WHEAT, MAIZE AND SAFFLOWER ROTATION IN CONSERVATION TILLAGE vs. TRADITIONAL TILLAGE

Abstract

Profitability of staple grains requires improvement in Northwest Mexico; one option to achieve this is to reduce mechanical tillage and the use of crop rotation, but it is necessary to evaluate the yield and the cost-benefit ratio in conservation tillage (CT) and crop rotation. The objective of this study was to evaluate the CT with rotation between wheat (Triticum durum Desf.), maize (Zea mays L.) and safflower (Carthamus tinctorius L.) compared to the traditional tillage system (TT), during the 2014-2015, 2015-2016 and 2016-2017 Autumn-Winter cycles, in Southern Sonora, Mexico. CIRNO C2008 wheat variety, Garañón corn hybrid, and CIANO-OL safflower variety were used. Wheat planting was in double-row with a density of 100 kg ha^-1 of seed, maize and safflower in single-row with 100,000 and 170,000 seeds ha-1, respectively. Plant height, days to flowering and physiological maturity, the weight of 1000 grains, and grain yield were measured in all crops. A completely randomized experimental design with factorial arrangement was used, the treatments were wheat, corn and safflower crops with and without rotation with each other in CT and without rotation in TT. The experimental plot consisted of eight rows 0.8 m wide and 100 m long. Plant height, days to flowering, days to physiological maturity, weight of 1000 grains and grain yield were measured. Yield of wheat/safflower in CT (7255 kg ha^-1) was higher than wheat/wheat in TT (P ≤ 0.05). The yield of maize/maize in TT and maize/wheat in CT was statistically equal (P ≤ 0.05), but maize/wheat in CT showed a higher benefit-cost ratio. Safflower/wheat in CT, with 2763 kg ha^-1, was statistically higher (P ≤ 0.05) than safflower/safflower in TT. Wheat, maize and safflower yields in CT were favored by crop rotation, which improves profit-cost ratio and gain.