Delayed Sowing Improved Barley Yield in a No-Till Rainfed Mediterranean Agroecosystem

The effect of delaying sowing date and maturity class on no-till (NT) winter cereal performance was studied over two periods of 3 yr each. A 3 (sowing date) × 2 (maturity class) randomized complete block design was run for 3 yr with barley (Hordeum vulgare L.) (B-) (2006-2007 to 2008-2009) and soft wheat (Triticum sp.) (W-) (2009-2010 to 2011-2012) in northeastern Spain. Sowing dates corresponded to October (D1- the standard farming practice), November (D2), and December (D3). Maturity classes corresponded to early (-EC) and medium (-MC). Crop aboveground biomass, grain yield, and yield components were analyzed. The water use efficiency of aboveground biomass (WUEb) and grain yield (WUEy), and nitrogen use efficiency (NUE), were calculated. Averaging barley maturity classes and cropping seasons, D2 and D3 increased their grain yields 59 and 46%, respectively, when compared to D1. A greater number of grains per spike, as well as higher WUEb and NUE were observed in D2 and D3 compared to D1 in two of the three barley seasons. A greater thousand kernel weight (TKW) and higher WUEy were observed when sowing was delayed. Averaged across years, WEC presented a greater yield and aboveground biomass for D2 and D3 compared to D1, while for WMC there were no grain yield differences seen between the sowing dates, aboveground biomass or yield components. Our results demonstrate that, in western Mediterranean areas, sowing delay under NT can increase grain yield, WUE and NUE of winter barley, and also of wheat but only during wet years.

T his work was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain (Project Grants AGL2007- 66320-C02-01/AGR and AGL2010-22050-C03-01). Daniel Plaza- Bonilla received a “ Juan de la Cierva-Formación” postdoctoral grant from the Ministerio de Economía y Competitividad of Spain (ref. FJCI-2014-19570). We thank Silvia Martí, Carlos Cortés, and Miquel Betriu for their technical assistance.