Abstract
Recent research has shown that plants can distinguish
genetically-related individuals from strangers (kin recognition) and
exhibit more cooperative behaviours towards these more related
individuals (kin discrimination). The first evidence for this was found
when Cakile edentula plants growing with half-sibs allocated relatively
less biomass to roots than plants growing with unrelated individuals,
indicating that kin recognition can reduce the intensity of competition
(Dudley & File, 2007). Since then, kin discrimination has been shown to
result in reduced competition for soil resources (Semchenko, Saar, &
Lepik, 2014), light (Crepy & Casal, 2015) and pollinators (Torices,
Gómez, & Pannell, 2018). On the other hand, allelopathy, plants
producing chemical compounds that negatively affect performance of
neighbour plants, has also been widely documented (Inderjit & Duke,
2003) and shown to profoundly affect local species coexistence and plant
community structure (Meiners, Kong, Ladwig, Pisula, & Lang, 2012). In
crops allelopathy can also be beneficial in suppressing weeds (Macías,
Mejías, & Molinillo, 2019). In the current issue, Xu, Cheng, Kong, and
Meiners (2021) published the first study to show that kin discrimination
can also affect the balance between direct competition for resources and
allelopathy, and this together may lead to improved weed suppression in
rice.