IMPACTS OF ROW WIDTH AND PHOSPHORUS LEVELS ON WATER RELATIONS, GROWTH, YIELD AND NUTRITIONAL VALUE OF SUl'(FLOWER PLANT

Abstract

The current investigation was carried out at Giza Agricultural Research Station, Agricultural Research . Center, Giza, Egypt during the two successive growing seasons of 200 l and 2002, to study the impacts of row width and phosphorus levels on water relations, growth, yield and nutritional value of sunflower plant. Moreover, potential evapotranspiration estimated from some ET formulae (i.e.. Modified Penman, Penman Monteith and Doorenbos - Pruitt formulae), were compared with the actual ET to evaluate the efficiency of these formulae in prediction of water consumptive use and scheduling irrigation of sunflower.

The cultivar used in this study was Ero-Floor C.V. Sowing dates were 2"d of June and 28th of May in the first and second seasons, respectively. The harvesting dates were 5th and 2nd of September in the two seasons.

5.1. The Experimental Design

The experiments were laid out in split plot design with four replicates. The plot was 5.0m in length and 4.2m in width (plot area was 21 m2 ) and contained 6 ridges with the 70 em row width treatment and 3 ridges with the 140 em row width treatment. The main plots were devoted to row width treatments and the subplots were assigned to phosphorus treatments.