| 姓名：German |  | 5.188.211.** | | 時間：2020/7/29 下午 03:51:29 | | ☆☆☆☆☆ | | I'm self-employed ***://xxxvideo.site/ babesglamour We can only wonder now whether it was the close planting of larches that has led to the development of the disease that is now killing larches in Britain. The disease, caused by an organism called Phytophthora ramorum, is more rampant on the wetter, western side of the country, which seems to suggest that cultural conditions have something to do with its prevalence. In Oregon and California P. ramorum is killing oak trees; in Britain oak trees in the wild are hardly affected. The explanation is that the American form is a different mating type. The usual assumption, that a fungal pathogen like phytophthora is transmitted by contact, seems ill-founded. Like many other pathogens affecting trees, the lethal forms of phytophthora seem to develop within intensive plantings. Chalara fraxinea, the organism now killing ash trees, has, as its name suggests, always been associated with ash trees. It became a lethal pathogen within European plantations, possibly within the nursery industry.
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