Open AccessStrigolactone Deficiency Confers Resistance in Tomato Line SL-ORT1 to the Parasitic Weeds Phelipanche and Orobanche spp.
Author(s) -
Evgenia Dor,
Koichi Yoneyama,
Smadar Wininger,
Yoram Kapulnik,
Kaori Yoneyama,
Hinanit Koltai,
Xiaonan Xie,
Joseph Hershenhorn
Publication year - 2011
Publication title -
phytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.264
H-Index - 131
eISSN - 1943-7684
pISSN - 0031-949X
DOI - 10.1094/phyto-07-10-0184
Subject(s) - orobanche , biology , strigolactone , parasitic plant , lycopersicon , germination , rhizosphere , allelopathy , orobanchaceae , resistance (ecology) , botany , agronomy , horticulture , host (biology) , mutant , ecology , biochemistry , genetics , arabidopsis , gene , bacteria
The parasitic flowering plants of the genera Orobanche and Phelipanche (broomrape species) are obligatory chlorophyll-lacking root-parasitic weeds that infect dicotyledonous plants and cause heavy economic losses in a wide variety of plant species in warm-temperate and subtropical regions. One of the most effective strategies for broomrape control is crop breeding for broomrape resistance. Previous efforts to find natural broomrape-resistant tomato (Solanum lycopersicon) genotypes were unsuccessful, and no broomrape resistance was found in any wild tomato species. Recently, however, the fast-neutron-mutagenized tomato mutant SL-ORT1 was found to be highly resistant to various Phelipanche and Orobanche spp. Nevertheless, SL-ORT1 plants were parasitized by Phelipanche aegyptiaca if grown in pots together with the susceptible tomato cv. M-82. In the present study, no toxic activity or inhibition of Phelipanche seed germination could be detected in the SL-ORT1 root extracts. SL-ORT1 roots did not induce Phelipanche seed germination in pots but they were parasitized, at the same level as M-82, after application of the synthetic germination stimulant GR24 to the rhizosphere. Whereas liquid chromatography coupled to tandem mass spectrometry analysis of root exudates of M-82 revealed the presence of the strigolactones orobanchol, solanacol, and didehydro-orobanchol isomer, these compounds were not found in the exudates of SL-ORT1. It can be concluded that SL-ORT1 resistance results from its inability to produce and secrete natural germination stimulants to the rhizosphere.