Salinidade E Manejo Da Fertirrigação Em Ambiente Protegido. I: Efeitos Sobre O Crescimento De Meloeiro.

Abstract

SALINIDADE E MANEJO DA FERTIRRIGAÇÃOEM AMBIENTE PROTEGIDO. I: EFEITOS SOBRE O CRESCIMENTO DE MELOEIRO. Nildo da Silva Dias1; Sergio Nascimento Duarte2; José Francismar de Medeiros1; José Francisco Teles Filho21Departamento de Engenharia Ambiental, Universidade Federal Rural do Sem- Árido, Mossoró, RN. nildo@ufersa.edu.br2Departamento de Engenharia Rural, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, SP 1 RESUMO Com o objetivo de avaliar o efeito de diferentes níveis de salinidade do solo causados pela aplicação de fertilizantes e de manejos da fertirrigação no crescimento do meloeiro (Cucumis melo L.), conduziu-se um estudo em ambiente protegido na área experimental do Departamento de Engenharia Rural da ESALQ/USP, localizado no município de Piracicaba, SP. Os tratamentos foram compostos da combinação de dois fatores: salinidade inicial do solo aos níveis de 1,0; 2,0; 3,0; 4,0; 5,0 e 6,0 dS m-1 e dois manejos de fertirrigação, tradicional e com controle da condutividade elétrica da solução do solo. O delineamento estatístico adotado foi o de blocos casualizados completos com 4 repetições, sendo os fatores estudados arranjados em esquema fatorial de 6 x 2. Para avaliar o crescimento das plantas ao longo do ciclo selecionou-se, aleatoriamente, duas plantas de cada parcela a partir dos 19 dias após o transplantio. As variáveis analisadas foram altura de plantas, diâmetro de colo e área foliar. Os resultados mostraram que os efeitos da salinidade do solo sobre a altura e o diâmetro das plantas foram mais severos durante o desenvolvimento vegetativo inicial do que no inicio da frutificação, indicando uma possível adaptação da planta ao estresse salino ao longo do tempo. Não foi possível detectar diferenças expressivas causadas pelos dois tipos de manejo da fertirrigação. UNITERMOS: Cucumis melo L., solução do solo, condutividade elétrica. DIAS, N.S, DUARTE, S.N; MEDEIROS, J.F.; TELES FILHO, J.F. SALINITY AND FERTIGATION MANAGEMENT IN GREENHOUSES. I. EFFECTS ON MELON PLANT GROWTH 2 ABSTRACT In order to evaluate melon plant growth under different initial soil salinity levels caused by fertilizer application and different fertigation management, a study was carried out under greenhouse conditions, at the experimental field of Department of Rural Engineering of “Escola Superior de Agricultura Luiz de Queiroz”-USP, Piracicaba, Brazil. Each treatment was a combination of two factors: initial soil salinity (1.0, 2.0, 3.0, 4.0, 5.0 and 6.0 dS m-1) and two fertigation managements (traditional one and with monitoring of the soil solution electric conductivity). The statistical test was carried out in randomized blocks, arranged in a 6x2 factorial design and with four replications. 19 days after transplanting, two plants for each portion was selected at random to evaluate the plants growth along the crop cycle. The analyzed variables were plant height, stem diameter and leaf area. Results showed that soil salinity effects on the height and diameter of the plants were more severe during early vegetative growth than in beginning of fruiting, indicating a possible plant adaptation to saline stress along time. It was not possible to detect any significant difference caused by the two different proposed fertigation managements. KEYWORDS: Cucumis melo L., soil solution, electric conductivity.

Brackish water and organic matter in the substrate for the growth and quality of oiticica seedlings

“…Similarly, Diniz Neto et al ( 2014) found that increasing the salinity of irrigation water from 0.5 to 6.0 dS m -1 reduced oiticica seedling stem diameter. Consistent responses are reported in the literature for most plants irrigated with high salinity water (Dias et al, 2016;Sheldon et al, 2017). The application of the organic matter stimulated stem diameter growth in oiticica seedlings (Figure 2B).…”

“…Despite the importance of the species in the semi-arid region, oiticica is threatened with extinction because of increased deforestation in the Caatinga, mainly for the extraction of wood used in bread making, ceramics, and charcoal. Additionally, the climatic conditions of the semiarid area, including rainfall irregularities, low humidity, and high air temperature, as well as soil source material complexes (Ribeiro et al, 2016) that are rich in soluble salts (Oliveira et al, 2017) restrict the use of water and limit agricultural production (Dias et al, 2016).…”

Efeito da salinidade no crescimento inicial do maracujazeiro amarelo (Passiflora edulis f. flavicarpa Deg)

“…Para Dias et al (2006) em um trabalho realizado com salinidade na cultura do melão, os efeitos da salinidade sobre a altura média das plantas foram mais severos durante o desenvolvimento inicial do que no início da frutificação.…”

Management characteristics of Fertigation considering the salinization process on cultivation in soil and substrate

“…To SILVA et al (2007), besides the characteristics of the soil and of the soluble salts applied, the salinization is accelerated by the use of water with high level of chlorides, sulfates, carbonates and sodium bicarbonate, calcium and magnesium and of sources, without taking in consideration the qualitative properties of the water. According to DIAS et al (2006) and, waters of this nature can cause toxicity to the plants and physically weaken the soil, accelerating the soil degradation. highlight that the effects of excessive accumulation of soluble salts over the plants can be caused by difficulties of water absorption, specific ion toxicity and by the interference of salts in the physiological processes (indirect effects), reducing the growth and development of the plants.…”