Two field experiments were conducted in a new desert reclaimed area, on canola
(Brassica napus L.), under a drip irrigation system, during 1997/1998 and 1998/1999
seasons', to study the effect of three irrigation levels, Viz. 280.02 (h), 560.04(12) and
1120.08(b) m³/fed., on yield and some yield attributes of AD 201 (V1) and B.P .S.
Tower (V2) varieties. A split plot design with three replicates was used, where
irrigation levels occupied the main plots, while the sub-plots were devoted to the two
varieties. Water use efficiency (W.U.E) was calculated fer all combination treatments.
Correlation, stepwise and path coefficients analysis were performed. The obtained results, in both seasons, revealed that significant increases due to
irrigation varying from 11 to 12 were seen with all traits, Then after the increases were
insignificant, except with respect seed yic:ld/fed., where the highest value were
detected on 12 (427.0 Kg/fed.) and la (510.0 Kg/fed.) in the first and second seasons,
respectively. The two varieties did not significantly vary to each other with respect to
seed yield/fed. and some other traits, while AD 201 surpassed B.P.S. Tower with all
traits. Interaction effect was insignificant with all respects except number of
silique/plant in the second season. The combinations (12 X V1) and (13 X V₁) gave the
pronounced seed yield / fed. in the first season, i.e. 534.0 Kg/fed. and 616.0 kg/fed. in
the second season. Water use efficiency was greater in the second season. The
combination of (12 X V₁) produced the highest W.U.E. values, Viz. 0.65 and 0.68
Kg/m³ in the first and the second seasons, respectively. All traits were positively and significantly correlated to each other. Stepwise
analysis indicated that number of silique/plant and 1000 seed weight were the most
traits in the predictions equation. Path coefficient analysis declared that the previous
two traits directly, indirectly and totally relative contribution were 53.39, 16.25 and
69.64 % for number of silique per plant and 2.75,0.51 and 3.26 % for 1000 seed
weight, respectively.