Production Of Tomato Inbred Lines And New Cultivars Resistant To TYLCV By Marker-Assisted Selection

Tomato is a world-widely cultivated vegetable and susceptible crop to various diseases. There have been more than 40 kinds of plant disease, affecting the yield and quality of tomato. It is of high economic importance to produce new tomato varieties with disease resistance. Marker-assisted selection can be utilized to shorten the breeding period and speed up the process of breeding.Tomato yellow leaf curl disease (TYLCD) is one of the main diseases that cause huge yield losses in tomato all over the world. The pathogen of TYLCD is tomato yellow leaf curl virus (TYLCV), belonging to genus begomovirus, a kind of single plant DNA virus. TYLCV is mainly transmitted by Bemisia tabaci. This experiment is aimed to detect the segregation population of tomato for yellow leaf curl virus disease by Ty-1 marker, to breed TYLCV resistant tomato inbred lines. Then crossing combinations were produced with the TYLCV resistant inbred lines as male parents and other elite lines as female parents. The main results are as follows:1. The F2 materials of tomato collected by the laboratory from domestic and overseas market gave more than 100 segregation lines after 2-3 generations of selection. Those segregation lines were assayed for TYLCV-resistance combining field symptoms and Ty-1 marker assay, resulting in 96 homozygous Ty-1 resistance strains.2. Cross combination were set up using TYLCV-resistant lines as male parents and other elite lines as female parents by incomplete diallel. The corrsing combinations were evaluated in terms of fruit quality, yield, TYLCV-resistance and agronomic traits. We have obtained four crosses with good performance:12S1,12S2,12S20 and 12S25, providing material basis for breeding.