Vanilla Planifolia - Plant Disease and Insects

Vanilla Planifolia - Plant Disease and Insects 

The main factor of damage and a lower vanilla production are diseases. Vanilla grows under a temperature and humidity that is in favour of developing pathogens, which are mainly fungi.
So, I will write something about the general production of Vanilla and its diseases (not focused on Madagascar). It is always better to prevent diseases instead of controlling the damage it already did to the crop. Of course, when necessary, you can use a chemical control to avoid environmental contamination.
 

The main vanilla insect pest is the ‘Chinche Roja’ ((Tenthecoris confusus Hsiao & Sailer). It is a small insect that has multiple life stages, including 4 instars. At the nymphal stage, it causes the most damage to the vanilla plant. It is the single most damaging vanilla pest, causing tissue damage in the leaves, stems, and the fruits. The wound of the chinche help to the colonization of fungus and bacteria that cause rot, wilting and defoliation.

The chinche is controlled in a way that takes a lot of time. Hand by hand in the early morning hours when the chinche is present at low population density they start killing them. An organic control is prepared and sit for 48 hours. This is the way to prepare it: you dissolve get 3 onions, 3 heads of garlic juiced in a blender, a bar of pH neutral soap, in 40 Liters of water.

Root and Stem Rot (F. oxysporum f. sp. Vanilla) is the most common and most harmful fungal pathogen of vanilla, causing the roto and stem rotting and consequently the death of the plants.
The fungus causes varying degrees of damage and production losses in vanilla plantations throughout the world. (Hernández‐Hernández, J. (2011))

Controlling this fungus is very difficult when the plant is already infected. That is why prevention is recommended. You can do this by cultural methods such as; use of land with good drainage, use of healthy and vigorous cuttings, maintain a 10-cm cover of mulch over the roots, keep plants well-nourished, avoid overcrowding plants by maintaining an appropriate distance between the plants, avoid excess shade and excess sunlight, prune plants to remove infected parts, avoid over pollination, and sterilize any new planting areas.

There are ways to get rid of the Fusarium by using chemicals. Yet, these treatments are expensive not that practical, and they contaminate the ground.

Of course, this is not the only disease that exists in the vanilla crop. Here are some other examples of diseases that can be present in the vanilla crop:
Black Rot (Phytophtora SP.) =
This fungus is very aggressive, it can attack any part of the plant and kill it in only a few days. The disease is distinguished by watery injuries of greenish to blackish color and causes general rotting of the infected tissue.

It can be controlled by using the appropriate distance in between plants (1.5 to 2.0 meters between plants and 2.0 to 2.5 meters between rows). The tutors should be pruned to allow from 30 to 50% or more of sunlight. If part of the plant is affected by the disease you should remove it and burn it.

Anthracnose (Colletotrichum SP.) =
The fungal pathogen Colletotrichum sp. attacks leaves, fruits, stems, and flowers. Characteristic of the disease is the small sunken dark coffee spots, irregular in colour. It damages the leaves and the stem during the time called “nortes”, the season characterized by cold air and moderate rain

You can prevent the disease by maintaining a healthy root system and a good balance of plant nutrition. Another way is to apply any fungicide that contains copper oxychloride or mancozeb.

Rust (Uromyces SP.) =
Rust is characterized by the presence of yellow-orange spots on the leaves. As the disease advances, the pustules coalesce, eventually resulting in completely dried leaves

When a plant is affected you can control it by removing the leaves and burn them as soon as the symptoms show up. Also, it is important to increase the amount of light within the plantation.
(Hernández‐Hernández, J. (2011))

The main vanilla insect pest - Chinche roja 

References

Hernández‐Hernández, J. (2011). Vanilla diseases. Handbook of vanilla science and technology, 26-39.

Bhai, R. S., & Dhanesh, J. (2008). Occurrence of fungal diseases in vanilla (Vanilla planifolia Andrews) in Kerala. Journal of Spices and Aromatic crops, 17(2), 140-148.