Beatrice grows maize (Zea mays) in a large agricultural field.
Explain how each of the following factors could affect the growth and final yield of her maize crop:
(i) Specific alleles inherited from the parental crop lines.
(ii) Bacterial species present in the soil.
Beatrice actively manages wild plants growing between the rows of maize.
(i) Suggest what is meant by the term 'weed' in this agricultural context.
(ii) Explain why removing these weeds from the crop field would maximize the growth and yield of the maize.
(iii) State one chemical or ecological method Beatrice could use to control the growth of weeds.