Soil improver
An N-fixing legume, Persian clover improves soil fertility and is considered to have a better soil improvement potential than berseem (Kumar, 1987). Persian clover can be intercropped with barley and ryegrass (Stout et al., 1997). Grass and cereal crops grown with Persian clover yielded 95% of the yield obtained with 200 kg N/ha (Thompson et al., 1997). In relatively infertile soils, Persian clover is a potent intercrop for rice (Schulz et al., 2000; Schulz et al., 1999a; Schulz et al., 1999b). As a short ley, Persian clover improves pest and disease control while enhancing the yields of other crops in the rotation and reducing fertilizer use (Thompson et al., 1997).
Feeding ruminants on protein-rich irrigated Persian clover may result in increased ammonia production in the rumen and a large N excretion to the soil (Stockdale, 1993c).
Competition with other species
In India, certain types of Persian clover are regarded as a weed in berseem fields (Suttie, 1999). While in vitro experiments showed that Persian clover has an allelopathic effect (though to a lesser extent than berseem) on germinating weeds (Maighany et al., 2007), the efficiency of Persian clover at preventing weed seed development was not confirmed by field trials (Uchino et al., 2011).
Biological control of aphids
Persian clover attracts aphidophagous syrphids (flower flies) that play an important role in reducing aphid outbreaks in vegetable crops (Bugg et al., 2008).