Markers Assisted Selection Of Potato Virus Y Resistance In Pepper

Pepper(Capsicum annuum L.) is an important vegetable crop. Disease is an important factor which effects yield and quality of pepper. Virus disease is the most important disease effecting pepper production,among them potato virus Y is one of the main virus on pepper in china. At present, few research on this field has been done in china.Inbred line CdM334 which Contains resistance gene pvr4,five inbred line 77013,75-7-3-1,83-58,83-60,83-163 with excellent horticultural characters but without resistance gene to PVY and their BC₂ population,BC₃ population,BC₄ population were used in this research. Using markers assisted selection and CAPS marker screen disease resistance plant.The results showed as following:1. Using CAPS marker detects donor parent and receptor parent. Donor parent got 444bp DNA fragment, receptor parent got 458bp DNA fragment. Significant difference was between them.2. Using CAPS marker screen BC₂,BC₃,BC₄ segregating population of five combinations(CdM334×77013,CdM334×75-7-3-1,CdM334×83-58,CdM334×83-60,CdM334×83-163), the practical separated ratio of the resistant individuals to the susceptible individuals were not significant with their segregation ratio accorded with 1:1 by X2 detection.3. The characters, plant height, node for first flower, leaf size, fruits size, of four generation segregation populations of five combinations(CdM334×77013,CdM334×75-7-3-1,CdM334×83-58,CdM334×83-60,CdM334×83-163)of each backcross combination were analyzed Variance by SAS. The result showed that there were no significant differences between backcross four generation segregation population and the recurrent parents on the characters (a=0.05).4. Backcross process graph showed that: in three backcross generation, the change of plant height of five combinations was basically identical, and were all the same to backcross parents. Changes of first flower nodes of them, expect CdM334×75-7-3-1 combination, were all basically identical, the leaf length and width of backcross populations had differences with donor parent and receptor parent in BC₂ generation but was equivalent to receptor parent in BC₄ generation. And the fruit length and width of BC₄ population was equivalent to receptor parent. However, the fruit length and width of CdM334×83-163,CdM334×75-7-3-1 combinations were longer than that of receptor parent in BC₄ generation.5.This resrarch gained five backcross four gene ration materials which include gene pvr4.This research results laid a foundation for speeding up varieties breeding of PVY Resistance.