<p>Factors that restrict the development of genetic transformation include the long cycle, extensive requirements for experimental conditions, and low survival and transformation rates. Especially for plants that obtain offspring through sexual reproduction. This study established the genetic transformation methods that are particularly suitable for it. First, a rapid <i>in vivo transformation</i> system of adventitious roots was developed using <i>A. rhizogenes</i> to infect normally growing watermelon stem nodes without requiring plant treatment, enabling the stable genetic transformation of adventitious roots. And the genetic transformation efficiency of adventitious roots reaches 100%. Second, the traditional genetic transformation system was improved using <i>A. rhizogenes</i> which induces rooting of explants and promotes the regeneration of adventitious buds. The genetic transformation efficiency of adventitious roots reaches 100% and adventitious buds reaches 40%, which is much higher than using <i>A. tumefaciens.</i> Third, in order to achieve shorten the regeneration cycle and high transformation efficiency, the genetic transformation method without tissue culture was established using <i>A. rhizogenes</i> to infect the seed. This genetic transformation efficiency of transgenic plants reaches 80%, and it is not limited by genotype. This study significantly improves the plant regeneration and low genetic transformation efficiency while promoting the rapid development of watermelon molecular breeding.</p>