“缅桂花开十里香”,这是云南一首歌曲的名句。因为“缅桂花”就是云南人给白兰花所起的名字,其它省区是不把它叫做缅桂花的。它是否能香飘十里,我们无需查究。但世界上被认为最香的花就真的叫做“十里香”,它是一种白色的野蔷薇花。在我国,许多种白色的花都是著名的香花,如白兰、含笑、荷花玉兰、荷花、桂花、梅花等。以白兰为例,与它亲缘最接近而花朵呈黄色的黄兰,就很少香味。因此,认为白花最香,在某种意义上说也并不错。然而,花的颜色和香味本身并无必然的联系,它们是由两种不同性质的机理所起作用的结果。花的颜色,是由于花内含有不同的化合物。含类胡罗卜素的花儿着红色,含黄酮类化合物的花儿呈黄色,含叶绿素的呈绿色。花中如果含有花青素时,则还要根据细胞液的酸碱 “Burma osmanthus incense ten miles,” this is a famous song in Yunnan. Because “Burma osmanthus” is the name of Yunnan Province to the white orchid, other provinces is not called it Burmese osmanthus. Whether it can smell fragrant miles, we do not need to investigate. But the world is considered the most fragrant flower is really called “Shili Xiang”, it is a kind of white briar flower. In our country, many kinds of white flowers are famous fragrant flowers, such as brandy, smile, lotus magnolia, lotus, osmanthus, plum and so on. To Prynne, for example, with its close relatives and yellow flowers Huang Lan, very few fragrance. Therefore, the best white flower, in a sense, is not bad. However, the color of flowers does not necessarily correlate with the fragrance itself, and they are the result of two different mechanisms of nature. The color of the flower is due to the different compounds contained in the flower. Flowers containing carotenoids are red, yellow with flavonoids, and green with chlorophyll. If the flower contains anthocyanins, but also according to the cell solution of acid and alkali