[Absorption and utilization of different applied nitrogen forms by winter jujube]

Area of Science:

• Agricultural Science
• Plant Nutrition
• Horticulture

Background:

• Nitrogen is a crucial nutrient for plant growth and fruit development.
• Understanding the differential absorption and utilization of various nitrogen forms is vital for optimizing crop fertilization strategies.
• Winter jujube (Ziziphus jujuba var. spinosa) quality is influenced by nutrient availability.

Purpose of the Study:

• To investigate the absorption and utilization efficiency of urea nitrogen, glycine nitrogen (Gly N), and glutamine nitrogen (Glu N) in winter jujube.
• To compare the physiological responses and fruit quality impacts of different nitrogen sources.

Main Methods:

• A pot experiment was conducted using two-year-old winter jujube plants.
• Absorption rates, N allocation, transaminase activity, soluble protein, and nitrate reductase activity were measured.
• Fruit coloration and soluble solid content were analyzed after N application.

Main Results:

• All three nitrogen forms were absorbed, with urea N exhibiting the highest absorption rate.
• Glycine N and glutamine N showed lower relative absorption rates (28.88% and 11.73% in leaves, respectively).
• Amino acid nitrogen (Gly N and Glu N) significantly improved fruit coloration and soluble solid content compared to urea N.

Conclusions:

• Winter jujube can utilize urea N, Gly N, and Glu N, but with varying efficiencies.
• Amino acid nitrogen sources are more effective in enhancing winter jujube fruit quality attributes.
• Optimizing nitrogen source selection can improve both plant nutrition and fruit yield/quality.