Effects of tillage timing, cover crop and weed control methods on sugar beet yield and quality

To evaluate the effects of tillage timing, cover crop planting and weed control methods on sugar beet (Beta vulgaris) yield and quality, a study was conducted in strip split plot design with randomized complete block design arrangement in four replications for two years starting from 2012 in Karaj, Iran. Main plots were allocated to tillage timing accompanied by cover crop including seedbed preparation in autumn without cover crop (a₁), seedbed preparation in autumn with barley planting on raw in autumn (a₂), seedbed preparation in autumn with broadcast planting barley as cover crop in autumn (a₃), seedbed preparation in spring without cover crop (a₄) and seedbed preparation in spring with row planting barley as cover crop in spring (a₅), and sub-plots consisted of three weed control methods including hand weeding, chemical control and without control. Analysis of variance results showed that weed management had significant effect on root yield and sugar yield. Mean comparison results illustrated that plots treated with chemical control and hand weeding were superior to control in terms of root yield and sugar yield with less impurities. Results also showed that tillage timing significantly influenced root and sugar yield so that the highest root and sugar yields were obtained in tillage practice in autumn without cover crop and hand weeding treatments. However, tillage timing had no significant effect on weeds fresh and dry weight.