Molecular Marker Linked to Fusarium Wilt Resistance Gene in Tomato, Method for Obtaining the Same and Use Thereof

A method for identifying the resistance to Fusarium oxysporum f. sp. Physiological race 3 in tomato, characterized in that, the method comprises the following steps:

• extracting DNA from a tomato to be tested;
• amplifying the DNA of the tomato to be tested by PCR using the molecular marker linked to Fusarium wilt resistance gene in tomato as a primer, so as to obtain amplified products;
• and
• subjecting the amplified products to electrophoresis test and observing the band sizes of the PCR amplified products, wherein
• if the band size of the PCR amplified products is 897 bp, the tomato to be tested has the resistance to Fusarium oxysporum f. sp. Physiological race 3;
• and
• if the band size of the PCR amplified products is 687 bp, the tomato to be tested does not have the resistance to Fusarium oxysporum f. sp. Physiological race 3.

A method for screening a tomato single plant which is resistant to Fusarium oxysporum f. sp. Physiological race 3, characterized in that, the method comprises the following steps:

• subjecting susceptible tomatoes to crossbreeding with resistant tomatoes to obtain F1 generation, then subjecting the F1 generation to selfing to obtain the tomato single plants of F2 generation;
• extracting DNA from the tomato single plants of F2 generation;
• amplifying the DNA from the tomato single plants of F2 generation by using PCR serving the molecular marker linked to Fusarium wilt resistance gene in tomato as a primer, so as to obtain amplified products;
• and
• subjecting the amplified products to electrophoresis test and observing the band sizes of the PCR amplified products, wherein
• if the band size of the PCR amplified products is 897 bp, the tomato single plants of F2 generation are homozygous single plants which are resistant to Fusarium oxysporum f. sp. Physiological race 3;
• if the band size of the PCR amplified products is 897 bp+687 bp, the tomato single plants of F2 generation are heterozygous single plants which are resistant to Fusarium oxysporum f. sp. Physiological race 3;
• and
• if the band size of the PCR amplified products is 687 bp, the tomato single plants of F2 generation are homozygous single plants which are susceptible to Fusarium oxysporum f. sp. Physiological race 3.

A method for determining the purity of hybrid seeds derived from hybridization of the tomato which is resistant to Fusarium oxysporum f. sp. Physiological race 3 and the tomato which is susceptible to Fusarium oxysporum f. sp. Physiological race 3, characterized in that, the method comprises the following steps:

• subjecting a female parent of susceptible tomatoes to crossbreeding with a male parent of resistant tomatoes so as to obtain tomato seeds of F1 generation;
• extracting DNA from the tomato seeds of F1 generation;
• amplifying the DNA from the tomato seeds of F1 generation by using PCR serving the molecular marker linked to Fusarium wilt resistance gene in tomato as a primer, so as to obtain amplified products;
• subjecting the amplified products to electrophoresis test and observing the band sizes of the PCR amplified products, wherein
• if the band size of the PCR amplified products is double, the tomato seeds of F1 generation are hybrid seeds, and
• if the band size of the PCR amplified products is single, the tomato seeds of F1 generation are selfed seeds;
• and
• counting the numbers of the hybrid seeds and the selfed seeds respectively, calculating the ratio of the hybrid seeds to the selfed seeds to obtain the purity of the hybrid seeds derived from hybridization of the tomato which is resistant to Fusarium oxysporum f. sp. Physiological race 3 and the tomato which is susceptible to Fusarium oxysporum f. sp. Physiological race 3.