Nitrogen doses and water balance components at phenological stages of corn

Scientia Agricola

Monica Martins Da Silva²  Paulo Leonel Libardi¹  Flávia Carvalho Silva Fernandes¹ 

[1] ,UNICASTELODescalvado SP ,Brasil

关键词: internal drainage;    hydraulic conductivity;    actual evapotranspiration;    tensiometer;    no-till system;    drenagem interna;    condutividade hidráulica;    evapotranspiração real;    tensiômetro;    sistema de plantio direto;   

DOI  :  10.1590/S0103-90162009000400013

来源: SciELO

【 摘 要 】

Determining the intensity of the water balance components in the control volume of a soil, and consequently defining the most likely periods of occurrence of a water deficit in a crop, is an exercise that requires knowledge about soil, climate and plant factors. This research aimed to evaluate soil water balance components at phenological stages of corn (Zea mays L.) under no-till system, when fertilized with 60, 120, and 180 kg ha-1 of nitrogen. The field experiment was carried out in Piracicaba, State of São Paulo, Brazil, on a Typic Hapludox. Evaluations were made in the 2004/2005 and 2005/2006 corn cropping seasons, divided over three stages according to the plant's phenology. Runoff was not taken into account. Measurements were made for precipitation (P), internal drainage (D) (or capillary rise) at a 0.8 m depth, and water storage variation (Δh) in the soil layer from 0.0-0.80 m; actual evapotranspiration (ET) was considered the unknown quantity of the equation. Corn grain yield was evaluated as well. In general, the soil water balance components were modified by N doses, because the soil had been relatively smaller Δh in treatments involving N application than in the treatment without N, resulting in smaller D values in those treatments, which resulted in greater absorption by the plants and greater ET. As expected, the plant developmental stage II had a higher ET value.

【 授权许可】

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