Pest Of The Month: Tomato Chlorosis Virus

Pest Of The Month: Tomato Chlorosis Virus

Identification

Tomato chlorosis virus (ToCV) is a relatively new disease in Florida that is being seen with increasing frequency in some areas. Detection can be difficult since the symptoms overlap abiotic symptoms of nutrient deficiency or herbicide phytotoxicity.

The leaves of plants infected with ToCV become yellow or purplish between the veins, stunted, and rolled. Onset of disease appears to occur during the short day-length period of late December through February. Symptoms are typically most apparent on middle to lower parts of plants, while new growth may appear normal. Lower leaves develop a progressive, interveinal chlorosis, often with necrotic flecking.

Symptoms resemble those caused by magnesium deficiency in tomato, but are less uniform within a leaflet or among leaflets on a leaf. As the disease progresses, interveinal necrosis can occur and the leaves become characteristically brittle, thick, and crisp. Fruit size and number appear reduced by virus infection.

Survival And Spread

ToCV is transmitted by whiteflies, including the banded wing whitefly (Trialeurodes abutilonea), greenhouse whitefly (T. vaporariorum), silverleaf whitefly (Bemisia tabaci biotype B), and sweetpotato whitefly (B. tabaci biotype A). The most efficient vector of ToCV is the silverleaf whitefly, which is present in Florida in abundance.

Transmission of ToCV is relatively efficient; whiteflies can transmit the virus with feeding times as short as an hour, but become more efficient the longer they are allowed to feed. The good news is that unlike tomato yellow leaf curl virus (TYLCV), in which case the virus can be transmitted for the length of the whitefly’s life (several weeks), ToCV can only be transmitted by a viruliferous whitefly for one to nine days.

Management
As with TYLCV, control of the virus vectors is an important strategy in ToCV management. The major way to reduce losses from criniviruses in tomato is insecticide-based control. Neonicitinoid-based products are most frequently used for whitefly control, and can be applied as a foliar spray, a seed treatment, or through drip application. While insecticides effectively reduce whitefly populations, such control methods are relatively inefficient for control of viruses, since whiteflies can transmit a virus before being killed by an insecticide. Unfortunately, most whitefly-transmitted criniviruses do not produce symptoms until three to four weeks after infection occurs. Therefore, infection can be widespread by the time symptoms are observed and control measures are implemented.

Growers can minimize exposure to ToCV by avoiding overlap with other susceptible crops. Avoid using infected transplants. Roguing of infected plants and general whitefly control may also help reduce virus spread.

Leave a Reply

Disease Control Stories
Crop ProtectionLettuce Disease Gives E. Coli A Boost
July 31, 2015
E. coli prefer cut, injured, and young lettuce leaves. Read More
Crop ProtectionNew Fungicide Targets Key Diseases
July 30, 2015
This disease control tool hits two different parts of the fungal life cycle. Read More
Disease ControlNew Disease Control Tools For Fruit And Nut Growers
July 29, 2015
Apple scab is a big problem for growers in the Midwest and East. But, a new fungicide boasts efficacy against Read More
Late blight shown in a tomato
Disease ControlLate Blight Identified In Indiana, Michigan
July 28, 2015
A potato field in Michigan and a potato and tomato field in Indiana have documented the disease. Read More
downy mildew symptoms on basil
Disease ControlRed Lights Slow Down Growth Of Downy Mildew On Basil
July 22, 2015
University of Florida scientists say the technology may help growers manage the disease and reduce chemical inputs. Read More
Bacterial wilt of curcurbits
CucurbitsWin The War Against Bacterial Wilt Of Cucurbits
July 22, 2015
Learn how to identify, the survival and spread, as well as management methods of this vegetable disease. Read More
Disease ControlStone Fruit Rots Rampant In East
July 21, 2015
The incidents of fruit rots in both sweet and tart cherries and peaches and nectarines are quite high in Pennsylvania Read More
The Latest
Disease ControlBioSafe Systems’ ZeroTol 2.0 Now OMRI Certified
August 25, 2015
Broad spectrum bactericide/fungicide is now cleared for use in organic production. Read More
Disease ControlProtect Hail-Damaged Grape Clusters From Botrytis
August 11, 2015
Recent hailstorms hit Northwest Michigan hard. Grapes, tart cherries, and apples orchards were hit by high winds and nickel- to Read More
Disease ControlCopper Injury And Bacterial Spot Are Easily Confused
August 4, 2015
In her latest bulletin for tree fruit growers, Kari Peter of Penn State University Extension says it is easy to confuse the Read More
Crop ProtectionLettuce Disease Gives E. Coli A Boost
July 31, 2015
E. coli prefer cut, injured, and young lettuce leaves. Read More
Crop ProtectionNew Fungicide Targets Key Diseases
July 30, 2015
This disease control tool hits two different parts of the fungal life cycle. Read More
Disease ControlNew Disease Control Tools For Fruit And Nut Growers
July 29, 2015
Apple scab is a big problem for growers in the Midwest and East. But, a new fungicide boasts efficacy against Read More
Late blight shown in a tomato
Disease ControlLate Blight Identified In Indiana, Michigan
July 28, 2015
A potato field in Michigan and a potato and tomato field in Indiana have documented the disease. Read More
downy mildew symptoms on basil
Disease ControlRed Lights Slow Down Growth Of Downy Mildew On Basil
July 22, 2015
University of Florida scientists say the technology may help growers manage the disease and reduce chemical inputs. Read More
Bacterial wilt of curcurbits
CucurbitsWin The War Against Bacterial Wilt Of Cucurbits
July 22, 2015
Learn how to identify, the survival and spread, as well as management methods of this vegetable disease. Read More
Disease ControlStone Fruit Rots Rampant In East
July 21, 2015
The incidents of fruit rots in both sweet and tart cherries and peaches and nectarines are quite high in Pennsylvania Read More
UF/IFAS scientists Edward Evans and Jonathan Crane study diseased avocados in a South Florida grove.
Disease ControlDeadly Disease Cutting Down Florida Avocado Trees Likel…
July 17, 2015
The economic impacts of laurel wilt disease management costly for domestic producers. Read More
tomato plants showing signs of Fusarium wilt
Disease ControlGrowers, Scientists Setting Sights On Soilborne Disease
July 14, 2015
Further removed from methyl bromide, nasty maladies like Fusarium are finding a way back into fields. Read More
Crop ProtectionEarly Blight And Septoria Leaf Spot Rampant On Pennsylv…
July 8, 2015
According to a news release from Penn State University, early blight and Septoria leaf spot are present in Pennsylvania tomato Read More
Crop ProtectionDowny Mildew Reported In Ohio Cucumber Fields
July 8, 2015
According to a disease update from Ohio State University Extension, downy mildew was reported in cucumbers on farms in West Read More
BerriesRainy Weather Causing High Risk For Phytopthora In Berr…
June 29, 2015
With the rainy weather the Midwest has recently received, the conditions for Phytophthora diseases increases. An increased risk for oomycetes, Read More
Disease ControlQuintec Fungicide Receives Label For Bacterial Spot Sup…
June 26, 2015
Quintec fungicide from Dow AgroSciences, known as an effective treatment for suppressing bacterial spot in peppers, is now available to Read More
Crop ProtectionDowny Mildew Makes Early Appearance In Michigan Cucumbe…
June 23, 2015
An alert sent by Michigan State University (MSU) Extension confirms the presence of downy mildew on cucumber leaves in Michigan. Read More
Apples & PearsDon’t Neglect Overwintering Fire Blight Cankers
June 22, 2015
Canker blight has been seen in Pennsylvania orchards, thanks to ideal weather conditions as of late. Kari Peter of Penn Read More