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Full-Text Articles in Plant Sciences
Water Quality, Carrier Volume And Droplet Size Effects On Herbicide Efficacy And Drift Potential, Barbara Houston
Water Quality, Carrier Volume And Droplet Size Effects On Herbicide Efficacy And Drift Potential, Barbara Houston
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Herbicide performance is directly related to the amount of active ingredient that has been deposited on the plant. Hence, spray solution characteristics and application parameters are crucial in determining the efficacy of an herbicide application. To maximize the effectiveness of chemical control, methods to deliver full chemical dose must be utilized: allowing the active ingredient to be readily absorbed once added to the carrier and mitigating off-target movement and low herbicide doses. Water is the most frequently used carrier in herbicide applications. Chemical parameters, such as water hardness and pH, can have a critical role in herbicide performance. It is …
The Influence Of Adjuvants On Physical Properties, Droplet-Size, And Efficacy Of Glufosinate And Dicamba Plus Glyphosate Solutions, Estefania Gomiero Polli
The Influence Of Adjuvants On Physical Properties, Droplet-Size, And Efficacy Of Glufosinate And Dicamba Plus Glyphosate Solutions, Estefania Gomiero Polli
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Adjuvants are used in agriculture to improve herbicide activity or application performance. The addition of adjuvants to herbicide solution can enhance its penetration, wettability, and evaporation rates by altering density, viscosity, contact angle between the droplet and plant surface, and droplet surface tension. Furthermore, those alterations in the physical properties of the herbicide solution can result in changes in the droplet-size distribution that directly impact herbicide efficacy. The adoption of glufosinate-based herbicide programs has increased with the widespread occurrence of glyphosate-resistance (GR) weeds in recent years. Also, tank mixture of dicamba and glyphosate has been largely adopted for broad-spectrum weed …
The Effect Of Spray Parameters On The Application Of Enlist Duo, Matthew R. Nelson
The Effect Of Spray Parameters On The Application Of Enlist Duo, Matthew R. Nelson
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
The emergence of new weed control challenges, along with shifts in weed management strategies and cultural practices, has resulted in an increased reliance on chemical weed control in United States (US) cropping systems. As a result, numerous weed species have evolved resistance to herbicides such as glyphosate, thus prompting the development of new weed control systems designed to aid growers in managing resistant weeds. While these new weed control options may give growers additional management options, the high sensitivity of broadleaf crops, fruits, and vegetables to products containing 2,4-D or dicamba increases the potential for herbicide drift resulting from application …
Emergence, Competition, And Management Of Glyphosate-Resistant Common Ragweed (Ambrosia Artemisiifolia L.) In Nebraska Soybean, Ethann R. Barnes
Emergence, Competition, And Management Of Glyphosate-Resistant Common Ragweed (Ambrosia Artemisiifolia L.) In Nebraska Soybean, Ethann R. Barnes
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Common ragweed (Ambrosia artemisiifolia L.) is a competitive annual broadleaf weed in soybean (Glycine max) production fields throughout North America. The recent confirmation of glyphosate-resistant common ragweed in Nebraska justified the need to assess the emergence pattern and competitive ability of common ragweed in soybean and to evaluate alternative herbicide programs for effective management. The objectives of this research were to: 1) evaluate the effect of tillage and develop a predictive model for the emergence pattern of common ragweed in Nebraska; 2) model the competitive interaction between soybean and common ragweed as influenced by density and irrigation …
Control Of Herbicide-Resistant Volunteer Corn In Herbicide-Resistant Soybean, Parminder Chahal
Control Of Herbicide-Resistant Volunteer Corn In Herbicide-Resistant Soybean, Parminder Chahal
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Volunteer corn is a problem weed in soybean fields because it reduces yield and seed quality, and potentially harbors insects, pests, and diseases. Several pre-packaged herbicides have been registered in soybean in recent years, but response of volunteer corn to these herbicides has not yet been documented. Therefore, the first objective of this study was to evaluate the response of glufosinate-, glyphosate-, and imidazolinone-resistant volunteer corn to 20 pre-emergence (PRE) and 17 post-emergence (POST) soybean herbicides. The results indicated that PRE soybean herbicides partially controlled (< 80%) volunteer corn except clomazone, while acetyl CoA carboxylase (ACCase) inhibiting herbicides provided ≥ 85% control. Germination and emergence are critical stages in weed seed establishment and persistence. Scientific literature is not available about the factors affecting germination and emergence of volunteer corn. The second objective was to determine the effects of different environmental and agronomic factors on the germination and emergence of glyphosate-resistant hybrid and volunteer corn. The results indicated that response of hybrid and volunteer corn to majority of the variables tested was similar, suggesting that volunteer corn can germinate and emerge in a wide range of climatic conditions. Majority of growers control volunteer corn when it is visible above the soybean canopy, but this can results in early season competition with soybean. The third objective was to evaluate the impact of different densities of glyphosate-resistant volunteer corn at different control timings, and late season volunteer corn emergence on soybean yields. Late season volunteer corn emergence had no significant effect on soybean yield. Yield did not decrease with all volunteer corn densities, except with the highest density (10,000 plants and 500 clumps ha-1) at all control timings. Soybean growers are looking for alternative herbicides, such …