Assessment of an invasive weed "Maimaio" Commelina foecunda in the sesame fields of western zone of Tigray, Northern Ethiopia.
Sesame (Sesamum indicum L.) is probably the most ancient oilseed. It has multiple uses; it is used as a source of food and in the pharmaceutical and cosmetics industries. The average yield of sesame in western Tigray is too low (about 400 kg/ha to 500 kg/ha) due to different factors, and weed infestation takes a lion's share. More than 80 weed species were recorded and identified as weed pests for sesame in western Tigray. "Maimaio" Commelina foecunda is the most troublesome weed of sesame. The purpose of this study was to assess the distribution of C. foecunda and quantify its infestations. The survey was conducted in 24 sesame growing areas and 48 sesame farms from the three districts of western Tigray in the 2017 production season. The survey result showed that about 91.7% of the assessed sesame farms in western Tigray were found infested with C. foecunda. The weed frequently appeared in Kafta Humera. And, it occurred abundantly and closely in Kafta Humera, whereas it occurred poorly and irresolutely in Tsegede. Concentrated frequency, abundance, and density of the weed were recorded by large-scale sesame producers, lower growing altitudes, and early growth stage of sesame; whereas, it was limited in the small-scale farms, higher growing altitudes, and late growth stage of sesame.