White blister disease control in radish seed crops

Albugo candida is a significant pathogen of many brassica species causing leaf spotting but, more importantly, hypertrophy of flowering stems (“stagheads”) resulting in yield loss. No chemicals are currently registered for white blister control in New Zealand. Little research has been carried out on white-blister management. The implications of seed transmission and subsequent disease expression in radish are not fully understood and control has relied on products containing metalaxyl-m+mancozeb. A range of fungicides were evaluated in two field trials and a pot trial for both efficacy against the disease and effect on radish yield. While metalaxyl-m+mancozeb improved yields in field trials and provided good disease suppression in pot trials, the fungicides azoxystrobin, boscalid+pyraclostrobin and cyazofamid were also equally effective or better than metalaxyl-m+mancozeb. Treatments were able to suppress leaf spotting by up to 90% and inflorescence infection by 50%. Seed yield increases of up to 67% were recorded. Potential new control options for white blister were identified providing alternatives to metalaxyl-m+mancozeb and thus contributing to an anti-resistance strategy.

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Sensitivity of Zasmidium citri-griseum to Fenbuconazole and Control of Citrus Greasy Spot in Panama

Agronomy ◽

10.3390/agronomy10101577 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1577

Author(s):

Vidal Aguilera-Cogley ◽

Antonio Vicent

Keyword(s):

Disease Control ◽

Fungicide Resistance ◽

Mycelial Growth ◽

Yield Loss ◽

Field Trials ◽

Effective Concentration ◽

Yield Reduction ◽

Reduce Risk ◽

And Control ◽

Reduce Disease Severity

Citrus greasy spot, caused by Zasmidium citri-griseum ( = Mycosphaerella citri) is the most prevalent fungal disease of citrus in Panama, causing premature defoliation and yield reduction. Fungicide applications are generally needed for the control of greasy spot. In this study, the sensitivity to fenbuconazole of 34 isolates of Z. citri-griseum from Panama was determined by calculating the effective concentration needed to reduce mycelial growth by 50% (EC50). Two field trials were conducted from 2011 to 2013, to evaluate the efficacy of fenbuconazole to reduce disease severity and yield loss. The EC50 values for fenbuconazole ranged from 0.09 to 7.62 μg mL−1, with a mean EC50 value of 2.66 ± 0.36 SE μg mL−1 for mycelial growth. These data can be used for monitoring sensitivity shifts in Z. citri-griseum to fenbuconazole and reduce risk of fungicide resistance in Panama. In the field trials, sprays with fenbuconazole significantly reduced (p < 0.0001) the severity of greasy spot on leaves compared with the non-treated control. Greater disease control was obtained when three sprays of fenbuconazole were applied instead of one. Nevertheless, no significant differences (p > 0.05) were detected in yield.

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Evaluation of Harvest-Aid Herbicides as Desiccants in Lentil Production

Weed Technology ◽

10.1614/wt-d-16-00007.1 ◽

2016 ◽

Vol 30 (3) ◽

pp. 629-638 ◽

Cited By ~ 5

Author(s):

Ti Zhang ◽

Eric N. Johnson ◽

Christian J. Willenborg

Keyword(s):

Adverse Effects ◽

Crop Yield ◽

Seed Yield ◽

Yield Loss ◽

Field Trials ◽

Growth Stages ◽

Yield And Quality ◽

Seed Field ◽

Dry Down ◽

General Reduction

Desiccants are currently used to improve lentil dry-down prior to harvest. Applying desiccants at growth stages prior to maturity may result in reduced crop yield and quality, and leave unacceptable herbicide residues in seeds. There is little information on whether various herbicides applied alone or as a tank-mix with glyphosate have an effect on glyphosate residues in harvested seed. Field trials were conducted at Saskatoon and Scott, Saskatchewan, Canada, from 2012 to 2014 to determine whether additional desiccants applied alone or tank mixed with glyphosate improve crop desiccation and reduce the potential for unacceptable glyphosate residue in seed. Glufosinate and diquat tank mixed with glyphosate were the most consistent desiccants, providing optimal crop dry-down and a general reduction in glyphosate seed residues without adverse effects on seed yield and weight. Saflufenacil provided good crop desiccation without yield loss, but failed to reduce glyphosate seed residues consistently. Pyraflufen-ethyl and flumioxazin applied alone or tank mixed with glyphosate were found to be inferior options for growers as they exhibited slow and incomplete crop desiccation, and did not decrease glyphosate seed residues. Based on results from this study, growers should apply glufosinate or diquat with preharvest glyphosate to maximize crop and weed desiccation, and minimize glyphosate seed residues.

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Field performance and early test results of offspring from two Norway spruce seed orchards containing clones transferred to warmer climates

Canadian Journal of Forest Research ◽

10.1139/x06-253 ◽

2007 ◽

Vol 37 (3) ◽

pp. 515-522 ◽

Cited By ~ 28

Author(s):

Tore Skrøppa ◽

Ketil Kohmann ◽

Øystein Johnsen ◽

Arne Steffenrem ◽

Øyvind M. Edvardsen

Keyword(s):

Norway Spruce ◽

Field Performance ◽

Seed Orchard ◽

Field Trials ◽

Climatic Conditions ◽

Test Results ◽

Seed Orchards ◽

Low Altitude ◽

Natural Stands ◽

Seed Crops

We present results from early tests and field trials of offspring from two Norway spruce ( Picea abies (L.) Karst.) seed orchards containing clones that have been transferred from high altitudes to sea level and from northern to southern latitudes. Seedlings from seeds produced in the low-altitude seed orchard developed frost hardiness later at the end of the growth season, flushed later in field trials, and grew taller than seedlings from seeds produced in natural stands. They had the lowest mortality rate and the lowest frequency of injuries in the field trials. Similar results were observed in seedlings from seeds produced in the southern seed orchard. We found no adverse effects of the changed growth rhythm. Seedlings from two seed crops in the southern orchard, produced in years with a warm and a cold summer, had different annual growth rhythms. The results are explained mainly by the effects of the climatic conditions during the reproductive phase. Seed crops from different years in the same seed orchard may produce seedlings that perform as if they were from different provenances. It is argued that the effects of the climatic conditions during seed production must contribute to the variation among provenances of Norway spruce.

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Characterization of Antagonistic Bacillus methylotrophicus Isolated From Rhizosphere and Its Biocontrol Effects on Maize Stalk Rot

Phytopathology ◽

10.1094/phyto-07-18-0220-r ◽

2019 ◽

Vol 109 (4) ◽

pp. 571-581 ◽

Cited By ~ 9

Author(s):

Xingkai Cheng ◽

Xiaoxue Ji ◽

Yanzhen Ge ◽

Jingjing Li ◽

Wenzhe Qi ◽

...

Keyword(s):

Biochemical Characterization ◽

Disease Incidence ◽

Field Trials ◽

Control Measures ◽

Disease Suppression ◽

Effective Control ◽

Stalk Rot ◽

Bacillus Methylotrophicus ◽

Transmission Electron ◽

Potential Biocontrol Agent

Stalk rot is one of the most serious and widespread diseases in maize, and effective control measures are currently lacking. Therefore, this study aimed to develop a new biological agent to manage this disease. An antagonistic bacterial strain, TA-1, was isolated from rhizosphere soil and identified as Bacillus methylotrophicus based on morphological and biochemical characterization and 16S ribosomal RNA and gyrB gene sequence analyses. TA-1 exhibited a strong antifungal effect on the growth of Fusarium graminearum mycelium, with 86.3% inhibition at a concentration of 108 CFU per ml. Transmission electron microscopy showed that TA-1 could disrupt the cellular structure of the fungus, induce necrosis, and degrade the cell wall. Greenhouse and field trials were performed to evaluate the biocontrol efficacy of TA-1 on maize stalk rot, and the results of greenhouse experiment revealed that the bacterium significantly reduced disease incidence and disease index. Seeds treated with a 108 CFU ml−1 cell suspension had the highest disease suppression at 86.8%. Results of field trials show that seed bacterization with TA-1 could not only reduce maize stalk rot incidence but also increase maize height, stem diameter, and grain yield. The lipopeptide antibiotics were isolated from the culture supernatants of TA-1 and identified as surfactins and iturins. Consequently, B. methylotrophicus TA-1 is a potential biocontrol agent against maize stalk rot.

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Bioefficacy of different insecticides against blister beetle Mylabris phalerata (Pallas) on pigeonpea

SAARC Journal of Agriculture ◽

10.3329/sja.v15i1.33151 ◽

2017 ◽

Vol 15 (1) ◽

pp. 55-65

Author(s):

AK Singh

Keyword(s):

Short Duration ◽

Untreated Control ◽

Yield Loss ◽

Population Abundance ◽

Neem Oil ◽

Net Return ◽

Maximum Productivity ◽

Lambda Cyhalothrin ◽

And Control ◽

Blister Beetle

The experiment was accomplished to evaluate the bioefficacy of different insecticides against Mylabris phalerata (Pallas) on pigeonpea. The experiment consisted of seven treatments viz., bifenthrin 62 g a.i. ha-1, lambda-cyhalothrin 24 g a.i. ha-1 (encapsulated with polymers; Matadore), chlorpyriphos 310 g a.i. ha-1+ cypermethrin 31 g a.i. ha-1, cypermethrin 62 g a.i. ha-1, neem oil 1500 ppm, permethrin 154 g a.i. ha-1, chloropyriphos 173 g a.i. ha-1 compared with untreated (control). The sixth day after each spray, minimum population abundance of M. phalerata and maximum percent efficacy in reducing their population was obtained from bifenthrin which was at par with lambda-cyhalothrin, cypermethrin, chlorpyriphos+ cypermethrin and permethrin and all these were significantly effective over chloropyriphos, neem oil and control plots. On the tenth day after each spray, minimum population abundance and highest per cent efficacy were obtained from bifenthrin which was at par with lambda-cyhalothrin and both these treatments were significantly superior over rest of the treatments. The maximum productivity was observed with bifenthrin, while highest net return per rupee investment was obtained from lambda-cyhalothrin treatment. The results explicitly show that out of all treatments, Lambda-cyhalothrin was effective and imposing lucrative against M. phalerata and thereby minimized the yield loss. Three sprays of lambda-cyhalothrin and bifenthrin with an interchange at ten days interval will be effectual and lucrative against M. phalerata in short duration pigeonpea crop.SAARC J. Agri., 15(1): 55-65 (2017)

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Efficacy of Clonostachys rosea strain ACM941 and fungicide seed treatments for controlling the root rot complex of field pea

Canadian Journal of Plant Science ◽

10.4141/p02-078 ◽

2003 ◽

Vol 83 (3) ◽

pp. 519-524 ◽

Cited By ~ 14

Author(s):

A. G. Xue

Keyword(s):

Root Rot ◽

Untreated Control ◽

Seedling Emergence ◽

Field Trials ◽

Field Pea ◽

Seed Treatments ◽

Clonostachys Rosea ◽

Pea Root ◽

Pea Root Rot ◽

Better Than

The efficacy of seed treatments with bioagent ACM941 (a strain of Clonostachys rosea), its formulated products GB116 and ACM941-Pro, and common fungicides for the control of pea root rot complex were examined in six field trials in western Canada from 1996 to 2000. The effects on seedling emergence, root rot severity, and yield varied among years. In trials 1 and 2 (1996–1997), none of the treatments significantly reduced root rot severity or increased yield. ACM941 + Thiram 75WP was the most effective treatment, increasing emergence by 17.4% and was significantly better than that of the untreated controls. In trials 3 and 4 (1997–1998), Apron FL alone and ACM941 + Apron FL were significantly better than the untreated control, increasing emergence by 6.2 and 7.7%, and yield by 10.8 and 11.5%, respectively. In trials 5 and 6 (1999–2000), AC M 941 and GB116 were equally the most effective treatments, increasing emergence by 11.5 and 12.2%, and yield by 8.2 and 6.3%, respectively. These effects were significantly greater than that of the untreated control, but not significantly different from those of Apron FL or Vitaflo-280. ACM941-Pro was developed and tested in 2000 only, and it increased emergence by 17.1% and reduced root rot severity by 29.6%. Key words: Bioagent, Clonostachys rosea, field pea, Pisum sativum, pea root rot complex (PRRC), seed treatment, fungicide

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New Cancer Stochastic Models Involving Both Hereditary and Nonhereditary Cancer Cases: A New Approach

ISRN Biomathematics ◽

10.1155/2013/954912 ◽

2013 ◽

Vol 2013 ◽

pp. 1-19

Author(s):

Wai-Yuan Tan ◽

Hong Zhou

Keyword(s):

Cancer Incidence ◽

Stochastic Models ◽

Biological Information ◽

Cancer Genes ◽

New Approach ◽

Human Cancers ◽

Seer Data ◽

Sampling Procedures ◽

And Control ◽

Better Than

To incorporate biologically observed epidemics into multistage models of carcinogenesis, in this paper we have developed new stochastic models for human cancers. We have further incorporated genetic segregation of cancer genes into these models to derive generalized mixture models for cancer incidence. Based on these models we have developed a generalized Bayesian approach to estimate the parameters and to predict cancer incidence via Gibbs sampling procedures. We have applied these models to fit and analyze the SEER data of human eye cancers from NCI/NIH. Our results indicate that the models not only provide a logical avenue to incorporate biological information but also fit the data much better than other models. These models would not only provide more insights into human cancers but also would provide useful guidance for its prevention and control and for prediction of future cancer cases.

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Fertility of inseminations with two sperm concentrations in oestrus-synchronized cattle

Animal Science ◽

10.1017/s0003356100016901 ◽

1973 ◽

Vol 17 (2) ◽

pp. 163-168

Author(s):

L. J. Boyd ◽

G. F. Smith ◽

P. D. P. Wood ◽

J. Craven ◽

D. R. Melrose ◽

...

Keyword(s):

Field Trials ◽

Return Rate ◽

Breeding Period ◽

Dairy Herds ◽

Dairy Heifers ◽

Melengestrol Acetate ◽

Beef Herds ◽

Live Sperm ◽

And Control

SUMMARYTwo field trials were conducted to evaluate oestrus synchronization under farm conditions and to determine if increased sperm numbers per insemination would enhance fertility at the first synchronized oestrus. One hundred and seventy-seven previously unmated British Friesian females in 6 dairy herds and 236 suckler cows in 9 beef herds were used. Treated animals received 1·0 mg melengestrol acetate (MGA) daily for 14 days. Treated and control animals were inseminated with either 15 or 60 million sperm per first insemination.Oestrus was synchronized in 94% of the treated dairy heifers and 66% of the treated suckler cows. Oestrus detection by herdsmen appeared to be much less precise in suckler herds than in the dairy herds.First inseminations were given during a 21-day breeding period (commencing at withdrawal of MGA) to 97% of treated and 79% of control dairy heifers (P<0·01), and to 77% of the treated and 69% of the control suckler cows (P>0·05). On an average, first inseminations were given 10 days earlier to treated heifers and 7 days earlier to treated suckler cows than to their control counterparts. The 45-day non-return rate to first inseminations was 81% for control and 41% for treated dairy heifers (P< 0·001) and 69% for control and 46% for treated suckler cows (P>0·05).Oestrus-synchronized animals required significantly more services than control animals during a 30-day breeding period. However, there was no difference between treated and control animals in the non-return rate to one or more services given during the prescribed 30-day breeding period.Insemination with 15 or 60 million live sperm had no effect on the non-return rate of treated or control animals.

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THE EFFECTIVENESS OF REALISTIC MATHEMATICS EDUCATION TO IMPROVE STUDENTS’ MULTI-REPRESENTATION ABILITY

Infinity Journal ◽

10.22460/infinity.v8i1.p21-30 ◽

2019 ◽

Vol 8 (1) ◽

pp. 21 ◽

Cited By ~ 3

Author(s):

Muhtarom Muhtarom ◽

Nizaruddin Nizaruddin ◽

Farida Nursyahidah ◽

Nurina Happy

Keyword(s):

Mathematics Education ◽

Experimental Design ◽

Learning Process ◽

Realistic Mathematics Education ◽

Student Responses ◽

Realistic Mathematics ◽

Quasi Experimental ◽

And Control ◽

Essay Test ◽

Better Than

This research aimed to evaluate the effectiveness of Realistic Mathematics Education (RME) to improve students' multi-representation ability. A quasi-experimental design was used in this research. Sixty-four samples from the seventh-grade students of Junior School were randomly selected and divided into two classes: experimental class was treated using RME and control class was treated using conventional learning, with each class consisting of thirty-two students. The essay test was used to measure the multi-representation ability of students and the questionnaire was used to measure students' responses in RME learning. The data from the essay test were analyzed by N-Gain test and t-test in which normality and homogenity test were conducted previously, while the students' learning completeness and student responses were presented descriptive quantitative. The result of the research concluded that the multi-representation ability of students who get RME learning is better than the multi-representation ability in students who get conventional learning. 87.25% of students who get RME learning with the developed device have completed the KKM, and many students are very enthusiastic and interested in RME based learning, thus increasing their learning spirit in a learning process.

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IMPLEMENTATION OF MODEL-ELICITING ACTIVITIES TO IMPROVE THE ABILITY OF MATHEMATICAL PROBLEM SOLVING

(JIML) JOURNAL OF INNOVATIVE MATHEMATICS LEARNING ◽

10.22460/jiml.v1i3.p312-317 ◽

2018 ◽

Vol 1 (3) ◽

pp. 312 ◽

Cited By ~ 1

Author(s):

Rubaitun Rubaitun

Keyword(s):

Problem Solving ◽

Mathematical Problem ◽

Mathematical Problem Solving ◽

Homogeneity Test ◽

Problem Solving Skills ◽

Normality Test ◽

Model Eliciting Activities ◽

Class Viii ◽

And Control ◽

Better Than

This study aims to determine whether the improvement of students' mathematical problem solving skills that get the learning of Model-Eliciting Activities is better than students who get regular learning. Method in this research is experiment and research design pretest and postest in experiment and control class. The population in this study were all students of MTs Kota Cimahi. School samples were taken at random, and obtained by MTs Negeri Kota Cimahi. Then the sample is selected two class VIII at random class. The experimental class uses Model-Eliciting Activities, while the control class uses ordinary learning. The hypothesis in this research is the improvement of student solving abilities of MTs students in Cimahi whose learning using Model-Eliciting Activities is better than using ordinary learning. Research data obtained through the instrument of posttest mathematical problem solving ability. The posttest data is processed by normality test, homogeneity test, and two average difference test using SPSS (Statistical Product and Service Solution) software version 16.0 for Windows. The results showed that the improvement of problem solving ability of MTs students in Cimahi whose learning using Model-Eliciting Activities was better than those using ordinary learning.

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