Author Archives: Erik Runkle

About Erik Runkle

Erik Runkle is associate professor at Michigan State University. You can eMail him at runkleer@msu.edu.

Using ABA To Reduce Water Loss In Chrysanthemum & Aster

Greenhouse crop production often employs the use of plant hormones and growth-regulating chemicals to control growth such as plant height, rooting and flowering. Abscisic acid (ABA) is a natural plant hormone produced in roots in response to drought conditions. ABA is moved to the leaves, where it stimulates the closure of stomata, reduces water loss

Ready Research Results: Daily Light Integral & Flowering Of Annuals

Daily light integral (DLI) refers to the cumulative amount of photosynthetic light that is received in one day. Determination of the DLI requires that light is measured repeatedly over time and then integrated. It cannot be determined instantaneously. DLI is expressed as moles of photons of light received per square meter per day (mol∙m¯²∙d¯¹), or

Energy-Efficient Annuals: Pentas & Verbena

Efficient production of bedding plants requires information on how temperature, photoperiod, and daily light integral (DLI) influence crop timing and flowering characteristics. During the past several years at Michigan State University (MSU), we have performed experiments with seed-propagated annuals to quantify how temperature and DLI influence flowering time and plant quality. In the 12th and

Energy-Efficient Annuals: Angelonia & Browallia

Scheduling annual bedding plants in flower for specific market dates is of increasing importance to greenhouse growers. Plants not in flower when planned or in flower too early can create greenhouse space challenges, delay shipping and reduce plant quality. During the past several years at Michigan State University (MSU), we have performed experiments with seed

Energy-Efficient Annuals: Dahlia & Osteospermum

Producing spring bedding plants in an energy-efficient manner requires information on how crops respond to average daily temperature and daily light integral (DLI) so bedding plants can be more precisely scheduled. At Michigan State University (MSU), we have performed experiments with numerous seed-propagated annuals to quantify how these environmental factors influence flowering time and plant

Energy-Efficient Annuals: Rudbeckia & Viola

Scheduling bedding plants in flower for exact market dates is challenging considering the diversity of crops produced. Rising energy costs and shrinking profit margins have made it important to improve scheduling and efficiency of crop production. At Michigan State University (MSU), we have performed experiments with many seed propagated annuals to quantify how temperature and

Energy-Efficient Annuals: Geraniums And Zinnias

Most bedding plants are produced in heated greenhouses from January through May, when high energy inputs can be required to maintain a desirable temperature. With shrinking profit margins and volatile energy prices, scheduling crops in an energy-efficient manner is increasingly desirable. At Michigan State University (MSU), we have performed experiments with many seed-propagated annuals to