There Are A Few Rose Diseases That Are Bacteria And Virus Caused, Here Are Two Of Them
by Bob Bauer
Also knows as 'Witches' Broom'. Some rosarians jokingly refer to it as 'Rose AIDS'. This deadly affliction is 100 percent fatal. So if you see it, just dig up the plant and remove it from the garden as soon as possible, as the mites which spread the infection are present in the plant. There is NO cure for Rose Rosette. This affliction has three stages. The first stage is rapid, vigorous growth characterized by unusually dense formation of prickles on stems and canes. Canes appear overly large and purple or deep red in color. New leaves appear distorted and crinkled, often purple or deep red. The leaf stems may appear flattened and look almost like leaves. The second stage is the development of lateral growth having closely spaced internodes leaf buds. When leaf buds open, they become distorted or even fail to fully open, giving an appearance of rosettes. The third stage is characterized by spindly, chlorotic stem growth. Roses may show symptoms in as little as 3 weeks after infection, or they can have an incubation period of up to a year or more.
The symptoms of this affliction are described as 'virus like', because the exact actual organism which causes Rose Rosette has not actually been identified as of yet. The disease agent of Rose Rosette is transmitted from plant to plant by a tiny microscopic sized, wooly mite called Phyllocoptes fructiphilus. This is a type of mite called an eriophyid mite. This is NOT like a spider mite.
Hybrid Teas are less likely to be used as hosts by this mite. Heavily pruned roses seem to have the fewest problems. This disease was first detected in the 1930s in wild roses growing in the mountains of California and Wyoming. Then it spread to stands of Rosa multiflora, an almost perfect host, and moved across the country and into the Midwest. In the late 1970s and early 1980s, it swept like a wildfire up the Ohio River valley and into West Virginia. Today, it’s endemic wherever wild multiflora roses are found This viral infection is most common now in the Midwest where Rosa multiflora hedges are frequently planted and become infected.
Treatment: Fuggedabowditt! Just remove the infected rose and burn or destroy it. Same with the soil around it where the mites might overwinter. Prevention is possible by controlling mites, as this is how the virus is transmitted to the rose. But you should realize that miticides and other measures commonly used for treating spider mite infestations aren’t effective because this is a different type of mite. If it is a big problem in your garden you might want to keep hybrids of Rosa multiflora out of your garden. Many budded or grafted roses are on Rosa multiflora root stock, which needlessly worries some gardeners. Although Rosa multiflora is a host for the disease and for the eriophyid mite, a rose on multiflora roots is no more susceptible to rose rosette than it would be if it were on its own roots or on another type of root stock. It is apparently the top growth and specifically the petiole-cane junction that determines susceptibility. This affliction is NOT spread by pruners or by any other known agent besides the tiny mites. So it is not contagious in that way.
'BettyBoop'
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This is a cancerous looking growth produced by the infection of a bacterium - Agrobacterium tumefaciens. Crown galls usually are restricted to the roots, lower stems, and ower branches of infected roses. In some isolated cases crown gall may occur in the upper branches. Brown to brownish black in color, the actual galls are somewhat rounded, lumpy and rough in texture. The galls are rough, hard and woody when older; young galls may be smooth and somewhat spongy. The size can vary from 1/2 inch to several inches in diameter. The tissues on the inside of these galls is usually quite firm. Later in the development of the gall it can get decayed looking. Most crown galls are caused by the bacteria, but be aware that other things can look like them. Various insects can cause the formation of galls. Environmental conditions such as wind and falling branches that cause wounds can also lead to callus tissue that looks like galls. The crown gall bacterium originally enters plant through wounds made by wind whipping, transplanting, hoeing, grafting, and pruning. Other smaller wounds caused by insects, animals, or people can serve as avenues for infection to happen. Plants afflicted with crown gall can be stunted, produce smaller and chlorotic looking leaves and may become more sensitive to environmental stress. Severely infected plants will decline and eventually die. If the bud union is affected, you might as well just dig up the plant and throw it away. Remove it totally from the garden and burn or otherwise destroy it. Keep in mind that Crown Gall bacteria can survive in soil for more than 10 years, so just because you have removed previously infected roses and branches and it isn't currently infecting your roses, there is always the possibility that it will. Crown gall bacteria may be spread through contact with soil, water or contaminated tools. More information of this particular bacteria can be found here: Crown Gall - Agrobacterium tumefaciens
Treatment: Avoid wounding susceptible plants at or near the soil line. When the condition is observed, prune infected branches and roots well back into healthy tissue as soon as possible. To prevent possible spread of the disase, sterilize your pruning tools by dipping them between cuts with a 1:4 solution of household bleach and water. 'Galltrol' or 'Gallex' is a biological control material used for the prevention of crown gall. The product is painted on galls and cut surfaces in the spring and early summer.
'Matador'
'Norwich Castle'