1 : the arrangement of foliage in most plants (as in the common ivy) in such a pattern as to expose the maximum number of leaves to the direct rays of the sun with little loss of intervening space.
What causes leaf mosaic?
mosaic, plant disease caused by various strains of several hundred viruses. A number of economically important crops are susceptible to mosaic infections, including tobacco, cassava, beet, cucumber, and alfalfa.
What is mosaic formation in plants?
Mosaic formation is the presence of some light and dark green patches in the leaves of plants which is mainly caused by the viral diseases. Leaf rolling is curving the leaves of plants outwards. Due to some diseases the plant which is mostly green in color gets converted into the yellow color plant.
Which disease is caused for mosaic disease?
This disease is caused by a complex consisting of the monopartite begomovirus Bhendi yellow vein mosaic virus (BYVMV, family: Geminiviridae) and a small satellite DNA beta component. BYVMV can systemically infect bhendi upon agroinoculation but produces only mild leaf curling in this host.
What is meant by mosaic disease?
/ (məˈzeɪɪk) / noun. a serious viral disease of plants, esp tobacco, maize, and sugar cane, in which the leaves become mottled by discoloration.
How do you know if a plant has a mosaic virus?
How to Identify Mosaic Viruses and Damage
- The leaves are mottled with yellow, white, and light and dark green spots, which appear to be elevated. …
- Plants are often stunted, or they grow poorly.
- Plants may have other deformities and their leaves may be crinkled or wavy.
Is mosaic virus harmful to humans?
“These viruses are specific to plants and do not harm humans. The presence of mosaic won’t cause fruits to rot prematurely but severely distorted fruit will have a different texture, so use your own judgement.”
What are yellow leaves?
Known as chlorosis, yellowing happens when something interferes with your plant’s chlorophyll — that’s the plant pigment behind their beautiful green color. The good news is that yellow leaves let you know plants need help.
What is leaf mottling?
Mottle is a pattern of irregular marks, spots, streaks, blotches or patches of different shades or colours. It is commonly used to describe the surface of plants or the skin of animals. In plants, mottling usually consists of yellowish spots on plants, and is usually a sign of disease or malnutrition.
What is a rolled leaf?
Definition of roll-leaf
: gold or foil laid on thin glazed paper and put up in rolls for feeding out mechanically in a stamping press.
Is mosaic virus contagious?
Tomato mosaic virus is a serious and extremely contagious disease. It is also hard to identify, with symptoms varying wildly depending upon the variety and age of the infected plant, the strain of the virus, and environmental conditions.
What plants can get mosaic virus?
Mosaic viruses affect a wide range of edible crops – alfalfa, apples, beans, celery, corn, cucumbers, figs, peppers, spinach, tobacco and tomatoes are some of the more common ones. They can also infect ornamental plants like abultilon, delphinium, gladiola, marigold, petunia and one of the most notable, roses.
How fast does mosaic virus spread?
Comments on the Disease
Cucumber mosaic virus is spread from plant-to-plant by many species of aphids. Aphids only retain the ability to transmit these viruses for very short periods of time (minutes to a few hours). Thus, spread is often very rapid and local.
Is Mosaic a virus?
A mosaic virus is any virus that causes infected plant foliage to have a mottled appearance. Such viruses come from a variety of unrelated lineages and consequently there is no taxon that unites all mosaic viruses.
What determine the severity of symptoms of Mosaic?
Disease severity generally depends upon the host genotype, and is usually more severe on susceptible than on resistant genotypes (Hahn et al., 1980; Jennings, 1994; Thresh et al., 1994).
How can we control yellow mosaic virus?
— Infected plants should be removed. — Remove and destroy disease-affected leaves/plants from crop fields to avoid secondary spread. — Destroy host weeds. Intercrop with non host crops like sorghum, pearl millet and maize.