Claim 1: a Brassica plant or parts of the same genes that comprise at least two DA1, where at least one of a First DA1 Gene allele is an allele DA1 Mutant, in which the Mutant allele that Codes for a DA1 DA1 Mutant Protein is in a position corresponding to the Position of SEQ ID no. 2 358 amino acids other than arginine.Claim 15: Seeds of Brassica plants according to any one of claims 1 to 14.18: a claim to identify a Mutant allele DA1 method as described in claim 1 or 2 in a Biological Sample which comprises subjecting the sample to a Biological reaction Amplification using a group of at least two primers, where these primers are chosen The group consisting of: a) a group of primers.Where one of these primers specifically recognizes the 5 and 3 flanking region of DA1 Mutant allele, and the other of these primers specifically recognizes the region of the mutation of the DA1 Mutant allele； and (b) a group of primers.Where one of these primers specifically recognizes the 5 and 3 flanking region of DA1 Mutant allele and the other of these primers specifically recognized in the junction region between the 3 or 5 flanking region and the region of the mutation of the DA1 Mutant allele, respectively.Claim 23: a method to increase the weight of a Thousand Seeds, Seeds of Brassica, wherein Said method comprises introducing a First of a Mutant allele DA1 DA1 Gene as described in claim 1, in a plant of Brassica. Claim 27: Use of Plants according to any one of claims 1 to 14 to produce a crop of rape.Claim 29: Oil Cake or Seeds from the seed of claim 15 or 16.Reivindicación 1: Una planta de Brassica o partes de la misma que comprenden al menos dos genes DA1, en donde al menos un alelo de un primer gen DA1 es un alelo DA1 mutante, en donde dicho alelo DA1 mutante que codifica para una proteína DA1 mutante comprende en una posición correspondiente a la posición 358 de SEQ ID Nº 2 un aminoácido distinto a Arginina. Reivindicación 15: Semillas de las plantas de Brassica de acuerdo
