The influence of different tillage practices on water content of soil and crop yield in vetch-winter wheat rotation compared to fallow-winter wheat rotation in a high altitude and cool climate

Fallow-winter wheat crop rotation under conventional tillage conditions is an agricultural system widely used in semi-arid regions. Water content of soil required for seed germination and plant growth can be improved performing tillage practices. Moreover, a crop rotation allowing sustainable and continuous production can be created. Therefore, the effect of four different tillage practices in a Hungarian vetch-winter wheat crop rotation (CR1) compared to fallow-winter wheat crop rotation (CR2) for water use efficiency was investigated in a semi-arid region with a high altitude (similar to 1750 m a.s.l.) for three years (2011-12, 2012-13 and 2013-14). Tillage practices consisted of; TS1: Conventional tillage (moldboard plough + cultivator + combined harrows + precision seeder); TS2: Reduced tillage-1 (cultivator + combined harrows + precision seeder); TS3: Reduced tillage-2 (rotary power harrow + precision seeder) and TS4: No-tillage (no-till seeder). Experiment was conducted applying randomized complete block design based on split-plot trial plan. The water content of soil in the CR1 was higher than the contents in the CR2. The TS4 practice significantly increased (P < 0.01) the water content of soil in all measurement periods (sowing, winter, spring, harvesting and the whole year) and in soil layers (0-30 cm, 30-60 cm and 60-90 cm) compared to the other tillage practices. Water contents of soil were the lowest in the TS1. For the 0-30-cm depth, compared to the TS1 practice, the TS4 practice provided higher water contents of soil by 21.3, 22.1, 14.4, 15.7 and 17.4% in sowing, winter, spring, harvesting and the whole year periods, respectively. Water contents in 30-60 and 60-90 cm soil layers in the TS4 practice also were higher than the TS1 practice values. Higher water contents of soil of the sowing period in TS4 provided higher stand density. Although the amount of weeds in winter wheat plots was the highest in the TS4 practice (67.4 kg ha(-1)) when considering three-year average values, grain yield in TS4 was also high (2652 kg ha(-1)) and statistically similar to TS1 (2762 kg ha(-1)). There was no clear effect on water use efficiency of winter wheat of the no-tillage practice compared to conventional tillage practice. Stand density and fodder yield of vetch were the highest in TS4. Our results indicated that the no-till vetch-winter wheat rotation could be more suitable than the conventional tilled fallow-winter wheat rotation due to the opportunity of high crop production in semi-arid regions. (C) 2015 Elsevier B.V. All rights reserved.