Causal Agent: 

Tobamovirus (Tobacco mosaic virus or TMV; Tomato mosaic virus or ToMV)

Characteristic Symptoms:
 
Affects all growth stages of the plant.
   
Symptoms include mosaic on leaves with distortion of younger leaves and narrowing of leaf tips, necrosis and distortion of severely affected leaves, defoliation and stunting.
   
Occasionally, wilting of stems and leaves and necrosis on fruits.
   
Transmission and Spread:
 
Both viruses are seed-borne and easily transmitted by contact or through contaminated hands, clothing, farm tools and implements.
   
Other sources of the virus are infected weed species, irrigation water, tobacco products used for smoking and TMV-infected tobacco plants.
   
The virus is quite stable under adverse environmental conditions and can persist in plant debris in dry soil for 2 years or in moist soil for 1 month or in root debris in fallow soil for 22 months.
   
The virus can also persist in greenhouse structures for long periods of time.
   
Management and Control:
 
Use resistant varieties, if available.
   
Use virus-free seeds and seedlings.
   
Carefully remove and destroy infected plants as early as virus symptoms are observed to prevent/minimize spread of the virus by direct contact between plants.
   
Remove weeds that may serve as hosts for the virus.
   
Avoid touching the plants or dip hands in skim milk while handling plants every 5 minutes.
   
Disinfect stakes, tools and implements by soaking in 10% household bleach (chlorox) for 10 minutes or in 3% TSP for 30 minutes.
   
Work in unaffected areas first before working in diseased areas.
   

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