Abstract:
In order to study of effects of
nitrogen fertilizer and cycocel on yield,
yield component and dry matter mobilization
of wheat (Triticum aestivum L.) a factorial
experiment was conducted based on
randomized complete block design with
three replications during 2014. Treatments
were included nitrogen rates in four levels
(without nitrogen application as control (N0)
and application 80 (N1), 160 (N2) and 240
(N3) kg ha-1 urea) and four cycocel levels
(without cycocel as control (C0), application
of 500 (C1), 1000 (C2), 1500 (C3) ppm).
Results showed that cycocel application
increased chlorophyll index, photochemical
efficiency of PSII (Fv/Fm) and dry matter
mobilization from shoots and stem.
Application of nitrogen and cycocel reduced
dry matter mobilization from shoots and
stem, contribution of remobilization from
shoots to grain and stem reserve
contribution in grain yield. Application of
nitrogen and cycocel as N3C3 had 58.5% and
46.26% more dry matter mobilization from
shoots and stem in comparison with N3C0.
The highest 1000-grain weight by 28.90 and
28.54 g, respectively, belonged to
application of cycocel as C2 and C3 and the
lowest 1000-grain weight by 26.93 g
belonged to the C0. The highest grain yield
(1.068 g per plant), number of grains per ear
(37.36) and 1000-grain weight (28.77 g)
were obtained in application of 240 kg ha-1
urea. It seems that the increase of Fv/Fm
ratio due to current photosynthesis in plants
that were grown under cycocel and nitrogen
treatments decreased mobilization of dry
matter and stem reserves to grain yield.
Generally, it was concluded that nitrogen
and cycocel can be as a proper tool for
increasing wheat yield.