RESUMO
An experiment was conduced at Al-Mshkhab Rice Research Station for growing season of 2001. The aim as to study the response of three new introduced rice cultivars to Iraq. i.e. Al Somood; yasmin and Al-bernamag. 4 under the effect of watering periods [Continuous flooding "control" and watering applied to two intervals, after 5 and 10 days] and fertilization level [soil application by K and foliar application by Zn. Four treatment were used. [control; K [30 kg/Donum; 2K [60 kg/Donum and K+Zn [30 kg/Donum + 1.0 g/L., respectively]. Split- Split plot Design was used with three replicates. Duncans Multiple Rang Test was used to compare means at probability level of 5 percent. Four leaf chemical contents besices productivity were studied. Results indicated that: - A reduction in chlorophyll a, b; carbohydrates contents and productivity with plants grown by watering after 10 days, whereas, praline, content increased with the above watering treatments. - Al-sommod cultivar produced the highest contents from chlorophyll a and praline, whereas, Al- bernamay 4. Produced the highest contents for chlorophyll b and carbohydrates. These two cultivars were for differ in productivity. - Chlorophyll a and carbohydrates contents increased with treatments of 2K, and K+Zn. Chlorophyll b and productivity increased with K+Zn. Proline content decreased with the above fertilization treatments. - Fertilization treatments [K+Zn] with Al- somood and Al- bernamag 4 cultivars with flooding watering interactions produced the best values of chlorophyll a, b; carbohydrates and productivity. Mean while, the interaction between plants of yasmin culivars with out fertilization treatment and watering applied after 10 days produced the highest content of proline