梨树与柏树不能种在一起.梨园的果农都知道,在梨园周围不但不能种柏树,而且原先长着的柏树也要砍掉。因为梨树有一种病害叫赤星病,又叫梨锈病。该病是由一种霉菌侵入梨树叶片产生出大量锈孢子,而这些锈孢子不能再侵入梨树,它必须在柏树上越冬。在柏树上的锈孢子开始萌发,以菌丝侵入柏树的组织,度过严冬季节.翌春,气温升高,在柏树枝叶上的冬孢子遇水膨胀,里棕褐色胶状体,干后表面有黄色粉末(担孢子)飞散,随风飘落到梨树上后 Pear and cypress can not be planted together. Pear garden farmers know that not only can not planted in the pear around cypress trees, and the original cypress trees also cut off. Because the pear tree has a disease called brown spot disease, also known as pear rust. The disease is caused by a mold invasion of pear leaves produce a large number of rust spores, and these rust spores can no longer invade the pear tree, it must winch on the cypress. The rust spores on the cypress began to germinate and the mycelium invaded the tissue of the cypress tree and spent the harsh winter season. In the following spring, the temperature rose and the teliospores on the cypress branches expanded in water and the brown colloid and dried surface A yellow powder (basidiospores) fly, the wind fell on the pear after