HERB and MSU-HERB Field Validation for Soybean (Glycine max) Weed Control in Mississippi

Abstract

In 1994, herbicide efficacy and competitive index databases were adjusted in the soybean herbicide recommendation program HERB to best reflect data for Mississippi. Field experiments were conducted to compare efficacy and economics of postemergence herbicides recommended by HERB and MSU-HERB. The study was conducted utilizing four locations over 2 yr, which provided different soil types, weed spectra, and environmental conditions with which to evaluate weed control from herbicides recommended by these programs. HERB and MSU-HERB agreed on an herbicide recommendation in 62% of the modeling runs. Herbicides recommended by both software versions were generally effective for controlling the predominant weed species at each location. In instances where there was a significant difference in herbicide efficacy between herbicides recommended by HERB and MSU-HERB, improved weed control resulted from herbicides recommended by MSU-HERB. In 1994, excellent moisture conditions enabled soybean to gain a significant competitive advantage over weeds and, as a result, yield loss predictions after treatment were overestimated in most instances. Conversely, 1995 environmental conditions better represented average Mississippi growing conditions, and yield loss predictions after treatment were more accurate. Yield loss prediction accuracy of HERB versions was related to the length of interference between soybean and weeds. Thus, prediction accuracy of HERB and MSU-HERB was similar. Soybean yield increase and net economic gain following MSU-HERB recommendations was as high or higher than following HERB recommendations.

Evaluation and Adaptation of the HADSS®Computer Program in Texas Southern High Plains Cotton

“…The diversity of field trials covers a large geographical region, which offers a wide array of cotton varieties, environmental growing conditions, and a large spectrum of weeds (Wilkerson et al 1991). Rankins et al (1998) reported that changes to the competitive indices and efficacy ratings of HERB for different environments improved its use, and in a comparison between the original version of HERB and one adapted to Mississippi (MSU-HERB), improved weed control was seen from herbicides recommended by MSU-HERB, which resulted in higher soybean yields and net returns. The HADSS program uses a database to make recommendations.…”

Weed control in summer‐sown soybeans with flumioxazin plus acetochlor and flumiclorac‐pentyl plus clethodim

“…It is hard and expensive for farmers to hoe them by hand. Until now, some herbicides, such as acetochlor, fomesafen, haloxyfop and trifluralin have been widely used to control weeds in the soybean crops (Rankins et al . 1998; Zhao et al .…”

Benefits and Limitations of Decision Support Systems (DSS) with a Special Emphasis on Weeds

“…Developing an accurate and effective DSS for weed management has long been recognized as a primary goal for agronomists, land and crop managers and weed scientists [27]. A DSS can be in a simple form, such as a software that indicates the appropriate herbicides recommended for weed specific threshold concepts [28]. More complicated DSSs evaluate herbicide efficacy, the environmental aspect of herbicide treatments and the competitiveness between crops and various weed species, while they may also provide special knowledge on ecosystem diversity and the effects of soil and climatic conditions on the efficacy of herbicide applications [29].…”