Can plants recognize their own siblings?

Plants have been shown to be more competitive when they are grown alongside their unrelated neighbours as compared to their own siblings as shown in this report. It was found that plants grown beside strangers grow greater roots than those grown with their maternal siblings. It was proposed that plants secrete a protein or chemical signal specific to each plant's family. This signal can then be detected by other roots in the nearby area.

Why did I make thus post? Because I have seen elsewhere about vegetarianism being discussed regarding this issue. There are people who like to say "but being vegetarian also kills plants" or "plants are living too", now with this article we may even hear "plants can recognize their family". Does it mean that there is no point in being vegetarian since plants can also know family from non-family members? I do not think so.

First, I certainly do not think humans recognize family members and friends by mere their scent or sight etc only. That wouldn't explain things like why there are people out there who are able to read minds or communicate even when they are distance apart. What about animals? Even if they do not have the power to read minds, just being with them, we will be able to recognize how similar they are to us, it's something we know in our hearts.

Second, in terms of anatomy animals are more similar to us than plants. Well, perhaps you can say that the difference in anatomy does not mean plants cannot have the capacity to feel like us. But when we see animals being killed and a plant being pulled from the ground, the vast difference in reactions (whether or not there is any reaction from a plant), will allow us to see the 'feeling' capacity. Even the suffering of a small worm is obvious. When I was a kid, my classmate cut up a worm while we were doing some gardening in the school's garden. The suffering the worm experience was obvious from it's twisting and body. It was the same when my cousin burnt a worm which attacked his plant :s

Third, even if plants can really recognize their family members like us, it would still be better if we quit eating animals or at least lessen our intake of meat. This is due to the massive consumption of plant foods required to raise an animal. That would definitely kill more plants as well.