Why do vegetatively propagated plants tend to be more vulnerable to diseases than sexually reproduced plants?
Vegetatively propagated plants reproduce asexually and involve only one parent. Because of this, the key point of this reproduction method is that it produces offspring that are genetically identical to the parent plant.
Since all the plants in a vegetatively propagated crop are genetically identical, they lack genetic diversity. If a disease infects one plant, it can easily infect the entire population of identical plants. In contrast, sexually reproduced plants have genetic variations, making them less uniformly vulnerable to a single disease.
Explanation
The textbook context emphasizes that vegetative propagation involves only one parent and produces genetically identical individuals. This genetic uniformity is the core reason for their vulnerability; if a pathogen can infect one plant, all identical offspring are susceptible. The context also notes that tissue culture from shoot tips is used to eliminate virus-infected plants, highlighting the inherent disease risk in vegetative propagation that requires such intervention.
Solution Steps
Step 1: Identify that vegetative propagation involves only one parent and produces genetically identical individuals.
Step 2: Conclude that genetic uniformity makes the entire population susceptible to the same diseases, increasing overall vulnerability.