In the context of plant breeding and genetic engineering, which one of the following statements is correct?
1
To achieve high expression level of a heterologous gene in a transgenic plant a promoter of bacterial origin is often used.
2
F1 progeny derived by crosses between inbred lines with low genetic diversity is more likely to show heterosis.
3
In Agrobacterium mediated plant transformation, always a single copy of the transgene is inserted in the host genome.
4
Qualitative traits are typically characterized by discontinuous phenotypic variation while quantitative traits often generate continuous phenotypic variation.