The mealybug is one of the most common pests on our indoor plants. Its scientific name is currently Pseudococcus viburni (Signoret, 1875) (former name: Pseudococcus affinis) is a species of hemiptera insects of the superfamily Coccoidea, a plant parasite.
Its body is covered with a secretion of white, waxy filaments, resulting in a chemical fight with little success. It is one of the most difficult crop enemies to fight! Its damage is variable, as much as the form it can take to conceal itself.
Each female lays 300-500 eggs in a bag. After laying the eggs, which can take 5-10 days, the female dies. The young mealybugs, which are very mobile, disperse and seek the ideal place to suck the sap of a plant. Before reaching the adult stage, the mealybug undergoes three pupations (the nymph represents the intermediate stage of development between the larva and *the imago during the metamorphosis moults of holometabolous insects).
* In biology, the term imago (in the masculine) or imaginal stage designates the final stage of an individual whose development takes place in several phases (usually egg, larva, imago). *Wikipedia
Its life cycle is highly temperature dependent. It lasts 90 days when the temperature is 18°C and 30 days when it is 30°C.
Mealybugs are to be taken seriously because an attack can definitively condemn your plant and those nearby! These pests feed on the sap of the plant which unfortunately ends up weakening.
In addition, they can cause the appearance of a black fungus called sooty mold. The leaves of your plant can become sticky because the mealybugs secrete honeydew (Honeydew is a thick, viscous liquid excreted by sucking biting insects which feed directly on the elaborate sap circulating in the phloem and reject this liquid through their anal tube, which , in the form of droplets, is deposited on the leaves), which leads to the formation of this fungus. Sooty mold, which looks like a layer of soot deposited on the leaves, is made up of the hyphae of fungi, which is blackish in color due to the presence of melanin in the cell walls. * Wikipedia
This makes the leaves sticky and unfortunately asphyxiates them.
But what solutions is the best to exterminate these pests?
In order to make the proper decisions, it is essential to start by using the right monitoring tools. It is advisable to use yellow sticky traps or delta traps to monitor adult males – the only stage of the life cycle during which they can fly. If the species is already known, it is preferable to use *attractive pheromones in the traps.
* The attractant pheromone is used as a lure for the detection, control, population monitoring and trapping of Cochineal. The diffuser releases the scent of a specific sex pheromone. This smell attracts the male flying mealybugs into the trap.
Here is the best recipe to eliminate these hateful insects!
This consists of diluting in 1 liter of water:
- 5 ml of liquid black soap,
- 5 ml of vegetable oil,
- 5 ml of alcohol at 70% or more.
How to use :
You spray this solution twice a day for the first application and then every 7 days for 4 weeks. The goal is to overcome not only mealybugs but also larvae and eggs laid!
And now, let's talk some science!
Did you know that some species of scale insects (especially Dactylopius Coccu) can be used to make food colorings (such as carmine red or E120)? This insect, which lives on cacti of the Opuntia variety, is mainly cultivated in Latin America; Peru being the world's largest producer. Also called carmine, the dye owes its name to the carminic acid found in the body and the eggs that the female produces. Carminic acid acts as a natural pesticide to protect the cochineal from its predators. At the time, carmine was also used as a clothing dye; hence the origin of the crimson hue. This color is also part of the history of Canada, because it was used in the manufacture of uniforms for members of the Royal Mounted Police. Carmine dye has been replaced by synthetic dyes like alizarin.
Various steps must be followed in the preparation of carmine. When harvest time comes, the female species spotted on the cacti are collected one by one. This is particularly meticulous work; the insects being both tiny and dried up. A rudimentary dye, usually called cochineal red, is obtained from pulverized insects. To obtain a purer dye (carmine red), the dried insects are immersed in boiling water, which is made basic by adding ammonia or sodium carbonate. The solution is then treated with aluminum salts, which produces the dye.
After a period of decline, carmine red is back in fashion. It is used as a replacement for synthetic food colorings which are suspected to have adverse health effects. It should be noted, however, that the term natural is not necessarily synonymous with safe. There have been very rare cases of severe allergic reactions (anaphylactic shock) associated with the use of carmine as a food coloring. Also, like synthetic dyes, carmine is sometimes associated with hyperactivity in children.
It should be noted that unlike the European Union, Canada leaves the manufacturer the option of specifying or not the name of the food coloring present! In any case, the term "color" is sufficient to meet government requirements. This measure can be a problem for people with allergies or those who are strictly vegetarians who avoid all animal products.
Until then, the next time you enjoy an “all natural” yogurt, spare a thought for these female Dactylopius Coccus, to whom you owe this privilege. Yum!! Last thing: Nearly 100,000 insects are required to prepare one pound of dye. *Source: https://www.sciencepresse.qc.ca/
Now that we know more about these insects, we are ready to hunt!