1968-01-01 This publication was intended for use in the training of vegetable specialists and as a reference for vegetable researchers and extension workers.
关键资源2000-12-01 All gardeners and farmers should be plant breeders, says author Carol Deppe. Developing new vegetable varieties doesn't require a specialized education, a lot of land, or even a lot of time. It can be done on any scale. It's enjoyable. It's deeply rewarding. You can get useful new varieties much...