Question

Phylloxera, a pest related to aphids, destroyed many vineyards in France at the end of the 19th century. The vineyards were restored by grafting old vines on American root stocks, which were resistant to the pest. Using this situation, explain how biodiversity loss can impact crop diversity.

a. Loss of wild species would result in inbreeding depression, as crop varieties must be bred with wild species to remain viable.
b. Loss of biodiversity reduces large-scale monocultures but reinforces genetic homogeneity contributing in the loss of crop diversity.
c. Loss of wild species would result in an increase of intraspecific diversity within the different crop varieties, but decrease in interspecific crop diversity.
d. Loss of wild species would reduce the genetic variations as genes from wild relatives are brought into crop varieties to add valued characteristics to crops.

Answer 1

Loss of wild species related to a crop can result in the loss of potential in crop improvement and decreased crop diversity. The correct answer is option a.

Step-by-step explanation:

The phylloxera crisis in French vineyards highlights how the loss of biodiversity can negatively impact crop diversity. When the phylloxera, an aphid-like pest, destroyed many vineyards, the solution was to graft European vine species onto resistant American rootstocks.

Through this example, we see that wild species play a critical role in maintaining the genetic variety necessary for breeding resilient crop varieties. The loss of wild species can lead to a reduction in genetic variation and an increased risk of inbreeding depression.

Where a lack of genetic diversity within a population can result in decreased fitness and survival. Additionally, reliance on monocultures can reinforce genetic homogeneity, further contributing to the loss of crop diversity and making crops more susceptible to pests and diseases.