Texas FFA Nursery Landscape Practice Exam

In the plant name Ilex x merserveae 'Blue Princess', what does "x" signify?

1. It is patented

2. It is a hybrid

3. It is a tetraploid

4. Its origin is unknown

The correct answer is: It is a hybrid

In the name Ilex x merserveae 'Blue Princess', the "x" signifies that the plant is a hybrid. This convention is used in plant nomenclature to indicate that the species has resulted from the crossbreeding of two different species or cultivars within the same genus. Hybrids are often created to enhance specific traits such as disease resistance, growth habit, or flowering characteristics. In this instance, Ilex x merserveae is a hybrid holly, derived from crossing two different species in the Ilex genus. The other choices, while they cover areas in botanical nomenclature or plant breeding, do not pertain to the use of "x." A patent refers to legal protections for new cultivars, a tetraploid indicates a specific number of chromosome sets that doesn’t directly relate to the designation of a hybrid, and stating that the origin is unknown doesn't apply, as hybrid status is explicitly denoted through the "x."