Fungal Elicitors from Trichoderma and Simplicillium Boost Salt Tolerance and Callus Growth in Medjool Date Palm

A new study published in Plant Cell, Tissue and Organ Culture (PCTOC) reveals that fungal elicitors derived from Trichoderma ghanense and Simplicillium obclavatum can dramatically improve salt-stress tolerance in Medjool date palm. The research demonstrates that these rhizosphere-isolated fungi, particularly the hydrolyzed extract of T. ghanense (Tg2), enhance embryogenic callus growth and stabilize ionic balance under high salinity.

Key Findings from the Study

1. Tg2 elicitor significantly improves callus growth under salt stress

In vitro calli were exposed to 0–300 mM NaCl with five elicitor combinations.
Two-way ANOVA showed strong effects of both salinity and elicitor type, with Tg2 producing the highest biomass at every salinity level, including 300 mM NaCl.

2. Machine learning confirms Tg2’s strong protective effect

The authors trained Random Forest, XGBoost, and Multilayer Perceptron (MLP) models to analyze callus fresh weight.
The MLP model achieved R² = 0.97, confirming strong predictive power and highlighting Tg2 and high salinity as major drivers.
Variable Sensitivity Ratio analysis ranked Tg2 as the second most influential factor after 300 mM NaCl.

3. Elicitors enhance ionic homeostasis in greenhouse trials

Plants treated with Tg2 displayed:

Lower Na⁺ accumulation
Higher K⁺ and Ca²⁺ retention
Stronger effects in young leaves

MANOVA, PCA, and heatmap analyses revealed distinct ionic signatures that separated elicitor-treated plants from controls, confirming improved ionic regulation under 0–18 dS/m salinity.

4. Elicitor treatment improves seedling performance

Under greenhouse conditions, Tg2-treated seedlings maintained:

Greener, wider leaves
Reduced necrosis
Better growth even at 18 dS/m salinity

These visual findings aligned with quantitative ionomic results.

Why This Matters

Salinity affects nearly 7% of global land, with projections suggesting increases toward the end of the century. Date palm, a vital desert crop, faces severe productivity losses under salt stress.
This study provides evidence-based support that fungal elicitors—especially hydrolyzed T. ghanense—can serve as effective biostimulants for saline agriculture and for improving tissue-culture-based propagation pipelines.

Reference

Shahmoradian, N., Zarghami, R., Alami Saeid, K. et al. Hydrolyzed Trichoderma ghanense and Simplicillium obclavatum elicitors improve ionic homeostasis and callus growth under salinity stress in date palm. Plant Cell Tiss Organ Cult 163, 58 (2025). https://doi.org/10.1007/s11240-025-03252-7