Abstract :
In order to study the effects of the planting date
on the plant height, yield components and seed yield of the
spring breeding lines and cultivars of rapeseed, an
experiment was conducted in the form of split plots based on
randomized complete block design with three replications at
the Baykola Agriculture Research Station during the 2010
and 2011 cropping seasons. Four planting dates including
Oct 19 (D1), Oct 30 (D2), Nov 9 (D3) and Nov 19 (D4) were
considered as the main factors and five rapeseed genotypes
viz. L10 (G1), Sarigol (G2), L7 (G30), L4 (G4) and Hyola401
(G5) were detected as sub factors. Results of the analysis of
the variance on the basis of the split plot design showed that
the planting dates mean squares were significant for all the
traits except seeds per pod. Genotypes had significant
differences for all the traits except pods per plant. The
interaction effects of the planting date and the genotypes (D
×G) mean squares were not significant for pods per plant,
1000-seed weight and seed yield, which indicating similar
trends of change for these traits in the genotypes in response
to different planting dates. In all of the cultivars, there was
considerable deterioration in most of the traits as a result of
delays in planting dates. All yield components had significant
positive correlation with seed yield, which indicated that
these traits and seed yield were affected in the same way by
different planting dates. In general, the high means value of
seed yield were belonged to G1 and G5 (3972.22 and 3638.89
Kg.ha-1, respectively) when planted at the earliest planting
date.
