Using the natural variation population of existing varieties and breeding new varieties by means of selection is called selective breeding, which is called seed selection for short. Genetic variation of population is the basis of selection, and the essence of selection is differential reproduction.

The selection and breeding of garlic mostly adopts single plant selection method.

Pre-selection and primary selection: select 100 excellent plants with good development, virus-free performance and comprehensive excellent characteristics as pre-selection plants from good alternative gardens by visual inspection, number them and publish them. Pre-selection can be carried out by stages, and the required indicators can be determined in different periods.

Check: the primary plants are propagated into vegetative seedlings and planted in the check garden, and the lines and sequences are not repeated. Detailed investigation records and statistical analysis items, such as yield factors, plant health, disease susceptibility, etc., should be formulated in the re-election stage, and special attention should be paid to whether there is virus infection. From the harvest period of garlic in the check garden, it is necessary to make a check. Generally, the yield and quality exceed the average value of the primary superior lines and can be used as a check line.

Final selection: The seedlings of the second-generation vegetative line propagated by the selected superior lines are planted in the final selection garden for 3-5 repetitions, and a plot is set for each repetition. The planting density is the same as that of the local production garden, so that it is convenient to further identify the main economic and biological characteristics of the selected lines and whether they are infected by viruses when the total number of plants is large and there are repetitions, so as to eliminate the errors caused by soil and viruses. At the same time, regional experiments were arranged in 2 ~ 4 producing areas with different ecological conditions to identify their yield, quality and adaptability under different production conditions. The final selection was made according to the results of the final selection nursery, regional test and field investigation, and the1~ 2 line with the best performance was taken as the final selection nutrition line. After the trial, the variety certificate will be issued, and it is agreed to be propagated and popularized in production.