Nutritional Evaluation of Forage Cactus Fertigated With Domestic Sewage Effluent

Abstract

The northeastern semiarid region faces some of the droughts of the last centuries, resulting in serious reductions of agriculture yields. The water scarcity for agricultural requires rational use practices and reuse of water, such as use of domestic effluent sewage. Alternatively, the use of treated domestic sewage effluent utilizing for irrigation of forage species, such as the forage cactus, can be highlighted. In order to evaluate the effects of fertirrigation with treated sewage effluent on mineral nutrient composition of forage cactus (Opuntia Tuna L. Mill, Mexican elephant ear), an experiment was carried out utilizing a split plot 3 x (4 + 1) with a randomized complete block design randomized block and four replications, being three planting density (66,667.00, 52,282.00 and 33,333.00 plants ha-1) and two water sources associated with irrigation frequency of plates fixed on 3.5 mm per irrigation (Frequencies of 2.3 days with water tap and 7, 14 and 21 days with Sewage Effluent) and cactus cultivated in Rainfed agriculturerainfed (control). The analyze of the nutritional contents of cladodes indicated that there was a significant effect of the intervals from irrigation events only for Ca and Mg concentrations. The highest levels of Ca and Mg were found with the irrigation frequency of 2.3 using tap water. The macronutrients concentration in greater quantity by the forage cactus were N e, K followed by, Ca, Mg and P. The nutritional balance indicated excess of K and P and deficiency of N, Ca and Mg, in this order.

Growth and biomass production of prickly pear in the second cycle irrigated with treated domestic sewage

“…Similar results were found by Lemos et al (2018) and Rocha et al (2017), in the first cultivation cycle. These authors observed that changes in prickly pear growth are slow in the initial stage of cultivation for all variables studied.…”

“…Similar results were obtained by Lemos et al (2018), who found a trend of greater thickness in cladodes of plants which received greater amount of water, at 75 DAP. Likewise, the measurements taken at 170 and 234 DASC demonstrated that the means of the treatments, either with or without significant differences, followed the same trend in which plants receiving a larger volume of water showed greater cladode thickness.…”

“…Cladode width response was similar to that of cladode length, with respect to the increase in the dimensions over time, showing mean values of 11.21, 11.77 and 15.05 cm, at 110, 170 and 234 DASC, respectively (Table 5). According to Lemos et al (2018), there is a direct relationship between cladode width and length in the initial growth stage of prickly pear, when the cladode elongates longitudinally and transversely at the same time.…”

“…Prickly pear -Opuntia sp., variety 'Orelhade-elefante Mexicana', was planted in October 2013 in a 2,205-m² area whose soil was classified as Argissolo Vermelho Amarelo (Ultisol) (EMBRAPA, 2013). The first experiment (LEMOS et al, 2018) aimed to evaluate prickly pear production and the physical and chemical impacts caused by the accumulation of nutrients in the soil and in the plant subjected to irrigation with treated domestic sewage, at 4 different intervals between irrigation events, with fixed depth of 3.5 mm per event and 3 planting densities. The second experiment, after the second cut, evaluated the performance of prickly pear plants under complementary irrigation with treated domestic sewage at 4 different irrigation intervals and the chemical impacts on the soil and on the plants, based on the effluent treatment efficiency and water quality for irrigation.…”

“…The water depth applied in each irrigation was 3.5 mm, which corresponds to half of the mean daily ETo historically recorded in years prior to the experiment. This depth was selected according to Lemos et al (2018). Table 2 presents the amounts of AZEVEDO JUNIOR, M. S. et al…”