Effect of Soil Tillage Methods and Wheat (Triticum aestivum L.) Residue on Weed Growth and Yield Response of Corn (Zea mays L.)

Changing tillage systems and plant residue application are regarded as suggested methods to improve weed management. A 3-year field experiment was conducted to evaluate the effects of soil tillage methods (conventional tillage (CT), reduced tillage (RT), and no-till (NT)) and wheat residue (residue preservation and removal) on weed growth and corn yield at Zarghan, Fars province. The experimental design was as split plot based on randomized complete block in three replications. Results showed that the lowest weed growth was obtained by CT method when wheat residue preserved while applying NT method enhanced perennial weed infestations. In other words, applying NT method increased perennial weed density up to 60% compared to CT and RT methods, but annual weed infestations decreased 40%. The kernel yield of corn (14447.64 kg ha-1) increased 34% when RT method accompanied by wheat residue compared to NT method. Applying CT method and residue preservation was maximized kernel number per cob (No. 576) and harvest index (36.82%) compared to RT and NT methods by four and 15%, respectively. It is concluded that, in consecutive corn cultivation, to grantee the corn yield potential and suppress weed growth applying RT method and preservation of 30% of wheat residue (standing residue with a height of 30 cm), is recommended.