Cover crops as green mulching for weed management in rice

A field study was carried out in 2017 and 2018 two Italian rice farms (at Livorno Ferraris Rovasenda) to assess the effect of using cover crops as green mulching on weed control yield. Three different fields were sown each site after harvest with either Vicia villosa, Lolium multiflorum, or a mixture both (V. villosa 40% + L. multiflorum 60%); at Rovasenda, small percentage Brassica napus Triticale also present mixture. An additional sites without crop considered reference. Rice broadcasted within May. After few days, terminated half roller-crimper, while other half, it by shredding. Within 10 flooded for about week promote degradation biomass. Then, cultivated flooding conditions further control. Weed density evaluated three times during growing season. At harvest, yield index determined. Mixed nested ANOVAs performed species, termination technique, interaction between year. showed high biomass before termination, V. had more variable development. growth limited because combination scarce emergence due sod-seeding frost damage. In general, significantly affected density. The best suppression observed mix values <40 plants m–2 recorded 2018. sites, years. highest (>5 t ha–1) shredded Rovasenda 2017. Generally, lower yields (1-3 sites. methods did not affect results highlighted that could reduce infestations, even though alone is able avoid development completely. Some critical issues technique observed, such need good establishment which eventually abundant production significant suppression. Highlights - Green reduces pressure, but should be integrated techniques. Hairy vetch poor low temperatures. ryegrass tolerant temperatures contained growth. Cover higher probably related number species (crimping shredding)