**2.2 Seed disinfection treatment**

The surface of the avocados was washed with soap and water, then the fruit was cut to obtain the seeds, which were rinsed with sterile purified water to eliminate remaining parts of the mesocarp. For *P. americana var. drymifolia*, the clean seeds were placed in 70% alcohol for 15 minutes and then planted in a laminar flow hood with superficial flaming. After that, part of the cotyledons was removed leaving a maximum of 1.5 cm2 flanking the embryo. For *P. americana var. americana*, the rinsed seeds were immersed in a 10% sodium hypochlorite solution for 10 min, then placed in the 70% alcohol solution for later sowing in a laminar flow hood under the conditions just described.
