Formação De Porta-Enxerto De Goiabeira Submetidas a Diferentes Salinidades Da Água E Adubação Nitrogenada

Abstract

RESUMOAs regiões semiáridas apresentam uma baixa disponibilidade de água de boa qualidade para irrigação, onde, muitas vezes, torna-se necessário o uso de águas salinas. Desta forma, objetivou-se avaliar o crescimento, produção e qualidade de porta-enxerto de goiabeira Paluma irrigado com águas salinizadas combinadas com doses crescentes de adubação nitrogenada. O experimento foi desenvolvido em ambiente protegido (casa de vegetação), utilizando-se o delineamento experimental de blocos casualizados, em esquema fatorial 5 x 4, com 4 repetições, sendo os tratamentos compostos de cinco níveis de condutividade elétrica da água -CEa (0,3; 1,1; 1,9; 2,7 e 3,5 dS m -1 ) e quatro doses de nitrogênio (70, 100, 130 e 160% de N) sendo a dose padrão 100% N (773mg de N dm -3 ). A dose de 115% de N promove os maiores valores nas taxas de crescimento absoluto e relativo de altura de planta no período de 50-110 dias após a emergência, sendo possível irrigação com água de até 1,33 dS m -1 , na formação de portaenxerto de goiabeira cv. Paluma promove redução de 10% nas variáveis de crescimento e no índice de qualidade das mudas. Palavras-chave:Psidium guajava; condutividade elétrica; nitrogênio. PRODUCTION OF GUAVA ROOTSTOCKS UNDER DIFFERENT WATER SALINITY AND NITROGEN FERTILIZATION ABSTRACTThe semi-arid regions present a low availability of good quality water for irrigation, where salt water is often required. In this way, the objective was to evaluate the growth, production and quality of guava rootstock cultivar Paluma irrigated with salinized waters combined with increasing doses of nitrogen fertilization. The experiment was carried out in a greenhouse (protected environment), using a randomized complete block design, in a 5 x 4 factorial scheme, with four replications, being the treatments composed of five levels of electrical conductivity of the water -ECw (0, 70, 100, 130 and 160% of N), the standard dose being 100% N (773 mg of N dm -3 ). The 115% N dose promotes the highest absolute and relative plant height growth

Saline stress and salicylic acid on growth and quality of guava ‘Paluma’ seedlings

“…This value was exceeded even under the highest electrical conductivity of irrigation water (ECiw -3.5 dS m -1 ). In this same sense, Souza et al (2017aSouza et al ( , 2017b) obtained guava seedlings with Dickson quality index above 0.20, corroborating the feasibility of using saline water, even with the sensitivity to salinity by this crop in the seedling stage. However, seedlings with higher Dickson quality index are more tolerant to adverse conditions.…”

“…Saline stress directly affects the synthesis, accumulation and allocation of biomass in seedlings (Bezerra et al, 2018b(Bezerra et al, , 2018cNascimento Neto et al, 2020). In guava rootstocks Souza et al (2017b) observed reductions in biomass allocation in roots, aerial part and total, with greater intensity on roots, while Souza et al (2017a) observed greater sensitivity to salinity in the aerial part. Dry biomass accumulation in guava plants is reduced in both the stem and leaves as observed by Sena et al (2018).…”

“…These factors can also be noticed in guava (Psidium guajava L.), and some researchers who evaluated the growth of seedlings irrigated with saline water, found that the increase in water salinity inhibited the height, stem diameter, number of leaves emitted per plant, absolute growth rates of stem diameter, dry phytomass of the aerial part, and root/ aerial part ratio (Souza et al, 2017a(Souza et al, , 2017bBezerra et al, 2018aBezerra et al, , 2018bSena et al, 2018;Veloso et al, 2018), affecting seedling quality (Souza et al, 2017a;Bonifacio et al, 2018). Guava tree is a crop sensitive to salinity, since reductions in its productive capacity occur when the electrical conductivity of irrigation water exceeds 3.0 dS m -1 (Cavalcante et al, 2005).…”

Saline pisciculture effluent as an alternative for irrigation of Croton blanchetianus (Euphorbiaceae)

“…Depending on the degree and exposure to salinity, a plant may lose water inside the roots, instead of absorbing water. This is due to the potential difference between the cells present in the root and the soil solution through a process known as plasmolysis (Souza et al, 2017b). It is important to highlight the increase in the RWC we observed at the highest ECw (Figure 1D).…”