Nitrogen and potassium fertilization on the yield and intensity of the maize white spot

Revista Ceres

Gabriel Avelar Dornelas¹  Edson Ampélio Pozza¹  Paulo Estevão De Souza¹  Rodrigo Véras Da Costa¹  Adélia Aziz Alexandre Pozza¹  Leandro Alvarenga Santos¹ 

关键词: Nutritional stress;    Zea mays L.;    foliar diseases.;    Estresse nutricional;    Zea maysL.;    doenças foliares.;   

DOI  :  10.1590/0034-737X201562040004

来源: SciELO

【 摘 要 】

A plant's nutritional balance can influence its resistance to diseases. In order to evaluate the effect of increasing doses of N and K on the yield and severity of the mayze white spot, two experiments were installed in the field, one in the city of Ijaci, Minas Gerais, and the other in the city of Sete Lagoas, Minas Gerais. The experimental delimitation was in randomized blocks with 5 x 5 factorial analysis of variance, and four repetitions. The treatments consisted of five doses of N (20; 40; 80; 150; 190 Kg ha-1of N in the experiments 1 and 2) and five doses of K (15; 30; 60; 120; 180 Kg ha-1of K in experiment 1 and 8.75; 17.5; 35; 50; 100 Kg ha-1of K in experiment 2). The susceptible cultivar 30P70 was planted in both experiments. The plot consisted of four rows 5 meters long, with a useful area consisting of two central rows 3 meters each. Evaluations began 43 days after emergence (DAE) in the first experiment and 56 DAE in the second one. There was no significant interaction between doses of N and K and the disease progress P+. The effect was only observed for N. The K did not influence the yield and the severity of the disease in these experiments. Bigger areas below the severity progress curve of the white spot and better yield were observed with increasing doses of N. Thus, with increasing doses of N, the white spot increased and also did the yield.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License