Screening for new sources of resistance to Clavibacter michiganensis subsp. michiganensis (Cmm) in tomato
Sen, Y. ; Zhu, F. ; Vandenbroucke, H. ; Wolf, J.M. van der; Visser, R.G.F. ; Heusden, A.W. van - \ 2013
Euphytica 190 (2013)2. - ISSN 0014-2336 - p. 309 - 317.
bacterial canker - corynebacterium-michiganense - lycopersicon-esculentum - ssp michiganensis - seeds - pcr - quantification - crosses
Bacterial canker of tomato, caused by Clavibacter michiganensis subsp. michiganensis (Cmm), is considered the most serious bacterial threat, resulting in high damages in production areas. Worldwide, Cmm is subjected to quarantine regulations.There is no cultivar in market containing Cmm resistance genes. This project aimed to screen tomatoes or wild relatives of tomato for resistance to Cmm, to be used for starting breeding programs. We have screened 24 different wild accessions of tomato and found several new tolerant sources: Solanum pimpinellifolium GI.1554, S. parviflorum LA735 and S. parviflorum LA2072. We also confirmed the tolerance which was reported previously in S. peruvianum LA2157, S. peruvianum PI127829, S. peruvianum LA385, S. habrochaites LA407 and S. lycopersicum cv. IRAT L3. No immunity was found. Also accessions showing a low disease score still contained high titers of bacteria as determined by a dilution plating method, using tow selective media. These results were confirmed with a TaqMan real time PCR assay, which was developed to determine and quantify Cmm in planta
Seedling salt tolerance in tomato
Junming Li, J. ; Liu, L. ; Bai, Y. ; Zhang, Pujuan ; Finkers, H.J. ; Du, Y. ; Visser, R.G.F. ; Heusden, A.W. van - \ 2011
Euphytica 178 (2011)3. - ISSN 0014-2336 - p. 403 - 414.
quantitative trait loci - introgression line population - lycopersicon-esculentum - vegetative growth - cultivated tomato - bacterial canker - qtl analysis - fruit yield - germination - salinity
Soils with higher concentrations of salt are becoming more and more a constraint for many crops to obtain high yields. Wild tomato species, adapted to adverse environments, are a potential reservoir for genes underlying quantitative trait loci (QTL) related to salt tolerance in tomato. In this study two introgression line (IL) libraries derived from two different wild species, Solanum pennellii LA716 and Solanum lycopersicoides LA2951, were used to identify QTLs for salt tolerance in the seedling stage. In the S. pennellii IL library, four major QTLs were identified on chromosomes 6, 7 and 11. In the S. lycopersicoides IL library, six major QTLs were discovered which are located on chromosomes 4, 6, 9 and 12. Co-localization of QTLs on chromosome 6 in the two IL libraries and previously reports hinted that this locus might be conserved in the tomato crop. Three S. pennellii ILs (IL6-2, IL7-1 and IL7-5) harboring QTLs on chromosome 6 and 7 were crossed. Semi-dominance and dominance were shown for these three QTLs, and non-additive and epistatic interactions between them were observed