scholarly journals Development of Pre- and Postharvest Phytophthora Fruit Rot on Watermelons Treated with Fungicides in the Field

2014 ◽  
Vol 15 (3) ◽  
pp. 145-150 ◽  
Author(s):  
Chandrasekar S. Kousik ◽  
Jennifer L. Ikerd ◽  
Howard F. Harrison
Keyword(s):  
United States ◽  
Management Strategy ◽  
Phytophthora Capsici ◽  
Southeastern United States ◽  
Fruit Rot ◽  
Copper Hydroxide ◽  
The Past ◽  
Potassium Phosphite ◽  
Infested Field ◽  
Serious Disease

Fruit rot, caused by Phytophthora capsici, is a serious disease in most watermelon producing regions in the southeastern United States and has caused devastating losses over the past few years. Experiments were conducted from 2010 to 2013 in a P. capsici-infested field to identify fungicides effective for managing pre- and postharvest development of Phytophthora fruit rot. Weekly treatments of OXTP (Oxathiapiprolin), V-10208 (ethaboxam), Zampro (ametoctradin+dimethomorph), Forum (dimethomorph), Prophyt (potassium phosphite) + Kocide 2000 (copper hydroxide), Revus (mandipropamid) rotated with Prophyt + Kocide, and rotations of Revus with Presidio (fluopicolide) and Actigard with Revus significantly reduced preharvest fruit rot in the field compared to nontreated control. Symptomless fruit harvested four days after the last spray was inoculated with P. capsici and maintained in a humid chamber to evaluate postharvest fruit rot development. OXTP, Zampro, Forum, V-10208, Presidio rotated with Revus, and Actigard rotated with Revus applied in the field provided extended postharvest protection compared to nontreated control. Many of these fungicides belonging to different FRAC group should be used in rotations to manage Phytophthora fruit rot of watermelon and should be part of an overall management strategy that also includes use of well drained fields and proper irrigation practices. Accepted 25 August 2014. 29 September 2014.

scholarly journals Fungicide Rotation Programs for Managing Phytophthora Fruit Rot of Watermelon in Southeastern United States

2017 ◽  
Vol 18 (1) ◽  
pp. 28-34 ◽  
Author(s):  
Chandrasekar (Shaker) S. Kousik ◽  
Pingsheng Ji ◽  
Daniel S. Egel ◽  
Lina M. Quesada-Ocampo
Keyword(s):  
United States ◽  
South Carolina ◽  
Phytophthora Capsici ◽  
Southeastern United States ◽  
Heavy Rain ◽  
Integrated Approach ◽  
The United States ◽  
Fruit Rot ◽  
Management Options ◽  
Before And After

About 50% of the watermelons in the United States are produced in the southeastern states, where optimal conditions for development of Phytophthora fruit rot prevail. Phytophthora fruit rot significantly limits watermelon production by causing serious yield losses before and after fruit harvest. Efficacy of fungicide rotation programs and Melcast-scheduled sprays for managing Phytophthora fruit rot was determined by conducting experiments in Phytophthora capsici-infested fields at three locations in southeastern United States (North Carolina, South Carolina, and Georgia). The mini seedless cultivar Wonder and seeded cultivar Mickey Lee (pollenizer) were used. Five weekly applications of fungicides were made at all locations. Significant fruit rot (53 to 91%, mean 68%) was observed in the nontreated control plots in all three years (2013 to 2015) and across locations. All fungicide rotation programs significantly reduced Phytophthora fruit rot compared with nontreated controls. Overall, the rotation of Zampro alternated with Orondis was highly effective across three locations and two years. Rotations of Actigard followed by Ranman+Ridomil Gold, Presidio, V-10208, and Orondis, or rotation of Revus alternated with Presidio were similarly effective. Use of Melcast, a melon disease-forecasting tool, may occasionally enable savings of one spray application without significantly impacting control. Although many fungicides are available for use in rotations, under very heavy rain and pathogen pressure, the fungicides alone may not offer adequate protection; therefore, an integrated approach should be used with other management options including well-drained fields.

scholarly journals First Report of Insensitivity to Cyazofamid Among Isolates of Phytophthora capsici from the Southeastern United States

Plant Disease ◽  
2008 ◽  
Vol 92 (6) ◽  
pp. 979-979 ◽  
Author(s):  
C. S. Kousik ◽  
A. P. Keinath
Keyword(s):  
United States ◽  
South Carolina ◽  
Citrullus Lanatus ◽  
Phytophthora Capsici ◽  
Southeastern United States ◽  
Fruit Rot ◽  
Limiting Factor ◽  
Vegetable Production ◽  
Technical Grade ◽  
Lesion Diameter

Phytophthora capsici is rapidly becoming an important limiting factor in vegetable production in the southeastern United States, particularly on cucurbits as fruit rots. One of the strategies used to manage diseases caused by P. capsici is the regular application of fungicides. Recently the new fungicide cyazofamid (trade name Ranman, FRAC Group 21, FMC Corporation, EPA Reg. No. 71512-3-279) was registered for management of P. capsici on cucurbits. Cyazofamid has been reported to be very effective against P. capsici on peppers (1). In a recent evaluation, we observed that cyazofamid was not very effective on fruit rot of watermelon in a field artificially infested with P. capsici (3). Hence, we evaluated our collection of isolates for sensitivity to cyazofamid. We confirmed our isolates as P. capsici based on morphology of colonies and sporangia and amplification of internal transcribed spacer regions using specific PCR primers (4). Mycelial growth of 28 isolates from the southeastern United States including North (NC) and South Carolina (SC), Georgia (GA), and Florida (FL) was evaluated on Ranman amended (0, 25, 100, 310, 518, and 1,000 mg/liter of the active ingredient cyazofamid) V8 juice agar using similar techniques as described before (2). The EC50 (50% effective concentration) values ranged from 3.8 to 535 mg/liter. Thirteen isolates (8 GA, 3 SC, 1 NC, and 1 FL) had EC50 >100 mg/liter. Similar results were obtained when technical grade cyazofamid was used. The same 28 isolates were evaluated on media amended with technical grade cyazofamid (0, 1, 10, and 100 mg/liter) and 100 mg/liter of salicylhydroxaymic acid, which was added to inhibit the alternative oxidase enzyme. The EC50 values ranged from <1 to >100 mg/liter. Six isolates (5 GA and 1 NC) had EC50 >100 mg/liter. Three isolates, one sensitive and two insensitive, were used to inoculate cucumber (Cucumis sativus) fruits treated with commercial Ranman at 0, 10, 100, 300, and 1,000 mg/liter of cyazofamid plus the surfactant Silwett L-77 (0.52 ml/liter). Mycelial plugs (7-mm diameter) were placed on nonwounded fruits. Fruits were kept under high humidity at 25 ± 1°C in an incubator for 3 days. Two measurements of each lesion at right angles were averaged to get the lesion diameter. The EC50 value for lesion diameter on fruits varied from 13 mg/liter for the sensitive isolate to >233 mg/liter for the insensitive isolates. EC50 values for diameter of the lesion with sporulation ranged from 3 to 107 mg/liter. Relative lesion diameters of the insensitive isolates at 100 mg/liter treatment compared with nonsprayed check were 70 to 93%, and at 300 mg/liter, it was 38 to 80%. Similarly in another experiment, watermelon (Citrullus lanatus var. lanatus) fruits were sprayed with a recommended field rate of Ranman (284 mg of cyazofamid/liter) plus Silwett L-77 (0.52 ml/liter) till runoff and inoculated with four isolates. The relative lesion diameter for insensitive isolates on Ranman treated watermelon fruits were 76 to 100% of nonsprayed fruits. To our knowledge, these insensitive isolates were collected from fields that were never sprayed with Ranman. Because of the existence of cyazofamid insensitive P. capsici isolates, it should be rotated with fungicides from other chemical classes to prevent extensive selection of insensitive isolates. References: (1) K. L. Ivors et al. Plant Dis. Manage. Rep. 1:V088, 2007. (2) A. P. Keinath. Plant Dis. 91:743, 2007. (3) C. S. Kousik and R. Hassell. Plant Dis. Manage. Rep. 1:V010, 2007. (4) J. B. Ristaino et al. Appl. Environ. Microbiol. 64:948, 1998.

Archaic Shell Mounds in the American Southeast

2017 ◽  
Author(s):  
Rebecca Saunders
Keyword(s):  
United States ◽  
Southeastern United States ◽  
Savannah River ◽  
The Past ◽  
Island Area ◽  
Recent Scholarship ◽  
Shell Mounds ◽  
The Future ◽  
American Southeast ◽  
Shell Rings

Freshwater and estuarine shellfish began to be exploited in the southeastern United States between 9000 and 7000 b.p. Shortly thereafter, shell mounds appeared in the mid-South Shell Mound Archaic, along the St. Johns River in peninsular Florida, and, somewhat later, in the Stallings Island area along the middle Savannah River. On the lower Atlantic and Gulf Coasts, shell rings arose. Until recently, all these mounds were considered middens—the accumulations of the remains of simple meals of mobile peoples who visited the same areas for hundreds or thousands of years. More recent scholarship indicates that these mounds were deliberate constructions—some of the first sculpted landscapes created by Archaic peoples to memorialize the past, celebrate the present, and provide for the future. In this chapter, recent research on shell sites in these four areas is discussed. The emphasis is on changing perspectives about the peoples who built them.

Muskogean Languages

2017 ◽  
Author(s):  
Jack B. Martin
Keyword(s):  
United States ◽  
Word Order ◽  
Southeastern United States ◽  
Noun Phrases ◽  
Verbal Aspect ◽  
The Past ◽  
The Family

The Muskogean languages are a family of languages indigenous to the southeastern United States. Members of the family include Chickasaw, Choctaw, Alabama, Koasati, Apalachee, Hitchiti-Mikasuki, and Muskogee (Creek). The trade language Mobilian Jargon is based on Muskogean vocabulary and grammar. The Muskogean languages all have SOV word order. Noun phrases are marked for subject or non-subject case. Alienable and inalienable possession is marked on possessed nouns. Agreement on verbs for subjects and objects is sensitive to agency. The languages have grammatical tone (used to indicate verbal aspect) and switch reference. Several of the languages have measured tense systems (indicating several degrees of distance in the past).

scholarly journals Tomato Transplant Age: A Review

1993 ◽  
Vol 3 (3) ◽  
pp. 313-316 ◽  
Author(s):  
Charles S. Vavrina ◽  
Michael D. Orzolek
Keyword(s):  
United States ◽  
Lycopersicon Esculentum ◽  
Southeastern United States ◽  
Commercial Production ◽  
The Past ◽  
The Many ◽  
University Scientists ◽  
The Ideal

As early as 1929, university scientists began the quest to determine the ideal age at which to transplant tomatoes (Lycopersicon esculentum Mill.). Investigations have included seedlings of 2 to 15 weeks of age produced in wood, peat, plastic, or Styrofoam containers. Early researchers often omitted descriptions of soil mixes and nutrient regimes, and used a wide variety of container types. Later investigators were inclined to use commercial soilless mixes, well-defined nutrient regimes, and polystyrene trays. Pioneers of transplant age research tended to use plants of 7 weeks and older, whereas work within the past 30 years has concentrated on younger plants. Many researchers drew conclusions after only 1 year of experimentation, while others found that results varied across years. Prior to the 1980s, virtually all studies were initiated and conducted in areas far from the thriving transplant industry established in the southeastern United States. Southern-grown transplants often were not in cluded for comparison, and few studies were implemented using plants grown under commercial conditions. After more than 60 years of transplant age research, it appears that transplants of 2 to 13 weeks can produce comparable yields, depending on the many factors involved in commercial production.

Influence of the "Hypsithermal Age" and "Neoglaciation" climatic conditions on the Brazilian coast.

2001 ◽  
Vol 28 (2) ◽  
pp. 213 ◽  
Author(s):  
KENITIRO SUGUIO
Keyword(s):  
United States ◽  
Gulf Of Mexico ◽  
Sea Level ◽  
Southeastern United States ◽  
Climatic Conditions ◽  
Brazilian Coast ◽  
Sea Level Changes ◽  
Relative Sea Level ◽  
Sea Levels ◽  
The Past

Meanwhile the highest relative sea-level is the present one in southeastern United States (Gulf of Mexico) or in Netherlands coast, most of the Brazilian coast exhibited Holocene sea-levels higher than the present in the past. The Brazilian curves, representing the relative sea-level changes during last 7.000 years, are outlined using sedimentological, biological and prehistorical past sea-level records. This paper shows that these relative sea-level records, during the Holocene, can be suitably used to demonstrate the influence of the worldwide known paleoclimatic events, like the “Hypsithermal Age” and “Neoglaciation” on the Brazilian coast.

scholarly journals Characterization of Colletotrichum Species Causing Anthracnose of Pomegranate in the Southeastern United States

Plant Disease ◽  
2019 ◽  
Vol 103 (11) ◽  
pp. 2771-2780 ◽  
Author(s):  
Katia V. Xavier ◽  
Achala N. KC ◽  
Natalia A. Peres ◽  
Zhanao Deng ◽  
William Castle ◽  
...  
Keyword(s):  
United States ◽  
Species Complex ◽  
Southeastern United States ◽  
Leaf Blight ◽  
Fruit Rot ◽  
Internal Transcribed Spacer Region ◽  
Colletotrichum Species ◽  
Species Complexes ◽  
Commercially Important ◽  
Pomegranate Fruit

Anthracnose fruit rot and leaf blight caused by Colletotrichum species are important diseases of pomegranate in the southeastern United States. In this study, 26 isolates from pomegranate were identified based on pathological and molecular characterization. Isolates were identified to species based on multilocus sequence analysis with the internal transcribed spacer region, glyceraldehyde-3-phosphate dehydrogenase, β-tubulin, and chitin synthase genomic genes. Pomegranate isolates grouped within the C. acutatum and C. gloeosporioides species complexes, with more than 73% belonging to the latter group. Three species were identified within the C. acutatum species complex (C. nymphaeae [n = 5], C. fioriniae [n = 1], and C. simmondsii [n = 1]), and three other species were identified within the C. gloeosporioides species complex (C. theobromicola [n = 11], C. siamense [n = 6], and C. gloeosporioides [n = 2]). Inoculations of pomegranate fruit showed that isolates from the C. acutatum species complex were more aggressive than isolates from the C. gloeosporioides species complex. Interestingly, opposite results were observed when leaves of rooted pomegranate cuttings were inoculated. In addition, Colletotrichum isolates from pomegranate, strawberry, blueberry, mango, and citrus were cross-pathogenic when inoculated to fruit. This is the first study identifying six different species of Colletotrichum causing pomegranate leaf blight and fruit anthracnose in the southeastern United States and the potential cross-pathogenic capability of pomegranate isolates to other commercially important crops.

Controlling Florida Betony (Stachys floridana) with Herbicides

2010 ◽  
Vol 24 (1) ◽  
pp. 25-27
Author(s):  
Mark A. Czarnota
Keyword(s):  
United States ◽  
Combination Treatment ◽  
Southeastern United States ◽  
Good Control ◽  
Sulfonylurea Herbicides ◽  
The Past ◽  
Selective Control ◽  
Picolinic Acids

In the southeastern United States, Florida betony continues to be a problem weed in both turfgrass and ornamentals. Several herbicides including atrazine, dichlobenil, and glyphosate can provide good control (greater than 70%) of Florida betony, but their uses are limited. Over the past several years, many additional herbicides have been added to the turf market. New herbicides evaluated in this study included the sulfonylurea herbicides foramsulfuron, metsulfuron, and trifloxysulfuron; the picolinic acids clopyralid and fluroxypyr; and the aryl triazinone herbicide carfentrazone in combination with 2,4-D, dicamba, and mecoprop. In both the 2004 and 2005 trials, all sulfonylurea herbicides provided greater than 83% control of Florida betony at 10 wk after treatment. Other herbicides that provided less than 80% control of Florida betony in 2004 and 2005 included clopyralid, fluroxypyr, and the carfentrazone combination treatment. Selective control of Florida betony in ornamentals, however, still remains a challenge, as none of these herbicides are labeled for ornamentals.

Differences in Susceptibility to Phomopsis Blight of Seven Eggplant Cultivars with Different Fruit Types

2021 ◽  
Author(s):  
Anthony Keinath
Keyword(s):  
Fairy Tale ◽  
Disease Incidence ◽  
Southeastern United States ◽  
Late Summer ◽  
Fruit Rot ◽  
Stem Length ◽  
Moderate Number ◽  
Marketable Fruit ◽  
Serious Disease ◽  
Black Beauty

Phomopsis blight caused by Diaporthe vexans is a serious disease on fall eggplant crops in the southeastern United States. The objective was to compare seven eggplant cultivars, representing seven horticultural fruit types, for susceptibility to D. vexans. Eggplant transplanted in April 2018 and 2019 was cut back in late summer and harvested in September and October. Leaf disease incidence was lower on Rosa Bianca (Italian type) and Gretel (white) both years than on other cultivars, except Millionaire (Japanese) in 2018 (P ≤ 0.01). Leaf AUDPC based on severity and percentage defoliation were greater on Black Beauty (globe type) than Patio Baby (Indian), Millionaire (Japanese), Rosa Bianca (Italian), and Gretel (white). Cankered stem length was greater on Black Beauty and Fairy Tale than on Gretel. Hansel (Chinese) and Gretel produced the most healthy, unblemished marketable fruit; Patio Baby, Millionaire, and Fairy Tale had a moderate number; and Black Beauty and Rosa Bianca produced the fewest fruit. Percentage fruit rot both years was greater (P ≤ 0.01) on Black Beauty than Hansel, Gretel, Patio Baby, and Rosa Bianca. Several eggplant cultivars, such as Hansel and Gretel, are less susceptible to Phomopsis fruit rot than Black Beauty and produce more marketable fruit than several other specialty eggplant cultivars.

scholarly journals A Detached Cucumber Fruit Method to Screen for Resistance to Phytophthora capsici and Effect of Fruit Age on Susceptibility to Infection

Plant Disease ◽  
2006 ◽  
Vol 90 (10) ◽  
pp. 1276-1282 ◽  
Author(s):  
A. J. Gevens ◽  
K. Ando ◽  
K. H. Lamour ◽  
R. Grumet ◽  
M. K. Hausbeck
Keyword(s):  
Management Strategy ◽  
Phytophthora Capsici ◽  
Fruit Rot ◽  
Michigan State University ◽  
State University ◽  
Plant Introductions ◽  
Susceptibility To Infection ◽  
Cucumber Fruit ◽  
History Of ◽  
Standard Practices

Identification and utilization of resistance to Phytophthora capsici could provide the basis for a viable management strategy against cucumber fruit rot, a persistent threat in cucumber (Cucumis sativus) production. Our objectives were to develop a method for testing detached, nonwounded, cucumber fruit for resistance to P. capsici, and to screen cucumber cultivars and plant introductions (collectively referred to as cultigens) for resistance. Four P. capsici isolates (differing in their sensitivity to the fungicide mefenoxam and compatibility type) were compared for their fruit infection capability in 1999 and 2000. No significant differences were found among isolates, and a single isolate was used for all subsequent screens. From 1999 to 2004, 480 cucumber cultigens were grown according to standard practices at Michigan State University research farms in four fields with no history of P. capsici. Commercially mature fruit were harvested, inoculated with P. capsici, and rated for lesion diameter, pathogen sporulation diameter, and density of pathogen sporulation. Although no fruit exhibited complete resistance to P. capsici, some cultigens exhibited limited pathogen sporulation. In the process of screening, it was observed that younger, smaller fruit were comparatively more susceptible than older, larger fruit. Replicated trials with hand-pollinated fruit showed that the transition from susceptible to more resistant appeared to coincide with the transition from the period of rapid fruit elongation to the period of increased fruit diameter. This is the first report using a nonwounded fruit screen to analyze cucumber resistance to P. capsici.

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