47:	A novel method for growing Arabidopsis thaliana plants hydroponically.

Authors:	Arteca, Richard, N.(A)Arteca, Jeannette, M.(A)
Affiliations:	(A): The Pennsylvania State University
Presenter:	Arteca, Richard N., rna@psu.edu

In this report we will describe the development of a simple system for growing individual Arabidopsis plants hydroponically under environmental conditions which are simple to maintain while maximizing growth and development. The system consists of a Life Raft Float Unit with a 1/2" sponge inserted into its center, this unit is placed into a Magenta GA7 vessel containing Arabidopsis nutrient solution. Plants grown in this experimental system do not require aeration, 125 mE m-2 s-1 supports vigorous plant growth and temperatures between 18 to 24°C were found to be optimal. One quarter to one eighth strength Arabidopsis nutrient solution was found to promote maximal growth while higher levels have an adverse effect. Plants grown under these conditions exhibit physiological factors such as time to flowering and overall appearance similar to those grown in soil. The low maintenance method developed minimizes shortcomings found with other hydroponic systems previously used to grow Arabidopsis plants such as loss of root material, excess manipulation, algae formation, inability to readily observe root growth, eliminates the need for aeration and others, while maximizing overall biomass production. Advantages of this system include easy manipulation of specific growth conditions or nutrients, observation of the root systems without sacrificing the plant, application of phytohormones or chemicals to the roots and ability to screen for new mutant plants under controlled growth conditions. Changes in root growth at various stages during the life cycle of hydroponically grown plants will also be discussed.