Common Allergenic Weeds: Their Pollen Morphology and Management Measures

Weeds and trees usually produce sufficient quantities of lightweight pollen for their pollination. A single plant can produce 1 million to several million pollen grains in a day, exposure to them may lead to pollen allergy or seasonal rhinitis/ rhinosinusitis, asthma and dermatitis etc. Allergenic response is mainly dependent on the correlation between the onset of symptoms and plant pollination time. According to many studies approximately 60-75% of seasonal rhinitis is attributed to weed pollens, 40% to grass weed pollens, and 10% to tree pollens. The pollinating season of the various plants depends on the individual species and their geographical location. In this paper flowering/pollination periods, pollen morphology and management measures of common allergenic weeds are reviewed. Based on their pollination period, weeds can be removed before flowering and can be utilized as biomass in agriculture/industry.