Timing of fungicides in relation to calendar date, weather, and disease thresholds to control Rhizoctonia web blight on container-grown azalea

2012 ◽  
Vol 42 ◽  
pp. 273-280 ◽  
Author(s):  
Warren E. Copes ◽  
Austin Hagan ◽  
John Olive
Keyword(s):  
Calendar Date ◽  
Web Blight

scholarly journals Weather-Based Forecasting of Rhizoctonia Web Blight Development on Container-Grown Azalea

Plant Disease ◽  
2015 ◽  
Vol 99 (1) ◽  
pp. 100-105 ◽  
Author(s):  
Warren E. Copes
Keyword(s):  
Receiver Operating Characteristic ◽  
Roc Curve ◽  
Operating Characteristic ◽  
Maximum Temperature ◽  
Leaf Wetness ◽  
Practical Application ◽  
Single Model ◽  
Preventive Control ◽  
Calendar Date ◽  
Web Blight

The most reliable approach for timing fungicides to control Rhizoctonia web blight on container-grown azalea has been a fixed calendar date. The purpose of this study was to model periods when a preventive control could be applied in advance of significant increases in leaf blight intensity (LBI) in response to a daily accumulated risk value indicating conducive conditions of temperature (18 or more hours between 20 and 30°C when maximum temperature is less than 35°C), leaf wetness (16 or more hours), and/or rainfall (greater than 6.7 mm above the maximum daily irrigation). Analysis used weather measurements taken every 30 minutes from 11 site-year datasets from 2006 to 2011, and weekly or biweekly LBI assessments. Six developmental site-year datasets were analyzed using receiver operating characteristic (ROC) curve procedures to evaluate models. Only a single model predicted true positives and negatives significantly greater than a 50:50 probability. Subsequently, five site-year validation datasets were evaluated. Similar results were obtained from both the developmental and validation datasets, which produced ROC areas of 0.7715 (P = 0.0120) and 0.8393 (P = 0.0034), respectively. The practical application of weather-based forecasting for management of web blight in nurseries is discussed.

TEMPORAL GENERALIZATION WITH DOMAIN GENERALIZATION GRAPHS

1999 ◽  
Vol 13 (02) ◽  
pp. 195-217 ◽  
Author(s):  
D. J. RANDALL ◽  
H. J. HAMILTON ◽  
R. J. HILDERMAN
Keyword(s):  
Partial Order ◽  
Relational Databases ◽  
Formal Specifications ◽  
Temporal Data ◽  
Calendar Date ◽  
Temporal Generalization ◽  
Domain Generalization Graphs

This paper addresses the problem of using domain generalization graphs to generalize temporal data extracted from relational databases. A domain generalization graph associated with an attribute defines a partial order which represents a set of generalization relations for the attribute. We propose formal specifications for domain generalization graphs associated with calendar (date and time) attributes. These graphs are reusable (i.e. can be used to generalize any calendar attributes), adaptable (i.e. can be extended or restricted as appropriate for particular applications), and transportable (i.e. can be used with any database containing a calendar attribute).

scholarly journals Occurrence of Web Blight in Soybean Caused by Rhizoctonia sol ani AG-l(IA) in Korea

2005 ◽  
Vol 21 (4) ◽  
pp. 406-408 ◽  
Author(s):  
Wan-Gyu Kim ◽  
Sung-Kee Hong ◽  
Seong-Sook Han
Keyword(s):  
Web Blight

scholarly journals Reactions of Some Common Bean Cultivars to Rhizoctonia Web Blight

2019 ◽  
Vol 5 (2) ◽  
pp. 273-279
Author(s):  
Gülsüm Palacıoğlu ◽  
Harun Bayraktar ◽  
Göksel Özer
Keyword(s):  
Common Bean ◽  
Web Blight

scholarly journals Radiocarbon Dates from Jar and Coffin Burials of the Cardamom Mountains Reveal a Unique Mortuary Ritual in Cambodia's Late- to Post-Angkor Period (15th–17th Centuries AD)

Radiocarbon ◽  
2012 ◽  
Vol 54 (01) ◽  
pp. 1-22 ◽  
Author(s):  
Nancy Beavan ◽  
Sian Halcrow ◽  
Bruce McFadgen ◽  
Derek Hamilton ◽  
Brendan Buckley ◽  
...  
Keyword(s):  
Phnom Penh ◽  
Radiocarbon Dates ◽  
Mortuary Ritual ◽  
Island Southeast Asia ◽  
Calendar Date ◽  
Exposed Rock ◽  
15Th Century ◽  
Funerary Rituals ◽  
Time Period ◽  
Burial Rituals

We present the first radiocarbon dates from previously unrecorded, secondary burials in the Cardamom Mountains, Cambodia. The mortuary ritual incorporates nautical tradeware ceramic jars and log coffins fashioned from locally harvested trees as burial containers, which were set out on exposed rock ledges at 10 sites in the eastern Cardamom Massif. The suite of 2814C ages from 4 of these sites (Khnorng Sroal, Phnom Pel, Damnak Samdech, and Khnang Tathan) provides the first estimation of the overall time depth of the practice. The most reliable calendar date ranges from the 4 sites reveals a highland burial ritual unrelated to lowland Khmer culture that was practiced from cal AD 1395 to 1650. The time period is concurrent with the 15th century decline of Angkor as the capital of the Khmer kingdom and its demise about AD 1432, and the subsequent shift of power to new Mekong trade ports such as Phnom Penh, Udong, and Lovek. We discuss the Cardamom ritual relative to known funerary rituals of the pre- to post-Angkorian periods, and to similar exposed jar and coffin burial rituals in Mainland and Island Southeast Asia.

The brevity and severity of ‘Golden Age’ piracy trials

2019 ◽  
Vol 31 (4) ◽  
pp. 729-786 ◽  
Author(s):  
Joseph Gibbs
Keyword(s):  
Golden Age ◽  
High Volume ◽  
Conviction Rate ◽  
Legal Proceedings ◽  
Calendar Date ◽  
Large Numbers ◽  
Opening Statements

A sampling of piracy and piracy-related trials involving mainly English (later British) and colonial courts between 1670 and 1731 shows that from opening statements through deliberations they were rapid affairs, few extending beyond a single calendar date, and that on average they appear to have convicted about six of every 10 defendants who pleaded Not Guilty. That conviction figure is impacted by high-volume trials in 1700 and 1722 that acquitted relatively large numbers of defendants; eliminating these two trials from the mix yields a significantly higher conviction rate (about seven in 10) for those who pleaded Not Guilty. This article presents its sampling data, noting appropriate cautions, in the context of the era’s legal proceedings and practices.

Current Status and Prospect of Web Blight of Cowpea: A Review

2020 ◽  
Author(s):  
Priyanka . ◽  
Anand Kumar Meena ◽  
A.C. Mathur ◽  
R.K. Bagri ◽  
R.S. Sharma
Keyword(s):  
Insect Pests ◽  
Dry Weight ◽  
Current Status ◽  
Basal Portion ◽  
Necrotic Spots ◽  
Brown Centre ◽  
Blight Disease ◽  
Web Blight ◽  
Soil Level ◽  
Important Disease

Pulses in India have been considered as the poor man’s only source of protein. Among them Cowpea (Vigna unguiculata) is an important food legume which is also known as vegetable meat due to high amount of protein in the grain with better biological value on dry weight basis. Various factors viz., diseases and insect pests are mostly responsible for its low production. Among diseases, web blight caused by Rhizoctonia solani is one of the most important disease of cowpea. The web blight appears every year at varying intensity and causes heavy losses in yield. Web blight disease is most severe at seedling and vegetative stage. The disease is characterized by oval or spindle shaped brown black lesions having length ranging from 0.2-8 cm at soil level near collar region and girdling the basal portion of the stem and lesions developed by basidiospores of Thanatephorus cucumeris which are 2-4 mm in diameter, circular and appear as brown necrotic spots with light brown centre. Cob web like symptoms also noticed hence, the name web blight.

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