Effect of Winter Cover Crops Management on Quantity and Quality of Yield in Forage Sorghum (cv. Speed Feed)

In order to assess the effects of fertilizer management and return method of cover crops on quantity and quality of yield in forage sorghum (cv. Speed feed), an experiment was conducted as split plot in time based on randomized complete block design with three replications during 2012-2013 and 2013-2014, at Agriculture Research station University of Kerman. Method of return of cover crops including low tillage (disk) and no tillage (herbicides glyphosate cut) were assigned to main plots and fertilizer management of cover crops including cover crops (wheat, canola and peas) without the use of urea, cover crops with 25 tons per hectare farmyard manure (alternative farmyard manure with urea) and 75 kg.ha-1 urea (fertilizer partitioning between cover crop and main crop) and fallow (without cover crops) treatments were as the subplot. Amount of urea fertilizer decreased to half recommended amount for sorghum. Results showed that total green and dry forage yields of sorghum affected by fertilizer management and method of return for cover crops.Exception of protein percent, all of qualitative traits affected by fertilizer management and interaction between fertilizer management and method of return. The lowest quantity and quality yield of forage sorghum was related to cover crops without the use of urea treatments, but using of cover crops combined with farmyard manure or urea fertilizer partitioning can retain quantity and quality of yield of forage sorghum in spite of decreased urea fertilizer to half recommended amount for sorghum.