Highly active biostimulant Paecilomyces variotii extracts reduced controlled-release urea application while...

Area of Science:

• Agricultural Science
• Agronomy
• Plant Science

Background:

• High cost of controlled-release urea (CRU) necessitates exploring reduced application rates.
• Biostimulants offer a potential strategy to enhance nitrogen fertilizer efficiency in rice cultivation.
• Investigating synergistic effects of CRU and biostimulants on rice yield and nitrogen management.

Purpose of the Study:

• To determine if biostimulants can reduce the required amount of CRU without compromising rice yield.
• To evaluate the combined impact of CRU and Paecilomyces variotii extract (ZNC) on rice yield, nitrogen use efficiency (NUE), and profitability.
• To assess the potential for sustainable nitrogen management in rice production.

Main Methods:

• A two-year field experiment was conducted using controlled-release urea (CRU) at 60%, 80%, and 100% of the recommended nitrogen (N) rate.
• A novel biostimulant, Paecilomyces variotii extract (ZNC), was applied at 87.5 mL/ha.
• Comparative analysis of rice yield, NUE, and net profitability across different treatment groups.

Main Results:

• CRU significantly increased yield and NUE compared to conventional urea.
• Even with a 40% reduction in CRU, rice yield and net profit remained significantly higher than with full conventional urea.
• The combination of CRU and ZNC (80% CRU + ZNC) achieved comparable yields to 100% CRU, demonstrating ZNC's efficacy in reducing N input.
• ZNC application enhanced panicle number, N accumulation, rice yield (by 9.2% and 8.7% over two years), NUE, N partial factor productivity, and net profit.

Conclusions:

• The combination of CRU and ZNC presents a viable strategy for reducing nitrogen fertilizer input in rice cultivation.
• This approach effectively maintains or increases rice yield, contributing to enhanced agricultural sustainability.
• The findings support the use of biostimulants to optimize nitrogen fertilizer management and improve farm profitability.