Identification of paraquatresistant <i>Solanum nigrum</i> and <i>S americanum</i> biotypes

Abstract

Sweetpotato (Ipomoea batatas (L) Lam) plants are highly susceptible to weed competition during their early field establishment period For a long time the contact herbicide paraquat has been widely used within the sweetpotato production system often as the only herbicide applied to control weeds that emerge within the crop A low rate of paraquat is applied repeatedly over the crop each season eliminating seedling weeds at a very young stage until the crop canopy provides adequate competition However the application of paraquat to selectively destroy seedling weeds has inadvertently selected for paraquatresistant weed biotypes This study confirms growers field observations that populations of paraquatresistant solanaceous weeds are now common identifying them as Solanum nigrum L and S americanum Mill Paraquat cannot be used selectively when these resistant biotypes are present as the concentrations required to control the weed species would be lethal to the crop itself

Effect of Sweet Potato Vine Planting Orientation on the Growth and Yield of Sweet Potato/Maize Intercropping System in Makurdi, Southern Guinea Savanna, Nigeria

“…This may increase competition and therefore affect the water and nutrient uptake of the subterranean nodes in the other vine orientations than in the horizontal vine orientation. [20] also made a similar observation in their study and reported that the subterranean nodes in horizontal vine orientation had more space to draw up nutrients and water which facilitated photosynthesis and production of photoassimilates [11].…”

AtPQT11, a P450 enzyme, detoxifies paraquat via N-demethylation

“…Paraquat resistant weeds have emerged after the wide use of paraquat in agriculture. The underlying mechanisms of paraquat resistance in weeds have been studied mostly at physiological and biochemical levels [3][4][5][6] . From these studies, two major mechanisms of paraquat resistance were suggested, including defects in paraquat translocation restricting the transport of paraquat to chloroplasts 4,7 , and enhanced antioxidation scavenging ROS more efficiently 8,9 .…”

AtPQT11, a P450 enzyme, detoxifies paraquat via N-demethylation

“…Paraquat resistant weeds have emerged after the wide use of paraquat in agriculture. The underlying mechanisms of paraquat resistance in weeds have been studied mostly at physiological and biochemical levels 3–6 . From these studies, two major mechanisms of paraquat resistance were suggested, including defects in paraquat translocation restricting the transport of paraquat to chloroplasts 4,7 , and enhanced antioxidation scavenging ROS more efficiently 8,9 .…”