If the vegetable talk, what it will happen? We can guess lots of situatuions and I think if the vegetable say, I feel very scary. Because whenever I want to eat the vegetable, it says to me " Please don't eat me! "It seems like butcher livestock. So may be there will be objection of eating vegetables. Oh my god! If the group founds, how does human take many nutritions? Do they eat just meat or kind of artifical nutrition? It could be very serious problem.
However I don't want to write serious problem so I think another situation which is human and vegetable will be good friends. It means human grows vegetable which looks like pet. So for example, if some grow a tomato or a potato, when person give nutritions to it which will say "Thank you master or friend. ". It could be very good for some people who want to bring pet but they have a sort of allegy or fear of animal.
If some scientists invent that vegetable can say, the pet business will improve level and expand field. We can imagine we can talk with vegetables after invention. Sometimes it may have seroios problems but it might have positive things and develope language study. Anyway it is impossible in thesedays so just imagine and laugh!