Quality of jackfruit seedlings under saline water stress and nitrogen fertilisation

Abstract

The lack of good quality water for agriculture purposes regarding salts and quantity in relation to demand for the plants has, for more than 30 years, been forcing the use of restrictive water because of salinity issues in agricultural production systems worldwide. In Brazil, the situation is no different, in the semi-arid areas, there are reports of losses of seed germination, initial growth of seedlings and yield of crops of commercial importance due to the salinity of the water used in irrigation systems. Therefore, an experiment was carried out from June to September/2014 in a protected environment, with a plastic film on the upper base and a thin screen against insects on the sides, to evaluate the effects of salinity interaction between water irrigation and nitrogen fertilisation sources on soil salinity, initial plant growth and the quality of the jackfruit seedlings. The treatments were distributed in randomised blocks, in the factorial scheme 5 × 3, reference irrigation water of 0.3, 1.0, 2.0, 3.0 and 4.0 dS m -1 , in soil with and without ammonium sulfate and urea. An increase in the salinity of the irrigation water to 1.32 and 1.70 dS m -1 on the substrate without nitrogen stimulated an increase in the number of leaves and leaf area of the jackfruit seedlings. The ammonium sulfate was the nitrogen source that mainly contributed to the increase of soil salinity and to the reduction of the quality index of the seedlings. Despite the reduction of the Dickson quality index due to the salinity of the irrigation water and the nitrogen sources, the seedlings were suitable for cultivation. Key words: Artocarpus heterophyllus, water salinity, nitrogen fertilisers. ResumoA falta de água de boa qualidade para fins agrícola em relação aos sais e quantidade em relação à demanda pelas plantas tem, há mais de 30 anos, forçado o uso de água restritiva por problemas de salinidade em sistemas de produção agrícola em todo o mundo. No Brasil, a situação não é diferente; nas áreas semiáridas, há relatos de perdas de germinação de sementes, crescimento inicial de mudas e rendimento de culturas de importância comercial devido à salinidade da água utilizada em sistemas de irrigação. Assim, foi realizado um experimento de junho a setembro de 2014 em ambiente protegido, com filme plástico na base superior e tela fina nas laterais contra insetos, para avaliar os efeitos da interação salinidade entre irrigação e fontes de fertilização nitrogenada na salinidade do solo, crescimento inicial da planta e qualidade das mudas de jaqueira. Os tratamentos foram distribuídos em blocos casualizados, no esquema fatorial 5 × 3, referente às água de irrigação de 0,3; 1,0; 2,0; 3,0 e 4,0 dS m -1 , em solo com e sem sulfato de amônio e ureia. O aumento na salinidade da água de irrigação para 1,32 e 1,70 dS m -1 no substrato sem nitrogênio estimulou aumento no número de folhas e área foliar das plântulas de jaqueira. O sulfato de amônio foi à fonte de nitrogênio que mais contribuiu para o aumento da salinidade do solo e para a redução ...

Salts Waters and Biofertilizers in Jackfruit Seedlings Formation

“…Similar to this study, Oliveira et al (2017) observed in jackfruit seedlings that the height of the seedlings reduced with increasing water salinity from 0.3 to 4.0 dS m -1 . These authors evaluated the possible mitigating effects of nitrogen sources on salinity, as as well was evaluating with the application of biofertilizers in this study, in which was observed the salinity mitigation on the height of the seedlings by the biofertilizers, mainly the common input, and in the variety V2 (Figure 2A and 2B).…”

“…Yet, according Rodrigues et al (2017) these organic inputs, while providing an increase in the electrical conductivity of the substrate, stimulate the growth and production of vegetal biomass. The results are in agreement with Lima Neto et al (2016), Carneiro et al (2017) and Oliveira et al (2017) when they noticed an increase in the concentration of salts of the soil with irrigation of waters with increasing salinity.…”

“…Yet, the addition of ions with elevated electrical conductivity and the decline of pH in the soil saturation extract may have affected the seedling in phase soil soluble by increasing of sodium in the soluble phase of the soil, restricting too much cations, thus providing nutritional imbalance and especially in inhibiting the absorption of some macronutrients such as calcium, magnesium and potassium (Pessoa et al, 2010). Comparatively, the effects of saline stress on the caulinar diameter differed from those recorded by Oliveira et al (2017) in jackfruit seedling of the veriety solf wich showed declines of 5.62; 4.40 and 4.52 mm, resulting in loss of 1.06; 11.44 and 20.42%, respectively, between plants irrigated with water of 1.0; 2.0; 3.0 and 4.0 dS m -1 compared to those irrigated with lower levels of saline water (0.3 dS m -1 ) according with ( Figures 3A and 3B).…”

“…In this context, the need arises for the adoption of crop technologies that attenuate the deleterious effects of excess salts in the irrigation water during the whole phase of crop growth, especially during emergence and seedling formation. Among the materials used, we highlight the biofertilizer of bovine manure and the humic substances under irrigation with saline water, these inputs provide greater osmotic adjustment between the roots and the soil solution, minimizing the drasticity of the toxic effects of the salts on the plants (Aydin et al, 2012), thereby increasing the efficiency of water and nutrient uptake and, consequently, stimulating plant growth (Matsi et al, 2015;Oliveira et al, 2017).…”

Use of Salines Waters and Biofertilizers in Quality of the Seedlings From Passiflora edulis Evaluated by the Dry Phytomass

“…For the production of good quality seedlings, should be adopted efficient methodologies and, if possible, low cost methodologies (Dutra, Grazziotti, Santana, & Massad, 2012). However, mainly in arid and semi-arid regions, where the water scarcity has it become a preponderant factor, the production of seedlings is carried out it using ground-water, which in most cases contains high concentrations of soluble salts, impairing the germination and the growth of them (Souza & Peres, 2016;Oliveira et al, 2017). This inconvenience can transform productive lands into unproductive lands, therefore, it requires the adoption of technologies that either minimize the salinization of the soils with the water management or that allow to produce in areas compromised by salts without large losses of agricultural income and quality of production through the use of organic inputs with positive action on the physical characteristics of the soil and in the root environment of plants (Nascimento, Medeiros, Alves, Lima, & Silva, 2015;Medeiros et al, 2016).…”