Up to 40% Yield Loss Caused by Ostrinia nubilalis

Listed in the National Inventory of Natural Heritage under reference 248127, Ostrinia nubilalis was first recorded in 1796 by Jacob Hübner as “Pyralis nubilalis” and illustrated in Book 6 of his collection of European moths focused on borers. Once known as the “Mugwort Borer,” it is now more commonly referred to as the “Corn Borer” or “Stem Borer.” At the larval stage, this pest can cause yield losses of up to 40% in corn crops during heavy infestations. Ostrinia nubilalis larvae damage grains and ears, pierce stalks, and weaken plant growth. Beyond direct losses, infestations increase mycotoxins, rendering the harvest unfit for consumption and leading to longer harvest times due to corn stalk lodging. The larvae also affect other crops like hemp, millet, sorghum, hops, sunflower, peppers, and mugwort.

Trichogramma Brassicae: A Proven Biological Solution

Over 60 years ago, in the 1970s and 80s, INRA (National Institute of Agricultural Research) identified Trichogramma brassicae, a parasitoid wasp that targets eggs, as an extremely effective tool in biological control against Ostrinia nubilalis larvae. This breakthrough was the culmination of biological control efforts that began between the World Wars (cf. International Conference on Corn Borer, April 25-26, 1929, at the Pasteur Institute). The success of this initiative led to the creation of a department and an annual journal, Trichogramma News, within the International Organization for Biological Control (IOBC) in 1982, dedicated to trichograms.

No Risk of Resistance in Pests

While insecticides and genetically modified Bt corn (Bacillus thuringiensis) lead to progressive resistance in Ostrinia nubilalis, trichogram use avoids any risk of resistance. The method is purely mechanical: the micro-wasps, Trichogramma brassicae, lay their eggs inside Ostrinia nubilalis eggs, preventing the larvae from developing. A single female can parasitize 80 to 110 host eggs during her lifetime, depending on conditions (Nicole Hawlitzky, 1992).

Safe for Farmers’ Health

Using trichogram releases eliminates the need for any health protection. No PPE (Personal Protective Equipment), REI (Re-Entry Interval), or PHI (Pre-Harvest Interval) are required. This solution is completely safe for farmers.

Respect for Beneficial Fauna

As a targeted biocontrol solution, trichogram releases do not harm beneficial insects or auxiliary fauna.

An Effective Alternative to Phytosanitary Inputs

Endorsed by the Ecophyto government program, which aims to reduce phytosanitary inputs by 50% by 2025, trichogram treatment is one of the 119 standardized actions available in the Ecophyto plan. It is eligible for CEPPs (Certificates for Phytopharmaceutical Product Savings) under numbers 2020-06 (formerly 2017-006) – “Control corn borer with trichogram releases” and 2021-087 – “Optimize corn borer control with equipment facilitating trichogram releases via service providers.” These belong to the “Use of Alternative Methods” lever, which represents 38% of the standardized actions in the Ecophyto plan. In 2002, 111,082 certificates were issued for action 2020-006 and 74 certificates for action 2021-087.