Biennial bearing and protein content of apples as influenced by high concentrations of foliar nitrogen and sulfur
1998
Izadyar, A.B. | Malakouti, M.J. | Talaie, A.R. | Fallahi, E.
Effect of different foliar applications of urea and ammonium sulfate at high concentrations after 8, 9, and 10 weeks of full bloom were studied in "on" selected 'Golden Delicious' and 'Redspur Delicious' alternate bearing apple trees. Leaf samples were taken one week before and after sprays for protein analysis with Near Infrared Reflectance (NIR). Percentage of flowering and fruit length to diameter ratios (L/D) were measured in both cultivars. Number of fruits only in 'Redspur Delicious' were recorded during "on" and "off' years. Spray of nitrogen (N) and sulfur (S) increased leaf protein content up to a certain level in all treatments. Leaf protein content in leaves of all application dates were significantly higher than non-sprayed in both cultivars. Foliar applications at different periods reduced flower percentage. Foliar sprays increased number of fruits in 'Redspur Delicious' in the "on" year, but did not affect different treatments during the "off' year. The sprays in 8, 9, and 10 weeks of full bloom intensified alternate bearing in the following "off' year.
显示更多 [+] 显示较少 [-]