Rosemary plants (Salvia rosmarinus) are often propagated by taking cuttings to produce new, cloned plants.
Describe how to clone a rosemary plant by taking a stem cutting.
A grower wanted to find out whether rooting hormone solution X or solution Y is more effective. The grower treated one cutting with solution X and one cutting with solution Y before planting them in identical compost. Both cuttings were kept under the same light intensity and temperature.
After 4 weeks, the grower measured the total length of roots produced by each cutting:
The grower concluded that solution X is more effective. A student commented that, although the experiment was valid, the single-replicate design means the results do not strongly support this conclusion.
Describe and explain how the grower could improve this investigation to have more confidence in the conclusion.
State three advantages of vegetative propagation (cloning) compared to growing plants from seeds in commercial horticulture.
