scholarly journals Sugarcane Mosaic Distribution, Incidence, Increase, and Spatial Pattern in Louisiana

Plant Disease ◽  
2019 ◽  
Vol 103 (8) ◽  
pp. 2051-2056
Author(s):  
J. L. Rice ◽  
J. W. Hoy ◽  
M. P. Grisham
Keyword(s):  
Spatial Pattern ◽  
Disease Incidence ◽  
Aphid Transmission ◽  
Field Surveys ◽  
Reverse Transcription Pcr ◽  
Single Leaf ◽  
Disease Surveys ◽  
Low Incidence ◽  
Mosaic Distribution ◽  
Production Areas

Sugarcane mosaic is a historically important disease in Louisiana currently caused by sorghum mosaic virus (SrMV). Successful breeding for resistance reduced the disease to low incidence in commercial cultivars. However, mosaic was detected in experimental clone evaluations at multiple locations, leading to uncertainty concerning the current distribution and incidence in the state. Field surveys were conducted from 2016 to 2018 in breeding program yield trials and experimental clone seed cane increase fields. Mosaic symptomatic plants were observed in a newly released cultivar, HoCP 09-804, in three of five production areas, with incidences ranging from 0 to 10%. Mosaic also was observed in nine additional experimental clones. Single leaf samples were tested for SrMV using reverse transcription PCR. All symptomatic samples and a low percentage (0.3%) of asymptomatic samples tested positive for SrMV, confirming that it continues to be the causal species. Runs analysis detected aggregation of infected plants within at least 70% of rows in 94% of surveyed fields. The spatial pattern and geographical distribution of disease incidence suggested that infected seed cane was the source of the disease. Surveys conducted in the same fields of HoCP 09-804 through two subsequent crops detected disease incidence increases in some fields and decreases in the others in first ratoon, but observed incidence was lower compared with plant cane in all fields in second ratoon. The results indicated that disease increase owing to aphid transmission did not occur under the prevailing conditions.

scholarly journals Determining the Spatial Pattern of Blackleg Diseased Potato Plants in the Field and Simulated Post-Harvest Tuber Infections in Potato Crates

2021 ◽  
Author(s):  
Thomas H. Been ◽  
Johanna E. Beniers ◽  
Jan M. van der Wolf
Keyword(s):  
Spatial Pattern ◽  
Disease Incidence ◽  
Random Pattern ◽  
Field Surveys ◽  
Infected Seed ◽  
Seed Potatoes ◽  
Potato Plants ◽  
Global Positioning ◽  
Before And After ◽  
Random Distributions

Abstract Experiments were carried out in 2012 and 2013 to answer two basic questions in the testing of potato blackleg causing agents before and after harvest. Firstly, what is the spatial distribution of symptomatic plants in the field. Secondly, what is the distribution of infected tubers over the crates and the resulting detection probability using the standard method of collecting 200 tubers from the top crates in storage. In both years, ten farmers were equipped with a global positioning system (Garmin GPSMAP 62) and asked to register the position of blackleg diseased plants every time they scouted their potato lot for diseases. To answer the second question, potatoes marked with four nails (only visible internally after harvest) and potatoes with a different skin colour were added to one-hectare (ha) fields of seed potatoes in different patterns of aggregation ranging from random, to aggregated distribution, up to one big hotspot prior to harvest. The invisibly marked tubers were used for the unbiased collection of twenty 200-tuber samples from the storage crates, while the coloured skin tubers were used to ascertain, when the potatoes were graded, the distribution of ‘infected’ potatoes over the storage crates. The experiment was carried out with 0.05 and 0.1% disease incidence, in 2012 and 2013, respectively. Twenty two out of 26 fields proved to have a random pattern of diseased plants at harvest, which indicates that the blackleg diseased plants came into the field as infected seed potatoes. Two of the four aggregated patterns detected, started out as random distributions but became aggregated later in time, indicating spread in the field. A random spatial pattern in the field at harvest proved to result in a uniform distribution of infected tubers in the crates and, consequently, sampling of only the top crates for the 200-tuber sample does not introduce any bias. Fifty percent of the infected farmer lots were detected by the Nederlandse Algemene Keuringsdienst inspectors performing their official field surveys, which was a better performance than the 18% detection obtained by the standard 200-tuber sampling method. Only 6 out of 80 samples from the ‘infected’ lots with 0.05% disease incidence level, and 22 out of 80 samples at the 0.1% disease incidence level were detected by the latter method. It was concluded that intensifying the field survey would be cheaper and more successful than enlarging the tuber sample size to increase the probability for detection of infected seed lots.

scholarly journals First Report of Clover Proliferation Group Phytoplasmas (16SrVI-A) Associated with Purple Top Diseased Potatoes (Solanum tuberosum) in China

Plant Disease ◽  
2011 ◽  
Vol 95 (7) ◽  
pp. 871-871 ◽  
Author(s):  
M. Cheng ◽  
J. Dong ◽  
P. J. Laski ◽  
Z. Zhang ◽  
J. H. McBeath
Keyword(s):  
Nested Pcr ◽  
Disease Incidence ◽  
Restriction Enzymes ◽  
Potato Production ◽  
First Report ◽  
Growing Seasons ◽  
Pcr Product ◽  
Disease Surveys ◽  
Production Areas ◽  
Inner Mongolia Autonomous Region

Phytoplasma diseases on potatoes are not well understood and have gone largely undetected in China. During the growing seasons of 2005 through 2010, potato disease surveys were conducted in seed and commercial fields in Yunnan Province. Samples were also harvested from three seed potato production areas in the Inner Mongolia Autonomous Region in 2007 and 2010. Disease incidence in these fields ranged from 15 to 85%. Plants displayed symptoms of branch proliferation, aerial tuber formation, upward rolling yellowish and purplish apical leaves, and extremely short stolen or chain tubers (irregular-shaped tubers). Total DNA from 250 samples was extracted from the leaves, stems, and roots of symptomatic and asymptomatic plants. A nested PCR was performed by using primer pair P1/P7 followed by R16F2n/R16R2 to detect the presence of phytoplasmas (1,3). An approximate 1.2-kb PCR product was amplified from symptomatic plants but not from asymptomatic plants. Restriction fragment length polymorphism (RFLP) patterns were analyzed by digesting the 1.2-kb amplicon singly with restriction enzymes AluI, BfaI, MseI, HhaI, HinfI, HpaII, KpnI, RsaI, and TaqI. The RFLP patterns of 120 of the 250 samples matched patterns of the clover proliferation (CP) group (16SrVI) subgroup A (16SrVI-A) phytoplasma (1). In addition, the nested PCR product of P1A/P7A (2) following P1/P7 amplification was cloned and sequenced (GenBank Accession No. HQ609490). Nucleotide sequences were analyzed by iPhyClassifier software (4), confirming the relationship of this phytoplasma to ‘Candidatus Phytoplasma trifolii’ with RFLP patterns identical to group 16SrVI-A. To our knowledge, this is the first report of the CP group phytoplasmas associated with purple top diseased potatoes in China. References: (1) I.-M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998. (2) I.-M. Lee et al. Int. J. Syst. Evol. Microbiol 54:337, 2004. (3) C. D. Smart et al. Appl. Environ. Microbiol. 62:2988, 1996. (4) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.

scholarly journals First Report of Pomegranate Wilt Caused by Ceratocystis fimbriata in Yunnan, China

Plant Disease ◽  
2003 ◽  
Vol 87 (9) ◽  
pp. 1150-1150 ◽  
Author(s):  
Q. Huang ◽  
Y. Y. Zhu ◽  
H. R. Chen ◽  
Y. Y. Wang ◽  
Y. L. Liu ◽  
...  
Keyword(s):  
Yunnan Province ◽  
Disease Incidence ◽  
Punica Granatum ◽  
Ceratocystis Fimbriata ◽  
First Report ◽  
Initial Symptoms ◽  
Disease Surveys ◽  
Sterile Medium ◽  
Visible Symptom ◽  
Production Areas

Pomegranate (Punica granatum Linn.) is an important fruit crop in Yunnan Province, China. Recently, older pomegranate bushes in Mengzi County, Yunnan began dying. Initial symptoms were yellowing and wilting of leaves on one to several branches, followed by sudden death of the bush within 3 to 4 weeks. Roots of diseased bushes appeared brown to black, and irregularly shaped lesions were observed when the bark was removed. A species of Ceratocystis was consistently isolated from discolored roots, stem, and branch tissues from wilted bushes on potato dextrose agar (PDA) and was identified as Ceratocystis fimbriata Ellis & Halst, based on the morphology of perithecia, ascospores, conidia, and conidiophores. Perithecia were black with a globose base (130 to 300 μm) and a long neck (450 to 800 μm). Ascospores exuded from the apex of the perithecium neck in a long coil and were small, hyaline, and hat-shaped (3.8 to 5.0 μm long × 2.3 to 4.0 μm wide). Conidiophores were septate and hyaline to dark greenish brown. Hyaline conidia, 8 to 17 μm long × 6 to 15 μm wide, were usually produced in chains of 10 or more. Thick-walled endoconidia were globose to oval, olive brown, and 8 to 20 μm in diameter. Because of the increasing occurrence of the disease, surveys of the main pomegranate production areas in Mengzi County, including Xinan, Duofale, Caoba, Hongzhai, and Shilipu townships, were conducted from 10 to 20 August 2002. The disease was detected in 17 of 50 plantings surveyed. Disease was more severe in older plantings than in younger plantings. Disease incidence was 1% in 1- to 5-year-old bushes, 3.6% in 6- to 10-year-old bushes, and 6% in bushes more than 10 years old. Scolytid beetles were occasionally found on bushes, but we were unable to isolate the fungus from them as has been reported (1). Inoculations with an isolate of C. fimbrata were made by inserting mycelium with perithecia from 12-day-old cultures growing on PDA into root wounds made with a sterile scalpel on five pomegranate plants and then covering the wounds with Parafilm. Sterile medium was placed in an equal number of wounded bushes to serve as controls. Fourteen days later, symptoms began to appear in two bushes, and 5 days later, all bushes exhibited symptoms. No symptoms were observed on control bushes. The first visible symptom was a small area of blackened tissue near the point of inoculation. Lesions expanded slowly, but they expanded more rapidly upward than downward. The fungus was reisolated on PDA from roots of all artificially inoculated bushes. C. fimbriata has been previously reported as the cause of pomegranate wilt in India (2); however, to our knowledge, this is the first report of C. fimbriata on pomegranate in China. Because environmental conditions which favor the pathogen (temperatures ranging from 18 to 30°C and frequent rains) typically occur in many areas during late spring and summer, the disease has the potential to seriously impact pomegranate production in China. References: (1) Y. M. Somasekhara. Plant Dis. 83:400, 1999. (2) Y. M. Somasekhara, et al. Res. Crops 1(1):63, 2000.

scholarly journals Geospatial characterizing of Under-Five Mortality in Alexandria, Egypt

2021 ◽  
Author(s):  
Mahmoud Adel Hassan ◽  
Ahmed Mohamed Ramadan ◽  
Mohamed Mostafa Tahoun ◽  
Abdelrahman Omran ◽  
Shimaa Gad El-karim Ali ◽  
...  
Keyword(s):  
Cardiac Arrest ◽  
Spatial Distribution ◽  
Cardiovascular Diseases ◽  
Population Density ◽  
Spatial Pattern ◽  
Under Five ◽  
Size Population ◽  
Access To Water ◽  
Alexandria City ◽  
Low Incidence

This study aimed to identify geo-spatial pattern of under-five mortality (U5M) in Alexandria and its key determinants. We analyzed the geospatial distribution of 3064 deaths registered at 24 health offices reported from January 2018 to June 2019. The localities of Alexandria city were clustered into high and low incidence areas. Neonates represented 58.7% of U5M, while post-neonates and children were 31.1%, 10.2% respectively. Male deaths were significantly higher (P=0.036). The main leading causes of U5M were prematurity (28.32%), pneumonia (11.01%), cardiac arrest (10.57%), congenital malformation (9.95%), and childhood cardiovascular diseases (9.20%). Spatial distribution of U5M (including the most common three causes) tend to be clustered in western parts of Alexandria (El Hawaria, Bahig, Hamlis and Ketaa Maryiut). Another 9 clusters are at risk of being hotspots. Illiteracy, divorce, and poor locality characteristics (household size, population density, and access to water supply and sanitation), were statistically significant predictors of U5M.

scholarly journals Three decades of cotton disease surveys in NSW, Australia

2013 ◽  
Vol 64 (8) ◽  
pp. 774 ◽  
Author(s):  
K. A. Kirkby ◽  
P. A. Lonergan ◽  
S. J. Allen
Keyword(s):  
Bacterial Blight ◽  
Cultural Practices ◽  
Management Strategies ◽  
Cotton Production ◽  
South Wales ◽  
Resistant Varieties ◽  
Dramatic Decline ◽  
Disease Surveys ◽  
Production Areas ◽  
The Impact

Three decades of disease survey data have shown Verticillium wilt was one of the first major diseases of cotton recorded in the 1984–85 season. Survey reports the mean incidence was 4.1% in the 1984–85 season and rose to 16.6% in the 1989–90 season. Prior to 1984 all commercial varieties of cotton available in Australia were susceptible to bacterial blight and the disease was common. The adoption of the resistant varieties contributed to a dramatic decline in the incidence of bacterial blight and the removal of bacterial blight as a significant pathogen to Australian cotton crops by 1992. Survey results showed the incidence of black root rot increased on farms with a long history of growing cotton during the 1990s. Fusarium wilt of cotton was first reported in New South Wales (NSW) in 1994. The disease is now widespread, being confirmed on 86 NSW farms in six of the eight cotton production areas in NSW. These four significant plant disease ‘problems’ have challenged the cotton industry in NSW. Data provided by the surveys have indicated the relative importance of each of the diseases present and the impact of cultural practices and the adoption of new varieties on disease distribution, incidence and severity. The results have therefore been used to support and justify requests for research funding and have contributed to the development of Integrated Disease Management strategies. The NSW Department of Primary Industries continues to monitor the distribution of disease and the incidence and severity present in commercial cotton crops in all production areas of NSW. The aim of this paper is to highlight four significant cotton diseases in Australia and show relationships between cultural practices and declining and increasing incidence of disease.

Population structure of group B streptococcus from a low-incidence region for invasive neonatal disease

Microbiology ◽  
2005 ◽  
Vol 151 (6) ◽  
pp. 1875-1881 ◽  
Author(s):  
Naiel Bisharat ◽  
Nicola Jones ◽  
Dror Marchaim ◽  
Colin Block ◽  
Rosalind M. Harding ◽  
...  
Keyword(s):  
Population Structure ◽  
Disease Incidence ◽  
Group B Streptococcus ◽  
Invasive Disease ◽  
Multilocus Genotype ◽  
Neonatal Disease ◽  
Strain Collection ◽  
Low Incidence ◽  
Group B ◽  
Sequence Types

The population structure of group B streptococcus (GBS) from a low-incidence region for invasive neonatal disease (Israel) was investigated using multilocus genotype data. The strain collection consisted of isolates from maternal carriage (n=104) and invasive neonatal disease (n=50), resolving into 46 sequence types. The most prevalent sequence types were ST-1 (17·5 %), ST-19 (10·4 %), ST-17 (9·7 %), ST-22 (8·4 %) and ST-23 (6·5 %). Serotype III was the most common, accounting for 29·2 % of the isolates. None of the serotypes was significantly associated with invasive neonatal disease. burst analysis resolved the 46 sequence types into seven lineages (clonal complexes), from which only lineage ST-17, expressing serotype III only, was significantly associated with invasive neonatal disease. Lineage ST-22 expressed mainly serotype II, and was significantly associated with carriage. The distribution of the various sequence types and lineages, and the association of lineage ST-17 with invasive disease, are consistent with the results of analyses from a global GBS isolate collection. These findings could imply that the global variation in disease incidence is independent of the circulating GBS populations, and may be more affected by other risk factors for invasive GBS disease, or by different prevention strategies.

scholarly journals Effects of Initial Epidemic Conditions, Sporulation Rate, and Spore Dispersal Gradient on the Spatio-Temporal Dynamics of Plant Disease Epidemics

1998 ◽  
Vol 88 (10) ◽  
pp. 1000-1012 ◽  
Author(s):  
X.-M. Xu ◽  
M. S. Ridout
Keyword(s):  
Spatial Pattern ◽  
Power Law ◽  
Temporal Dynamics ◽  
Initial Conditions ◽  
Disease Incidence ◽  
Disease Status ◽  
Spatio Temporal ◽  
Disease Epidemics ◽  
Sporulation Rate ◽  
The Relationship

A stochastic model that simulates the spread of disease over space and time was developed to study the effects of initial epidemic conditions (number of initial inocula and their spatial pattern), sporulation rate, and spore dispersal gradient on the spatio-temporal dynamics of plant disease epidemics. The spatial spread of disease was simulated using a half-Cauchy distribution with median dispersal distance μ (units of distance). The rate of temporal increase in disease incidence (βI, per day) was influenced jointly by μ and by the sporulation rate λ (spores per lesion per day). The relationship between βI and μ was nonlinear: the increase in βI with increasing μ was greatest when μ was small (i.e., when the dispersal gradient was steep). The rate of temporal increase in disease severity of diseased plants (βS) was affected mainly by λ: βS increased directly with increasing λ. Intraclass correlation (κt), the correlation of disease status of plants within quadrats, increased initially with disease incidence, reached a peak, and then declined as disease incidence approached 1.0. This relationship was well described by a power-law model that is consistent with the binary form of the variance power law. The amplitude of the model relating κt to disease incidence was affected mainly by μ: κt decreased with increasing μ. The shape of the curve was affected mainly by initial conditions, especially the spatial pattern of the initial inocula. Generally, the relationship of spatial autocorrelation (ρt,k), the correlation of disease status of plants at various distances apart, to disease incidence and distance was well described by a four-parameter power-law model. ρt,k increased with disease incidence to a maximum and then declined at higher values of disease incidence, in agreement with a power-law relationship. The amplitude of ρt,k was determined mainly by initial conditions and by μ: ρt,k decreased with increasing μ and was lower for regular patterns of initial inocula. The shape of the ρt,k curve was affected mainly by initial conditions, especially the spatial pattern of the initial inocula. At any level of disease incidence, autocorrelation declined exponentially with spatial lag; the degree of this decline was determined mainly by μ: it was steeper with decreasing μ.

scholarly journals Emergence and epidemics of a new disease in araguaia valley: anthracnosis of cotton caused by Colletotrichum truncatum, varietal reaction and difficulties of chemical control

2020 ◽  
Vol 36 (6) ◽  
Author(s):  
Fernando Cezar Juliatti ◽  
Fernanda Cristina Juliatti ◽  
Breno Cezar Marinho Juliatti ◽  
Cristiane Aparecida de Paula
Keyword(s):  
Disease Incidence ◽  
Positive Interaction ◽  
Necrotrophic Pathogen ◽  
Prevalence Index ◽  
Resistance Response ◽  
Varietal Response ◽  
Detached Leaves ◽  
Low Efficiency ◽  
Production Areas

Cotton culture (Gossypium hirsutum L.) is trending in an upward expansion amidst Brazilian “cerrado”. Due this growth, new pathosystems are growing in incidence on tropical fields in the region of Araguaia Valley - MT. Surveys and material collection were conducted out in production areas on two counties (Bom Jesus - MT and Canarana – MT), both regions represents a total amount of 50.000 hectares of cultivated area. The region also is characterized by succession areas previously sowed with soybean plants (main cover crop season). Previously surveys revealed the incidence of target spot (Corynespora cassiicola), ramularia spot (Ramularia areola) and cercosporiosis (Cercospora gossypii). Disease incidence is commonly observed on several crop management methods and cultivars. Due to a reduction in efficacy of chemichal control by fungicides spray programs, this disease is increasing and spreading in a faster rate in production areas with previous harvested soybean at the biggest soybean producer group in the world (Bom Futuro). Plants on field were selected due to differences in symptoms, and isolation methods were carried out on PDA (potato-dextrose-agar) before “in vitro” pathogenicity tests conducted on seedlings, detached leaves and bolls (growth chamber conditions of 23°C / photoperiod of 12 hours). After Colletotrichum dextructor sp. pathogenicity confirmation, bioassays were carried out with several different fungicide’s groups (i.e. registered for usage on Brazilian jurisdiction). This test consisted of the employment of a solution with 500 ppm of each different fungicide/a.i. that is applied on infected bolls and detached leaves who were inoculated with the target pathogen (concentration of 104 conidia per mL). This test was followed by an infection (%) evaluation during 10 days of incubation. The incidence/prevalence index (%) was also evaluated at different parts of the plant (lower, middle, and upper canopy) on different cultivars/genotypes (130-150 days after sowing). A standard level of control by different fungicides, ranged between 0 to 100% of control. Two groups of cultivars/genotypes were separated after differences on resistance response, one with susceptible traits (FM 985 GLTP) and other with partial resistance traits. No immunity response was observed. We suggest that new efficacy tests should be carried out with combination of varietal response (resistance or tolerance) combined with other chemical fungicides for better understanding of synergism or positive interaction. Valuable information will highlight the best association for greater varietal response and yield against this necrotrophic pathogen (higher B0 – initial inoculum) survival during successive years of rotation main crop (cotton x soybean). Isolated spray of benzimidazoles, cupric (except cuprous oxide) and triple associations with triazoles or triazolinthione (prothioconazol) combined with strobilurins and carboxamides should be wisely administrated to manage this disease due to low efficiency (below 50%). New field and laboratory essay must be carried out to input data about resistance risk and clarify damage levels on leaves and bolls impacting yield.

scholarly journals Leaf and Stem Spot Caused by Ramularia sphaeroidea on Purple and Lana Woollypod Vetch (Vicia spp.) Cover Crops in California

Plant Disease ◽  
2004 ◽  
Vol 88 (2) ◽  
pp. 221-221 ◽  
Author(s):  
S. T. Koike ◽  
R. F. Smith ◽  
P. W. Crous ◽  
J. Z. Groenewald
Keyword(s):  
Cover Crops ◽  
Disease Incidence ◽  
Molecular Data ◽  
Tween 20 ◽  
Vegetable Production ◽  
Leaf Spots ◽  
Salinas Valley ◽  
Morphological And Molecular Data ◽  
Stem Lesions ◽  
Production Areas

Vetches (Vicia spp.) are planted alone or in combination with other plants as cover crops in vegetable production areas of California. December 2001 through February 2003, purple (V. benghalensis) and lana woollypod (V. villosa subsp. varia) vetches in the Salinas Valley (Monterey County) developed a foliar disease. Symptoms were small (≤5 mm in diameter), circular to oblong, purple brown-to-red brown spots that were visible from the adaxial and abaxial leaf sides, and occurred lower in the plant canopy. White sporulation was visible in the spot centers. Stems were infected and had elongated, irregularly shaped, brown lesions that were <5 mm long and had white sporulation. When fungal masses or tissues from lesions were placed on acidified potato dextrose agar (LA-PDA), a fungus was consistently recovered. On LA-PDA, the isolates produced slow-growing (30 mm colony diameter in 45 days), irregularly raised, light pink and white colonies that produced dark exudates. The undersurfaces of cultures were gray black. The growth on lesions consisted of fascicles of conidiophores that were hyaline, smooth, flexuous, distinctly geniculate, and measured 20 to 120 × 2.5 to 6 µm. Conidia were hyaline, subglobose, smooth, aseptate, measured 9 to 15 × 8 to 13 µm, and formed singly. The internal transcribed spacer rDNA sequence of a representative strain (CBS 112891) was determined using standard protocols (GenBank Accession No. AY352584). A nucleotide BLAST search revealed a 94 to 97% similarity to other species of Ramularia (GenBank Accession Nos. AF222848, AF173310, AJ417496, AF362060, and AF297235). On the basis of these morphological and molecular data, the fungus was identified as Ramularia sphaeroidea Sacc. (= Ovularia sphaeroidea (Sacc.) Sacc.) (1). Pathogenicity of six isolates grown on LA-PDA was confirmed by spraying conidial suspensions (1.0 × 105 conidia per ml) onto direct-seeded, 8-week-old, potted purple and lana woollypod vetch (12 plants each). Plants were kept in a dew chamber for 48 h and maintained in a greenhouse (23 to 25°C). After 7 to 10 days, all plants developed the characteristic leaf spots and stem lesions, and R. sphaeroidea was reisolated from such symptoms. Plants treated with only water did not develop symptoms. However, because disease incidence on test plants was low, inoculum was also prepared in water amended with 1.0 ppm of Tween 20. Four pots each of purple and lana woollypod vetch were sprayed with amended or nonamended inocula, and plants were handled as described. After 10 days, plants inoculated with Tween 20 amended inoculum had significantly higher disease incidence and severity (purple = 83% of leaflets infected with a mean of 3.4 spots per leaflet; lana = 83% infected with a mean of 3.2 spots) than did plants inoculated with water-only conidial suspensions (purple = 27% and a mean of 0.4 spots; lana = 38% and a mean of 0.6 spots). Finally, two other vetches used in the Salinas Valley were inoculated with the two suspensions. After 2 weeks, common (V. sativa) and languedoc (V. sativa ‘Languedoc’) vetch showed no symptoms, and control plants of purple and lana vetch developed disease. All inoculation tests were repeated, and results were similar. To our knowledge, this is the first report of R. sphaeroidea as a pathogen of purple and lana woollypod vetches in California. Reference: (1) U. Braun. A Monograph of Cercosporella, Ramularia, and Allied Genera (Phytopathogenic Hyphomycetes) Vol. 2. IHW-Verlag, Eching, Germany, 1998.

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