82 research outputs found
Photocontrol of productivity and stem elongation of three Rosa x hybrida L. cultivars under photoselective films
Se evaluaron los cambios en la radiación
transmitida a través de films fotoselectivos (FS)
fluorescentes y el impacto de estos cambios sobre
la producción de tres cultivares de rosa para corte
Fuego Negro, Maroussia y Anna. Se observó que
los FS nuevos o expuestos a la radiación solar
vs. noFS disminuyen la transmisión de radiación
azul (A) (-28,4 a -32,9%, respectivamente),
incrementan el R produciendo una relación R:RL
mayor (+3,6%), si bien transmiten algo menos
de radiación fotosintéticamente activa que los
noFS nuevos. El número de rosas producidas
fue significativamente mayor bajo el FS vs. noFS
en los tres cv (+24, +32 y +36% en Anna, Fuego
Negro y Maroussia, respectivamente), con un peso
fresco y seco (PF y PS) significativamente mayor
y tallos florales más largos en Anna y Maroussia
(50,69 y 43,91 cm vs. 38,91 y 40,04 cm en
invierno y primavera, respectivamente), y
pimpollos significativamente más largos y de
mayor PF y PS en los tres cv. Mayor relación
R:RL y menor UV-A y A en la radiación transmitida
por films FS aumentaron la cantidad y calidad
de determinados cultivares de rosas mostrando
una alternativa a los reguladores químicos
de crecimiento.This research evaluate changes in the
radiation transmitted through a photoselective,
fluorescent polyethylene film (PS), and the
impact of these changes on the production of
three cut rose cultivars, Fuego Negro, Maroussia
and Anna. PS vs. nonPS films, new or exposed
to solar radiation, decreased transmission of blue
radiation (-28.4 to -32.9%, PS-new and PS-old,
respectively), increased red radiation, resulting
in a R:FR ratio greater 3.6% than for nonPS,
although, PS-new and PS-old films transmitted
a smaller percentage of PAR than non-PS-new
(-16.6 and -22.4%, respectively). The number of
roses harvested was significantly higher under
PS vs. nonPS film for the three cultivars (+24,
+32 and +36% flowers m-2, in Anna, Fuego Negro
and Maroussia, respectively), with significantly
higher fresh weight (FW) and dry weight (DW),
longer floral stems in Anna and Maroussia (50.69
and 43.91 cm vs. 38.91 and 40.04 in winter
and spring, respectively) and buds significantly
longer and higher FW and DW in the three cv.
Higher R:FR and lower UV-A and B radiation of
PS greenhouse covers increased quantity and
quality of some of these rose cultivars featuring
an alternative to chemical growth regulators.Fil: Mascarini, Libertad.
Universidad de Buenos Aires. Facultad de AgronomíaFil: Lorenzo, Gabriel A..
Universidad de Buenos Aires. Facultad de AgronomíaFil: Burgos, Marcelo L..
Universidad de Buenos Aires. Facultad de Agronomí
Fotocontrol de la productividad y elongación de tallos de tres cultivares de Rosa x hybrida L. bajo cubiertas de polietileno fotoselectivas
This research evaluate changes in the radiation transmitted through a photoselective, fluorescent polyethylene film (PS), and the impact of these changes on the production of three cut rose cultivars, Fuego Negro, Maroussia and Anna. PS vs. nonPS films, new or exposed to solar radiation, decreased transmission of blue radiation (-28.4 to -32.9%, PS-new and PS-old, respectively), increased red radiation, resulting in a R:FR ratio greater 3.6% than for nonPS, although, PS-new and PS-old films transmitted a smaller percentage of PAR than non-PS-new (-16.6 and -22.4%, respectively). The number of roses harvested was significantly higher under PS vs. nonPS film for the three cultivars (+24, +32 and +36% flowers m-2, in Anna, Fuego Negro and Maroussia, respectively), with significantly higher fresh weight (FW) and dry weight (DW), longer floral stems in Anna and Maroussia (50.69 and 43.91 cm vs. 38.91 and 40.04 in winter and spring, respectively) and buds significantly longer and higher FW and DW in the three cv. Higher R:FR and lower UV-A and B radiation of PS greenhouse covers increased quantity and quality of some of these rose cultivars featuring an alternative to chemical growth regulators.Se evaluaron los cambios en la radiación transmitida a través de films fotoselectivos (FS) fluorescentes y el impacto de estos cambios sobre la producción de tres cultivares de rosa para corte Fuego Negro, Maroussia y Anna. Se observó que los FS nuevos o expuestos a la radiación solar vs. noFS disminuyen la transmisión de radiación azul (A) (-28,4 a -32,9%, respectivamente), incrementan el R produciendo una relación R:RL mayor (+3,6%), si bien transmiten algo menos de radiación fotosintéticamente activa que los noFS nuevos. El número de rosas producidas fue significativamente mayor bajo el FS vs. noFS en los tres cv (+24, +32 y +36% en Anna, Fuego Negro y Maroussia, respectivamente), con un peso fresco y seco (PF y PS) significativamente mayor y tallos florales más largos en Anna y Maroussia (50,69 y 43,91 cm vs. 38,91 y 40,04 cm en invierno y primavera, respectivamente), y pimpollos significativamente más largos y de mayor PF y PS en los tres cv. Mayor relación R:RL y menor UV-A y A en la radiación transmitida por films FS aumentaron la cantidad y calidad de determinados cultivares de rosas mostrando una alternativa a los reguladores químicos de crecimiento
Presence of eggs of Toxocara spp. and hookworms in a student environment in Rio Grande do Sul, Brazil
Emergent and re-emergent parasites in HIV-infected children: immunological and socio-environmental conditions that are involved in the transmission of Giardia spp. and Cryptosporidium spp.
Reductions in the Prevalence and Incidence of Geohelminth Infections following a City-wide Sanitation Program in a Brazilian Urban Centre
In the city of Salvador, a large urban centre in Northeast Brazil, a city-wide sanitation intervention started in 1997, aiming to improve the sewerage coverage of households from 26% to 80%. Our aim was to study the impact of the intervention on the prevalence and incidence of geohelminths in the school-aged population. The longitudinal study comprised two cohorts: from the beginning of 1997 to 1998, where data was collected before the intervention, and at the end of 2003 to 2004, after the intervention. Copro-parasitological examinations were carried out on every individual from both cohorts, at the start and nine months later. Demographic, socio-economic, and environmental data were collected using semi-structured questionnaires. The variables utilized to demonstrate the effects of intervention, when utilized together in a multivariate model, accounted for a 100% observed reduction in the prevalence ratio (PR) and incidence ratio (IR). As well as proving that the variables associated with the effect of the program intervention were mediators in this reduction, the reduction in the PR and IR between these periods demonstrated that modifications to the urban environment, particularly those associated with sanitary sewage systems, affected the health of the population, significantly reducing the prevalence of geohelminths
Casos de leishmaniose tegumentar americana por Leishmania (viannia) braziliensis nos municípios de cosmópolis e Indaiatuba - região de Campinas, estado de São Paulo, Brasil
Spatiotemporal distribution and population at risk of soil-transmitted helminth infections following an eight-year school-based deworming programme in Burundi, 2007–2014
Epidemiologists working together with anthropologists: lessons from a study to evaluate the epidemiological impact of a city-wide sanitation program
- …