The contrast in how the village children (line 11) and the man (line 13) respond to the two trees most clearly serves to underline
Responses

the children’
the children’s enjoyment of Don Miguel’s fruit
the children’s enjoyment of Don Miguel’s fruit

the man’s dislike of children
the man’s dislike of children

the man’s lack of imagination
the man’s lack of imagination

the man’s knowledge of horticulture