Interference and level of economic damage of turnip in canola

Abstract

The weeds if not properly controlled have great ability to settle in agricultural systems, affecting crop production. The objective of this work was to determine the interference and level of economic damage in different density of crop. The treatments were composed of canola hybrids (Hyola 50, Hyola 76, Hyola 433, Hyola 571 CL, Hyola 575 CL and Diamond) and twelve infestation turnip density in crop. The variables evaluated to estimate the competitiveness of the hybrids were plant density, leaf area, soil cover and dry mass of the turnip. Grain yield, canola price, herbicide efficiency, and control cost were used to determine the weed's level of economic damage on the crop. The canola hybrids Hyola 575 CL, Hyola 50, Hyola 76 and Hyola 571 CL are more competitive with turnip. The values of economic damage levels range from 2.86 to 5.95, 2.43 to 5.05, 2.22 to 5.43 and 2.99 to 6.22 turnip plants m-2 for hybrids Hyola 50, Hyola 76, Hyola 571 CL and Hyola 575 CL, respectively, as a function of simulated variables. The increased grain yield, canola price, herbicide efficiency and lower control costs reduce the level of economic damage, justifying the adoption of control.

Interferência e nível de dano econômico de papuã em feijoeiro em função da densidade de plantas

“…The application of herbicides based on the concept of the level of economic damage (EDL) provides for the adoption of the control method only when the damage caused by the weeds is greater than the cost of the control method (KALSING & VIDAL 2013, GALON et al 2016, BRANDLER et al 2021. When using EDL to make crop weed control decisions, the crop's estimated grain yield losses are compared to the costs of the available control options, allowing an analysis of the gain obtained with the control treatment used (KALSING & VIDAL 2013, GALON et al 2016.…”

“…To estimate EDL regression equations or damage functions are usually adopted, they relate crop yield losses to possible weed control measures at the time of post-emergence control (KALSING & VIDAL 2013, GALON et al 2016, BRANDLER et al 2021).…”

“…Among the various factors that affect competition between weeds and crops are those associated with the soil, climate, and management practices. Management practices such as cultivars with higher competitive ability, soil fertility correction, higher sowing density, among others, can reduce the degree of weed competition, increasing the EDL and minimizing the need to adopt control measures (KALSING & VIDAL 2013, PARREIRA et al 2014, GALON et al 2016, BRANDLER et al 2021.…”

“…When this information is available, it can play a significant role in changing the management method that relies mainly upon herbicides to a system based on ecophysiological knowledge (KALSING & VIDAL 2013, PARREIRA et al 2014, GALON et al 2016, BRANDLER et al 2021) and thus has a more sustainable model of weed control.…”

“…Among the many tools available to study plant competition in a community is the non-linear rectangular hyperbola equation. This model relates crop yield loss using the variables weed density, aboveground dry mass, ground cover, and leaf area (KALSING & VIDAL 2013, GALON et al 2016, BRANDLER et al 2021). In addition, the hyperbola model contains parameters (i and a) that have biological and agronomic significance, used as indices of competitiveness (COUSENS 1985).…”