Phenotype, Genotype and Environment

The fall semester class encountered a problem when they scored the leaf color phenotypes. The yellow leaf trait was always easy to identify but in many trays the pale green and dark green trait were difficult to distinguish. Because of sunny warm September days, the greenhouse was very hot and the plants were under stress. This limited leaf expansion, making it difficult to quantify the amount of green pigment in the leaf with the naked eye. The best the class could do was group the dark green and pale green plants into the same phenotype group, leaving the yellow in their own group. Environment had influenced the ability to distinguish the two proposed genotypes. However, it is possible to use the data to determine how the leaf color and leaf number traits are inherited together.