Identification and use of eg261, eg261 homologues, eg261 orthotics, eg261 parasites, eg261 fragments and their variants in order to improve, for example, resistance and / or resistance to plant pathogens such as soybean cyst nematode. Requirement 1: a method of producing a plant that is resistant and / or resistant to an additional pathogen,The characteristics include: (I) changing plant cells, the gene structure including nucleic acid sequence selected from the group, including: (a) a nucleic acid sequence, which encodes an eg261 polypeptide, with at least 97% characteristics, and selecting a sequence from the group. See SEQ ID No.9, 11, 12, 13, 14, 15, 25, 26, 27, 28, 29, 30, 31, 32, 33, 37, 38, 39, 43, 44, 45, 51, 52, 53, 54, 55, 57, 59, 61 and 63； (B) supplement of nuclear acid sequence (a)；(c) An additive for inverting (a) nucleic acid sequence；And (d) nucleic acid sequence reversal sequence (a)；And (II) to cultivate transgenic cells under appropriate conditions so as to regenerate and develop mature plants that are resistant and / or resistant to the changed pathogens.Identificación y uso de EG261, homólogos de EG261, ortólogos de EG261, parálogos de EG261 y fragmentos y variaciones de los mismos para alterar, por ejemplo, aumentar la tolerancia y/o resistencia a patógenos en plantas, tal como el nematodo de los quistes de soja. Reivindicación 1: Un método para producir una planta que presenta tolerancia y/o resistencia a los patógenos incrementadas, caracterizado porque comprende: (i) transformar una célula vegetal con una construcción genética que comprende una secuencia de ácido nucleico seleccionada del grupo que consiste en: (a) una secuencia de ácido nucleico que codifica un polipéptido EG261 que tiene al menos 97% de identidad con una secuencia seleccionada del grupo que consiste en SEQ ID Nº 9, 11, 12, 13, 14, 15, 25, 26, 27, 28, 29, 30, 31, 32, 33, 37, 38, 39, 43, 44, 45, 51, 52, 53, 54, 55, 57, 59, 61 y 63； (b) complementos de una secuencia de ácido
