A field experiment was conducted at Sakha Agricultural Research Station Farm, during the two successive growing seasons (2008 and 2009) to study the effect of watering level and planting method on yield and crop water productivity of two rice varieties, Giza 177 and Egyptian Hybrid 1.
Statistical design was split split plot; main plots were allocated to planting method (broadcasting and transplanting), while sub-plots were assigned to be rice varieties (Giza 177 and Egyptian Hybrid 1). Sub-sub plots were the watering levels; watering as traditional in the area (Trad.), 75% of traditional watering ( 0.75 Trad.) and watering according to Ibrahim equation,1981 (Ib. eq.).
The obtained results can be summarized as follows:
Watering level affected plant height, where watering according Ibrahim equation reduced plant height of rice plant by 5.02 % in the first season and by 6.97 % in the second one.
Decreasing watering level from traditional method to 0.75 of traditional method reduced grain yield by 49 Kg fed-1 in the first season and 33 Kg fed-1 in the second season ( in both seasons the difference is not significant ).
Decreasing watering level from traditional method to watering according Ibrahim equation reduced grain yield by 673.5 Kg fed-1 (14.55 % reduction) in the first season and by 630 fed-1 (13.91% reduction) in the second season ( in both seasons the difference is highly significant ).
Grain /Straw Ratio of variety treatment means were 0.700 for Giza 177 and 0.980 for Egyptian hybrid 1 in the first season and the corresponding values of the second season were 0.770 and 0.952 . Grain /Straw Ratio of Egyptian hybrid 1 was decreased with decreasing watering level under the study .
The means of 1000 grain weight of Giza 177 were 25.68 and 25.82 gm in the first and second season, respectively. The means of 1000 grain weight of Egyptian hybrid 1 were 24.45 and 24.88 gm in the first and second season, respectively.
watering according to 0.75 of traditional + Giza 177 assigned 3.310 gm rice grain panicle-1 compared with 3.055 and 2.685 gm panicle-1 for watering as traditional + Giza177 and watering according Ibrahim equation + Giza177 treatments, respectively. The same means for the same treatments in the second season were 3.275 gm panicle-1 compared with 2.865 and 2.890 gm panicle-1, respectively.
In the first season watering according to traditional + Egyptian hybrid 1 assigned 4.385 gm rice grain panicle-1 compared with 4.025 and 3.600 gm panicle-1 for watering as 0.75 of traditional + Egyptian hybrid 1 and watering according Ibrahim equation + Egyptian hybrid 1 treatments, respectively. The same means for the same treatments in the second season were 4.540 gm panicle-1 compared with 4.165 and 3.595 gm panicle-1, respectively.
The lower Crop water productivity values ( 0.747 and 0.718 kg m-3 ) were assigned with Giza 177 and the higher values (0.895 and 0.852 kg m-3) were assigned with the latest one ( Egyptian hybrid 1).
Crop water productivity of traditional watering, 0.75 of traditional watering and watering according to Ibrahim equation treatment means were 0.705, 0.850 and 0.908 kg m-3 in the first season . Similar values for the same treatments in the same order in the second season were 0.703, 0.833 and 0820 kg m-3 .