Microbial Allies from the Cold: Antarctic Fungal Endophytes Improve Maize Performance in Water-Limited Fields

Area of Science:

• Agricultural Science
• Microbiology
• Plant Physiology

Background:

• Climate change exacerbates drought stress, posing a significant threat to global food security, particularly for sensitive crops like maize (Zea mays).
• Fungal endophytes, microbes residing within plant tissues, show potential for enhancing plant stress tolerance.
• Antarctic fungal endophytes, adapted to extreme environments, represent an underexplored resource for agricultural applications.

Purpose of the Study:

• To evaluate the efficacy of Antarctic fungal endophytes (Penicillium chrysogenum and P. brevicompactum) in improving maize drought tolerance under field conditions.
• To assess the physiological and biochemical responses of maize plants inoculated with these endophytes under varying irrigation regimes.
• To determine the impact of endophyte inoculation on maize yield components under drought stress.

Main Methods:

• Field experiments with controlled irrigation regimes simulating drought stress (59% field capacity).
• Unmanned Aerial Vehicle (UAV)-based multispectral imagery to monitor vegetation indices (NDVI, NDRE, SIPI, GNDVI).
• Physiological and biochemical analyses including chlorophyll, carotenoid, proline content, lipid peroxidation, antioxidant enzyme activity, and secondary metabolite profiling.

Main Results:

• Inoculated maize plants exhibited significantly improved vegetation indices (up to two-fold higher) under drought stress, indicating enhanced resilience.
• Physiological improvements included higher photochemical efficiency, increased chlorophyll and carotenoid content, and reduced lipid peroxidation in inoculated plants.
• Yield components, such as cob weight and length, were significantly enhanced in inoculated plants, especially under drought conditions.

Conclusions:

• Antarctic fungal endophytes (Penicillium chrysogenum and P. brevicompactum) effectively enhance maize drought tolerance and improve crop yield.
• The integration of microbial biotechnology with UAV-based remote sensing provides a powerful approach for sustainable crop management in water-scarce environments.
• These findings highlight the potential of extremophilic endophytes as a valuable tool for developing climate-resilient crops and ensuring food security.