The inflorescence of the tobacco Nicotiana tabacum L. is composed by floral axes whose number varies according to the variety, its flowers and capsules are distributed along them. There are different forms of regulating the quantity of flowers in the plant, but it is more practical if this is carried out eliminating some of the floral axes; it has been proven that if all the capsules are left in the plant they have not of good quality.

Given the importance of this problem in the Tobacco cultivation for different categories of seeds and those obtained from genetic resources preserved in the gene bank, this paper succeeded in determining the optimal regulation of inflorescence , for to help increase the quality of seed
. The experiment was carried out in irrigation conditions using Pelo de Oro (P-1-6) tobacco Variety. In the plantation the plants were distributed at random in a design of blocks with six treatments. The study of the different moments was carried out regulating the inflorescence. The treatments were the following ones: when open up from one to five flowers; when opens 25% of the flowers; when opens 50%; when opens 75%; when 100% and another treatment that consisted on plants regulated in all date. The inflorescence was regulated leaving five floral axes, three in the center and two laterals. After the threshing the seed was puts in capsules Petri, to count the percent of germinated seeds. The results were subjected to analysis of variance and multiple range test of Duncan. It was determined that the inflorescences regulated during the first days when the flowering occurs in the plant (up to about 25% of flowers open) behaved better than the regulated late