Experiments were carried out on fields in order to collect data on the effect of early weed competition on maize, including the competition for nutrients and the possible rate of nutrient removal
In a previous study, row spacing ranging from 15 to 45 cm had little effect on rice yield in the absence of weed competition, but under weed competition, wider rows produced significantly lower grain yield (Akobundu and Ahissou, 1985).
Furthermore, studies of the mechanisms of weed competition in maize have considered only competition for resources such as soil moisture, nutrients and light.
durations was significantly higher than weed free crop and resulted in a considerable reduction in crop growth and yield. The maximum reduction in crop growth rate (38%), leaf area index (44%) and grain yield (51%) were recorded in full season weed-crop competition as compared with weed free crop.
Although weed research in maize has broadened from an emphasis on herbicide technology to include studies of weed–maize competition, many studies only consider competition descriptively (e.g. defining the critical period for weed control).
Successful cultivation of maize depends largely on the efficacy of weed control. Weed control during the first six to eight weeks after planting is crucial, because weeds compete vigorously with the crop for nutrients and water during this period.
So, crop weed competition indicates competition between crop and weed in a natural ecosystem in response to resources struggle for their existence and superiority. Crop weed competition occurs in two broad aspects: 1. Direct competition- for nutrient, moisture, light and space 2.
conducting any crop–weed competition study. Additive Design. Also known as partial additive (Rejma´nek et al. 1989), this is the most commonly used experimental design to study the outcome of crop–weed competition. Crop density is held constant while weed density is changed (Figures 1a and 1b). It is relevant to most agricultural situations
The presence of weeds on fields is a concern for farmers, due to competition with the commercial crops, reducing yields. The intercropping of maize with legumes provides weed control; after senescence, the nutrients accumulated by plants are released, recycling nutrients. The study of plant species and their diversity is called phytosociology.
A field experiment was conducted for two consecutive years to study the effect of fertilizer application methods and inter and intra-row weed-crop competition durations on density and biomass of different weeds and growth, grain yield and yield components of maize.
The neighborhood design has been used to study crop–weed competition (Bussler et al. 1995) or weed–weed competition (Pacala and Silander 1990). It may be most appropriate in the context of crop–weed competition to study the effects of crop density and planting pattern on resulting weed competition.
Tilman D (1990) Mechanisms of plant competition for nutrients: the elements of a predictive theory of competition. In: Grace JB and Tilman D, (eds). Perspectives on Plant Competition, pp. 117–141. San Diego, CA: Academic Press. Zimdahl RL (1980) IPPC #31‐A‐80, (ed). Weed‐Crop Competition, a Review.