scholarly journals Selective chemical control of yellow bristle grass (Setaria pumila) in pasture

2009 ◽  
Vol 62 ◽  
pp. 217-221
Author(s):  
T.K. James ◽  
A. Rahman
Keyword(s):  
Chemical Control ◽  
Growth Stage ◽  
Animal Health ◽  
Extended Period ◽  
Field Trials ◽  
Annual Grass ◽  
Severe Damage ◽  
Herbicide Application ◽  
Poor Control ◽  
Selective Chemical

Yellow bristle grass (Setaria pumila) is a summergrowing annual grass currently expanding in distribution throughout pastures in Waikato Readily grazed in its early vegetative growth stage it is avoided by animals when the seed heads appear as barbed bristles lead to animal health problems particularly around the mouth Three field trials were conducted with several herbicides for control of yellow bristle grass Since yellow bristle grass germinates over an extended period from November to February the best control that could be achieved from a single herbicide application was 70 by 22DPA alone or in combination with either TCA or carbetamide applied in December MSMA was more effective on larger plants Ethofumesate treatment resulted in poor control of yellow bristle grass and severe damage to white clover (Trifolium repens) All herbicides evaluated resulted in variable levels of damage to perennial ryegrass (Lolium perenne)

Selective chemical control of doublegee (Emex australis) in legume pasture

1977 ◽  
Vol 17 (84) ◽  
pp. 80 ◽  
Author(s):  
DJ Gilbey
Keyword(s):  
Chemical Control ◽  
Growth Stage ◽  
Leaf Growth ◽  
Growing Season ◽  
Field Trials ◽  
Emex Australis ◽  
Selective Control ◽  
Selective Chemical ◽  
One Year ◽  
Clover Seed

Seven chemicals were evaluated for selective control of doublegee (Emex australis) in legume pasture in 14 field trials conducted at several sites in Western Australia over three years. The effect of removing doublegee on pasture growth was studied in four field trials over the same period. Three hundred and fifty to 700 g a.i. methabenzthiazuron ha-1 gave good selective control of this weed except at Chapman and Wongan Hills in 1974 where the beginning of the growing season was poorly defined. The selectivity of bromoxynil and WL 6361 1 in one year of trials was similar to methabenzthiazuron but that of asulam and metoxuron was too restricted for practical use when doublegees were sprayed at the 2-4 leaf growth stage, 2,4-DB showed selectivity on doublegees with 12 leaves, and no herbicides were satisfactory on doublegees with more than 12 leaves at the time of spraying. Pasture growth and clover seed production was not substantially increased by controlling doublegee.

Chemical control of potato tuber moth, Phthorimaea operculella (Zell.), in Rhodesia

1967 ◽  
Vol 57 (2) ◽  
pp. 271-278 ◽  
Author(s):  
Margaret E. Richardson ◽  
D. J. W. Rose
Keyword(s):  
Chemical Control ◽  
Good Control ◽  
Field Trials ◽  
Phthorimaea Operculella ◽  
Macrosiphum Euphorbiae ◽  
Control Field ◽  
Azinphos Methyl ◽  
History Of ◽  
New Compounds ◽  
Made In

An account is given of the history of chemical control Phthorimaea operculella (Zell.) in potato fields in Rhodesia since the introduction of DDt prior to 1952. The failure of DDT and endrin, in routine spraying, to control field infestations is reproted, and some evidence that this is due to insecticide resistance is given. The results of critical field trials made in 1961, 1964 and 1965 to evaluate a range of insecticides for control of P. operculella and for their effects on populations of Macrosiphum euphorbiae (Thos.) are presented, together with the results of some laboratory tests. Good control of P. operculella in the field was obtained with sprays of azinphos-methyl at the rate of 0.5 lb active ingredient in 20 gal. water per acre, and two new compounds, methidathion and chlorfenvinphos, showed promise for the future.

Fungicide efficacy on tar spot and yield of corn in the Midwestern United States

2022 ◽  
Author(s):  
Darcy E. P. Telenko ◽  
Martin I. Chilvers ◽  
Adam Byrne ◽  
Jill Check ◽  
Camila Rocco Da Silva ◽  
...  
Keyword(s):  
United States ◽  
Growth Stage ◽  
Field Trials ◽  
Corn Belt ◽  
Yield Losses ◽  
Single Application ◽  
Midwestern United States ◽  
Tar Spot ◽  
Significant Yield ◽  
Foliar Fungicide

Tar spot of corn caused by Phyllachora maydis has recently led to significant yield losses in the eastern corn belt of the Midwestern United States. Foliar fungicides containing quinone outside inhibitors(QoI), demethylation inhibitors(DMI), and succinate dehydrogenase inhibitors(SDHI) are commonly used to manage foliar diseases in corn. To mitigate the losses from tar spot thirteen foliar fungicides containing single or multiple modes of action (MOA/FRAC groups) were applied at their recommended rates in a single application at the standard tassel/silk growth stage timing to evaluate their efficacy against tar spot in a total of eight field trials in Illinois, Indiana, Michigan, and Wisconsin during 2019 and 2020. The single MOA fungicides included either a QoI or DMI. The dual MOA fungicides included a DMI with either a QoI or SDHI, and fungicides containing three MOAs included a QoI, DMI, and SDHI. Tar spot severity estimated as the percentage of leaf area covered by P. maydis stroma of the non-treated control at dent growth stage ranged from 1.6 to 23.3% on the ear leaf. Averaged across eight field trials all foliar fungicide treatments reduced tar spot severity, but only prothioconazole+trifloxystrobin, mefentrifluconazole+pyraclostrobin+fluxapyroxad, and mefentrifluconazole+pyraclostrobin significantly increased yield over the non-treated control. When comparing fungicide treatments by the number of MOAs foliar fungicide products that had two or three MOAs decreased tar spot severity over not treating and products with one MOA. The fungicide group that contained all three MOAs significantly increased yield over not treating with a fungicide or using a single MOA.

scholarly journals Hormesis with glyphosate depends on coffee growth stage

2013 ◽  
Vol 85 (2) ◽  
pp. 813-822 ◽  
Author(s):  
LEONARDO B. DE CARVALHO ◽  
PEDRO L.C.A. ALVES ◽  
STEPHEN O. DUKE
Keyword(s):  
Plant Growth ◽  
Weed Management ◽  
Growth Stage ◽  
Growth Stages ◽  
Coffee Plant ◽  
Herbicide Application ◽  
Coffee Plantations ◽  
Plant Growth Stages ◽  
Coffee Plants ◽  
Almost All

Weed management systems in almost all Brazilian coffee plantations allow herbicide spray to drift on crop plants. In order to evaluate if there is any effect of the most commonly used herbicide in coffee production, glyphosate, on coffee plants, a range of glyphosate doses were applied directly on coffee plants at two distinct plant growth stages. Although growth of both young and old plants was reduced at higher glyphosate doses, low doses caused no effects on growth characteristics of young plants and stimulated growth of older plants. Therefore, hormesis with glyphosate is dependent on coffee plant growth stage at the time of herbicide application.

Effect of Spray Components on Glyphosate Toxicity to Annual Grasses

Weed Science ◽  
1983 ◽  
Vol 31 (1) ◽  
pp. 124-130 ◽  
Author(s):  
Douglas D. Buhler ◽  
Orvin C. Burnside
Keyword(s):  
Soil Moisture ◽  
Water Stress ◽  
Plant Growth ◽  
Surfactant Concentration ◽  
Growth Stage ◽  
Annual Grass ◽  
Spray Solution ◽  
Annual Grasses ◽  
Small Grains ◽  
Carrier Volume

Field and greenhouse research was conducted during 1980 and 1981 to evaluate the effects of carrier volume, surfactant concentration, and treatment date on glyphosate [N- (phosphonomethyl)glycine] toxicity to annual-grass weeds and volunteer small grains. Glyphosate phytotoxicity increased as carrier volume was decreased from 190 to 24 L/ha. The presence of a surfactant in the spray solution did not influence grass control when glyphosate was applied in a carrier volume of 24 L/ha. When glyphosate was applied in 48 or 95 L/ha, the presence of surfactant resulted in better grass control than glyphosate without surfactant. When applied in 190 L/ha, glyphosate with 0.5% (v/v) surfactant gave better grass control than glyphosate alone or commercially formulated glyphosate. When glyphosate was applied to plants under water stress, little control was achieved regardless of plant growth stage. Glyphosate application to grass after head initiation also resulted in reduced control. Maximum weed control with glyphosate was attained when applications were made to seedlings growing actively because of adequate soil moisture and favorable temperatures.

scholarly journals Examination of Acephate Absorption, Transport, Metabolism, and Accumulation in Maize After Root Irrigation for Spodoptera Frugiperda Control

2021 ◽  
Author(s):  
jiyingzi Wu ◽  
xianjia Li ◽  
ruiquan Hou ◽  
kunyu Zhao ◽  
yongqin Wang ◽  
...  
Keyword(s):  
Pest Control ◽  
Spodoptera Frugiperda ◽  
Control Method ◽  
Control Measure ◽  
Fall Armyworm ◽  
Extended Period ◽  
Field Trials ◽  
Pesticide Use ◽  
Control Efficacy ◽  
Maize Plants

Abstract BACKGROUND: Since the invasion of the fall armyworm moth (Spodoptera frugiperda) in China in January 2019, damage to maize crops has gradually intensified, and chemical control has become the main control measure. This study aimed to examine methods of effective pest control while monitoring the environmental impact of pesticide use. The effectiveness of S. frugiperda pest control by foliar spraying and root irrigation of maize plants with acephate was determined, and the absorption, distribution, and dissipation of acephate and methamidophos by maize were studied.RESULTS: Field trials showed that acephate treatment at 6000 g.a.i ha-1 was the most effective for controlling S. frugiperda. Acephate and methamidophos were absorbed from the roots, transported upward, and concentrated in the leaves, particularly new leaves. The terminal residues of acephate and methamidophos in maize grains were below detectable levels at 60 days after treatment.CONCLUSIONS: The results demonstrate that acephate treatment via root irrigation can more effectively control the infestation of S. frugiperda in maize than acephate treatment via foliar spraying. The translocation and distribution of acephate and methamidophos by root irrigation were more uniform, and the holding efficiency was higher than those in foliar spraying, suggesting an extended period of control efficacy. This pest control method could be utilized to reduce pesticide residues while safely and efficiently controlling S. frugiperda infestation.

Chemical control of bacterial canker (Pseudomonas syringae pv. syringae) of apricot and cherry in Victoria

1991 ◽  
Vol 31 (5) ◽  
pp. 705 ◽  
Author(s):  
DLS Wimalajeewa ◽  
R Cahill ◽  
G Hepworth ◽  
HG Schneider ◽  
JW Washbourne
Keyword(s):  
Pseudomonas Syringae ◽  
Chemical Control ◽  
Bordeaux Mixture ◽  
Weather Conditions ◽  
Hydrated Lime ◽  
Field Trials ◽  
Bacterial Canker ◽  
Copper Hydroxide ◽  
Low Concentrations ◽  
Excellent Control

Field trials were conducted during 1982-85, to develop a comprehensive spray program for the control of bacterial canker (Pseudomonas syringae pv, syringae) of apricot and cherry. Five spray schedules were evaluated as measures to reduce disease levels. Copper hydroxide at 2.5 g/L in water was applied to apricot, and bordeaux mixture at 6 g copper sulfate + 8 g hydrated lime/L in water was applied to cherry, during autumn, winter and pre-bloom spring. The effectiveness of copper sprays in reducing epiphytic populations of the pathogen during post-bloom spring was also tested. Copper hydroxide was applied to apricot, and a foliar copper nutrient and copper hydroxide were applied to cherry at low concentrations. Most spray schedules tested significantly (P<0.05) reduced canker incidence relative to controls. Excellent control of epiphytic populations of the pathogen on apricot and cherry was achieved with copper sprays applied at post-bloom in spring. A spray schedule consisting of 2 autumn, 1 winter and 2 pre-bloom spring sprays with copper hydroxide on apricot or bordeaux mixture on cherry was successful in reducing canker (>67% reduction) and is recommended for control of the disease. Two applications of copper hydroxide at 1.0 g/L in water in post-bloom spring considerably reduced (>9 1 %) epiphytic populations (P. syringae pv. syringae) on apricot and cherry leaves. Later sprays are recommended for use in combination with the autumn-winter-spring (pre-bloom) spray schedule, especially under excessively wet and cool weather conditions in spring.

scholarly journals Evaluation of gooseberry cultivars resistance to the American gooseberry powdery mildew Sphaerotheca mors uvae Schwein and its chemical control

2017 ◽  
Vol 38 (SI 2 - 6th Conf EFPP 2002) ◽  
pp. 583-587
Author(s):  
M. Vaverka ◽  
S. Vaverka
Keyword(s):  
Biological Activity ◽  
Czech Republic ◽  
Powdery Mildew ◽  
Chemical Control ◽  
Biological Effect ◽  
Field Trials ◽  
The Czech Republic ◽  
Biological Efficacy ◽  
Extensive Field ◽  
Susceptibility Evaluation

In the course of 1993–2001 extensive field trials were carried out to evaluate the resistance (susceptibility) level of 34 gooseberry cultivars to the American gooseberry powdery mildew Sphaerotheca mors uvae Schwein. Cultivars originated from the Czech Republic and from other European countries. Each tested cultivar had 7 trees (5–10 years old). Beside the resistance (susceptibility) evaluation, biological efficacy of 9 fungicides using EPPO methods has been checked at the same number of cultivars and at the same number of gooseberry trees. Highly significant differences of resistance or susceptibility were observed among gooseberry varieties. Analogical results (differences in biological activity of fungicides) have been attained in the course of chemical treatment. 18 cultivars has been classified as low resistant, 12 cultivars as moderate resistant and 4 cultivars as high resistant. None of the tested fungicides proved perfect biological efficacy (100% healthy berries). 4 of them proved high biological effect (more than 90% healthy berries), 3 proved low biological activity (less than 75% healthy berries) and 2 proved moderate biological activity (75–90% healthy berries).

Influence of Simulated Rainfall and Soil Moisture on Herbicidal Activity of Cinmethylin

Weed Science ◽  
1990 ◽  
Vol 38 (3) ◽  
pp. 267-272 ◽  
Author(s):  
Steven G. Russell ◽  
Thomas J. Monaco ◽  
Jerome B. Weber
Keyword(s):  
Weed Control ◽  
Sandy Loam ◽  
Field Trials ◽  
Herbicidal Activity ◽  
Herbicide Application ◽  
Weed Species ◽  
Green Foxtail ◽  
Loam Soil ◽  
Dry Soil ◽  
Prickly Sida

Field trials were conducted in 1986 and 1987 to determine the effects of moisture on herbicidal activity of cinmethylin applied preemergence at 0.0, 0.3, 0.6, and 0.9 kg ai ha to both dry and moist sandy loam soil. Herbicide application was followed by varying amounts of irrigation. Weed species included velvetleaf, prickly sida, green foxtail, and barnyardgrass. When cinmethylin was applied to a moist soil or when 2.5 cm of irrigation was applied 5 days after cinmethylin application to a dry soil, overall weed control was reduced. Optimum weed control resulted from cinmethylin application to dry soil followed either by a 2.5-cm irrigation within 8 h or a 7.6-cm irrigation within 36 h.

Weeds and yields of spring cereals as influenced by stubble-cultivation and reduced doses of herbicides in five long-term trials

2000 ◽  
Vol 134 (3) ◽  
pp. 237-244 ◽  
Author(s):  
U. BOSTRÖM ◽  
M. HANSSON ◽  
H. FOGELFORS
Keyword(s):  
Weed Management ◽  
Plant Density ◽  
Crop Yields ◽  
Field Trials ◽  
Herbicide Application ◽  
Weed Species ◽  
Full Dose ◽  
Spring Cereals ◽  
One Year

The influence of herbicides at reduced rates and repeated stubble-cultivation on weeds and crop yields was estimated in five field trials with spring-sown cereals situated in the south of Sweden during the autumn of 1989 until the spring of 1997. Stubble-cultivation was accomplished during 1989–1996, while herbicides were applied at 0, 1/8, 1/4 or 1/2 of full dose during 1990–1996.In the spring of 1997, i.e. after 7 years without herbicide application, seedling densities 3 weeks after weed emergence were 68–340/m2 at three sites and 535–610/m2 at two sites when averaged over tillage treatments.Averaged over herbicide doses, stubble-cultivation reduced the plant density of annual broad- leaved weeds by 6–32% at three sites and increased the density by 25% at one site. At the remaining site, the density was not significantly influenced. Stubble-cultivation reduced the populations of two perennial and seven annual weed species, while one species was stimulated and nine species showed null, or inconsistent, responses. In the spring of 1997, i.e. one year after the last herbicide application, the densities of weed seedlings in 1/8, 1/4 and 1/2-doses were 34, 46 and 56% lower, respectively, than in the untreated controls.Stubble-cultivation increased crop yields at four sites by 200 kg/ha as a mean over herbicide doses. At these four sites, averaged over 1993–1995, herbicides increased yields in plots that were not stubble-cultivated by 7, 8 and 10% in the 1/8, 1/4 and 1/2 of a full dose, respectively, relative to the untreated control. In 1996, herbicides increased yields at only two sites.It is concluded that a fruitful way for weed management with a low input of agrochemicals is to combine the use of herbicides at reduced rates with repeated stubble-cultivation.

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