abstract the critical period of weed control (cpwc) is a period in the crop growth cycle during which weeds must be controlled to prevent yield losses. in order to determine the critical period of weed control (cpwc) of corn in hamedan, an experiment was conducted in 2007 at agricultural research station of bu-ali sina university of hamedan. the experiment was carried out as a randomized comple...

This paper demonstrates the framework and methodology how weed population dynamics can be predicted using rule-base fuzzy logic as applied to GIS spatial image. Parthenium weed (parthenium hysterophorus L.) infestation in the Central Queensland region poses a serious threat to the environment and economic viability of the infected areas. Government agencies have taken steps to control and manag...

The largest known infestation of alligator weed Alternanthera philoxeroides (Mart.) Griseb. in Victoria, Australia, was reported in January 2009 in an urban pond. To determine how long the infestation had been present, high quality digital aerial images (orthophotos) were gathered for the site. Since all infestations are subject to ongoing eradication programs in Victoria, historical orthophoto...

In the context of site-specific weed management by vision systems, an efficient image processing for a crop/weed discrimination is required in order to quantify the Weed Infestation Rate (WIR) in an image. This paper presents a modeling of crop field in presence of different Weed Infestation Rates and a set of simulated agronomic images is used to test and validate the effectiveness of a crop/w...

Variability of weed infestation needs to be assessed for site-specific weed management. Since manual weed sampling is too time consuming for prctical applications, a system for automatic weed sampling was developed. The system uses bispectral images, which are processed to derive shape features of the plants. The shape features are used for the discrimination of weed and crop species by using a...

The spatial variation in plant species associated with intercropping is intended to reduce resource competition between species and increase yield potential. A field experiment was carried out on corn (Zea mays L.) and soybean (Glycine max L.) intercropping in a replacement series experiment with weed contamination consist of: weed free, infestation of redroot pigweed, infestation of jimsonweed...

in order to determine the practical method to predict economic production of wheat in competition with feral rye by using regression models, a factorial experiment was carried out based on randomized complete block design with three replications in dargaz. iran. experimental factors were included wheat cultivars (sayson, alvand, chamran and sepahan) and feral rye densities (0, 20, 40, 60 and 80...

This paper describes the modeling of a weed infestation risk inference system that implements a collaborative inference scheme based on rules extracted from two Bayesian network classifiers. The first Bayesian classifier infers a categorical variable value for the weed–crop competitiveness using as input categorical variables for the total density of weeds and corresponding proportions of narro...