الفهرس 
Major sources and inheritance of TYLCV resistance in tomatoOnly 14 pages are availabe for public view
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Abstract
The present study was carried out at Horticulture Department,University of Florida, USA and Horticulture Department, Faculty of Agriculture, Kafr El-Sheikh University, during the period from the year 2010 to 2013. The objectives of this research were ; 1) fine mapping of Ty-2 gene on chromosome11 derived from S. habrochaites accession LA1777 2) field and genetic evaluations of tomato genotypes for resistance to TYLCV under Egyptian environmental condition and 3) identify chemical compounds associated with TYLCV resistance in tomato. 6. 1. Fine mapping for the Ty-2 gene on chromosome11 of tomato In Fall 2010, Castlerock cultivar was used as female parent and crossed with S. habrochaites accession LA1777 to obtain F1 seeds. F1 progeny were sib-mated to generate F2 population, which was phenotyped for TYLCV resistance and genotyped for five markers mapped on chromosome 11. Results showed that no symptoms were observed on LA1777 plants, indicating that it’s highly resistant to TYLCV. Conversely, all plants of Castelrock cv showed to be highly susceptible to TYLCV resistance, which rated 4. Evaluation of TYLCV disease severity for F2 population derived from LA1777 had an acceptable fit to a 3:1 ratio of resistant versus susceptible plants, supporting control of resistance by a single dominant gene. Based on genotype data, very highly significant correlation was observed between TYLCV resistance and molecular markers C2_Atg07960, TG36, CLEN-11-F24 and T0302, whereas no significant correlation was observed between TYLCV resistance and TG393 marker. Evaluating F2 progeny for TYLCV resistance localized the Ty-2 gene to a marker interval of 6.5 cM between C2_At1g07960 (82.5 cM) and T0302 (89 cM).