Growth analysis of potted gerbera conducted with mineral fertilization and organic fertigation

Abstract

Potted gerbera is an ornamental plant that is widely commercialized in Brazilian markets. However, information on cultivation techniques is needed to meet growing demand, especially with regard to fertilization. This study was carried out to assess the growth of potted gerbera, Florist Red Black cultivar, with mineral and organic fertilization. The experiment was conducted in a greenhouse located at UNIOESTE – Cascavel Campus - PR. The experimental design was composed of randomized blocks with four replicates and five treatments. Treatments were defined according to the fertilization source, which were mineral (NPK) and organic. Organic fertilizers were obtained by diluting in water four organic composts from agroindustrial-waste composting processes. After obtaining composts, water dilution was performed, adjusting the nutritive solution electrical conductivity values. Gerbera plants were assessed fortnightly (0, 14, 28, 42, and 56 days after acclimatization) for leaf area and shoot dry matter, which were adjusted for time using the ANACRES program to obtain the leaf area ratio (LAR), relative growth rate (RGR), and net assimilation rate (NAR). Fifty-six days after acclimatization, plants were assessed for number of leaves, plant diameter, leaf area, leaves and inflorescences dry phytomass, stem height, head diameter, and stem diameter. The highest relative growth rates were obtained in plants grown with organic compost in treatment 3. However, the net assimilation rate, which indicates dry matter conversion efficiency, was highest in plants with chemical fertilization (treatment 1). La gerbera es una planta ornamental que es ampliamente comercializada en el mercado brasileno. Sin embargo, para satisfacer la creciente demanda, es necesario contar informacion sobre las tecnicas de cultivo, destacando la fertilizacion. Este trabajo se realizo con el fin de evaluar el crecimiento de gerbera en maceta, cultivar Floristeria Rojo Negro, fertilizado con un producto mineral y fertilizacion organica. El experimento se realizo en un invernadero ubicado en UNIOESTE – Cascavel Campus - PR. El diseno experimental fue de bloques al azar, con cuatro tratamientos y cinco repeticiones. Los tratamientos se definieron de acuerdo a la fuente de la fertilizacion mineral (NPP) y organico. La fertilizacion organica se obtuvo diluyendo cuatro compuestos organicos de proceso de compostaje de residuos agroindustriales en agua. Despues de la obtencion de estos compuestos, se ajustaron los valores de conductividad electrica de la solucion nutritiva. En las plantas de gerbera se evaluo cada dos semanas (0, 14, 28, 42 y 56 dias despues de la aclimatacion), el area foliar y la materia seca, que se ajusta en relacion con el tiempo con el programa ANACRES, con el fin de obtener la relacion de area foliar (LAR), tasa de crecimiento relativo (RGR) y la tasa de asimilacion neta (NAR). 56 dias despues de la aclimatacion, se evaluo en el numero de hojas, diametro de la planta, area foliar, hojas e inflorescencias de fitomasa seca, altura de tallo, diametro de la cabeza y el diametro del tallo. Las mayores tasas de crecimiento relativo se obtuvieron en plantas realizados con abono organico en el tratamiento 3. Sin embargo, la tasa de asimilacion neta, que indica la eficiencia de conversion de materia seca, fue mayor en las plantas con la fertilizacion quimica, en el tratamiento 1.