Effects of Various Nitrogen Regimes on the Ability of Rapeseed (Brassica napus L.) to Suppress Littleseed Canarygrass (Phalaris minor Retz.)

Using crops to control invasive weeds is an important approach for the long-term management of species in agroecosystems. Nitrogen application can improve yield and quality crops, but may shift interactions potentially affecting grass ability. To explore a crop its efficacy weed under different nitrogen conditions, we studied competitive effects high-value rapeseed (Brassica napus L.) on growth photosynthetic characteristics littleseed canarygrass field experiments. The results showed that were significantly affected (p < 0.05) N regimes, by increased first then decreased with increase basal rates, while increasing topdressing rates rapeseed. In fact, was most ideal when both 90 kg·ha−1. We also found impacted ability toward canarygrass, had highest With balance index (CB) initially beyond optimal level. CB continually rates. Our research level period significant effect 0.01) rate (Pn) chlorophyll content (Chl) canarygrass. Under same regime, Pn Chl higher than December, February. study indicated stages differ their sensitivity creating dynamic relationship. Together, our demonstrated fertilizer could help produce yields greater efficacy, suggesting future modeling or experimental studies utilizing should carefully consider timing placement N.