Greenhouse and field studies examined the effect of flower or seedhead removal on leaf senescence and associated changes in sunflower (Helianthus annuus L.) plants. At intervals during seed development, selected leaves (leaves 6 through 8 from the top in the greenhouse and leaf 7 from the top in the field) were harvested and analyzed for chlorophyll, specific leaf weight, N, P, soluble protein,...

We are living in a great Greenhouse: our planet, the Earth. This sustainable system is almost closed, except the radiative energy received from the Sun. Understanding and respecting its principles is the only guaranty for a safe future of our species. The Greenhouse effect is a process by which a part of the incident solar energy is trapped by the lower atmosphere due to the action of some atmo...

susceptibility of eggs, nymphs and adults of greenhouse whitefly (trialeurodes vaporariorum westwood) and adults of green peach aphid (myzus persicae sulzer) to pirimicarb (pirimor®) and citowett oil alone vs. in combination was evaluated under greenhouse conditions. the glass vial and leaf dipping methods were employed for bioassay of adults vs. the immature stages (egg, nymph and pupa) of gre...

Within a simplified atmospheric model the greenhouse effect is treated by analytical methods starting from physical first principles. The influence of solar radiation, absorption cross sections of the greenhouse molecules, and cloud formation on the earth’s temperature is shown and discussed explicitly by mathematical formulae in contrast to the climate simulations. The application of our analy...

Integrated assessment models of climate change typically analyze the case of a doubling of atmospheric CO2.over the pre-industrial concentration of about 270 ppm. This is a serious shortcoming since under a scenario in which all accessible fossil fuels are burned, atmospheric CO2 concentrations will more than quadruple. We introduce an analytical framework that endogenously accounts for potenti...

This paper uses a primitive general equilibrium (GE) model to examine variation in carbon dioxide (CO2) produced by human activity. This model consists of two goods; food and energy. Food is produced using labor and energy, while energy is produced using labor. It is assumed that food output decreases as CO2 increases. The representative household has a utility function with food and energy as ...