Most foods are an acquired taste, Baranowski says. There's a good amount of neophobia, fear of new foods, in the early years. If you provide a variety of foods at different times, and insist they take just one bite, you can overcome that. There's some very nice research that shows that repeated exposure with a bite increases the likelihood that children will like the food over time, even broccoli. Also, mom and dad need to set a good example by not shunning fruits and vegetables themselves.
Kids are bright.
Struggles ensue when parents are authoritarian, demanding that kids eat the green stuff on the dinner plate. Lots of adults won't even do that. You need to identify things that relevant to children and emphasize them. Another rising star is kiwi fruit. The nice thing about giving kids reasons is that kids tend to internalize the message.