Diseases of succulent plants   Gardening    History    Essentials of Gardening    Types of Gardening    Bonsai    Kids Gardening    Types of Plants    Herb Gardening    Hydroponics Gardening    Worldwide Gardening    Articles    Plant Diseases    Glossory
Free E-magazine
Subscribe to our Free E-Magazine on Gardening.
Learn More
Jimtrade.com : India Business to Business Directory
Business Directory of Indian Suppliers Manufacturers and Products from India.
India`s leading Yellow pages directory.
India`s leading Yellow pages directory.
Home > Types of Plants > Cacti and other succulents > Diseases of succulent plants
Diseases of succulent plants
A range of fungal and bacterial diseases affect succulent plants, some of which can collapse and die very rapidly, once the disease has taken a hold. The world abounds with fungal spores, which are opportunists, waiting for the correct conditions for germination. Generally, fungi do not affect cactus and succulent plant collections because of the relatively dry conditions used by most growers. Damp conditions are a universal requirement for activation of fungal spores, and many of the problems with fungal infection of succulent plants arise from failure of excessive watering or condensation to evaporate, because of unexpected or seasonal cold weather. Damage from insect pests, which penetrate the plant`s epidermis to feed on sap, may provide a route for entry of fungi into the nutrient-rich inner tissues. Hence, unexpected collapse of a plant is often the final symptom of a mealy bug infestation which has gone unnoticed. On the other hand, some fungi provide their own mechanisms for penetrating the epidermics.

Seedlings are especially susceptible to fungal attack of the lower stem which causes damping off. Once the seedling has wilted, it is usually too late to save it and preventative measure are a better option.

Some Fungal Diseases

Sooty MoldBlack or Sooty Mold: A ubiquitous fungus which is often seen on plants covered with honeydew from whitefly, mealy bugs etc or on plants with nectar-producing glands such as certain Ferocacti. Generally, sooty mould is more unsightly than harmful on otherwise healthy plants. However, it will attack seedlings following mechanical damage or excessively wet conditions and other weak or damaged plants.

Basal Stem RotBasal Stem Rot: Cold or damp conditions may lead to rotting of stems, often just around the soil level where damp soil may be in prolonged contact with the plants stem. The rotten tissues may go black or reddish brown depending on the plant and organism attacking it. If the stem is cut well above the rotten part, it may be possible to re-root or graft the healthy tissues and save the plant. Many people support the basal stems of difficult plants with a layer of grit above the potting medium, so that there will be little water retention against the stem in this critical region.

A range of brown or gray spots spots on leaves and corky brown marks on stems of are undoubtably due to fungal attack following damage or prolonged contact with drops of water. Others may reflect poor cultural conditions or the natural development of corky or woody stems as the plant matures. In many cases, fungal attack and poor culture are linked. Improving ventilation, temperature control, watering and application of fertiliser may help to prevent all sorts of problems.

Growers of Asclepiads will be familiar with black spots developing on the stem which spread and develop into sunken patches of dead tissues. This fungal infection can spread to the whole plant unless the affected part is removed promptly or treated with fungicide. Usually this happens after overal-liberal water, perhaps where water droplets fail to evaporate because of unexpectedly cold conditions.

Control of Fungal Diseases:

Once a plant has collapsed or the stems have started to become soft and rotten it is often too late to save it. However, an attempt may be made to save part of a valuable plant by cutting away the infected tissues with a clean knife, sterilised with methylated spirits. A wide margin of apparently sound tissue should be removed as the infection will almost certainly have spread further than is apparent. The remainder can be painted or dipped in a systemic fungicide such as Nimrod T or dusted with sulphur and rooted as a cutting or grafted onto a compatible stock.

Botrytis or damping off in seedlings can be avoided by lightly spraying the potting mix with a systemic fungicide such as Benlate or Nimrod T. Spraying with a copper sulfate solution is a traditional remedy, but copper fungicides may accumulate in the soil with potential copper toxicity to plants. Any seedlings that become infected should be removed promptly before more spores are produced, the remaining seedlings sprayed with fungicide and surface moisture allowed to evaporate.
More...
Pots and Containers Watering Soil, Light & Manure
Pests Plague Cacti a.. Diseases of succulen..
Indianetzone.com | Home | Sitemap | Contact Us