In Hawaii we have so many diseases you have to find the plants that survive and taste good. Sometimes you can find one but not the other.
For plants to survive in the ground, they really need nematode resistance, because of humidity you need to find cultivars with mildew resistance (shiny leaves), and resistance to fusarium (3 strains would be excellent) verticillium wilt and resistance to the common virus TMV, CMV, and if you grow corn, maize mosaic virus. Papaya ringspot virus, if you live in a place with a lot of squash and papaya, and banana bunchy top.
It helps to grow plants in sterile potting mix if they are prone to root issues like nematodes, pythium and phythoptora root rots, and especially if your soil does not drain well.
Plants with shiny leaves have fewer fungal issues, but plants with gray or hairy leaves have a hard time surviving when it rains for a week. It helps in high humidity to help susceptible plants by spraying them with a horticultural oil to help them wick off the water droplets and to start a fungicide program when the humid weather conditions are ripe.
The cherry tomatoes get targeted too, but they are more productive than the large tomatoes.
The UH cultivars are very disease resistant, but the tomatoes have tough skins and I don't like that. Most of the UH tomatoes were developed over 20 years ago so they do not have resistance to the newer viruses like tomato yellow leaf curl. Of all of the UH tomatoes Kewalo and Healani are probably the best.
I also like Heatwave II as it was the only tomato that kept producing in 90 degree weather. It was not the greatest tasting but better than anything else available.
The UH does have very good corn UH #9 and #10 are sweet, tight husk, and can be grown all year. They do have a hard kernel. I don't like that part because it gets stuck between my teeth.
Poamoho, Manoa and Hawaiian wonder beans are good. They are similar to Kentucky wonder. Poamoho is a flat green bean that is nematode and rust resistant. The others are nematode resistant but not necessarily rust resistant.
Kaala bell. What can I say, it is a disease resistant plant but produces a bell pepper that is 1/3 the size of a Cal Wonder.