الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 141 |  |  |
| | | from | 141 | | |
Abstract
The field experiments were carried out at Tawila area, Dakahlia Governorate, during the two summer seasons of 1997 and 1998, on two potato cultivars (Agria and Draga). The objectives of this study were to investigate the effect of three levels of farmyard manure (FYM), four NPK levels, two cultivars of potato tubers and the interaction between them on growth, yield, quality and chemical composition of potato tubers. Split split plot design was used in this work, since main plots were assigned to farmyard manure (0, 20 and 30 m3/fed.), while subplots were assigned to NPK fertilization ( Control, L1 = 7570140, L2 = 9085170, L3 = 105100200 kg NPK/fed.). The results of this study could be summarized as follows: 1. Vegetative growth characteristics: ?Increasing FYM levels up to 30 m3/fed resulted in the highest significant plant height, number of leaves / plant, foliage fresh weight and dry weight / plant, leaf area / plant and number of stolons / plant. ?Increasing NPK levels up to level two led to the highest significant plant height, number of leaves / plant, fresh and dry weight of foliage and leaf area / plant. Increasing NPK levels up to level three led to the highest significant number of stolons / plant. ?The plant height, number of leaves, foliage fresh and dry weight / plant, leaf area and number of stolons significantly increased with Draga cultivar cultivars compared with Agria cultivar in the two seasons of study. ?The plant height, number of leaves, foliage fresh and dry weight / plant and leaf area were increased as result of applying the FYM (30 m3/fed) combined with level two of NPK. On the other hand, the number of stolons increased with 30 m3/fed and level three of NPK during the two seasons of study. ?Fertilization of Draga cultivar with 30m3 FYM / fed significantly increased plant height, foliage fresh and dry weight / plant, leaf area and number of stolons / plant. However, the increment did not reach the level of significant with respect with number of leaves / plant at both seasons.