updated study guide actual questions and
CORRECT answers
Photon: - CORRECT ANSWER Particles of light
Day light integral (DLI) - CORRECT ANSWER moles of light/sq meter/ day
Max DLI during summer and winter: - CORRECT ANSWER summer: 60 mol.m-2.d-1
winter: 5 mol .m-2.d-1
desirable DLI for plant growth in greenhouse: - CORRECT ANSWER 10-12 mol
phalenopsis and african violets like less at 4-6 mol
How are short days created in greenhouse and what are some precautions? - CORRECT
ANSWER Shade cloth 12-16 hour dark period, however it may cause inconsistent
shadowing which could delay flowering, non uniform flowering, or abnormal flower form.
Light leak- same inconsistencies but also heat delay which can cause delay of crop and
flower abortion.
Plant responses to photoperiod: - CORRECT ANSWER branching, substitute for cold,
photoblastic seed (need light to germinate)
How are long days created in greenhouse? - CORRECT ANSWER Night interuption
lighting
cyclic lighting (on 16 minutes off 24 minutes)
day continuation with lighting (not as good)
What is PAR? - CORRECT ANSWER photosynthetically active radiation