What determines the capital-labor ratio in production of commodities?

Question

What determines the capital-labor ratio in production of commodities?

Answer 1

Technological progress is an important determinant.

Another important question is why the capital-labor ratio for the same commodity is different in different countries (farming of the same crop is more labor-intensive in China then in the U.S.). In the presence of perfect capital markets this should not happen (see link below).