3;9(10):e109328. doi: 10.1371/journal.pone.0109328. eCollection 2014.

Abstract

Late blight (LB) caused by the oomycete Phytophthora infestans continues to thwart global tomato production, while only few resistant cultivars have been introduced locally. In order to gain from the released tomato germplasm with LB resistance, we compared the 5-year field performance of LB resistance in several tomato cultigens, with the results of controlled conditions testing (i.e., detached leaflet/leaf, whole plant). In case of these artificial screening techniques, the effects of plant age and inoculum concentration were additionally considered. In the field trials, LA 1033, L 3707, L 3708 displayed the highest LB resistance, and could be used for cultivar development under Polish conditions. Of the three methods using controlled conditions, the detached leaf and the whole plant tests had the highest correlation with the field experiments. The plant age effect on LB resistance in tomato reported here, irrespective of the cultigen tested or inoculum concentration used, makes it important to standardize the test parameters when screening for resistance. Our results help show why other reports disagree on LB resistance in tomato.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Disease Resistance*
  • Phytophthora infestans / physiology*
  • Plant Diseases / genetics
  • Solanum lycopersicum / immunology
  • Solanum lycopersicum / physiology*

Grants and funding

This research was supported by The Polish Ministry of Agriculture and Rural Development (Grant # HOR hn-801-15/13; “Searching for new sources of resistance to tomato late blight with regard to pathogenicity changes in Phytophthora infestans populations and attempts of markers identification linked with resistance genes”), carried out in the period 2008–2013. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.