Duke Energy Convention Center, Exhibit Hall AB, Level 1, 1
Matias Ruffo, Mosaic Company, Buenos Aires, Argentina and Carlos Michiels, Mosaic de Argentina, Pergamino, Argentina
The Argentine Pampas are typically not considered to be zinc (Zn) deficient and as a consequence producers do not typically apply Zn fertilizer. However, Zn deficiency symptoms on maize have recently been detected. The objective ofthis study was toevaluate the response ofmaizeto Zn fertilizationand determinethe optimal application rate of thismicronutrient. Eightteen trialswere conductedin different locations inthe Pampasduring the 2009/10,2010/2011 and 2011/12 growing seasons.Treatments were: NP,NPS,and four rates ofZn(0.5,1, 1.5and 2kgZnha-1).The sources used weremonoammoniumphosphate(MAP11-52-0),MES10(12-40-0-10S) andMESZ(12-40-0-10S-1Zn). Nutrients rates ofN, PandSwere180 kgNha-1 (soilN+fertilizerN), 35kgPha-1and 20kgSha-1.These treatmentswere banded at planting.Statistically significantresponses were observedin twelve ofthe fourteensites. There was no negative response tothe application ofZn in any site.On average across18 sites, the optimal ratewas 1.5kgZnha-1, resulting in a 7.6%response(765kgha-1) compared to the NP treatmentand4.7%(487kgha-1) compared to the NPS treatment, with statistically significant differencesbetween treatments (p<0.1).The loss ofmaize yielddue toZndeficiencyindicatesthat this nutrientshould be incorporated into maize production systems in the Argentina Pampas.
