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实地访问、调查表明，串珠藁本（ＬｉｇｕｓｔｉｃｕｍｍｏｎｉｌｉｆｏｒｍｅＰｅｎｇＺＸｅｔＺｈａｎｇＢＹ，ｓｐ．ｎｏｖ．）广布于甘肃南部与青海东部海拔２２００ｍ以上的高寒阴湿区，随海拔的升高，其发生危害也越重。在各类杂草中串珠藁本占６１．０％～９８．０％．还发现前茬是蚕豆、油菜的小麦田发生较轻，前茬是小麦、青稞的蚕豆、油菜田发生则较重。田间试验表明，串珠蒿本密度与小麦产量呈显著负相关，当每公顷密度由０增至９００万株时，小麦每公顷减产由０增至８５２．０ｋｇ．
Field surveys showed that Ligusticum moniliforme Peng ZXet ZhangBY sp.nov. Was widely distributed in the alpine humid areas above 2200 m above sea level in southern Gansu and eastern Qinghai Province. As the altitude increased, the harms were more serious. Beads in all types of weeds accounted for 61.0% ~ 98.0%. Also found that the former crop is broad bean, rape wheat field occurred less light, the former crop is wheat, barley beans, rape field is heavier. Field experiments showed that the density of Artemisia annua was negatively correlated with the yield of wheat. When the density per hectare increased from 0 to 9 million, the yield per hectare decreased from 0 to 852.0 kg.