Minimal models of curves of genus 2 and homomorphisms of abelian varieties defined over a field of finite characteristic

In this article, we prove a finiteness theorem for isogenous abelian varieties of dimension 2 defined over a field of algebraic functions of one variable whose characteristic $\ne2$. By means of this result, we prove Tate's conjecture on homomorphisms of abelian varieties of dimension 1 defined over the same field.