来源： Bolfrey-Arku Undated
In Ghana, Imperata cylindrica has become a serious problem in forest, transition and coastal savanna areas, where human population pressure on land has prevented the re-establishment of the forest vegetation. Forest, forest-savanna-transition, and coastal savanna zones, which are intensively cropped to cereals, legumes, vegetables, root and tuber crops are prone to frequent burning, which contributes to the dominance of the weed. The inability of the Ghanaian small-scale farmer to effectively manage I. cylindrica has led to its increased spread and, hence, a major constraint to food production in those area (Bolfrey-Arku et al. Undated).
In Ghana, fifty-one percent of farmers reported of inadequate level of control of Imperata cylindrica with current control practices. Farmers relied mainly on manual methods of weed control supplied mostly by family labor. Glyphosate was applied on fields with > 50% cogon grass cover. Follow-up weed control could be required 3-6 times/season depending on initial land preparation, type of crop and/or level of infestation. Cost of weed control was 20–60% higher on cogon grass-infested field ($71/weeding/ha) than on other fields, and weeding may take 20–25 man-days/ha. The development of a comprehensive management strategy for I. cylindrica and other weeds should be a priority research because the weed threatens the livelihood of over 200 million people in West Africa. (Bolfrey-Arku et al, undated).
农业: Imperata cylindrica is a problematic invasive agricultural weed in Ghana. The cost of weed control was 20 to 60% higher in I. cylindrica-infested fields ($71/weeding/ha) than in other fields. Eighty- six percent of fields that relied on slash-burn method of land preparation had severe I. cylindrica infestation. Infestations > 50% cover, mean density of 33 plants m-2 and shoot height range of 15–300 cm were observed on 60% of the fields. Farmers perceived average yield losses of 30–80% ha–1 due to speargrass interference, implying a national average crop loss ha-1 of $31–$84, $155–$414 and $272–$727 for maize, cassava and yam systems, respectively. Reductions in food quality due to the piercing nature of the rhizomes was also problematic (Bolfrey-Arku et al, undated).
最后修改 ： 7/04/2010 12:19:51 p.m.