WHICH COVER CROP SPECIES ARE BEST USED IN SEMI-ARID CONDITIONS

H. R. Mashhadi, M. Sabet, N. M. Hosseini

Abstract: Cover cropping can cause many advantages to the cropping systems while little attention has been given to the utilization of cover crops in semi-arid climatic conditions. A 2-year field experiment was conducted in 2013–2014 growing seasons. The treatments consisted in three different winter cover crop species including cereal rye, rapeseed, hairy vetch and a weedy fallow (control), which were planted in a randomized complete block design with three replications. Growth, weed suppression and the amount of accumulated nitrogen in the biomass of cover crop species were evaluated at the time of incorporation. Both rapeseed and cereal rye produced the highest amount of aboveground biomass and showed a higher weed reduction compare with weedy fallow (85.88 and 78.3%, respectively), while the weed-suppressive ability of hairy vetch was 61.46% in compare to weedy fallow. In addition, cereal rye controlled the most dominant weed species (Sisymbrium officinale L.) more than 85% and declined its density to lower than 2 plants m-2. The total nitrogen accumulation in the aboveground biomass was higher in cereal rye and rapeseed (148.97 and 135.87 kg N ha-1, respectively) than in hairy vetch and weedy fallow (75.95 and 67.25 67.25, respectively). These results proposed that cereal rye and rapeseed were the most effective at biomass productivity, weed suppression and accumulating nitrogen and have great potential for using in semi-arid regions.

Keywords: cover crop; nitrogen accumulation; semi-arid condition; weed density; weed suppression

Date published: 2017-08-31