Weed Tolerance and Suppressive Ability of Potato Cultivars to Natural Weed Infestations

The concerns such as herbicide-resistant weeds and environmental pollution have increased interest in using weed competitive crop cultivars for weed management. Potato plants are highly vulnerable to weed competition, especially during early and late growing season. In this context, a two-year field experiment was performed to assess weed tolerance and suppressive ability of 15 genetically diverse potato cultivars to natural weed. The results showed that weed interference severely reduced potato plant growth and yield. For instance, weed competition decreased potato plant height by 10–37%, plant fresh weight by 21–44%, plant dry weight by 15–40% and yield by 15–48%. Potato cultivars in the study differed in their ability to suppress and tolerate weeds, with weed dry weight ranging from 146.7 g m^− 2 in Lady Olympia to 428.3 g m^− 2 in Arizona and tuber yield from 13.84 t ha^− 1 in Electra to 25.15 t ha^− 1 in Agria under weedy conditions. Key traits of weed-suppressive cultivars included early emergence, rapid canopy development, and greater plant biomass. Cultivars with greater plant height and higher yields were generally more weed tolerant. Among the evaluated cultivars, Lady Olympia demonstrated the highest weed suppression, reducing weed dry weight by 60% or more, making it suitable for organic farming systems. Agria exhibited superior weed tolerance with minimal yield loss, making it suitable for conventional high-yield farming systems.