I was looking for words that begin with the letter "x" to fill in this post. Thanks to the Internet, it isn't as difficult as you would think. I found a word on The Phrontistery: "xanthospermous." It means "having yellow seeds." And then it occurred to me that I couldn't think of any plants that have yellow seeds. I had to do more research. I found a lot of information about plants with yellow seeds being dominant. And then there was a bunch of stuff form biology that I vaguely remember from 20 years ago.
Mustard seeds are often yellow or white.
Some varieties of ferns will drop yellow seeds.
A heterozygous pea plants will drop yellow seeds.
Do you know of any other xanthospermous plants?