Excessive nitrogen fertilizer yields less attractive apples: research

JINAN, Jan. 4 (Xinhua) -- Waxiness significantly influences the luster of apples, and recent research by Chinese scientists has revealed the regulatory mechanism of nitrogen on the cuticular wax of apples. The findings suggest that an excessive application of nitrogen fertilizer inhibits wax accumulation, thereby affecting the "attractiveness" of apples.

Apples naturally develop a wax coating during their growth to help protect the fruit and retain moisture. A research team led by Li Yuanyuan, a professor at the Shandong Agricultural University, discovered a significant decrease in the wax content of both fruit and leaves in apple orchards where nitrogen fertilizer was excessively applied.

Subsequently, they selected and compared genetic materials from various apple samples collected from major apple-producing areas in Shandong, including the cities of Yantai, Zibo and Tai'an, and concluded that excessive nitrogen ultimately reduces wax accumulation on apples through a series of gene regulation pathways.

The findings also offer a theoretical basis for enhancing the defense of apples against biotic and abiotic stress, improving their color and luster, and extending shelf life, according to the researchers.