Plant Physiology (Biology 327)  - Dr. Stephen G. Saupe;  College of St. Benedict/ St. John's University;  Biology Department; Collegeville, MN  56321; (320) 363 - 2782; (320) 363 - 3202, fax;    ssaupe@csbsju.edu

Early Seedling Growth & Development

Objectives:  The purpose of this lab experience is to provide an opportunity to:

1. observe and compare hypogaeous and epigaeous seed germination
2. compare monocot and eudicot seedlings

Exercise 1.  Hypogaeous vs. Epigaeous Germination
    When some seeds germinate the cotyledons remain underground (termed epigaeous) while in other species the cotyledons are pushed above the ground (hypogaeous).  In this examine the germination of three species- maize, sunflower, and pea - and describe whether the seedlings exhibit the epigaeous or hypogaeous pattern of germination.

Method:  In a pot containing pre-moistened Jiffy-Mix, place three seeds each of the three species.  Moisten the medium, label with your name and date, cover with plastic wrap, and place the pot in the light.  After the seeds germinate, sketch or photograph the seedlings.  

Assignment:  Prepare a sketch or photograph comparing the three seedlings.  Label each.  Describe the differences between the three species.  Be sure to indicate which are hypogaeous and epigaeous and the functional (physiological) significance of these differences.

Exercise 2.  Grass vs. Eudicot Seedlings Early Development
    In this exercise we will compare the early growth of maize or oats (grasses) and radish.  In each of two pots containing pre-moistened Jiffy Mix plant three seeds each of corn (or oats) and radish.  Moisten the medium, label with your name and date, cover with plastic wrap.  After several days, sketch or photograph the seedlings.  Describe the differences.  Consider:  how do the seedlings protect the root and shoot meristems?  How do the seedlings obtain nutrients before they become photosynthetically active?  What is the function of the cotyledon? 

Last updated:  01/07/2009     � Copyright  by SG Saupe