2016 年 26 巻 3 号 p. 179-181
This study was conducted during two successive seasons 2009 and 2010 on ten years old “Manzanillo” olive trees, planted at 5 × 5 m grown in sandy soil in a private orchard at Cairo-Alexandria desert road (about 50 km from Cairo), Egypt. The investigation aimed to study the effect of dates of ammonium sulphate 20.6%N applications as nitrogen fertilization source and minimize the rate of added annually amounts by 20% on vegetative growth and photosynthetic pigments of “Manzanillo” olive trees. The obtained results indicated that the application with ammonium sulphate at 1 kg/tree in each of February, May, June and August increased significantly vegetative growth; leaf area, leaf dry weight and specific leaf weight and photosynthetic pigments.