The effects of winter cover crops and the removal methods on Tobacco (K326) leaf qualitative characteristics and income

In order to investigate the impacts of winter cover crops and their removal methods on qualitative yield and income of tobacco (K326), an experiment was conducted as a split plot based- randomized complete block design with four replications. The main factor was cover crop (inclusing wheat, WM; Berseem clover, BC; hairy vetch, HV; and bitter vetch, CP) and sub-plots included removal treatments (Paraquat髩, PM; Glyphosate㋩,GM; Moving㋩, MM).
Materials ad On December 2011, the cover crop was sown in the farm and on 24 April 2011, using herbicide and stem cutting; they were eliminated and remained on the land surface as mulch. On late February 2012, tobacco was sown in seedbed and on 8 May 2012, the those transplants with 15-20 cm height, were moved to the farm and were transplanted into the much. 40 days after transplanting, the first leaf harvesting was conducted and their sugar, nicotine, phosphor, nitrogen, potassium, and chlorine contents were measured. Also, leaf yield was calculated.
Cover crops and mulch management had no significant effect on the nicotine and total leaf nitrogen content. Interacted effect of both factors was significant on the sugar content, as the maximum (15.95%) and minimum (11.27%) levels were related to WM-MM and HV-PM, respectively. Results revealed that sugar content in WM-GM, WM-PM and WM-MM decreased 22, 18 and 22% compared to control. The maximum and minimum potassium levels were related to WM (2.53%) and HV (2.15%), respectively, while related values were as 1.29% and 0.8% for phosphorus content, which were related to BC and WM, respectively. Combined treatment of mulch management × cover crop had significant effect on the tobacco fee.
Overall results revealed that cover crops along with mulch management could be considered as an appropriate alternative to improve qualitative characteristics of tobacco along with increasing the fee and farmer’s income. Also could be a proper alternative for chemical inputs to move toward sustainable agriculture goals.