Generally, abnormal fruit set mostly in the form of setting parthenocarpic triple fruitlets is one of the most
economically important disorders, which appears in trees of numerous TC (tissue culture)-derived date cultivars
including cv. ‘Barhee'. To improve normal fruit set, fruit yield and fruit quality of such Barhee trees, effect of five
pollen sources (three endogenous sources; ‘Beraim’, ‘Shahani’ and ‘Zahidi’ and two internationally recognized
varieties; ‘Fard No. 4’ and ‘Jarvis No. 1’) at two pollination times (day of natural spathe cracking (DNC)1 and two
days later (DNC 2)2
) was investigated on young TC-derived ‘Barhee’ trees. The study was conducted as splitplot
in a randomized complete block design (RCBD), replicated three times, in hot, arid region of the southwest
of Iran during the year 2013. The results indicated that the ‘Zahidi’ pollen had caused the highest percentage of
normal fruit set (avg. 50.1%) and bunch yield (3.55 kg) significantly (P ? 0.05) superior than the other pollen
sources, followed by Jarvis No. 1 (36.6%). The pollination with ‘Beraim’ pollen produced the lowest percentage
of normal fruits (21.3%). The pollination at DNC was significantly (P ? 0.05) higher in normal fruit set and
bunch yield. The pollination with ‘Zahidi’ pollen at DNC brought the highest percentage of normal fruit set
(57.5%) and maximum bunch yield (4.59 kg) with acceptable fruit weight and size. Both mentioned factors and
the interactive effect significantly (P ? 0.05) influenced bunch ripeness. The pollen of ‘Jarvis No. 1’ at DNC
yielded the highest percentage of bunch ripeness (96.91%). This pollen which had the second best normal fruit
set and bunch yield was superior in showing off key metaxeic effects i.e. fruit volume, fruit weight, and pulp to
seed ratio (w/w). The pollination at DNC significantly (P ? 0.05) led to higher fruit length, diameter, volume
and weight. Ultimately, we concluded ‘Zahidi’ pollen as the best choice for increasing normal fruit set