I think that you really are asking not about natural selection but about people selecting the plants based on those characteristics. This answer lists five characteristics that caused people to be more likely to pick a given plant. When they picked it, they helped it become more widespread.
The five characteristics are:
- The size of the fruit.
- Whether the seed of the plant is bitter.
- Whether the fruit is fleshy -- whether it has a lot of edible parts.
- Whether the seeds are oily -- this is a good thing because oil has lots of calories.
- Whether the fibers of the plant are long -- this is good for making into fabrics.