Effects of Organic Manures and Non-chemical Weed Control on Wheat: I-Plant Growth and Grain Yield

Organic wheat yield is limited by climatic and agronomic factors including nutrient deficiency, weed competition and no suitable cultivars. The effects of organic manures and non-chemical weed control on grain yield of wheat were investigated during the 2006-07, 2007-08 and 2008-09 growing seasons, in Erzurum (Turkey) rain-fed conditions. The experiment contained three experimental factors in a factorial design: (1) cultivar (Doğu 88, Kırik), (2) weed control (weedy control, hand weeding, dense sowing) and (3) manure (unfertilized, mineral NP, Bio, Bio SR, Leonardit, Organic Manure, cattle manure). The modern cultivar Doğu 88 had significantly higher leaf areaindex, grain filling period, spikes per m2, kernels per spike, grain yield and harvest index than the local cultivar Kırik. On average of years, hand weeding and dense sowing increased grain yield by 9.2% and 7.7% compared to weedy control, respectively. Application of mineral NP resulted in the highest grain yield. Among the organic manures, the highest grain yield was obtained at cattle manure and Organic Manure, respectively. Cattle manure and Organic Manure increased grain yield of wheat by 25.6% and 23.2%, respectively, compared to unfertilized treatment. Improved performance in response to treatments was generally related to spikes per m^2. Doğu 88 should be preferred to local cultivar Kırik. Dense sowing appears to be a useful method to provide the wheat a competitive advantage against weeds. As a result, cattle manure can be used for improvement of grain yield of wheat and soil fertility under rain-fed conditions.