SODEGAURA, Japan—Taro Takagi has helped develop nine breeds of carrots intended to feed millions in Asia—a prime example of how Japan now aims to use new technology to become an agricultural powerhouse.

One of them, dubbed “Amelie,” has extra beta carotene for a brighter orange color that consumers find attractive. Another, “Christine,” yields a uniform cylindrical shape and thrives in colder climates. And “Emma” is resistant to the fungal disease black rot.

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