scholarly journals Rice False Smut Disease at Different Flowering Times

2016 ◽  
Vol 19 (2) ◽  
pp. 28-35 ◽  
Author(s):  
Bodrun Nessa ◽  
Moin U Salam ◽  
AHM Mahfuzul Haque ◽  
Jiban K Biswas ◽  
M Abdul Latif ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Flowering Time ◽  
Control Measure ◽  
Disease Incidence ◽  
First Record ◽  
Effective Control ◽  
Rice False Smut ◽  
Sunshine Hours ◽  
False Smut ◽  
The Relationship

CORRECTION: Due to a number of formatting and layout issues, the PDF of this paper was replaced on 10th October 2016. The page numbers of this article have changed from 28-34 to 28-35.Rice false smut (RFSm) has lately been recognized as an emerging disease worldwide. Its alarming prevalence in Bangladesh in the transplant Aman rice in the last three years has been widely reported. However, there is no effective control measure against the disease in this country. We hypothesized that manipulation of flowering time in aman rice may avoid RFSm incidence. A two-year study (2014 and 2015) during T. Aman season using the widely regarded RFSm-prone variety, BRRI dhan49, across a range of flowering regime from mid-July to mid-January, demonstrated lower disease incidence in earlier (till mid-October) and later (after mid-November) part. The highest incidence of the disease was recorded when the crop flowered on 9 and 5 November in 2014 and 2015, respectively. The disease was recorded on ratoons. The peak of the infection recorded on ratoons when flowered on 7 November. To the best of our knowledge, worldwide, this is the first record of the disease on ratoons. Rainfall did not influence the disease. The relationship between the disease incidence and relative humidity and sunshine hours were significant. Avoiding flowering time during mid-October to mid-November through planting time adjustment appeared as an effective practice to escape rice false smut disease incidence in Aman season.Bangladesh Rice j. 2015, 19(2): 28-35

scholarly journals Effect of meteorological parameters on Karnal bunt incidence in wheat under different agroclimatic zones of Punjab

2022 ◽  
Vol 24 (1) ◽  
Author(s):  
SARABJOT KAUR SANDHU ◽  
ANURAG ATTRI ◽  
RITU BALA
Keyword(s):  
Relative Humidity ◽  
Negative Correlation ◽  
Significant Positive Correlation ◽  
Meteorological Parameters ◽  
Disease Incidence ◽  
Karnal Bunt ◽  
Maximum Temperature ◽  
Wheat Crop ◽  
Sunshine Hours ◽  
Rainy Days

To quantify the effect of meteorological parameters on incidence of Karnal bunt in wheat crop, an investigation was done using 9 to 12 season’s data of Bathinda and Ludhiana stations of Punjab. Maximum temperature during March in range of 25-31oC, minimum temperature of February (8.5-11.0oC), morning and evening relative humidity of March in range of 85-95 and 40-60 per cent respectively, rainfall more than 25 mm with sunshine hours 5.5-9.0 hrs/day during mid February to mid March favour Karnal bunt in wheat crop. Maximum temperature of March showed significant negative correlation with incidence of Karnal bunt whereas minimum temperature of February showed significant positive correlation with disease incidence at both locations. Morning and evening relative humidity showed significant positive correlation with disease incidence. Rain amount and rainy days during mid February to mid March significantly influenced disease incidence. Sunshine hours had negative correlation with disease incidence. Backward multiple linear regression (BMLR) analysis indicated maximum temperature, rainfall and sunshine hours play significant role in Karnal bunt incidence at Ludhiana. However, at Bathinda, maximum temperature, evening time relative humidity, rain amount and rainy days played significant role.

scholarly journals Status of Rice False Smut Disease in Natore District of Bangladesh

2017 ◽  
Vol 20 (2) ◽  
pp. 31-37
Author(s):  
MM Sarker ◽  
AHMM Haque ◽  
B Nessa ◽  
MU Salam ◽  
MM Islam ◽  
...  
Keyword(s):  
Yield Loss ◽  
Disease Incidence ◽  
Rice False Smut ◽  
Fungicide Application ◽  
Significant Difference ◽  
The World ◽  
The Status ◽  
History Of ◽  
False Smut ◽  
Foliar Fungicide

Rice false smut has become an emerging disease across the world. Its incidence has become serious in Bangladesh during T. Aman season in the last five years. However, the status of the disease in farmer’s field has not been estimated in this country. This study included a survey of 90 fields in four unions of Natore district during ripening stage of T. Aman rice of 2015 in order to estimate the disease incidence, number of smut balls per infected panicle and yield loss, and to ascertain effectiveness of farmer’s unregistered foliar fungicide application. The results show that across the fields, disease incidence, number of smut balls per infected panicle and yield loss were 8.06±2.02%, 2.88±0.17 and 0.72±0.18% (± is 95% confidence interval), respectively. Disease incidence (18.71±5.18%), number of smut balls per infected panicle (3.51±0.39) and yield loss (1.75±0.38%) was the highest in Ramananda Khajura union compared to the other three unions surveyed. Among the varieties, BRRI dhan49 incurred the highest disease incidence (18.71±5.18%). The number of smut balls per infected panicle (3.51±0.39) and yield loss (1.75±0.38%) were also the highest in this variety. The crops which flowered during mid October to early November showed significantly higher disease incidence than early flowering crops. Application of unregistered foliar fungicides tended to have reduced the disease, but did not show significant difference with ‘no fungicide application’. It is concluded that the strategic management of the disease may be directed to the specific areas of the fields where there is a history of the disease through manipulating genotypes and transplanting time. Farmers should be cautious on adopting chemical option as there is no registered fungicide yet in Bangladesh for tactical management of the disease.Bangladesh Rice j. 2016, 20(2): 31-37

scholarly journals Weather Condition, Seasonal Variation and Ball Development Pattern in Relation to Rice False Smut Disease in Bangladesh

2019 ◽  
Vol 22 (1) ◽  
pp. 57-64
Author(s):  
B Nessa ◽  
MU Salam ◽  
AHMM Haque ◽  
MA Kashem ◽  
MS Kabir
Keyword(s):  
Disease Incidence ◽  
Weather Condition ◽  
Management Options ◽  
Local Conditions ◽  
Emergence Period ◽  
Rice False Smut ◽  
Average Temperature ◽  
Growing Seasons ◽  
False Smut ◽  
Weather Parameters

Rice false smut (RFSm) is an international disease. The effect of the disease has become seriously evident in Bangladesh since 2010. The disease is predominant in the country in the ‘T. Aman’ rice growing season. Its occurrence in other rice growing seasons not well studied and recorded. Information on driving weather variable(s) causing the disease epidemic is scanty and not ground-truthed. This study, conducted in the experimental farm of the Bangladesh Rice Research Institute, Gazipur, Bangladesh, attempted to fill those information gaps. The association of disease incidence and weather parameters such as relative humidity, cloud hour and rainfall, was inconsistence except for the daily average temperature. High disease incidence occurred when the average temperature during panicle emergence period ranged between 22-27°C; any temperature below or above the range linearly decreased the disease incidence. RFSm disease was recorded in the study area in all the months, except for in February and March. The distribution in the incidence of disease in the three rice growing seasons followed the order of ‘T. Aman’ > ‘Aus’ > ‘Boro’; it was ~ six times less in ‘Aus’ and ~ eight times less in ‘Boro’ season, compared to ‘T. Aman’ season. New balls formed on infected panicles in batch by batch. High number of such batches formed in ‘T. Aman’ season. The final status of the disease in an infected crop was the accumulation of incidence of the disease in each batch. This study provided key epidemiology on the development of RFSm in nature and it is concluded such information on the disease under local conditions would be the key to designing management options. Bangladesh Rice j. 2018, 22(1): 57-64

scholarly journals A novel six-phage cocktail reduces Pectobacterium atrosepticum soft rot infection in potato tubers under simulated storage conditions

2019 ◽  
Vol 366 (Supplement_1) ◽  
pp. i97-i104
Author(s):  
Alexander Byth Carstens ◽  
Amaru Miranda Djurhuus ◽  
Witold Kot ◽  
Lars Hestbjerg Hansen
Keyword(s):  
Pathogenic Bacteria ◽  
Control Measure ◽  
Disease Incidence ◽  
Soft Rot ◽  
Potato Production ◽  
Storage Conditions ◽  
Effective Control ◽  
Pectobacterium Atrosepticum ◽  
Isolation And Characterization ◽  
Phage Cocktail

ABSTRACT Pectobacterium atrosepticum is a species of plant pathogenic bacteria responsible for significant losses in potato production worldwide. Pectobacterium atrosepticum can cause blackleg disease on potato stems as well as the tuber disease termed potato soft rot. Methods for the effective control of these diseases are limited and are primarily based on good agricultural practices. Bacteriophages, viruses of bacteria, could be used as an alternative, environmentally friendly, control measure. Here, we describe the isolation and characterization of 29 phages virulent to P. atrosepticum. The phages belong to 12 different species based on a 95% sequence identity cut-off. Furthermore, based on sequence diversity and propagation results, we selected six of these phages to form a phage cocktail. The phages in the cocktail was tested on a number of P. atrosepticum strains in order to determine their host range. The phages was found to lyse 93% of the tested strains. The cocktail was subsequently tested for its effectiveness in combatting potato soft rot under simulated storage conditions. Use of the phage cocktail reduced both disease incidence and disease severity by 61% and 64%, respectively, strongly indicating that phage biocontrol has the potential to reduce the economic impact of soft rot in potato production.

scholarly journals Seed Contamination Thresholds for Development of Carrot Bacterial Blight Caused by Xanthomonas campestris pv. carotae

Plant Disease ◽  
1998 ◽  
Vol 82 (11) ◽  
pp. 1271-1275 ◽  
Author(s):  
K. C. Umesh ◽  
R. M. Davis ◽  
R. L. Gilbertson
Keyword(s):  
Relative Humidity ◽  
Daucus Carota ◽  
Bacterial Blight ◽  
Xanthomonas Campestris ◽  
Disease Incidence ◽  
Contamination Levels ◽  
The Relationship ◽  
Field Plots

The relationship between levels of carrot (Daucus carota subsp. sativus) seed contamination with Xanthomonas campestris pv. carotae and (i) establishment of populations of X. campestris pv. carotae on carrot leaves and (ii) the incidence and severity of carrot bacterial blight was determined in field plots in Davis, California, in 1995 and 1996. Levels of seed contamination ranged from 0 to 1.5 × 105 CFU/g in 1995 and from 0 to 1.5 × 107 CFU/g in 1996. Seed contamination levels were positively correlated with X. campestris pv. carotae populations detected on leaves and with the incidence and severity of carrot bacterial blight. The size of X. campestris pv. carotae populations on leaves was also directly related to disease incidence. In 1996, yields were significantly reduced in plots established with seed lots having the highest levels of X. campestris pv. carotae contamination. Under the conditions of this study (i.e., a location having low rainfall and relative humidity), the threshold of seed contamination for the establishment of X. campestris pv. carotae populations on leaves and for the development of carrot bacterial blight was unexpectedly high: 104 to 105 CFU/g of seed.

scholarly journals Research on Advance of Rice False Smut Ustilaginoidea virens (Cooke) Takah Worldwide: Part I. Research Status of Rice False Smut

2019 ◽  
Vol 11 (15) ◽  
pp. 240
Author(s):  
Shiwen Huang ◽  
Lianmeng Liu ◽  
Ling Wang ◽  
Yuxuan Hou
Keyword(s):  
Climatic Conditions ◽  
Economic Losses ◽  
Common Disease ◽  
Ustilaginoidea Virens ◽  
Cultivation System ◽  
Rice False Smut ◽  
Governmental Agencies ◽  
False Smut ◽  
The Relationship ◽  
Yield Decrease

Since hybrid rice was planted, rice false smut (RFS) caused by Ustilaginoidea virens (Cooke) Takah has risen from a sporadic secondary disease to a major devastating and common disease, due to the changes in climatic conditions, cultivation system, fertilization and water management and cultivar replacement, and has become one of the new three major rice diseases in China. In addition to cause rice yield decrease and economic losses, RFS also causes toxic effects on humans and animals, due to the fact that the pathogen has color, produces toxins, affects rice appearance, and reduces rice quality. Therefore, RFS has attracted great attention from various governmental agencies, research institutions and scientists. More than 300 papers related to RFS composed over the past 100 years were reviewed. In this part, the occurrence, epidemiology of RFS, the relationship between occurrence sverity of RFS and yield loss, field distribution pattern and sampling method of RFS and disease severity classification were discussed.

EL NINO RELATED CLIMATE AND DENGUE FEVER CASES IN JEDDAH, SAUDI ARABIA

2019 ◽  
Vol 25 (1) ◽  
Author(s):  
MASROOR ALI KHAN ◽  
KHALID AL GHAMDI ◽  
JAZEM A. MEHYOUB ◽  
RAKHSHAN KHAN
Keyword(s):  
Relative Humidity ◽  
Dengue Fever ◽  
El Niño ◽  
Significant Relationship ◽  
El Nino ◽  
Climate Data ◽  
Light Traps ◽  
Mosquito Abundance ◽  
Dengue Transmission ◽  
The Relationship

The focus of this study is to find the relationship between El Nino and dengue fever cases in the study area.Mosquito density was recorded with the help of light traps and through aspirators collection. Climate data were obtained from National Meteorology and Environment centre. (Year wise El Nino and La Nina data are according to NOAA & Golden Gate Weather Services). Statistical methods were used to establish the correlation coefficient between different factors. A high significant relationship was observed between Relative Humidity and Dengue fever cases, but Aedes abundance had no significant relationship with either Relative humidity and Temperature. Our conclusion is that the El Nino does not affect the dengue transmission and Aedes mosquito abundance in this region, which is supported by earlier works.

Control of Bulking in an Extended Aeration Sewage Treatment Plant

1972 ◽  
Vol 7 (1) ◽  
pp. 13-20
Author(s):  
D.D.P. Cane ◽  
G.J. Farguhar
Keyword(s):  
Dissolved Oxygen ◽  
Control Measure ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Effective Control ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Mixed Liquor ◽  
Air Supply

Abstract A case of filamentous activated sludge bulking was investigated at an extended aeration plant treating wastes from a highway service centre. The purpose of the study was to find an effective control measure for the bulking and, if possible, to determine the cause of the bulking condition. Experiments were conducted to determine the effects upon bulking of: (a) a controlled copper dosage to the mixed liquor, (b) variations in the organic loading rate, and (c) maintenance of high and low dissolved oxygen concentrations in the mixed liquor. The microorganism responsible for the bulking condition was tentatively identified as Sphaerotilus natans. Extensive growths of these bacteria occurred in the sludge when the mixed liquor dissolved oxygen concentration dropped below 0.5 mg/1. Such dissolved oxygen levels had frequently occurred at this plant due to the use of timed aeration cycles and the use of insufficient air supply during peak loading periods. Variations in organic loading rates were found to have no adverse effect on sludge settleability. When bulking was slight, the condition could be improved by increasing the dissolved oxygen level to 1.5 mg/1, or more. The rate at which the filamentous growths could be eliminated from a highly filamentous sludge by increased aeration was very slow, but could be greatly increased by the simultaneous feeding of copper to the mixed liquor at a dosage rate of 1.0 mg/1, based on the raw sewage flows.

Characterizing the effectiveness of COVID-19 mitigation measures: A data-centric approach (Preprint)

2020 ◽  
Author(s):  
Lukman Olagoke ◽  
Ahmet E. Topcu
Keyword(s):  
Control Measure ◽  
Control Measures ◽  
World Health ◽  
Mitigation Measures ◽  
Effective Control ◽  
The World ◽  
Decision Making Processes ◽  
And Performance ◽  
Health Organization ◽  
The Impact

BACKGROUND COVID-19 represents a serious threat to both national health and economic systems. To curb this pandemic, the World Health Organization (WHO) issued a series of COVID-19 public safety guidelines. Different countries around the world initiated different measures in line with the WHO guidelines to mitigate and investigate the spread of COVID-19 in their territories. OBJECTIVE The aim of this paper is to quantitatively evaluate the effectiveness of these control measures using a data-centric approach. METHODS We begin with a simple text analysis of coronavirus-related articles and show that reports on similar outbreaks in the past strongly proposed similar control measures. This reaffirms the fact that these control measures are in order. Subsequently, we propose a simple performance statistic that quantifies general performance and performance under the different measures that were initiated. A density based clustering of based on performance statistic was carried out to group countries based on performance. RESULTS The performance statistic helps evaluate quantitatively the impact of COVID-19 control measures. Countries tend show variability in performance under different control measures. The performance statistic has negative correlation with cases of death which is a useful characteristics for COVID-19 control measure performance analysis. A web-based time-line visualization that enables comparison of performances and cases across continents and subregions is presented. CONCLUSIONS The performance metric is relevant for the analysis of the impact of COVID-19 control measures. This can help caregivers and policymakers identify effective control measures and reduce cases of death due to COVID-19. The interactive web visualizer provides easily digested and quick feedback to augment decision-making processes in the COVID-19 response measures evaluation. CLINICALTRIAL Not Applicable

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