Resumo

ZAMUDIO-GONZALEZ, Benjamín et al. Harvest index with macro-nutrients in corn grain. Rev. Mex. Cienc. Agríc [online]. 2016, vol.7, n.5, pp.1077-1089. ISSN 2007-0934.

In the Highland valleys in Mexico State between 2 200 to 2 700 meters above sea level have low maize yields at high risk for climate and planting native with inadequate management practices. The years 2009, 2010 and 2011 (A1, 2,3) was evaluated planting of hybrid H-51 AE field with two densities (D1= 65K and D= 85 000 plants ha-1) and three annual sequences nitrogen (Ni) to the ground (with N always N1= N-N-N, the first year without nitrogen N2= 0-N-N and without three years N3= 0-0-0) and two doses of N (N= 300 and N= 1 80 kg ha-1). The combination of factors 2Di*3Ni= 6 treatments where:T1= D1*N1, T2=D1*N2, T3=D1*N3, T4=D2*N1, T5=D2*N2 and T6=D2*N3. Each year was added in kg ha-1 of P2O5, K2O, MgO, S and Zn treatments T1 to T3 with 0-90-90-44-50-3; and T4 to T6 with 0-45-45-0-0-0. The test was located at coordinates 19º 34’ 23.28” north latitude and 99º46’ 25.62” west longitude with altitude of 2 628 meters. The production of grain, forage and cob weighed; and the contents of macronutrients to estimate their harvest (IC) in corn grain effect of years, densities and sequences of N. The total contents of five macro-elements in kg ha-1 in the total biomass of corn average three years were: 187.9 of N, 30.6 of P, 69.9 of K, 24.1 of Mg and 11.6 of S. The index harvest of these elements in corn grain were: 0.45, ICP=0.75, ICK= 0.21, ICMg= 0.45 and ICS=0.43. There was correlation (R2) positive grain production and biomass content [N/P and Mg]; and content of biomass [N/P/K and S]. It was justified increase planting density but "high" fertilization N of the ground is not profitable in bad weather.

Palavras-chave : density; corn; N use efficiency; vegetable nutrition.

        · resumo em Espanhol     · texto em Espanhol | Inglês     · Inglês ( pdf ) | Espanhol ( pdf )