Four hybrid cultivars of sunflower were tested for
growth cheracters and productivity under three plant densi
ties at the Experiment and Research center of the Faculty of
Agriculture at !1oshtohor. Zagazig University in 1990 and
1991 seasonS. Cultivars were Alia, Pioneer 452. Pioneer 6431
and Pioneer 552. Plant stands/fad were 35000 (Dl), 23333
(D2) and 17500 (D3). Resullts showed significant to highly
significant differences among cultivare in plant height,
number of leaves/plant, head diameter and lodging percent
age. pioneer 6431 and Pioneer 552 were associated with high
percentages of lodged plants. Also, high percentage of empty
heads were associaled with Pioneer 6431 and Pioneer 552.
However, the three cultivare of Pioneer gave significantly
higher weight per head and achenes/héad than Alta. Pioneer
552 excelled, other varieties in 100—achene weight. As for
yield of heads/fad, achenes/fad, Alia exçelled other culti
vare in both traits. Oil percentage showed no significant
differences, however, oil yield for alta was significantly
the highest.
Results on stands show that sonic growth characters dif
fered significantly with stand. Plants grown under (D3) were
shorter, of thicker stem, less ability to lodge and gave
less empty heads. Weight of head, and achenes/ head were
superior under (D2). However, the highest head/yield,
achenes yield/fad and oil yield/fad were those obtained from
(Dl).
The interaction of dinsity x variety was significant for
the characters empty heads Percent. head weight achenes/
head 100—achene weight yield/fed and achene yield/fad.