Statistical Modeling and Optimization of Coag-Flocculation Process of Phosphate Removal from Aqueous Solution Using Ox-Eye Seed (Chrysanthemum leucanthemum) as Coagulant

Excess deposits of phosphorus into surface waters have caused a lot of devastating effects on both human and aquatic lives and, of course, ecosystem disruption. Ox-eye seed (OES), an agricultural biomass, has been explored as a coagulant to remove phosphorus from aqueous solution through coag-flocculation process. The seeds were prepared into a coagulant and a proximate analysis was carried out on the prepared OES. Nephelometric analysis was employed to investigate the effects of settling time, coagulant dosage and pH on phosphate removal efficiency of OES. The process parameters were optimized using Response Surface Methodology. OES’s performance was compared with Alum’s, a conventional coagulant, and the results obtained reveal Alum as having a global minimum of zero turbidity, global optimum values for pH (7.4103) and dosage (301.6501mg/l) but a local optimum of 80min for settling time, while the optimum operating parameters for OES are 7.3740 (global), 500mg/l (local), 80min (local) and 11.2266mg/l (local) for pH, dosage, settling time and turbidity respectively. It is evident that, by increasing settling time and dosage , OES can effectively compete with Alum. The main attribute to effective performance of both OES and Alum is pH. The interactions pH-dosage and pH-settling time are significant. The model accuracy is confirmed by the values of R2 >0.99 and is validated by the closeness of the experimental data to the predictions. Keywords: Phosphorus, wastewater, turbidity, Coagulant, ox-eye, flocculation

Ação de Inseticidas Botânicos sobre a Preferência Alimentar e sobre Posturas de Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) em Milho

O presente trabalho objetivou comparar o efeito de diferentes extratos de origem vegetal na preferência alimentar e na postura da lagarta do cartucho Spodoptera frugiperda (J.E. Smith) em folhas de milho. Extratos aquosos a 10% p/v de Chenopodium ambrosioides (Linnaeus) (Erva de Santa Maria), Corymbia citriodora (Hill & Johnson) (Eucalipto Cheiroso), Chrysanthemum leucanthemum (Linnaeus) (Crisântemo) e Azadirachta indica (A. Juss) (Nim) foram aplicados em discos de folhas de milho e oferecidos às lagartas em testes com e sem chance de escolha. A atratividade das lagartas pelos discos com os extratos não diferiu da testemunha no teste com chance de escolha, porém os extratos de Nim e Crisântemo apresentaram efeito fagodeterrente a S. frugiperda. Nos testes sem chance de escolha, o tratamento que mais repeliu as lagartas foi utilizando extrato de Nim, representando possível alternativa para o controle das lagartas desta espécie. Nenhum dos extratos aquosos das espécies vegetais testadas apresentou efeito ovicida. Action of Botanical Insecticides on the Preference of Food and on Postures of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) in Maize Abstract. This study compares the effect of different extracts of vegetal origin in food preference and posture of the fall armyworm Spodoptera frugiperda (J.E. Smith) in maize leaves. Aqueous extracts 10% w/v of Chenopodium ambrosioides (Linnaeus), Corymbia citriodora (Hill & Johnson), Chrysanthemum leucanthemum (Linnaeus, 1753) and Azadirachta indica (A. Juss) were applied to leaf discs of maize and offered to caterpillars tests with and without choice. The attractiveness of the caterpillars for discs with the extracts did not differ from the control test-choice, but extracts of A. indica and C. leucanthemum showed antifeedant activity to S. frugiperda. In no-choice tests, the treatment was more repelled the larvae using A. indica extract, representing possible alternative for the control of caterpillars of this species. None of the aqueous extracts of the plant species tested showed ovicidal effect.

Soaking curve and effect of temperature on the germination of daisy seeds

The soaking curve and the effect of temperature on the germination of daisy seeds (Chrysanthemum leucanthemum) were characterized in this study. To determine the soaking curve, four samples of 0.5 g of seeds were soaked in germitest paper moistened with distilled water and maintained in germinator at 25ºC. The seeds were weighed in periods of 0, 3, 6, 9, 12, 24, 36, 48, 60, 72, 84 and 96 hours using a precision digital balance of 0.0001 g. A triphasic pattern germination curve was adjusted, allowing the determination of the beginning and duration of the phase II of the germination process. The germination test was carried out with four replications of 50 seeds disposed in "Gerbox" boxes and placed in germinators at the temperatures of 20, 25, 30 or 20-30ºC. A completely randomized experimental design was used with four replications of 50 seeds. The data were submitted to the analysis of variance and the averages were compared by the Tukey test, at 5% of probability. For analysis of accumulated seed germination, regressions were adjusted based on period of experiment. The seeds presented a triphasic pattern of germination and the phases I and II lasted 12 and 48 hours, respectively. The best temperature for the germination of the seeds is 25ºC. The temperature of 30ºC promoted the thermoinhibition of germination and increased the dead and dormant seeds and abnormal seedlings.

Weed survey of spring cereals in New Brunswick

During 1986 and 1987, a weed survey of 187 New Brunswick cereal fields was conducted. A total of 76 species were identified of which 40 were considered agronomically important. About 50% of the species were perennial. Hemp-nettle (Galeopsis tetrahit), quack grass (Agropyron repens), sheep sorrel (Rumex acetosella), ox-eye daisy (Chrysanthemum leucanthemum), corn spurry (Spergula arvensis), and chickweed (Stellaria média) had the highest relative abundance values. Quack grass and hemp-nettle had the highest densities at 8.0 and 7.1 plants m-2, respectively. The highest weed density (103 plants m-2) was found in oats (Avena sativa) grown after a forage crop. The lowest density (24 plants m-2) was found in wheat (Triticum aestivum) grown after potatoes (Solarium tuberosum). Most of the abundant species were tolerant to MCPA, the most commonly used herbicide. Farmers could make major improvements in cereal weed control by choosing a herbicide that would control species tolerant to MCPA or 2,4-D, and using preplant or postharvest weed control to minimize the impact of perennial weeds.

Selecting Species to Develop a Field-grown Wildflower Sod

Twenty-nine annual and perennial wildflower species were evaluated for sod development based on ratings for appearance, root mat density, and stability following undercutting and storage and performance after replanting. Species selection was based on the lack of a large taproot, adaptability to the southeastern climate, flowering period, and potential for surviving root undercutting. Species were seeded in fall and spring, and leaf area and root mass samples were compared. Wildflower sod was undercut at a 5 cm (2 in) depth in March (fall-seeded plots) and May (spring-seeded plots) and then stored on clear plastic for 7 weeks and replanted. Fall-planted species had a higher survival rate than spring-planted species. Species selected for sod development were Achillea millefolium L., Chrysanthemum leucanthemum L., Coreopsis lanceolata L., Coreopsis tinctoria Nutt., Gaillardia aristata Foug., Monarda citriodora Cerv. ex Lag., Rudbeckia hirta L., and Verbena tenuisecta Briq. To reduce damage to aerial growth during harvesting, paclobutrazol, daminozide, and uniconazole were tested on eight greenhouse-grown wildflower species. Uniconazole had limited growth control over Rudbeckia hirta, Monarda citriodora, Coreopsis lanceolata, and Coreopsis tinctoria.