Substrates and time intervals of renewal of wastewater in production and post-harvest of the ornamental sunflower

Abstract

-Flower production in semi-hydroponic systems is a profitable alternative for generating income in communities of small farmers in the semiarid region of Brazil. This is because such a system of cultivation relates aspects of the climate, water and soil of the region, favoring the production of crops. In this work, the use of wastewater as a source of water and nutrients was studied, renewed at four time intervals (daily and every two, three and four days), and of three growth substrates (coconut fiber, sand and sugarcane bagasse), in the production and post-harvest period of sunflowers. These treatments were distributed in a completely randomised design and analysed in a 4 x 3 factorial with three replications, giving a total of 36 experimental units. It was found that plants under the wastewater renewal of every four days demonstrated characteristics compatible with commercial standards for sunflowers, if grown in sand or coconut fiber.Key words: Helianthus annus L.. Hydroponic system. Water reuse.RESUMO -A produção de flores em sistema semi-hidropônico é uma alternativa rentável para geração de renda em comunidades de agricultores familiares do semiárido brasileiro, isto porque este sistema de cultivo equaciona aspectos ligados ao clima, à água e ao solo desta região, favorecendo a produção das culturas. Neste trabalho estudou-se a utilização da água residuária como fonte de água e nutrientes renovado em quatro intervalos de tempo (diariamente, a cada dois, três e quatro dias) e três substratos de cultivo (fibra de coco, areia e bagaço de cana de açúcar) na produção e pós-colheita de flores de girassol; estes tratamentos foram distribuídos em um delineamento inteiramente casualizado, analisado em esquema fatorial 4 x 3, com três repetições, totalizando 36 unidades experimentais. Verificou-se que as plantas sob renovação da água residuária a cada quatro dias apresentaram características compatíveis com o padrão comercial para flores de girassol, desde que cultivadas em fibra de coco ou areia. Palavras

Vigor of zinnia seedlings produced in alternative substrate in trays with different cell size

“…However, the effect of pH to zinnia cultivate was no clearly evidenced, but it seems like this species grow up in a substrate with high pH. In previous studies zinnia plants had great development and production in a mix of substrates compost de leaf manure mix (silt + leaf manure + coconut compost; 1:1:1) or in silt alone with pH above 7.5 and 7.8, respectively (Riaz et al, 2008).…”

“…Many substrates can be used for this purpose, however, it is recommended to prioritize those substrates that are easily accessible and low cost; that present the suitable physical and chemical proprieties and allow obtain high-quality plants (Barbosa and Lopes, 2007). Therefore, it is possible to mention some components frequently used to produce seedlings of ornamental species, for example, substrates coming from composting of different organic wastes, sugarcane bagasse, carbonized rice husk, pinus husk and coconut fiber, as well as the mixing of these materials with soil or sand (Riaz et al, 2008;Ali , 2011Santos Júnior et al, 2014Silva et al, 2018). The great advantage of using these residues can be highlighted as the formulation of an alternative mix of substrates implying on lower production costs, reducing the environmental impact erstwhile produced by the discard of these materials (Sousa et al, 2011).…”