Banca de DEFESA: RICARDO DE CASTRO DIAS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : RICARDO DE CASTRO DIAS
DATA : 24/08/2018
HORA: 09:00
LOCAL: Sala Marcelo Nunes Camargo, n°24, Departamento de Solos
TÍTULO:

Evaluation of granular fertilizers based on potassium chloride and humic acids on the vegetative development of corn (Zea mays L.).

PALAVRAS-CHAVES:

Technologies. Fertilizer efficiency. Soil fertility

PÁGINAS: 80
GRANDE ÁREA: Ciências Agrárias
ÁREA: Agronomia
SUBÁREA: Ciência do Solo
ESPECIALIDADE: Fertilidade do Solo e Adubação
RESUMO:

DIAS, Ricardo de Castro. Evaluation of granular fertilizers based on potassium chloride and humic acids on the vegetative development of corn (Zea mays L.).2018. 66p. Dissertation (Master Science in Agronomy, Soil Science). Instituto de Agronomia, Departamento de Solos, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, 2014.

 

Potassium chloride (KCl) is the most used potassic fertilizer in Brazilian agriculture, however, it provides great losses of potassium in the soil through leaching. Moreover, the application of high doses of this fertilizer in the maize crop can be harmful, mainly in the initial phase of development, due to the high salt content of this fertilizer. Humic acids (HA) have high CEC and have the potential to decrease potassium losses by leaching and to minimize the damage caused by potassium chloride to maize, especially in the early stages of development. The aim of the present work is to evaluate the effect of the application of increasing doses of potassium chloride calculated on the basis of the surface area of the experimental units and the volume of soil, as well as the effect of the application in the development of the crop of corn until the end of the vegetative phase, aiming to establish a criterion for the calculation of doses of fertilizers used in greenhouse. The purpose of Chapter II is to evaluate the effect of potassic fertilizers based on potassium chloride granules with humic acids and to evaluate their effect on corn development and nutrition, as well as soil fertility parameters, as compared to the chloride of potassium. For that, two greenhouse experiments were conducted, in the experimental area of the Departamento de Solos of UFRRJ, using corn hybrid AG1051 as indicator plant. In Chapter I, doses higher than 120 kg.ha-1 of K2O, as well as the total application of the dose at planting time, delayed the emergence of maize seedlings. The calculation of the dose considering the volume of soil provided higher ICF, greater accumulation of K and lower pH variation in depth. The increase of the dose of potassium chloride promoted a linear increase in the dry mass and in the accumulation of K of stem and shoot of corn plants. When the dose was parceled out, there was a higher accumulation of P and K in the leaves and a lower potassium content in the soil on the surface. In chapter II, the increase in HA concentration in the fertilizers promoted a quadratic increase in seedling emergence, a linear increase in N accumulation by the crop and a quadratic reduction of the exchangeable Ca content in the 30-40 cm depth layer. The application of granulated KCl with HA isolated from vermicompost provided greater accumulation of P in relation to the commercial KCl, greater accumulation of K as compared to HA isolated from Peat and higher values of exchangeable Mg and exchangeable base sum in the layer from 0 to 10 in comparison with other fertilizers. The application of granulated KCl with HA isolated from vermicompost entailed the greater accumulations of dry mass and P in the roots compared to granulated fertilizer with AH isolated from vermicompost. The application of commercial KCl promoted a higher index of chlorophyll b compared to the fertilizer isolated with HA isolated from vermicompost, as well as promoted higher values of exchangeable Ca in the 30-40 cm layer in relation to the other fertilizers.

MEMBROS DA BANCA:
Presidente - 2213075 - EVERALDO ZONTA
Interno - 387263 - NELSON MOURA BRASIL DO AMARAL SOBRINHO
Externo à Instituição - PAULO CÉSAR TEIXEIRA - EMBRAPA