RESUMEN
The aim of the present study was to develop a transformation system that may be useful for introducing agronomically and biotechnologically relevant traits into melon. The production of transplanted melon with maternal inheritance of the transgene could solve problems related to outcrossing between genetically modified crops and conventional crops or their wild relatives. By analyzing the main influencing factors systematically, the pollination time was ascertained and the pollen-tube pathway genetic transformation system was optimized. A screening system for resistant seeds from the T1 generation was established. The transformed seedlings were grown under standard field conditions and selected using a polymerase chain reaction-based analysis. The resistant plants were detected at a rate of 5%. These results indicate that enhanced production hastens the initiation of bisexual flowers, development of mature bisexual flowers, and fruit set in melon. We have established a melon transformation system based on the pollen-tube method.
Asunto(s)
Cucumis melo/genética , Genes de Plantas , Tubo Polínico/metabolismo , Transformación Genética , Cucumis melo/efectos de los fármacos , Kanamicina/farmacología , Plantas Modificadas Genéticamente , Plásmidos/genética , Tubo Polínico/efectos de los fármacos , Tubo Polínico/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa , Semillas/genética , Transformación Genética/efectos de los fármacosRESUMEN
In this study, molecular markers were designed based on the sex determination genes ACS7 (A) and WIP1 (G) and the domain in the Fusarium oxysporum-resistant gene Fom-2 (F) in order to achieve selection of F. oxysporum-resistant gynoecious melon plants. Markers of A and F are cleaved amplified polymorphic sequences that distinguish alleles according to restriction analysis. Twenty F1 and 1863 F2 plants derived from the crosses between the gynoecious line WI998 and the Fusarium wilt-resistant line MR-1 were genotyped based on the markers. The results showed that the polymerase chain reaction and enzyme digestion results could be effectively used to identify plants with the AAggFF genotype in F2 populations. In the F2 population, 35 gynoecious wilt-resistant plants were selected by marker-assisted selection and were confirmed by disease infection assays, demonstrating that these markers can be used in breeding to select F. oxysporum-resistant gynoecious melon plants.
Asunto(s)
Cucumis melo/genética , Cucumis melo/microbiología , Resistencia a la Enfermedad/genética , Fusarium , Marcadores Genéticos , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Secuencia de Bases , Cruzamientos Genéticos , Orden Génico , Genes de Plantas , Datos de Secuencia Molecular , Fenotipo , Polimorfismo Genético , Sitios de Carácter Cuantitativo , Alineación de SecuenciaRESUMEN
An efficient selection and plant regeneration protocol for Agrobacterium-mediated transformation, using cotyledon node zone-stem connection region of melon, has been developed. The new Agrobacterium-mediated transformation methodology, independent of organ culture, used the entire germinated seed as explants. The transformation system was maximized to maintain the integrity of melon itself, thus avoiding the limitations of traditional tissue culture methods. The transformation was carried out under a non-sterile environment. The incorporation of a selectable marker (neomycin phosphotransferase II) into the genome of transgenic plants was confirmed by PCR and Southern blot analyses. The transformation frequency based on the PCR was 13%. Transgenic melon plants were usually detected by PCR in less than 1 month after Agrobacterium inoculation, and seeds could be harvested in 3 months. The growth characteristics and morphology of the transgenic plants were identical to the untransformed wild-type plants. This method would be beneficial for facilitating the characteristics of gene functions and for boosting the manipulation of melon transformation for commercial purposes.