Sunflower (Helianthus annuus L.) is one of four main oil crops in the world and its hybrid production depends on three lines (sterile line, maintainer line and restoring line).是什么意思_Sunflower (Helianthus annuus L.) is one of four main oil crops in the world and its hybrid production depends on three lines (sterile line, maintainer line and restoring line).在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句