CRESCIMENTO E FITOMASSA DE BATATA-DOCE IRRIGADA COM ÁGUA RESIDUÁRIA TRATADA

CRESCIMENTO E FITOMASSA DE BATATA-DOCE IRRIGADA COM ÁGUA RESIDUÁRIA TRATADA RAUCHA CAROLINA DE OLIVEIRA1; PATRÍCIA FERREIRA DA SILVA2; RIGOBERTO MOREIRA DE MATOS3; JOSÉ DANTAS NETO4; LUCIANO MARCELO FALLÉ SABOYA5 E MARIA SALLYDELÂNDIA SOBRAL DE FARIAS6 1Mestranda em Engenharia Agrícola, Rua Aprígio Veloso, 882 - Universitário, Campina Grande - PB, Brasil, 58428-830, e-mail: [email protected] 2Pós- doutoranda em Engenharia e Gestão dos Recursos Naturais, Rua Aprígio Veloso, 882 - Universitário, Campina Grande - PB, Brasil, 58428-830, e-mail: [email protected] 3Doutor em Engenharia Agrícola, Rua Aprígio Veloso, 882 - Universitário, Campina Grande - PB, Brasil, 58428-830, e-mail: [email protected] 4Professor Doutor, Universidade Federal de Campina Grande, Unidade Acadêmica de Engenharia Agrícola, Rua Aprígio Veloso, 882 - Universitário, Campina Grande - PB, Brasil, 58428-830, e-mail: [email protected] 5Professor Doutor, Universidade Federal de Campina Grande, Unidade Acadêmica de Engenharia Agrícola, Rua Aprígio Veloso, 882 - Universitário, Campina Grande - PB, Brasil, 58428-830, e-mail: [email protected] 6Professora Doutora, Universidade Federal de Campina Grande, Unidade Acadêmica de Engenharia Agrícola, Rua Aprígio Veloso, 882 - Universitário, Campina Grande - PB, Brasil, 58428-830, e-mail: [email protected] 1 RESUMO A utilização de água residuária tratada na irrigação de culturas agrícolas é apontada como uma alternativa para atenuar o problema da escassez hídrica. Assim, objetivou-se com o presente trabalho avaliar o crescimento e fitomassa de batata-doce irrigada com água residuária tratada. A pesquisa foi desenvolvida em ambiente protegido pertencente à unidade acadêmica de engenharia agrícola da Universidade Federal de Campina Grande, em delineamento de blocos casualizados em arranjo fatorial 3x2, com cinco repetições. Os fatores de variação consistiram em três qualidades de água (T1 = água de cisterna; T2 = água tratada por wetland e T3 = água tratada por UASB+wetland), e duas cultivares de batata-doce (Campina e Granfina). Avaliou-se ao final do ciclo de cultivo o número de folhas (NF), número de ramas (NR), área foliar (AF), diâmetro do caule (DC), fitomassa fresca de folhas (FFF), fitomassa fresca de ramas (FFR), fitomassa seca de folhas (FSF), fitomassa seca de ramas (FSR). Os resultados obtidos demonstram que as variáveis (NF), (NR), (AF), (FFF), (FSF) e (FSR) foram influenciadas de forma significativa pelas cultivares. A água residuária tratada na irrigação de batata-doce pode ser utilizada sem que haja perdas das características de crescimento e fitomassa. Palavras-Chave: Ipomoea batatas L., reúso, gotejamento, efluente. OLIVEIRA, R. C.; SILVA, P. F.; MATOS, R. M.; DANTAS NETO, J.; SABOYA; L. M. F.; FARIAS, M. S. S. GROWTH AND PHYTOMASS OF SWEET POTATO IRRIGATED WITH TREATED WASTEWATER 2 ABSTRACT The use of treated wastewater in the irrigation of agricultural crops is indicated as an alternative to mitigate the problem of water scarcity. Thus, this study aimed to evaluate the growth and phytomass of sweet potatoes irrigated with treated wastewater. The study was conducted in a greenhouse belonging to the academic unit of agricultural engineering at the Federal University of Campina Grande, in a randomized block design and 3x2 factorial scheme, with five replications. The factors consisted of three water qualities (T1 = water from a cistern; T2 = water treated by wetland and T3 = water treated by UASB + wetland), and two sweet potato cultivars (Campina and Granfina). At the end of the cultivation cycle, the number of leaves (NF), number of branches (NR), leaf area (AF), stem diameter (DC), fresh leaf phytomass (FFF), fresh branch phytomass (FFR), dry leaf phytomass (FSF) and dry branch phytomass (FSR) were evaluated. The results obtained show that the variables (NF), (NR), (AF), (FFF), (FSF) and (FSR) were significantly influenced by the cultivars. Wastewater treated for irrigation of sweet potatoes can be used without loss of growth and phytomass characteristics. Keywords: Ipomoea batatas L., reuse, drip irrigation, effluent.

A Closed-capture Irrigation Effluent System For Monitoring Large Container Leachate

Irrigation management is essential in producing quality woody ornamentals and minimizing off-site runoff. The closed-capture effluent device provided an inexpensive method of monitoring effluent in large containers throughout the year with minimal effort. Daily irrigation requirements for `Little Gem' southern magnolia (Magnolia grandifolia) were established throughout an entire growing season. The maximum daily water requirement was approximately 3 gal (11.4 L).

160 A Closed-capture Irrigation Effluent Apparatus for Large Nursery Containers

A closed capture irrigation apparatus was designed and constructed for the purpose of monitoring irrigation effluent volume and nutrient analysis from 121-L redwood tree boxes. Measurements were taken monthly from Apr. 1997 to Oct. 1998. Tree boxes were filled with either a 3 pine bark: 1 sand: 1 peat or 3 pine bark: 1 soil media and planted with `Little Gem' magnolia [Magnolia grandiflora (L.) `Little Gem'] or Southern live oak (Quercus virginiana var. virginiana Mill.). In-line, pressure-compensated drip emitters provided irrigation water at the rate of 2 L/h. Daily irrigation volume ranged from 8 L in the fall and spring to 16 L during the summer months. The collection apparatus was constructed from 1-cm angle iron, neoprene rubber, a small drain assembly, and a 22-L plastic container. A square metal frame (43 × 43 cm) was supported by 31-cm legs and draped by a neoprene rubber mat with a drain assembly installed in the center. The drain was positioned into the plastic container creating a closed system to reduce effluent evaporation. The container capacity was adequate to store at least 24 h of collected effluent. This apparatus proved to be an efficient method of collecting irrigation effluent from large containers.

Effects of Ground Cover and Formulation on Herbicides in Runoff Water from Miniature Nursery Sites

Granules of isoxaben plus trifluralin and liquid applications of isoxaben plus oryzalin were applied to miniature nursery plots covered with plastic, woven landscape fabric, or gravel with no cover. Herbicide concentrations were monitored in runoff water over a 30 d period. Runoff losses of isoxaben from the sprayable formulation applied to gravel were 5% greater than from plastic and 4% greater than losses from fabric in 1992. Similarly, oryzalin losses from the sprayable formulation applied to gravel were 7% greater than losses from plastic and 4% greater than losses from the fabric ground cover. In contrast, loss of isoxaben from the granular formulation applied to plastic was 7% greater than loss from gravel in 1993. Isoxaben losses from the granular formulation applied to fabric were intermediate. Trifluralin losses from the granular formulation applied to plastic and fabric were both 3% greater than losses from gravel. In addition, isoxaben losses from the granular formulation were 11 and 10% greater than loss from the sprayable formulation applied to the plastic and fabric-covered plots, respectively. Isoxaben losses from the sprayable formulation applied to gravel were 11% greater than losses from the granular formulation. In an experiment to determine herbicide release patterns and the effect of light on residues from the granular formulation of isoxaben and trifluralin in irrigation effluent, water was monitored for 36 d. Approximately 20% of the applied isoxaben and 7% of the applied trifluralin was detected in irrigation water during the 36 d period. These studies indicate that runoff losses and the ultimate fate of isoxaben, oryzalin, and trifluralin applied in nursery settings depend on factors including ground cover composition, herbicide formulation, and photochemical degradation.

Treatment of Irrigation Effluent Water to Reduce Nitrogenous Contaminants and Plant Pathogens

The contamination of surface and subterranean drinking water supplies with nitrogen-laden agricultural wastewater is a problem of increasing concern in the U.S. and Israel. Through this research, we found that bacteria could utilize common organic wastes (e.g. paper, straw, cotton) as carbon sources under anaerobic conditions, and reduce nitrate concentrations in wastewater to safe levels. Two species of bacteria, Cellulomonas uda and a Comamonas sp., were required for dentitrification. Celulomonas uda degraded cellulose and reduced nitrate to nitrite. In addition, it excreted soluble organic carbon needed as a food source by the Comamonas sp. for completion of denitrification. We also found that recirculated irrigation water contains substantial amounts of fungal inoculum, and that irrigating healthy plants with such water leads to significant levels of root infection. Water can be disinfected with UV, but our experiments showed that Hg-vapor lamps do not possess sufficient energy to kill spores in wastewater containing dissolved organics. Excimer lasers and Xenon flashlamps do possess the needed power levels, but only the laser had a high enough repetition rate to reliably treat large volumes of water. Ozone was highly efficacious, but it's use as a water treatment is probably best suited to moderate or low volume irrigation systems. This research provides critical data needed for the design of effective water denitrification and/or pathogen disinfection systems for different growing operations.