Author：Erik S. Runkle

Department of Horticulture, Michigan State University, East Lansing, MI 48824, USA
Author for correspondence: runkleer@msu.edu

Abstrct：

    Photoperiod, the photosynthetic daily light integral (DLI), and mean daily temperature are three environmental parameters that have the largest effects on plant growth and development. During commercial production of floriculture crops, one or more of these factors is often manipulated so that crops are marketable when desired. In temperate climates (e.g., >35 ˚N latitude), high-intensity (photosynthetic or supplemental) lighting is provided to increase growth and accelerate flowering when ambient light conditions are low. In addition, growers provide low-intensity (photoperiodic) lighting to deliver long days, which accelerates flowering of long-day plants. Finally, growers often control temperature, which influences cropping time and plant quality attributes. Since a substantial amount of energy is used to heat greenhouses located in cold climates, growers need to optimize temperature so that energy costs are minimized on a per-crop basis. This paper describes how light and temperature influence growth and flowering of floriculture crops and presents information to improve the energy efficiency of greenhouse crop production based heavily on recent research performed at Michigan State University.

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