Sprayer hygiene and concerns of off-target injury from auxin herbicides have increased in recent years. New auxin tolerant crops have broadened the use patterns of these herbicides. Therefore, experiments were conducted across two locations in Mississippi in 2016, 2017, and 2018 to evaluate sprayer cleanout procedures to aid in dicamba removal. Standard sprayer cleanout consisted of a triple rinse of 10% tank volume, with either a tank cleaner or ammonia added in the second rinse. Samples collected in each rinse step for all treatments were applied to actively growing soybean and dicamba concentration quantified with HPLC. Experiments were conducted to determine if various tank cleaners and ammonia produce visual injury when applied to actively growing soybean and cotton alone and in conjunction with glyphosate. No tank cleaner caused visual injury nor affected plant heights or yield. Furthermore, experiments were conducted to evaluate tank cleaner effectiveness to remove dicamba utilizing the standard cleanout procedure, with increased rinse volumes, sequence of water and tank cleaner rinses, and cleanout effectiveness following durations of idle time from application to cleanout. No tank cleaner provided greater dicamba removal, with all cleaners performing the same as cleanouts utilizing water alone. Increasing rinse volumes did not positively affect dicamba removal compared to 10% rinse volumes. Multiple rinse steps utilizing a tank cleaner or altering the standard cleanout procedure utilizing a water-tank cleaner-water rinse sequence did not result in greater dicamba removal from contaminated sprayer systems. Finally, increases in time between contamination with dicamba and cleanout did not negatively influence dicamba removal using the standard cleanout procedure.

No description available.

No description available.

No description available.

Approximately 475 acres of aspen, oak brush, and grass-forb-shrub communities were treated with herbicides. The populations of arthropods, birds, and mammals were investigated on treated and untreated areas and the results were compared. There was no difference between soil arthropod populations on treated and untreated aspen plots but a significant increase in these populations on treated meadow plots. The foliage insect populations were significantly lower on the treated aspen plots but were significantly higher on the treated meadow plots. The aquatic invertebrates were not affected by the treatments. Bird populations ware lower in the treated area during the nesting season (June), higher in the treated area during July and August and nearly the same in each area during September. Small mammal populations decreased significantly on the treated meadow plots. Microtus populations increased while all other small mammals decreased in numbers on treated aspen plots. Use of the treated areas by mule deer was significantly reduced, while use of the same areas by elk was slightly increased.

Bentazon, (3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-l-2,2-dioxide) a new experimental herbicide, was studied under the effects of sterile and non-sterile conditions, 12 hours light: 12 hours dark and totally dark conditions, and agitated and non-agitated conditions in aquatic sediment. The effects of the different levels of BOD/COD values on the decomposition of Bentazon were studied. Photoperiod, sterility, and BOD/COD levels appeared to have no influence in the breakdown of Bentazon. Agitation-time interaction appeared to be the only factor that influenced the more rapid degradation of Bentazon. Bentazon was the major 14C-residue found in the water; it was followed by an unknown. The third major metabolite was 2-amino-N-isopropyl benzamide, followed by anthranilic acid and N-isopropylsulfamoyl anthranilic acid at minor amounts. Only Bentazon was found in the soil. The ratio of radioactivity in the soil vs. the water was 1:1 in the agitated tanks and 1:3 in the non-agitated tanks. After 128 days, the concentration of Bentazon in the water decreased to an average of 50% in the agitated tanks and an average of 80% in the non-agitated tanks.

В работе представлены результаты исследования влияния производных 1,2,4-триазинов на ранние этапы онтогенеза растений ячменя. Объект исследования – производные 1,2,4-триазины. Охарактеризовано влияние исследуемых веществ на всхожесть семян, параметры роста проростков и активность перекисного окисления липидов. Показано, что исследуемые вещества №2, 6, 10 и 11 проявляют гербицидную активность. Работа изложена на 43 страницах, содержит список использованной литературы из 62 источников, 21 рисунок и 1 таблицу. / The paper presents the results of a study of derivatives of 1,2,4-triazines at the early stages of ontogenesis of barley plants. The object of research is derivatives of 1,2,4-triazines. The influence of the studied substances on the germination of seeds, the parameters of the growth of seedlings and the activity of lipid peroxidation is characterized. It is shown that the investigated substances № 2, 6, 10 and 11 exhibit herbicidal activity. The work is presented on 43 pages, contains a list of used literature from 62 sources, 21 figures and 1 table.

CGAr92194 {α-[1,3-dioxolan-2-yl-methoxy)imino]benzeneacetonitrile} is a herbicide safener that is used as a seed dressing agent (1.25 g ai/kg seeds) to protect grain sorghum [<i>Sorghum bicolor</i> (L.) Moench] against metolachlor [2-chloroi-<u>N</u>-(2-ethyl-6-methylphenyl-<u>N</u>-(2-methoxy1-methylethyl)acetamide] injury. The potential adverse phytotoxic effects and the mechanisms of the protective action of this safener were studied in laboratory experiments. Adverse phytotoxicity was assessed by comparing CGA-92194 and the herbicide safeners cyometrinil {(Z)-α[(cyanomethoxy)imino]benzeneacetonitrile} and flurazole [phenylmethyl 2-chloro-4-(trifluromethyl)-5-thiazolecarboxylate] for their effects on CO₂ fixation, protein, DNA, RNA and lipid syntheses of enzymatically isolated leaf cells of soybean [<u>Clycine max</u> (L.) Merr]. At physiological concentrations of less than 10 μM, CGA-92194, cyometrinil and flurazole were stimulatory of all metabolic processes. At 100 μM, the safeners were inhibitory of the five processes with flurazole being the most potent. The mechanisms of the safening action of CGA-92194 were studied by examining the potential interactions of this safener with metolachlor at the levels of uptake and macromolecular syntheses in enzymatically isolated leaf mesophyll protoplasts of grain sorghum. The influence of CGA-92194 on the <i>in vitro</i> reactivity of metolachlor with glutathione (GSH) and it metabolism by sorghum seedlings were also examined. When CGA-92194 and metolachlor were given simultaneously, CGA-92194 enhanced the uptake of ¹⁴C-metolachlor into the sorghum protoplasts in a concentration-dependent pattern. Thus, interference with herbicide uptake is not involved in the protective action of this safener Treatments with metolachlor and CGA-92194 in combination inhibited the incorporation of ¹⁴C-uracil, ³H-thymidine and ¹⁴C-acetate into sorghum protoplast macromolecules less than metolachlor given alone, suggesting the potential involvement of a competitive antagonism in the mechanism of action of CGA-92194. The metabolic activity and growth of sorghum seedlings grown from CGA-92194-pretreated seeds was significantly lower than that of seedlings grown from untreated seeds at 10 or 20 days after planting, The relationship of these effects of CGA-92194 to its safening action is unclear at the present time. CGA-92194 increased the <i>in vitro</i> chemica1 reactivity of metolachlor for GSH in a concentration-dependent pattern, Sorghum seedlings grown from safener-pretreated seeds enhanced ¹⁴C-metolachlor absorption and stimulated its metabolism <u>via</u> conjugation to GSH. This stimulation was reduced by tridiphane [2-(3,5-dichlorophenyl)-2-(2,2,2-trichloroethy1)- oxirane] a potent inhibitor of plant GSH-<u>S</u>-transference enzymes, These results indicate that a safener-induced stimulation of the spontaneous or enzymatic conjugation of metolachlor with GSH is most likely involved in the protective action of CGA-92194. It is suggested that the safening mechanism of action of CGA—92194 involves a sequence of multilevel interactions which together contribute to the overall protection of grain sorghum from metolachlor injury. / Ph. D. / incomplete_metadata

The main objective of this project was to determine the possibility and feasibility of creating wildlife clearings through the use of herbicides as compared to conventional methods of bulldozing and hand clearing. The selected study area adjoining a series of 3 compartments designated as Broad Run Research Area, designed to study various methods of habitat manipulation. Twelve areas were selected for treatment and numbered consecutively. Two were abandoned; No. 1 because of its small size and No. 3 because of the value in its natural condition. A square clearing design was arranged in each of the remaining 10 areas. Four herbicides were selected for testing, each proposed clearing was divided into 4 equal sections in order to apply the 4 herbicides to each clearing; one per quarter-section. The 4 herbicides tested were Monuron, Fenuron, 2,4,5-T, and Ammonium sulfamate. Nonuron and Fenuron, in granular form, were applied around the base of each stem at rates of 5 and 10 grams per stem. Stems 0-4.9 inches d.b.h. received 5 grams and stems 5 inches d.b.h. and larger received 10 grams. Ammonium sulfamate and 2,4,5-T were applied to frills cut at waist height. The ax cute in 2,4,5-T treatment were spaced at 4 inch intervals, and in the ammonium sulfamate treatment were continuous and overlapping. These two chemicals were applied by the use of 2 gallon garden sprayers; ammonium sulfamate at a rate of 7lbs. of crystals dissolved in 2 gallons of water and 2,4,5-T at a rate of 12 lbs. active ingredient per 100 gals. of No. 2 diesel fuel. Frills were filled to overflowing. The granular herbicides were applied in June and July 1958 and the frill treatments were made in August of that year. Two stem counts by species were made on each entire area. The first was made immediately after treatment and the second after one complete growing season. The percent of kill was computed for each herbicide based on the stem counts. Herbaceous sample plots 1/100 acre in size, were established in 4 areas representing 4 topographical features. Two stem counts were made on each of these 4 areas. An incidental field study using 1,2, and 4-grams of Fenuron per stem revealed that most woody species can be controlled with 1 gram of active ingredient per stem. Openings were satisfactorily established with Fenuron and Monuron; a lower rate of application could have been used. Techniques used in frilling would have to be altered to obtain satisfactory results when using 2,4,5-T and ammonium sulfamate; complete frills are necessary for 2,4,5-T treatments and the ax cuts placed closer to the root collar in ammonium sulfamate treatments. Sight observations revealed the areas were being used by deer, rabbit, grouse, turkey, and woodcock. / Master of Science

Six combinations of grazing, tillage, and herbicides were studied during 2 yr in a randomized block design to determine alfalfa (Medicago sativa) survival, corn (Zea mays) plant populations and corn growth in an alfalfa-corn rotation. Alfalfa was overseeded with rye (Secale cereale) in autumn prior to planting corn in spring of each year. Treatments were 1) non-grazed control with standard chemical treatments for no-till establishment of corn, 2) grazing alfalfa, then grazing rye until corn planting followed by dicamba application, 3) alfalfa grazing plus glyphosate prior to corn planting, 4) treatment 3 plus grazing prior to rye jointing, and 5) alfalfa grazing plus autumn application of glyphosate, 6) alfalfa grazing plus autumn disking (no herbicides). Grazing until corn planting decreased (P<0.05) alfalfa stands and rye biomass, but increased (P<0.05) corn plant populations and soil bulk density compared to shorter grazing periods. Grazing prior to rye jointing increased (P <0.05) soil bulk density and corn plant populations, and decreased (P<0.05) rye biomass compared to no spring grazing. Autumn disking decreased (P<0.05) bulk density, but generally provided less (P<0.05) control of alfalfa compared to autumn application of glyphosate. Autumn disking and glyphosate application (Trts. 5 and 6) increased (P<0.05) rye biomass compared to no autumn treatment (Trts. 3 and 4). Applying glyphosate prior to corn planting (Trts. 3 and 4) improved (P<0.05) corn populations and growth compared to autumn glyphosate or disking (Trts. 5 and 6) and was similar to conventional no-till establishment (Trt. 1). Herbicides were necessary to completely kill alfalfa, but grazing reduced TNC in alfalfa roots and alfalfa plant persistence. / Master of Science