Well there are three important factors that helped plant domestication: climate region, ancestry, and self pollination plants or "selfers". (pg 136-138)
Climate is important factor in plant domestication in the Fertile Crescent. It has a Mediterranean climate which means it has hot summers and wet winters. The plants have adapted to produce seeds that'll last the dry season and flourish when the rain comes. This allowed gatherers to stay in the area and plant these for the wet season.
The Ancestry of Fertile Crescent plants helped the domestication even further. That is, the ancestry of plants in the Crescent were already productive and abundant. The abundance of these plants allowed gatherers to stay in the area and harvest the grains.
To fertilize one's self is an important aspect in the Fertile Crescent. It basically helps plants keep some of their most important traits while other plants that do not fertilize themselves rick the chance of losing their traits that are important for us. Gatherers were helped by this aspect because the plants had a good "reproductive biology" and that at these plants can also be cross polinated at times to create a new set of plants with the traits that humans need and gain more nutritional value.
If these techniques were developed in Mesoamerica, there is a possibility that Domestication would have developed there. But instead, they are left with crops such as corn which Diamond described as having "lower protein content that posed significant nutritional problems." (pg. 138)