Plant disease resistance protects plants against pathogens in two ways: through effective structures and chemicals and through the induced response of the immune system. Disease resistance is the reduction of pathogens that grow on the plant. he develops plants with few diseases in terms of pathogens. The three-way interaction of pathogens is used to determine disease outcome, environmental conditions and the plant. Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get the original essay The defense activating compound can move from cell to cell and through the plant vascular system. Infecting the plant has no circulating immune cells. Different cell types possessing broad antimicrobial defense. There are approximately 450 species of plant pathogenic viruses that limit disease. Plants have adapted detailed action and defense mechanisms to prevent or limit viral infection. RNA silencing has made considerable progress and is an important avenue. These steps provide effective protection against plant viruses. Plants have evolved various approaches to virus resistance, while different viruses have overcome these resistance barriers. Resistance to plant viruses presents different levels and different mechanisms. Different isolated genes are involved in resistance. To obtain a virus-resistant host plant, the scope of operational strategy is used today. infect for centuries, plant breeders are able to invent natural genes into suitable genotypes without knowing the resistance traits they knew by growing mainly dominant resistance genes, and analyzed, I not only described the natural plant defense system, but I also gave a suitable way to use a gene far from the species boundary. In addition to using natural traits, we also used certain types of virus resistance that have been established over the last fifteen years. The very first success achieved using the pathogen principle explored resistance by transferring the host plant with viral genes and/or with sequences intended to block a specific step. plants are involved in a rich environment and eager to exploit the biosynthesis and energy production capacity of plants. The concept of viruses was discovered with the tobacco mosaic virus in the late 19th century. In this section, I have highlighted these findings. We must divide plant virus research according to the “classical discovery period” from 1883 to 1951, during which research was very descriptive; an "early molecular era" from approximately 1952 to 1983, during which informative knowledge describing other premises of viruses developed, aided by the expansion of a number of important know-how, and " recent eras” from 1983 to the present, where techniques have been developed to modify the genome type of plant viruses, to detect nonstructural gene products, to identify the functionality of viral gene products, and to transmute plants to bring out the original formation of resistance to viral diseases. At this time, plant virology played a notable role in developing an understanding of the mechanisms of gene inactivation and recombination, plasmodesmatous function, systemic acquired resistance, and in the evolution of bacterial diagnostic methodology. .We also endeavor to speculate on the regulation of plant virology in the coming years. Mosaic virus infects plants in several ways. This virus infects more than 150 types of plants, including many vegetables, fruits and flowers. It is characterized by leaves mottled with white, yellow and dark and light green spots or stripes. Some of the most commonly infected plants include tomatoes, squash, cauliflower and cucumbers. Cucumber mosaic virus is one of the more unusual types of mosaic virus, and it is usually spread by aphids. As can be inferred from its name, cucumber mosaic virus, frequently affects cucumbers, but it is also a common problem for melons, tomatoes, squash, and some other plants. Tobacco mosaic virus is spread by seed and direct contact, and the best way to avoid it is to grow resistant varieties. Viral diseases are difficult to identify because the brand or indication is different from plant to plant and may also differ depending on age. limit of the plant and its growing conditions. However, the most common ways to recognize mosaic viruses are given below. The leaves are spotted with white. yellow and dark green and light green spots, which appear raised. These give the leaves a blister-like appearance. Plants are often stunted or grow very poorly. Plants may have other deformed parts and their leaves may be wrinkled or wavy. Cucumber mosaic virus; Infected plants are stunted and frequently exhibit "drawstring syndrome", which is a characteristic abnormality in which leaf margins fail to develop, with leaf veins developing as long, restricted strips. The tomatoes are small and misshapen. Tobacco mosaic virus; Infected plants have distorted, yellowed leaves and young shoots that are twisted, wrinkled, or misshapen. Once plants are affected, there is no control. Remove all infected and damaged plants. Also be sure to sterilize your gardening gadgets. Plant hardy plants when they are available in your garden. Tomato varieties resistant to cucumber mosaic virus have not yet been discovered, but tomatoes resistant to tobacco mosaic virus may also have modest resistance to cucumber mosaic virus. Mosaic viruses are usually spread by insects, including aphids and leafhoppers. You can try covering your plants with a floating row cover or aluminum foil mulch to prevent these insects from infecting your plants. Check out our other tips for fighting aphids. Control your weeds. Some types can serve as diseases for the host. To prevent tobacco mosaic virus, soak seeds in a 10% bleach solution before planting and avoid grabbing tobacco near plants. The plants most affected are tomatoes, cucumbers, cauliflower and squash (zucchini). Tobacco mosaic virus (TMV) infects commercially grown tobacco (Nicotiana tabacum L.) worldwide, reducing yield and quality. The RNA plant virus spreads mechanically and causes a mottled pattern of light and dark green areas to develop on infected leaves. Good sanitation and good cultural practices are the best ways to prevent disease. Resistance is the best way to combat TMV once the disease infectsa culture. The N gene is the most widely used TMV resistance gene. The N gene was transferred into N. tabacum from N. glutinosa. Once a plant containing the N gene is inoculated with TMV, a hypersensitivity reaction occurs at the virus entry points. The interaction of the N gene product with the TMV virus causes the plant to kill its own cells at any time the virus enters. Subsequently, lesions form on any inoculated leaves, restricting the movement of the virus to other parts of the plant and, more importantly, to other plants. The N gene is effective in Burley tobacco and keeps the incidence of TMV very low. The N gene has also been transferred to flue-cured tobacco, but plants containing the gene generally have lower yield and quality. There may be negative binding factors associated with the N gene that are very difficult to break in flue-cured tobacco. The N gene was incorporated into flue-cured tobacco in the homozygous state as well as in the heterozygous state. Cultivars deriving resistance from the N gene in the heterozygous state also have reduced yield and quality, but the effect is not as great as in plants containing the N gene in the homozygous state. Plant breeders began developing more tobacco hybrids incorporating the N gene in a heterozygous state so that TMV could still be controlled, but with fewer deleterious agronomic effects. The N gene in the heterozygous state could be the solution for farmers who must plant tobacco in fields where TMV incidence is known to be high. The N gene induces a very reliable and satisfactory defense mechanism against TMV; however, the disadvantages of using the N gene have not been completely overcome. Identification of TMV resistance in N. tabacum germplasm may be less likely to exhibit negative linkage traits associated with resistance. Chaplin and Gooding (1969) examined tobacco introductions using N. tabacum germplasm and found some accessions that induced a hypersensitive response when inoculated with TMV. The N gene may be responsible for controlling the resistance found in these tobacco introductions, or an entirely different source of resistance may be responsible. Significance In 1898, Martinus W. Beijerinck of the Netherlands put forward his idea that TMV was small and infectious. Furthermore, it showed that TMV could only be cultured in living, growing plants. This report, suggesting that “microbes” need not be cellular, would forever change the definition of pathogens. In 1946, Wendall Stanley was awarded the Nobel Prize for his isolation of TMV crystals, which he wrongly suggested were composed entirely of proteins. Research by FC Bawden and N. Pirie in England during the same period correctly demonstrated that TMV was actually a ribonucleoprotein, composed of RNA and an envelope protein. In the mid-1950s, German and American scientists proved that RNA alone was infectious. This discovery marked the beginning of the modern era of molecular virology. TMV is known for several "firsts" in virology, including the first virus to be made of RNA and proteins, the first virus characterized by X-ray crystallography to show a helical structure. , and the first virus used for electron microscopy, solution electrophoresis and analytical ultracentrifugation. TMV was also the first genome of an RNA virus to be completely sequenced, the source of the first viral gene used to demonstrate the concept of protein-mediated protection.