Effects of manure injection tool type and tool spacing on soil nutrient levels and spring barley performance

摘要

A three-year field trial was conducted to study the effects of two manure injection tool types and three tool spacings on soil nutrient levels and crop response in a 2 x 3 factorial experiment. Liquid swine manure was injected using coulter and furrower injectors at 300- (S300), 600- (S600), and 900-mm (S900) tool spacings. Extractable soil NO_3-N, NH_4-N, P_2O_5, K, SO_4-S, pH, and electrical conductivity (EC), plant number of tillers, heads, and main stem length, plant biomass, grain and straw yields, total N and P in plant biomass, grain, and straw were measured. Application of manure with a furrower proved to be advantageous over a coulter in many ways. Use of a furrower resulted in 40 to 60% higher soil NO_3-N than a coulter at 0-300 mm soil depth at the time of rapid plant development in the second and third years of the experiment. Furthermore, use of a furrower resulted in 10% more plant biomass, 13, 3, and 16% higher total N in plant biomass, grain, and straw, respectively, and 2.5 and 13%higher total P in grain and straw, respectively, compared to use of a coulter in the first year of the experiment. Increased tool spacing decreased total N in plant biomass, grain, and straw. Soil nutrient levels also decreased with increase in tool spacing in one year of the study. In the other years, S300 resulted in higher soil NO_3-N and NH_4-N at 0-300 mm soil depth than S600. Plant number of tillers, heads, and main stem length in S300 were in some cases equivalent to and in other cases higher than those of S600 and S900.