Plants of the petite stock have all parts reduced in size in proportion to height, giving the petite appearance in comparison with the standard stock. The plants also have a more intense green color than the standard. Petite plants are capable of growing in a reduced volume and growing space than the standard stock.

7 days old	16 days old

Tips for the Grower
Moderate experience with growing Fast Plants is recommended prior to using this stock. Plants of the petite stock may be negatively influenced by environmental stresses; they have a lower threshold than standard Fast Plants for variation in the growing environment. It is advisable to sow extra seeds per pot and then thin to the desired number of plants at about Day 4 of the life cycle.

Petite size permits dense planting and accommodates transportation of potting systems. More than one plant will produce seed in a soil volume of 7 cc.

Notes on Genetics
The petite phenotype is conditioned by a single gene mutation. When first discovered, the genotype was very deleterious, with the gene involved having a very broad effect; for example, the plants had brittle stems due to a lower amount of fiber in the tissue. By outcrossing to the standard stock over many generations, the petite genotype has been moved into a more favorable genetic background and its more negative effects have been reduced. The petite trait is expressed genotypically as dwf1/dwf1.

The petite stock has been used widely in the genetic development of other stocks, including AstroPlants, a stock used in Space Shuttle experiments by plant scientists. The selection process for this stock was nicknamed "5-10-15": selection was for a high proportion of plants that produced 5 seed pods, grew to less than 10 centimeters in height, and flowered in 15 days.

Ideas for Investigations
Basic plant science - If you have restricted space for your growing systems, use this stock to study all aspects of plant growth and development, reproduction, and genetics. What are the effects of plant density on seed production?

Physiology - Investigate whether the petite stock responds to plant growth regulators like gibberellic acid. Are plants of this stock smaller because each cell is smaller? Would smaller cells contain the same number of chloroplasts in the reduced space, thus giving the plant its darker green color? Is the photosynthetic rate different for petite plants?

Space and gravitational science - Explore ideas about why the very petite AstroPlant stock was chosen for experiments in space. Try some experiments that investigate plant responses to gravity. What would happen in the low-gravity environment of space?