The world is facing a critical challenge: feeding a growing population while protecting the environment. By 2050, global agriculture must increase productivity by 70% to meet food demands.
However, climate change, soil degradation, and the overuse of chemical fertilizers and pesticides are making this goal harder to achieve.
One promising solution lies in the use of Trichoderma, a group of beneficial fungi that can enhance the growth and resilience of oilseed Brassica crops like rapeseed, mustard, and canola.
The Importance of Oilseed Brassica Crops
Oil seed Brassicas, or OSBs, are a group of plants within the Brassicaceae family that play a vital role in global agriculture and nutrition. Key species include Brassica napus (rapeseed), B. juncea (mustard), and B. rapa (turnip).
These crops are not only a rich source of edible oils but also packed with essential nutrients like vitamins C and E, minerals such as iron and calcium, and bioactive compounds like glucosinolates (GSLs), which have anticancer and antimicrobial properties.
In 2023, global rapeseed production exceeded 88 million tons, with the European Union and Canada leading the way. Mustard seeds, another important OSB, yielded 687,000 tons in 2021, primarily in Asia.
Vegetables like cabbage and broccoli also contribute significantly, with over 98 million tons produced in the same year. Despite their importance, OSBs face numerous challenges.
Climate change is causing more frequent droughts, salinity, and extreme temperatures, which reduce yields by 10–80% in some regions.
Additionally, soil degradation has rendered 24% of global land unusable for farming, while pathogens like Sclerotinia sclerotiorum (stem rot) and Alternaria brassicae (leaf spot) continue to devastate crops.
How Trichoderma Fungi Are Changing the Game
Trichoderma fungi, first described in 1794, are naturally found in soil and plant roots. Over 500 species have been identified, and their benefits for agriculture are well-documented.
These fungi act as biofertilizers, biocontrol agents, and stress alleviators, making them a versatile tool for sustainable farming.
As biofertilizers, Trichoderma fungi help plants absorb essential nutrients like phosphorus and nitrogen. They also produce growth-promoting hormones such as auxins, which stimulate root and shoot development.
As biocontrol agents, they protect crops from harmful pathogens by parasitizing them or competing for space and nutrients. For example, Trichoderma can suppress soil-borne diseases like Fusarium wilt and Rhizoctonia root rot.
Additionally, these fungi enhance plant tolerance to abiotic stresses such as drought, salinity, and heavy metal contamination.
Globally, Trichoderma-based products make up 50–60% of commercial biofungicides. India leads the way in research, with 21 studies on OSB-Trichoderma interactions, followed by China, Iran, and the USA.
This widespread interest highlights the potential of Trichoderma to address some of the most pressing challenges in agriculture.
Genetic Engineering: Boosting Brassicas with Fungal Genes
One of the most exciting applications of Trichoderma is in genetic engineering. Scientists have successfully transferred genes from Trichoderma into oilseed Brassicas, giving these crops new abilities to resist diseases and tolerate environmental stresses.
For instance, the chit42 gene from T. atroviride, which encodes an endochitinase enzyme, has been introduced into rapeseed (B. napus).
This gene helps the plant resist Sclerotinia sclerotiorum, a pathogen that causes stem rot and can reduce yields by 10–80%.
Transgenic rapeseed plants showed 40–50% less fungal growth, significantly improving crop health.
Similarly, mustard plants (B. juncea) engineered with Trichoderma genes resisted Alternaria brassicae, a fungus that causes leaf spot, reducing infected leaf area by 73%.
Another breakthrough involves the Thkel1 gene from T. harzianum. This gene enhances drought and salt tolerance in rapeseed by increasing the activity of β-glucosidase, an enzyme that helps plants cope with stress.
Remarkably, transgenic rapeseed with Thkel1 also achieved root colonization by arbuscular mycorrhizal fungi—a rare feat for Brassicas.
This symbiosis improves nutrient uptake and reduces the need for chemical fertilizers, offering both economic and environmental benefits.
Direct Application: Real-World Benefits of Trichoderma
Beyond genetic engineering, Trichoderma fungi are being used directly in the field to boost crop growth, improve resilience, and combat diseases.
Growth and Yield Improvements
In laboratory trials, T. harzianum increased mustard seed germination by an impressive 97%. In the field, rapeseed treated with T. viride showed a 17% increase in yield under drought conditions, with larger siliques and heavier seeds.
Additionally, T. harzianum-treated rapeseed grains had higher levels of nitrogen and sulfur, enhancing their nutritional value.
Resilience to Environmental Stresses
Trichoderma also helps crops withstand harsh conditions. For example, mustard plants exposed to high salinity (200 mM NaCl) maintained their chlorophyll and oil content when colonized by T. harzianum.
In cadmium-contaminated soils, T. koningii increased rapeseed growth by 23% and boosted the plant’s ability to absorb and store heavy metals, aiding in soil detoxification.
Disease Suppression
Trichoderma fungi are highly effective at controlling both soil-borne and foliar diseases. In mustard, they reduced infections caused by Macrophomina phaseolina (charcoal rot) and Rhizoctonia solani by competing for nutrients and parasitizing the pathogens.
In rapeseed, root colonization by T. harzianum triggered systemic resistance, lowering infections from Sclerotinia sclerotiorum by activating defense pathways involving jasmonic acid (JA) and salicylic acid (SA).
Challenges and Future Directions
While Trichoderma offers immense potential, there are challenges to overcome. Not all strains are beneficial; some produce phytotoxic metabolites that can harm crops.
For example, T. polysporum’s metabolite 1,8-propanediol o-xylene inhibited rapeseed germination by 87%. Additionally, rare cases of Trichoderma causing infections in humans or harming non-target insects highlight the need for rigorous safety assessments.
Future research should focus on understanding the mechanisms behind Trichoderma’s benefits, such as how it alters GSL hydrolysis in Brassica roots or enhances heavy metal tolerance.
There is also a need to explore its potential against insect pests, which currently have limited data. Finally, developing cost-effective and shelf-stable formulations will be crucial for widespread farmer adoption.
Conclusion: A Sustainable Path Forward
The partnership between Trichoderma fungi and oilseed Brassicas represents a promising path toward sustainable agriculture.
By enhancing crop growth, improving resilience to environmental stresses, and reducing the need for chemical inputs, Trichoderma aligns with global goals like the EU’s “Farm to Fork” strategy, which aims to cut chemical pesticide use by 50% by 2030.
As research continues to unlock the full potential of Trichoderma, it could play a key role in ensuring food security for a growing population while protecting the planet.
By integrating genetic engineering, biofertilizers, and biocontrol, farmers can achieve higher yields, healthier soils, and a more sustainable future.
Reference: Sánchez-Gómez, T., Martín-García, J., Santamaría, Ó., & Poveda, J. (2025). Improvement of oilseed Brassica crops by Trichoderma use: gene transfer and direct interaction. Oil Crop Science.
