The secretory canals were distributed in the pericycle and secondary phloem of root, in the phloem and pith of stem, and in the phloem and above xylem of the vein in leaf.是什么意思_The secretory canals were distributed in the pericycle and secondary phloem of root, in the phloem and pith of stem, and in the phloem and above xylem of the vein in leaf.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句