Fungicide seed dressings: their effects on emergence of soybean and nodulation of pea and soybean

1980 ◽  
Vol 20 (105) ◽  
pp. 497 ◽  
Author(s):  
GE Stovold ◽  
J Evans
Keyword(s):  
Field Experiments ◽  
Soybean Seed ◽  
Field Trials ◽  
Inhibitory Effect ◽  
Alternative Methods ◽  
Seedling Disease ◽  
Rhizobium Inoculation ◽  
Treated Seed ◽  
Inoculant Carrier ◽  
Seedling Diseases

A range of fungicides was tested for their efficacy as seed treatments for the control of seedling diseases of soybeans. Thiram, captan and captafol at rates of 2000 ppm a.i. w/w or 3000 ppm a.i. w/w provided the most consistent protection in field trials conducted for 3 years at three separate sites. Of these three fungicides, thiram had the least effect on nodulation by Rhizobium applied to the seed, but an inhibiting effect did occur in some years. Several other fungicides had little effect on nodulation but were inconsistent in controlling seedling diseases. In a glasshouse pot trial, the fungicides did not reduce nodulation even though some were consistently toxic in the field experiments. In field trials with peas and soybeans, the inhibitory effect of a toxic fungicide (captan) on nodulation by seed-borne Rhizobium was avoided by using alternative methods of inoculation which separated Rhizobium from the treated seed. A water suspension of peat-based rhizobial inoculant, or sand particles coated with peat inoculant introduced to the furrow together with the seed, were effective methods of inoculation. A large-particle inoculant carrier (heat-killed soybean seed) was unsuitable. For control of soybean seedling disease we recommend the use of thiram fungicide at a rate of 2000 ppm a.i. w/w, and where practicable the use of alternative methods of Rhizobium inoculation to separate the inoculum from the treated seed.

Preemergence Herbicide and Glyphosate Effects on Seedling Diseases in Glyphosate-Resistant Cotton

2005 ◽  
Vol 19 (2) ◽  
pp. 312-318 ◽  
Author(s):  
Joseph H. Pankey ◽  
James L. Griffin ◽  
Patrick D. Colyer ◽  
Raymond W. Schneider ◽  
Donnie K. Miller
Keyword(s):  
Field Study ◽  
Disease Severity ◽  
Field Experiments ◽  
Leaf Growth ◽  
Inhibitory Effect ◽  
Growth Stages ◽  
Seedling Disease ◽  
Greenhouse Study ◽  
Herbicide Treatments ◽  
Seedling Diseases

Field experiments were conducted to evaluate the influence of preemergence (PRE) herbicides metolachlor at 1,700 g ai/ha, pyrithiobac at 70 g ai/ha, or pendimethalin at 840 g ai/ha applied alone or with fluometuron at 1,300 g ai/ha and glyphosate postemergence (POST) at 840 g ai/ha on seedling diseases in glyphosate-resistant cotton. Hypocotyl disease severity both years averaged across PRE herbicide treatments was greater after glyphosate application to four-leaf cotton than cotyledon cotton. The PRE herbicide treatments, particularly those including fluometuron, increased root and hypocotyl disease ratings compared with a nontreated control, and a sequential application of glyphosate did not further increase disease severity. Greenhouse experiments using soil infested withRhizoctonia solaniconfirmed findings from the field study showing that PRE herbicides can predispose cotton to greater seedling disease injury with no increased seedling disease severity associated with application of glyphosate. In the field study, glyphosate applied at cotyledon or four-leaf growth stages decreased disease severity on cotton hypocotyls both years. This inhibitory effect of glyphosate was less evident in the greenhouse study and may have been related to species of fungi present, infestation level, and differences in environmental conditions when compared with the field.

scholarly journals Regression Analyses for Evaluating the Influence of Bacillus cereus on Alfalfa Yield Under Variable Disease Intensity

2000 ◽  
Vol 90 (6) ◽  
pp. 657-665 ◽  
Author(s):  
Elizabeth R. Kazmar ◽  
Robert M. Goodman ◽  
Craig R. Grau ◽  
David W. Johnson ◽  
Erik V. Nordheim ◽  
...  
Keyword(s):  
Bacillus Cereus ◽  
Untreated Control ◽  
Field Experiments ◽  
Seedling Emergence ◽  
Field Trials ◽  
Forage Yield ◽  
Regression Methods ◽  
Control Response ◽  
Treated Seed ◽  
Yield Gain

We developed and tested regression methods to exploit the variability in disease inherent in field experiments, and applied the methods to evaluate strains of Bacillus cereus for biocontrol efficacy. Four B. cereus strains were tested for their effect on alfalfa (Medicago sativa) performance in 16 field trials planted during 1993 to 1996 at multiple sites in Wisconsin. To evaluate performance of the strains, we used the ratio of (metalaxyl response)/(untreated control response) as a measure of disease intensity within the experiments. The ratio of (Bacillus response)/(untreated control response) was then regressed as a function of disease intensity. The slope of the resulting line provides a statistical test to compare performance of the Bacillus strain with that of the untreated seed (Ho: slope = 0) and metalaxyl controls (Ho: slope = 1). Under conditions in which disease occurred, forage yield of plots planted with seed treated with B. cereus strain AS4–12 exceeded yield from the untreated control plots (P = 0.002) and was similar to yield of plots planted with metalaxyl-treated seed (P = 0.14). Yield gain associated with AS4–12 and metalaxyl seed treatment averaged 6.1 ± 2.8% (±standard error) and 3.0 ± 2.8%, respectively. In contrast to the regression approach, means analysis by analysis of variance did not detect differences among treatments. Three other B. cereus strains either did not increase alfalfa yield or increased yield less than did AS4–12. Metalaxyl and three of the Bacillus strains increased seedling emergence, but the improved stands were not predictive of increased forage yield. In six additional studies conducted for one season in 1997, AS4–12 enhanced yield of two cultivars at diverse locations in Wisconsin, but there was an apparent cultivar-location interaction. A strong correlation between response to AS4–12 and metalaxyl treatment suggests that these treatments controlled similar pathogens, most likely the oomycete pathogens Phytophthora medicaginis and Pythium spp.

scholarly journals Development of Strategies to Evaluate Brassica oleracea L. Vegetable Crops for Wirestem Caused by Rhizoctonia solani

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 621c-621
Author(s):  
Mark W. Farnham ◽  
Anthony P. Keinath
Keyword(s):  
Rhizoctonia Solani ◽  
Field Experiments ◽  
Effective Means ◽  
Field Studies ◽  
Field Trials ◽  
Alternative Methods ◽  
Environment Interaction ◽  
Vegetable Crops ◽  
Respective Field ◽  
Controlled Environments

Wirestem, caused by Rhizoctonia solani, is a destructive disease of B. oleracea cole crops and is distributed worldwide. Effective means of wirestem control include soil fumigation and soil treatment with pentachloronitrobenzene, which are increasingly expensive and environmentally undesirable. As a consequence, alternative methods of wirestem control are needed. Thus, we conducted controlled-environment and field experiments to develop methodology to study host-plant resistance and possibly biocontrol agents as potential wirestem control alternatives. Seedlings of 12 cultivars (three each of cauliflower, broccoli, cabbage, and collard) at the four- to five-leaf stage were transplanted to trays in a growth room or into field plots and covered with soil infested with R. solani AG-4 sclerotia. Disease progression (percent of plants healthy, diseased, and dead) was observed every 3 days for 2 weeks in the controlled environments and for 3 weeks in field trials. At the end of two studies, plants were dug with roots intact and rated for disease using a 1 to 10 scale. In all trials, percent healthy plants stabilized at about 2 weeks after inoculation. Incidence of wirestem disease varied among experiments ranging from 70% to 100% diseased, dead plants in controlled environments, and from 51% to 88% and 33% 65% in the two respective field studies. Disease rating was always negatively and significantly correlated with percent healthy plants. Although a genotype × environment interaction was observed, some cultivars (i.e., `Snowcone' and `Snowcrown' cauliflowers) were always severely diseased, while others (i.e., `Viking' broccoli and `Blue Max' collard) were consistently among the least diseased.

scholarly journals COR/LEA Proteins as Indicators of Frost Tolerance in Triticeae: A Comparison of Controlled versus Field Conditions

Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 789
Author(s):  
Klára Kosová ◽  
Miroslav Klíma ◽  
Ilja Tom Prášil ◽  
Pavel Vítámvás
Keyword(s):  
Cold Acclimation ◽  
Field Experiments ◽  
Quantitative Relationship ◽  
Field Trials ◽  
Frost Tolerance ◽  
Late Embryogenesis Abundant ◽  
Field Conditions ◽  
Lea Proteins ◽  
Winter Cereals ◽  
Vernalisation Requirement

Low temperatures in the autumn induce enhanced expression/relative accumulation of several cold-inducible transcripts/proteins with protective functions from Late-embryogenesis-abundant (LEA) superfamily including dehydrins. Several studies dealing with plants grown under controlled conditions revealed a correlation (significant quantitative relationship) between dehydrin transcript/protein relative accumulation and plant frost tolerance. However, to apply these results in breeding, field experiments are necessary. The aim of the review is to provide a summary of the studies dealing with the relationships between plant acquired frost tolerance and COR/LEA transcripts/proteins relative accumulation in cereals grown in controlled and field conditions. The impacts of cold acclimation and vernalisation processes on the ability of winter-type Triticeae to accumulate COR/LEA proteins are discussed. The factors determining dehydrin relative accumulation under controlled cold acclimation treatments versus field trials during winter seasons are discussed. In conclusion, it can be stated that dehydrins could be used as suitable indicators of winter survival in field-grown winter cereals but only in plant prior to the fulfilment of vernalisation requirement.

scholarly journals Exploiting Thrips Aggregation Pheromones to Develop a Lure-and-Kill Strategy for the Management of the Bean Flower Thrips

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1269
Author(s):  
David K. Mfuti ◽  
Amanuel Tamiru ◽  
William D. J. Kirk ◽  
Adeyemi O. Akinyemi ◽  
Heather Campbell ◽  
...  
Keyword(s):  
Field Experiments ◽  
Insect Pests ◽  
Field Trials ◽  
Aggregation Pheromones ◽  
Megalurothrips Sjostedti ◽  
Flower Thrips ◽  
Antifungal Effects ◽  
Field Efficacy ◽  
Management Alternative ◽  
Trap Catches

The potential of semiochemicals to lure insect pests to a trap where they can be killed with biopesticides has been demonstrated as an eco-friendly pest management alternative. In this study, we tested two recently characterized male-produced aggregation pheromones of the bean flower thrips Megalurothrips sjostedti (Trybom), namely (R)-lavandulyl 3-methylbutanoate (major) and (R)-lavandulol (minor), for their field efficacy. Moreover, compatibility of these pheromones and two other thrips attractants, Lurem-TR and neryl (S)-2-methylbutanoate, with the entomopathogenic fungus (EPF) Metarhizium anisopliae ICIPE 69 has been determined. Our study revealed that the M. sjostedti aggregation pheromones have dose-dependent antifungal effects on the EPF viability, but showed no fungistatic effect at a field-realistic dose for attraction of thrips. (R)-lavandulyl 3-methylbutanoate had similar antifungal effects as neryl (S)-2-methylbutanoate 8 days after exposure; whereas, Lurem-TR had a stronger antifungal effect than other thrips attractants. In the semi-field experiments, all autoinoculation devices maintained at least 86% viability of M. anisopliae conidia after 12 days of exposure. Field trials demonstrated for the first time that (R)-lavandulyl 3-methylbutanoate increases trap catches. Our findings pave a way for designing a lure-and-kill thrips management strategy to control bean flower thrips using autoinoculation devices or spot spray application.

scholarly journals Synergistic Effect of Combined Application of a New Fungicide Fluopimomide with a Biocontrol Agent Bacillus methylotrophicus TA-1 for Management of Gray Mold in Tomato

Plant Disease ◽  
2019 ◽  
Vol 103 (8) ◽  
pp. 1991-1997 ◽  
Author(s):  
Xiaoxue Ji ◽  
Jingjing Li ◽  
Zhen Meng ◽  
Shouan Zhang ◽  
Bei Dong ◽  
...  
Keyword(s):  
Field Experiments ◽  
Biocontrol Agent ◽  
Severe Disease ◽  
Combined Treatment ◽  
Field Trials ◽  
Antimicrobial Activities ◽  
Gray Mold ◽  
Control Efficacy ◽  
Bacillus Methylotrophicus

Gray mold caused by Botrytis cinerea can be a severe disease of tomato infecting leaves and fruits of tomato plants. Chemical control is currently the most effective and reliable method; however, application of fungicides has many drawbacks. The combination of biological control agents with newly developed fungicides may be a practicable method to control B. cinerea. Fluopimomide is a newly developed fungicide with a novel mode of action. Bacillus methylotrophicus TA-1, isolated from rhizosphere soil of tomato, is a bacterial strain with a broad spectrum of antimicrobial activities. Little information is currently available about the effect of fluopimomide and its integrated effect on B. cinerea. Therefore, laboratory, pot, and field experiments were carried out to determine the effects of fluopimomide alone and in combination with B. methylotrophicus TA-1 against gray mold on tomato. The in vitro growth of B. methylotrophicus TA-1 was unaffected by 100 mg liter−1 fluopimomide. Inhibition of B. cinerea mycelial growth was significantly increased under combined treatment of fluopimomide and B. methylotrophicus TA-1. In greenhouse experiments, efficacy against gray mold was significantly greater by an integration of fluopimomide and B. methylotrophicus TA-1 than by either alone; control efficacy of fluopimomide at 50 and 100 g ha−1 in combination with B. methylotrophicus TA-1 at 108 colony-forming units (cfu) ml−1 reached 70.16 and 69.32%, respectively, compared with the untreated control. In both field trials during 2017 and 2018, control efficacy was significantly higher for the combination of fluopimomide at 50 and 100 g ha−1 in combination with B. methylotrophicus TA-1 than for either treatment alone. The results from this study indicated that integration of the new fungicide fluopimomide with the biocontrol agent B. methylotrophicus TA-1 synergistically increased control efficacy of the fungicide against gray mold of tomato.

Effects of irrigation regimes on powdery scab disease and yield of potatoes

1986 ◽  
Vol 26 (6) ◽  
pp. 745 ◽  
Author(s):  
PA Taylor ◽  
SP Flett ◽  
RFde Boer ◽  
D Marshall
Keyword(s):  
Large Scale ◽  
Field Experiments ◽  
Field Trials ◽  
Powdery Scab ◽  
Infested Soil ◽  
Spongospora Subterranea ◽  
Potato Tubers ◽  
Potato Plants ◽  
Tuber Set ◽  
Large Scale Field

The period of susceptibility of potato tubers to powdery scab (Spongospora subterranea) was studied by inoculating potato plants with spores, or by watering plants in infested soil, at different stages of plant development in greenhouse conditions. Maximum susceptibility began about 1 week before the stage when 50% of stolons had swollen to at least 5-mm diameter (tuber set), and ended 3-4 weeks later. With holding irrigation water during this period reduced the severity of powdery scab by 65-75% in field experiments in 1981-82 and 1982-83, but had no apparent effect on disease severity in 3 out of 6 large-scale field trials during 1984-85.

Management strategies to reduce losses caused by fusarium seedling blight of field pea

2013 ◽  
Vol 93 (4) ◽  
pp. 619-625 ◽  
Author(s):  
K. F. Chang ◽  
S. F. Hwang ◽  
H. U. Ahmed ◽  
B. D. Gossen ◽  
G. D. Turnbull ◽  
...  
Keyword(s):  
Root Rot ◽  
Field Experiments ◽  
Management Strategies ◽  
Stand Density ◽  
Field Trials ◽  
Field Pea ◽  
Seedling Blight ◽  
Inoculum Level ◽  
Fusarium Seedling Blight ◽  
Disease Pressure

Chang, K. F., Hwang, S. F., Ahmed, H. U., Gossen, B. D., Turnbull, G. D. and Strelkov, S. E. 2013. Management strategies to reduce losses caused by fusarium seedling blight of field pea. Can. J. Plant Sci. 93: 619–625. Fusarium seedling blight can cause substantial reductions in the stand density of field pea in western Canada. In greenhouse experiments, emergence decreased and root rot severity rose with increasing inoculum density. In field trials in 2007 and 2008 near Edmonton, AB, seeding at different depths and seeding dates did not consistently affect emergence or yield in Fusarium-infested soils. In field experiments, emergence declined significantly with each increase in inoculum level. Also, seed yield were reduced at high levels of disease pressure. Treatment of seed with Apron Maxx improved emergence, nodulation and yield of treatments challenged with inoculum of F. avenaceum in both greenhouse and field experiments. This research demonstrates the need to prevent seedling blight and root rot through proper seed treatment.

Impact of the biofungicide tetramycin on the development of Fusarium head blight, grain yield and deoxynivalenol accumulation in wheat

2020 ◽  
Vol 13 (2) ◽  
pp. 235-246
Author(s):  
W.Q. Shi ◽  
L.B. Xiang ◽  
D.Z. Yu ◽  
S.J. Gong ◽  
L.J. Yang
Keyword(s):  
Fusarium Head Blight ◽  
Fusarium Graminearum ◽  
Spore Germination ◽  
Field Experiments ◽  
Synergistic Effects ◽  
Field Trials ◽  
Head Blight ◽  
Mycelium Growth ◽  
Key Aspects

Fusarium graminearum causes Fusarium head blight (FHB), a devastating disease that leads to extensive yield and quality loss in wheat and barley production. Integrated pest management (IPM) is required to control this disease and biofungicides, such as tetramycin, could be a novel addition to IPM strategies. The current study investigated in vitro tetramycin toxicity in Fusarium graminearum and evaluated its effectiveness for the control of Fusarium head blight FHB. Tetramycin was shown to affect three key aspects of Fusarium pathogenicity: spore germination, mycelium growth and deoxynivalenol (DON) production. The in vitro results indicated that tetramycin had strong inhibitory activity on the mycelial growth and spore germination. Field trials indicated that tetramycin treatment resulted in a significant reduction in both the FHB disease index and the level of DON accumulation. The reduced DON content in harvested grain was correlated with the amount of Tri5 mRNA determined by qRT-PCR. Synergistic effects between tetramycin and metconazole, in both the in vitro and field experiments were found. Tetramycin could provide an alternative option to control FHB.

scholarly journals A NEW METHOD OF PERFORMING FIELD TRIALS

1969 ◽  
Vol 28 (1) ◽  
pp. 22-34
Author(s):  
Bernardo G. Capó
Keyword(s):  
Field Experiments ◽  
Field Tests ◽  
Field Trials ◽  
New Method ◽  
Numerical Example ◽  
Fertilizer Experiment ◽  
Treatment Experiment

A new method of performing field experiments with relatively small numbers of treatments is described. The requirement to be fulfilled by the layouts of such field tests is specified and examples of possible designs for a 5-treatment experiment are illustrated. The theory of the procedure of calculation is discussed and a numerical example of said calculations is furnished in connection with the interpretation of a fertilizer experiment performed with cotton.

Sign in / Sign up

Export Citation Format

Share Document