Plants in this stock have cotyledons, leaves, stems, and developing pods that are a light yellow-green color that contrasts with the normal green of the standard stock; the purple pigment anthocyanin is expressed in the stems, leaves, and bud tips. The presence of strong anthocyanin expression the yellow-green color is less pronounced.

7 days old	16 days old

Tips for the Grower
Basic experience with growing Fast Plants is recommended prior to using this stock.

Notes on Genetics
The yellow-green phenotype occurred naturally as a yellow seedling in a base population. This stock was initially developed by selection on increasing the clarity of expression of the yellow-green color. The genotype for this stock is ygr/ygr. The ygr allele segregates as a single-gene recessive. This stock appears to be more self-compatible than other stocks.

Dihybrid - Use the yellow-green leaf stock in a cross with non-purple stem plants. What do the offspring look like? If these offspring are crossed, do students find the predicted 9:3:3:1 segregation ratio in the F2 generation?

Monohybrid - Cross yellow-green leaf plants with purple stem plants. What do the offspring look like? Are there any plants in the F1 generation that express the yellow-green leaf phenotype?

Plant reproduction - Are plants in this stock are more self-compatible than other stocks?

Physiology - How would students investigate whether the yellow-green leaf phenotype is due to a lower level of chlorophyll in the plants? Does yellow-green beat green? Test to see whether the genetic load associated with the yellow-green color has any developmental effects in comparison to the standard stock.

Ecology - Examine any positive and/or negative adaptive attributes associated with this genotype. Does high nutritional or light stress drown out the yellow-green by increasing the intensity of the anthocyanin expression?

C. O. Chichester, The Chemistry of Plant Pigments, Academic Press (New York), 1972.

T. W. Goodwin, ed., Chemistry and Biochemistry of Plant Pigments, Academic Press (New York), 1976.

G. Mazza, Anthocyanins in Fruits Vegetables and Grains, CRC Press (Boca Raton).