scholarly journals Evaluation of a Disease Warning System for Phomopsis Cane and Leaf Spot of Grape: A Field Study

Plant Disease ◽  
2006 ◽  
Vol 90 (9) ◽  
pp. 1239-1246 ◽  
Author(s):  
M. Nita ◽  
M. A. Ellis ◽  
L. L. Wilson ◽  
L. V. Madden
Keyword(s):  
Leaf Spot ◽  
Shoot Growth ◽  
Disease Incidence ◽  
Warning System ◽  
Field Evaluation ◽  
Weather Conditions ◽  
Relative Difference ◽  
Phomopsis Viticola ◽  
The Mean ◽  
Vitis Spp

A field evaluation of a warning system for Phomopsis cane and leaf spot of grape (Vitis spp.), caused by Phomopsis viticola, was conducted in Ohio over 3 years (2002 to 2004) by applying fungicides and fungicide-adjuvant combinations based on predicted infection events. Three different criteria for risk—light, moderate, and high—were evaluated with the warning system. The warning system is based on measured weather conditions (temperature and wetness duration following rain) and a model for risk of leaf and internode infection. Vines were sprayed with fungicides based on either the warning system or a calendar-based 7-day protectant program, from 2.5-cm shoot growth (Eichhorn-Lorenz [E-L] stage 7) to the end of the broom (E-L stage 27). Fungicides were tested with or without an adjuvant (JMS Stylet-Oil or Regulaid). In the controls, the mean percentage of leaves and internodes with infections ranged from 36 to 100%, the number of lesions per leaf ranged from 1 to 28, and percentage of internodes covered by lesions ranged from 1 to 12%. Both the calendar-based protectant treatment (based on use of mancozeb) and the warning system treatment based on spraying in response to light or moderate predicted infection events (especially with mancozeb + Regulaid) resulted in significantly less disease incidence and severity compared with the controls. The mean percent control (relative difference in disease between a treatment and the control) was higher for the protectant schedule (˜55% and ˜80% for incidence and severity, respectively, based on application of mancozeb) than for the warning system (˜36% and ˜60% for incidence and severity, respectively, based on application of mancozeb + Regulaid), but there were two to three times more fungicide applications with the protectant schedule than with the warning system.

scholarly journals Sources of variation in a field evaluation of the incidence and severity of olive leaf spot

2005 ◽  
Vol 58 ◽  
pp. 273-277 ◽  
Author(s):  
E.O. Obanor ◽  
M. Walter ◽  
E.E. Jones ◽  
M.V. Jaspers
Keyword(s):  
Leaf Spot ◽  
Disease Incidence ◽  
Field Evaluation ◽  
Leaf Spot Disease ◽  
Olive Leaf ◽  
Mean Values ◽  
Spot Disease ◽  
Sources Of Variation ◽  
The Mean ◽  
Over Time

Incidence ( infected leaves) and severity (number of lesions/leaf) of olive leaf spot disease caused by Spilocaea oleagina were assessed every 2 weeks on 20 trees in a Canterbury olive grove for 12 weeks during summer 2003/04 All the trees were infected by olive leaf spot disease (OLS) and although disease incidence and severity varied between trees (Plt;0001) it did not vary between branches over time (P0088) There was a strong correlation (R20869) between disease incidence and severity It was estimated that at least five trees and 50 leaves/tree were required to correctly estimate the mean values of the parameters measured Throughout the duration of the experiment no new leaf lesions formed and although old lesions increased in size (Plt;0001) spore numbers decreased from 5104 to 1102 conidia/cm2 of lesion and viability of conidia declined from 55 to 10

Evaluations of New and Current Management Strategies to Control Phomopsis Cane and Leaf Spot of Grape

2007 ◽  
Vol 8 (1) ◽  
pp. 69 ◽  
Author(s):  
Mizuho Nita ◽  
Michael A. Ellis ◽  
Leslie L. Wilson ◽  
Laurence V. Madden
Keyword(s):  
Leaf Spot ◽  
Early Stage ◽  
Disease Incidence ◽  
Management Strategies ◽  
Warning System ◽  
Weather Conditions ◽  
Early Spring ◽  
System Control ◽  
Stage Of Development ◽  
Significant Difference

To extend our understanding of the epidemiology and control of Phomopsis cane and leaf spot of grape, caused by Phomopsis viticola, studies were conducted to: (i) determine efficacy of a dormant fungicide spray program for controlling the disease in its early stage of development (e.g., spring); (ii) evaluate a disease warning system by applying fungicides and fungicide-adjuvant combinations in response to predicted infection periods based on weather conditions; and (iii) correlate commercial control practices and environmental conditions with disease incidence based on a state-wide survey of commercial fields. With the warning system, control was equal to that obtained with a 7-day protectant fungicide program, but with fewer fungicide applications per season. A dormant application provided consistent, yet only moderate, control of the disease. Growers who applied a dormant-season application or early spring protectant fungicides tended to have lower disease incidence than those who did not. There was high variability in disease incidence within vineyards and farms, but no significant difference in incidence among regions of the state. Overall, early season application of protective fungicides was shown to be a key factor for successful management of P. viticola. Accepted for publication 29 March 2007. Published 26 July 2007.

scholarly journals Screening of French Bean (Phaseolus vulgaris L.) Genotypes against Alternaria Leaf Spot Caused by (Alternaria alternata) under Dryland Conditions of Kashmir

2021 ◽  
pp. 25-30
Author(s):  
Sabiya Bashir ◽  
Mohammad Najeeb Mughal ◽  
Zahida Rashid ◽  
Shabeena Majid ◽  
Sabeena Naseer ◽  
...  
Keyword(s):  
Alternaria Alternata ◽  
Leaf Spot ◽  
Disease Incidence ◽  
French Bean ◽  
Phaseolus Vulgaris L ◽  
Dryland Agriculture ◽  
Disease Reaction ◽  
The Mean ◽  
Selection For ◽  
Resistant Genotypes

Sixty-three genotypes of  french bean was screened against leaf spot (Alternaria  alternata) in sick plots at Research Farm of Dryland Agriculture Research Srinagar, Rangreth during  Kharif  2018 and 2019. The highest mean disease incidence ranged from 0.00 to 85.00 per cent  with  the mean disease intensity ranged from 0.00 to 53.26 per cent .One genotype namely  ‘Local Pulwama’ was highly susceptible in their disease reaction. Among the screened germplasm, ‘Highly Resistant’ genotypes was SKU-R-601, SKUA-R-105, SKU-R-927, DARS-25, DARS-66, DARS-R-615,  while as ‘Susceptible’ genotypes was  DARS-8, DARS-12,  DARS-11, SKUAST-R-155, SKU-R-928, DARS-7, DARS-R-4, Bhaderwah (L),  Local  Kupwara black and Raj Jawala. Local Pulwama was found to be a highly susceptible (HS) genotype.  Twenty nine genotypes namely., DARS-16, DARS-9, DARS-54, DARS-39, VL-125, DARS-63, ENTO-504, SKUAST-204,SKU-R-925, DARS-60, DARS-109, DARS-43, DARS-44, SKU-R-23, DARS-4, DARS-74, SKU-R-105, DARS-40, DARS-23, DARS-18, SKU-R-71, WB-341, SKU-R-605, Uri local, Shopian (L), SKU-R-23, DARS-71, SSGB-729, DARS-R-19 showed resistant reaction to disease. The selection for resistance was based on the reaction of varieties on leaves.

scholarly journals Temporal Patterns of Sporulation Potential of Phomopsis viticola on Infected Grape Shoots, Canes, and Rachises

Plant Disease ◽  
2012 ◽  
Vol 96 (9) ◽  
pp. 1297-1302 ◽  
Author(s):  
D. J. Anco ◽  
L. V. Madden ◽  
M. A. Ellis
Keyword(s):  
Leaf Spot ◽  
Temporal Pattern ◽  
Growing Season ◽  
First Year ◽  
Bud Break ◽  
Optimal Conditions ◽  
Phomopsis Viticola ◽  
Time Period ◽  
Dormant Season ◽  
Vitis Spp

Phomopsis cane and leaf spot on Vitis spp. (grape) is currently understood to be monocyclic, with primary inoculum only being produced early in the growing season. However, of the few published studies pertaining to sporulation of Phomopsis viticola, none specifically examined rachises, and none were designed to determine when infected tissues become capable of sporulation. The objective of these studies was to determine when grape shoots, canes, and rachises infected with P. viticola develop the capacity to sporulate, and to determine the time period during which those tissues remain capable of sporulation. Starting in 2009 and 2010, infected first-year shoots and rachises were collected biweekly throughout the growing season, into the dormant season, and into the following growing season. Tissues were collected from ‘Catawba,’ ‘Concord,’ and ‘Reliance’ vineyards. Samples were observed for sporulation after 48 h of incubation in a moist chamber at 23°C; the magnitude of the conidia production under these optimal conditions was considered the sporulation potential. For infections that occurred in 2009 and 2010, the production of conidia was not observed until after harvest. In the year following infection, sporulation potential was found from about bud break until shortly after the end of bloom. There was a generally consistent temporal pattern to relative sporulation potential across sampled vineyards, years, and grape tissues (rachises and canes), described by a modified β model, with peak sporulation potential occurring around 16 May. These results confirmed that Phomopsis cane and leaf spot is a monocyclic disease and support control recommendations for use of fungicides in spring.

scholarly journals SUSCEPTIBILITY OF LEMON BALM (Melissa officinalis L.) VARIETIES TO SEPTORIA LEAF SPOT (Septoria melissae Desm.) IN HUNGARY

2019 ◽  
Vol 18 (1) ◽  
pp. 47-56
Author(s):  
Gergő Kovács ◽  
Éva Zámbori-Németh ◽  
Géza Nagy
Keyword(s):  
Leaf Spot ◽  
Plant Protection ◽  
Disease Incidence ◽  
Weather Conditions ◽  
The Other ◽  
Melissa Officinalis ◽  
Lemon Balm ◽  
Protection Method ◽  
Cultivated Plant ◽  
Septoria Leaf Spot

Lemon balm (Melissa officinalis L.) is a widely cultivated plant in Europe. Septoria melissae Desm. is the most important pathogen of lemon balm crops, which may cause serious yield loss by the severe leaf fall. As chemical control of the pathogen is restricted, alternative plant protection methods, like the use of tolerant varieties, should be taken under consideration. The goal of our work was to evaluate the susceptibility of three lemon balm varieties to Septoria leaf spot in field. The trials were carried out in 2016 and 2017 in Budapest-Soroksár, Hungary. Dynamics of infection showed characteristic sharp increase from the beginning of August in both years. The lowest infection levels were observed in cultivar ‘Lemona’. The disease incidence in the middle of August was 19% in the first year and 59% in the second year, while these values were over 40% and 70% in the other cultivars ‘Soroksári’ and ‘Quedlinburger Niederliegende’, respectively. The manifestation of symptomps was also significantly lighter on the ‘Lemona’ plants and they had the highest ratio of healthy leaves (81%) compared to the other cultivars. According to the data, weather conditions might modify the range of the differences among the cultivars. It was concluded that appropriate selection of varieties could be an effective and enviromental friendly plant protection method in the practice of lemon balm cultivation.

scholarly journals Effects of Application of Fungicide During the Dormant Period on Phomopsis Cane and Leaf Spot of Grape Disease Intensity and Inoculum Production

Plant Disease ◽  
2006 ◽  
Vol 90 (9) ◽  
pp. 1195-1200 ◽  
Author(s):  
M. Nita ◽  
M. A. Ellis ◽  
L. L. Wilson ◽  
L. V. Madden
Keyword(s):  
Leaf Spot ◽  
Disease Incidence ◽  
Lower Number ◽  
Rain Water ◽  
First Year ◽  
Tissue Formation ◽  
Dormant Period ◽  
Phomopsis Viticola ◽  
Growing Seasons ◽  
Calcium Polysulfide

Efficacy of application of the fungicides calcium polysulfide or fixed copper during the dormant period on control of Phomopsis cane and leaf spot of grape (Vitis spp.), caused by Phomopsis viticola, was examined under field conditions during the 2003 and 2004 growing seasons in Ohio. Dormant-period fungicide applications were made either in the fall (after leaf drop and periderm tissue formation on the first-year canes, mid-November), or spring (at bud-swell, mid-April), or both. Disease incidence and severity on leaves and internodes were examined. In addition, effects of dormant-period application on sporulation of P. viticola were determined by examining the number of conidia in rain-splashed water in the spring and formation of mature pycnidia on cane sections in the winter. Fall-and-spring and spring applications of calcium poly-sulfide provided 12 to 88% reduction in disease intensity (incidence or severity), whereas calendar-based protectant mancozeb applications reduced overall disease intensity by 47 to 100%. Fixed-copper applications did not provide a consistent reduction of the disease. Fall applications of dormant-period fungicide provided little or no effect by itself. There was a significantly lower number of conidia observed in collected splashed rain water from vines treated with fall-and-spring applications of calcium polysulfide than in rain water from nonsprayed vines. Fall-and-spring and spring applications of calcium polysulfide provided a significant reduction in the number of mature pycnidia formed on incubated cane sections compared with the nonsprayed control (5 versus 10 pycnidia/cm2), whereas fixed copper did not provide a significant reduction.

The bioactivity and efficacy of benzovindiflupyr against Corynespora cassiicola, the causal agent of cucumber Corynespora leaf spot

Plant Disease ◽  
2021 ◽  
Author(s):  
Jiamei Zhu ◽  
Xiuhuan Li ◽  
Lingyan Zhang ◽  
Yangyang Gao ◽  
Wei Mu ◽  
...  
Keyword(s):  
Leaf Spot ◽  
Integrated Management ◽  
Disease Incidence ◽  
Field Trials ◽  
Corynespora Cassiicola ◽  
Atp Production ◽  
Control Failure ◽  
Efficient Alternative ◽  
The Mean ◽  
And Control

Corynespora cassiicola, which causes Corynespora leaf spot, results in considerable yield loss of cucumber grown in greenhouses. Frequent reports of reduced efficacy and control failure of fungicides warrant new, efficient alternative chemistries. In the present study, the sensitivity of C. cassiicola to benzovindiflupyr was evaluated using a collection of 81 isolates collected from Shandong, China. The mean EC50 values for mycelial growth, spore germination and germ tube elongation of C. cassiicola were 0.69 ± 0.44, 0.12 ± 0.063 and 0.13 ± 0.076 µg mL-1, respectively. Benzovindiflupyr treatment led to a reduced respiration rate and ATP production of C. cassiicola and decreased spore pathogenicity by 21.9% on average. Additionally, detached cucumber leaves sprayed with fungicides before or after inoculation were used to assess the efficacy of benzovindiflupyr against C. cassiicola. Benzovindiflupyr (150 µg mL-1) exhibited preventive and curative efficacies of 86.9% and 77.1%, respectively. Benzovindiflupyr at 150 g a.i. ha-1 provided over 70% efficacy in field trials performed in 2018 and 2019, which was significantly higher than that of the reference fungicides fluopyram and fluxapyroxad at the same dose. Furthermore, the yield of commercial cucumber increased as disease incidence decreased. Our findings pave the way for the introduction of benzovindiflupyr in the integrated management of Corynespora leaf spot.

Assessment of a water filtration device for household use in rural communities in Mexico

1997 ◽  
Vol 35 (11-12) ◽  
pp. 65-69 ◽  
Author(s):  
M. Galván ◽  
J. de Victorica
Keyword(s):  
Rural Communities ◽  
Gastrointestinal Disease ◽  
Disease Incidence ◽  
Field Evaluation ◽  
Epidemiological Studies ◽  
Poor Quality ◽  
Laboratory Conditions ◽  
Operation Conditions ◽  
Rural Mexico ◽  
Quality Water

Epidemiological studies in rural Mexico have shown the role of poor quality water in gastrointestinal disease incidence. This led to the establishment of a program, which included the assessment of inexpensive systems for household treatment of drinking water. We describe the main features of a hand carved stone filter evaluated over 6 months under laboratory conditions and 6 months under household conditions. The filter had a capacity of 5L and an average volume of 18L/d filtered water (the temperature of which was always an average 4°C lower than the influent). Average bacterial removals under laboratory conditions were 98% for total and faecal coliforms (TC, FC), 96% for faecal streptococci (FS), 99% for Pseudomonas aeruginosa and 100% for helminth eggs and protozoan cysts. During the field evaluation removals were 80–100% TC, 45–95% FC and 8–93% FS due to the different qualities of influent water and the operation conditions. Nevertheless, the filters represented an immediate mitigation measure of the health risks associated with the continuous ingestion of microbiologically unsafe waters.

scholarly journals Pilonidal sinus disease on the rise: a one-third incidence increase in inpatients in 13 years with substantial regional variation in Germany

2021 ◽  
Author(s):  
Christina Oetzmann von Sochaczewski ◽  
Jan Gödeke
Keyword(s):  
Pilonidal Sinus ◽  
Regional Variation ◽  
Disease Incidence ◽  
Age Groups ◽  
Pilonidal Sinus Disease ◽  
National Guidelines ◽  
Reconstructive Procedures ◽  
Sinus Disease ◽  
The Mean ◽  
Almost All

Abstract Purpose Collective evidence from single-centre studies suggests an increasing incidence of pilonidal sinus disease in the last decades, but population-based data is scarce. Methods We analysed administrative case–based principal diagnoses of pilonidal sinus disease and its surgical therapy between 2005 and 2017 in inpatients. Changes were addressed via linear regression. Results The mean rate of inpatient episodes of pilonidal sinus disease per 100,000 men increased from 43 in 2005 to 56 in 2017. In females, the mean rate of inpatient episodes per 100,000 women rose from 14 in 2005 to 18 in 2017. In the whole population, for every case per 100,000 females, there were 3.1 cases per 100,000 males, but the numbers were highly variable between the age groups. There was considerable regional variation within Germany. Rates of inpatient episodes of pilonidal sinus disease were increasing in almost all age groups and both sexes by almost a third. Surgery was dominated by excision of pilonidal sinus without reconstructive procedures, such as flaps, whose share was around 13% of all procedures, despite recommendations of the national guidelines to prefer flap procedures. Conclusion Rates of inpatient episodes of pilonidal sinus disease in Germany rose across almost all age groups and both sexes with relevant regional variation. The underlying causative factors are unknown. Thus, patient-centred research is necessary to explore them. This should also take cases into account that are solely treated office-based in order to obtain a full-spectrum view of pilonidal sinus disease incidence rates.

scholarly journals Potential Fertilization Capacity of Two Grapevine Varieties: Effects on Agricultural Production in Designation of Origin Areas in the Northwestern Iberian Peninsula

Agronomy ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 961
Author(s):  
J. Antonio Cortiñas Rodríguez ◽  
María Fernández-González ◽  
Estefanía González-Fernández ◽  
Rosa A. Vázquez-Ruiz ◽  
F. Javier Rodríguez-Rajo ◽  
...  
Keyword(s):  
Airborne Pollen ◽  
Germination Rate ◽  
Pollen Viability ◽  
Weather Conditions ◽  
Triphenyl Tetrazolium Chloride ◽  
Tetrazolium Chloride ◽  
The Mean ◽  
Study Sites ◽  
Fertilization Capacity

In the present study, we analyzed the main parameters related with the potential fertilization ability of two grapevine varieties, Godello and Mencía, during the years 2017 and 2018. The research was carried out in two vineyards of the Galician winegrowing Designation of Origin areas of Ribeiro and Ribeira Sacra. Ten vines of each variety were selected for bunch and flower counting, pollen calculations, pollen viability studies by means of aceto-carmine (AC) stain and 2, 3, 5-triphenyl tetrazolium chloride (TTC) methods, and the determination of their germination rate. In all vineyards the 50% fruitset was reached, except for Godello in Cenlle during 2017. The mean coulure value was higher for Godello (40.5%) than for Mencía (31%). Analyzing the pollen production per plant and airborne pollen levels, we observed important discordances between them, which can be due to the influence of weather conditions and be related with self-pollination processes. We found important differences on pollen viability depending on the applied method and variety, with higher values for the AC method than the TTC for both varieties in all study plots, and higher values for Mencía variety than Godello. Regarding germination rates, we observed a marked reduction in 2017 with respect to 2018, in all study sites and for both varieties. The analyzed parameters were useful to explain the different productive abilities of Godello and Mencía varieties in the two studied bioclimatic regions of Ribeiro and Ribeira Sacra.

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