Question: what mold is there on my seedlings?
some fat cactaceous plants create a white mold for almost the whole plant and then die as I can to eliminate that muffin that I suppose is a mushroom thanks paolo
Cottony cochineal: Answer: cactaceae parasites
generally the succulent plants are not affected by mold on the outside, as they live in a dry environment, especially if grown in the apartment; It is more likely that the parasite that you notice in the form of white mold is the cochineal; this insect develops a patina similar to mold or pure white cotton, and is in fact commonly called cottony cochineal; it nestles on the stem of cacti, but also under the foliage of apartment and garden plants, or among the roots of plants grown at home. It is a very harmful pest, as it has a mouthpart that is capable of piercing the epidermis of succulent plants and sucking its sap; in addition to direct damage, due to the "theft" of lymph, often through the holes caused by insects, a series of bacteria enter the plant, which also ruin the plant from the inside, causing wounds that are clearly visible, with light-colored patches , or yellow. It is not easy to eradicate the cochineal, as every single insect can produce many eggs, which develop rapidly. So it is essential to act promptly, as soon as you notice even a single cochineal. If the insects are few, just remove them with a cotton swab dipped in denatured alcohol. If, on the other hand, it is a large infestation, such as the one you described, it is necessary to clean the plant with a microfibre cloth, or with cotton (it then depends on what plant we are talking about, or if it is a small semi-spherical or a cactus of meters in height); therefore it is necessary to carry out a treatment using white oil mixed with an insecticide based on pyrethrum. When the bugs die in a few days, you will have to try to remove them from the plant. If the plants are infested with great rapidity, it is probable that the scale insects nest in the vessels, from where they come out only when the population is already numerous; therefore in addition to the treatment on the outside, it will be necessary to remove the plants from the pot, remove all the soil and sprinkle the roots with a broad-spectrum insecticide, leave the plant to dry for a couple of days and repot it with new soil and in a new container. The empty jars will have to be washed well with hot water and bleach (or, in the case of a few jars of little value, it is also possible to eliminate and replace them). In general cochineals develop better in a warm, dry climate with poor ventilation; if your succulent plants live in a similar climate, consider that it will be advisable in the next few months to practice a couple of treatments with a systemic insecticide, or rather that it must be supplied in the water of the watering, from where it reaches the whole plant through the roots.