The tuta absoluta (also known as the tomato tuta, or as the “tomato moth”) is a Lepidoptera that belongs to the Gelechiidae family. This species is common in regions of South America, although we can rarely find it in cold latitudes, or in those that are above 1000 meters of altitude. The most common cases detected in Spain have been in more or less severe areas.
In the adult phase, it will evolve to a moth characterized by having grey wings with some dark spots. It lays yellow eggs and places them on the underside of the leaves. When the larvae emerge, they have a cream color and a tan head. It is essential to differentiate it from the potato moth; they are similar, although the characteristics are entirely different.
The tuta of the tomato, in its final larval stage, has a green color with pink spots, having a length ranging from 1 to 8mm.
From the moment it emerges from the egg, the larva feeds on the first thing in the environment. In this way, the tuta absoluta will make holes in the tomato plant, both in the area of the stems and in the leaves. And they are well visible nooks and crannies. Concerning the leaves, it will create white galleries (as it only feeds on the mesophilic); in this way, the leaf will present a translucent white color, which will precisely be one of the main ways we have to identify the problem.
It also affects fruits. In general, they will spoil because internally they will rot. If the problem is not controlled, this rot will soon extend to the rest of the harvest.
How to detect the Tuta absoluta or Tuta of the tomato?
As we have already mentioned, the larva will feed on the stems or leaves; this will depend on the environmental conditions. The pulp larva can be easily seen; it will be necessary to identify the natural white cocoon with a silky texture. However, if we know this cocoon, it may already be too late for the plant, and it is precisely in the larval stage that it will be the time of time when the most severe damage occurs.
A homemade trap can be used for the tuta of the tomato to locate it as soon as possible: sex pheromones characterize these plants. In other words, it will emit pheromones, and this will attract moths. As soon as they reach the trap, they will be trapped on a water surface. There are also other methods of control, although the water trap is usually the most effective.
Methods to kill the pest
The truth is that by establishing simple daily routines we can keep tuta absoluta under control: We will have to remove weeds regularly, rotate crops so as not to feed this species, etc…
If it is detected that part of the crop has been affected, the remains must be burned to prevent the problem from increasing. This process is quite hard since we will be practically finishing with all our effort. However, few ways are as effective in preventing the pest from leaping to other species.
Some insects are predatory species of the tomato tuta, such as Macrolophus caliginous or Nesidiocoris tenuis. That is why we can buy these insects to end the plague. It may be a good idea, but it is a method that requires a lot of control, and there is no guarantee of success.
It will also be necessary to verify that the insects that are going to be introduced are not going to end up devouring another species that we have planted in the orchard.
If you’re looking to fight the absolute tuta of tomato organically, neem oil is what you need. This oil is unbearable for the plague, so well applied, it can help us solve the problem from one moment to the next.
The experts recommend us to apply it in the structure of the using a sprayer.
These traps are quite similar to pheromone traps. However, the operation is slightly different: in this case, moths are not attracted by pheromones, but by a colored plate. As soon as they arrive, they will stick together.
We can buy them commercially, or make a homemade trap by applying a little Eva glue and rat glue.
Like pheromone traps, this method is usually quite effective. We only have to worry about placing the trap in the right place, the one where it will be easier for the plague of Tuta absoluta to get stuck.
This compound is a special powder that must be diluted in water before being applied. In case you want to use it to treat the tomato tuta, it should be applied to the leaves from top to bottom for about a couple of weeks. It is considered an effective insecticide for tomato tuta, but before its application should be evaluated all the risks of conventional pesticides on the rest of the harvest.
However, it is a biological and effective treatment. From the first application, the larvae will ingest the tissues of the bacteria. When this sporule, it will create crystals-endotoxins of proteins that will perform an insecticide action. The spores will be activated in the insect’s digestive system, destroying its ability to feed itself. In the end, it will starve to death, so the pest will not be able to survive in any way.
As you can see, there are many ways to fight the Tuta absolute pest, although it is advisable to start as soon as possible to prevent it from spreading.