1. World problems
  2. Viral plant diseases

Viral plant diseases

  • Virus diseases in plants

Nature

A number of infectious plant diseases result from viruses. Major crops that are seriously affected by virus diseases include: tobacco, potato, sugar beet and cane, peach, orange, cotton and wheat. Most of the plant viruses impair or destroy chlorophyll, causing the plant to wilt or die; some viruses, though, stunt or otherwise deform plants without seriously affecting the chlorophyll.

Background

The importance of virus diseases on crop plants has increased tremendously in the past 50 years. Since 1900, more than 200 new plant viruses have been discovered. Many of them have done widespread damage to crop plants. Curly top caused almost complete abandonment of the sugar beet industry in parts of western USA from 1926 to 1932 and still causes severe injury to tomatoes, beans and a number of other crops. Sugarcane mosaic caused extensive losses to the sugarcane industry in the USA, Argentina, Brazil, and other countries beginning about 1917. Spotted wilt has become widespread and now causes losses to tomato and other crops in many parts of the world. Since 1940, swollen shoot has caused extensive damage to the cacao industry of west Africa. Virus diseases of citrus trees have become more destructive and from 1936 to 1946 tristeza caused the loss of 7 million orange trees in the state of Sao Paulo, Brazil, alone. It has attacked or now threatens millions of trees in various tropical and subtropical areas. This increase in destructiveness of virus diseases and in the number of known viruses has come about largely as a result of the expansion of agricultural enterprises and the increased movement of plants and plant products in recent years.

Incidence

Virus diseases of plants are widespread, and many of them cause economic loss. The whole organization of the potato industry is conditioned by the necessity for minimizing virus diseases. For more than a century it has been known that if a farmer in the UK continued to use his own seed potatoes for successive crops, degeneration progressed gradually until the great majority of the plants were malformed and stunted. Among other important crop diseases caused by viruses are spotted wilt of tomato, tobacco mosaic, leaf curl of cotton in the Sudan, and swollen shoot disease of cacao. The tobacco mosaic virus besides affecting many members of the nightshade family (Solanaceae), which includes tobacco, tomato and potato, occurs on some 30 species of plants in 14 other families.

Viruses originate in local areas all over the world. Through long association native plants have developed a tolerance to the local viruses that enables infected individuals to survive with little injury. When crop plants are introduced into an area they frequently become subject to infection with the native viruses, against which they have had no opportunity to develop resistance. Such a virus may cause extensive losses to a crop plant, not only in the areas of original distribution of the virus, but also in the other areas to which it may spread on the recently attacked crop plant. Virus diseases produce a wide range of symptoms and types of injury on plants. Sometimes they kill the plant in a short time, as with spotted wilt and curly top on tomato. More often they cause lesser injuries that result in reduced yields and lower quality of product. With respect to the general symptoms produced, most viruses are of two rather clearly defined groups: those that cause mottling or spotting of leaves, and those that cause a yellowing leaf, curling, dwarfing, or excessive branching, but little or no mottling or spotting.

Claim

Viral plant diseases pose a critical threat to global agriculture and food security. These pathogens can devastate crops, leading to significant economic losses and jeopardizing livelihoods. As climate change accelerates, the spread of these viruses is becoming more rampant, affecting not only farmers but also consumers worldwide. Urgent action is needed to enhance research, develop resistant varieties, and implement effective management strategies. Ignoring this issue could result in catastrophic consequences for our food systems and biodiversity.This information has been generated by artificial intelligence.

Counter-claim

Viral plant diseases are often overstated as a significant problem. While they can affect crop yields, the agricultural industry has robust methods for management and control. Advances in biotechnology and breeding techniques continually enhance plant resilience. Moreover, the focus on viral diseases distracts from more pressing issues like climate change and sustainable farming practices. In the grand scheme, the impact of viral plant diseases pales in comparison to the broader challenges facing global agriculture today.This information has been generated by artificial intelligence.

Broader

Viral diseases
Presentable
Plant pathogens
Unpresentable

Narrower

Tobacco mosaic
Yet to rate
Plum pox virus
Yet to rate
Oryzavirus
Yet to rate
Fijivirus
Yet to rate
Aster yellows
Yet to rate

Aggravates

Aggravated by

Aphids as pests
Presentable

Related

Parasites on plants
Unpresentable

Strategy

Value

Disease
Yet to rate

Reference

Metadata

Database
World problems
Type
(D) Detailed problems
Biological classification
N/A
Subject
  • Biosciences » Bacteriology
  • Medicine » Pathology
  • Plant life » Plants
  • Content quality
    Excellent
     Excellent
    Language
    English
    1A4N
    D2227
    DOCID
    11422270
    D7NID
    135336
    Last update
    Mar 10, 2022